Climate Science | Science Matters

Gravity-induced Atmospheric Thermostat

Michel Thizon published in 2024 a paper explaining why earth’s always variable climate is constrained within a narrow range. Influence of Adiabatic Gravitational Compression of Atmospheric Mass on the Temperature of the Troposphere. Excerpts in italics with my bolds and added images

ABSTRACT

The temperature that the Earth’s surface would have without the greenhouse effect, with an atmosphere completely transparent to infrared radiation, or even without an atmosphere at all, is generally estimated at -18°C. The greenhouse effect is estimated to induce a warming of 33°C to justify the surface temperature of +15°C.

To explain this discrepancy, we examine, with the ideal gas law, to which the Earth’s atmosphere obeys with its normal conditions of pressure and temperature, the role that the adiabatic compression of the atmospheric mass subjected to gravity can play. The dimensional analysis of the ideal gas law demonstrates that compression of the atmosphere produces energy, which can be calculated in Joules.

The temperature of the atmosphere near the Earth’s surface is influenced by
its invariable atmospheric mass, solar irradiation and the greenhouse effect.

This calls into question the commonly established Earth’s energy budgets which consider almost exclusively radiative effects, and which deduce a back radiation attributed to the greenhouse effect which is abnormally high.

Earth temperature without atmosphere or greenhouse effects

Goody et al., estimated the solar energy available to heat, both directly and indirectly, the earth and its atmosphere at an average of 224 W/m-2 [1]. Applying the Stefan-Boltzmann law they assumed that the Earth radiates as a perfect black body in the infrared band at a temperature of 255.5 K (or min 17.6°C) for the effective emission temperature [2]. These authors noted that this temperature is lower than the average temperature of the Earth’s surface and indicated that much of the radiation to space must come from the atmosphere rather than from the surface. Goody et al., arbitrarily assigned a value of 1 to the emissivity ε for the calculation, while Jacquemoud assigned a value of 0.98 [3].

According to Hansen, a solar irradiance of 1367 W/m-2 or generally accepted today 1361 W/m-2, but varying with solar fluctuations, leads to a surface temperature of 255 K (or min 18°C), which induces a greenhouse effect of +33°C [4] Cotton reported that the emission temperature is -19°C and the earth temperature is +14°C, which corresponds to a global greenhouse effect of +33°C [5]. The global greenhouse effect is also estimated at +33°C [6-8]
.
Logically, at -18°C the surface of the earth without an atmosphere or with an atmosphere totally transparent to longwave radiation and that plays no physical role, without any greenhouse effect, should be entirely frozen and covered with frost over its entire surface. This would result in a high Albedo which could be on the order of 0.5 to 0.9 instead of an albedo of 0.30 or 0.29 generally accepted in its current state. In this situation, instead of the solar energy absorbed by the surface reaching approximately 160 to 168 W/m-2 (Figure 1) this energy could be on the order of 70 W/m-2 [9-11]. The Stefan-Boltzmann formula yields a potential surface temperature of approximately -85°C [2]. Note that at these temperatures the water vapor pressure above ice is infinitesimal and could only generate an infinitesimal greenhouse effect. However, according to Nikolov et al., the effects linked to the atmosphere would bring approximately 90°C and not 33°C to the surface at a temperature of 15°C [12,13]. This would suggest that the global natural effect of atmosphere could be on the order of 90°C rather than the 33°C of the traditional purely radiative approach as reported by almost all the authors.

Global mean energy budget of the Earth

Many authors have endeavored to establish an overall assessment of the energy flows to which the earth is subjected to justify the surface temperature in an essentially radiative system. The Intergovernmental Panel on Climate Change (IPCC) itself places great emphasis on this in each of its reports. The Figure 1 summarizes the values and differences obtained while Table 1 summarizes the main authors who evaluated this earth assessment over a period of approximatively twenty years.

Figure 1. Range of nine energy balances (minimum/maximum according to the authors).

Table 1. Global energy balance of the Earth according to the authors.

The dispersion and imprecision of the results do not allow the effect on surface temperature to be deduced with sufficient accuracy. These budgets must be improved as noted by Lupo et al. [22]

Effect of atmospheric pressure

Few authors have mentioned the role that an atmospheric mass subject to gravity could play in temperature. We can nevertheless cite Leroux [23] Jelbring [24], and Chilingar [25] but these authors evoke a potential role of atmospheric pressure on a qualitative level without seeking to calculate and quantify the effects, probably given the difficulty of integrating the atmosphere as a whole. Nikolov et al. clarify the role of atmospheric pressure for several planets through a complex semiempirical iterative approach [11]

Dimensional analysis of the ideal gas law PV=nRT

The ideal gas law PV=nRT is one of the most fundamental laws of physics and applies entirely to the lower troposphere under its usual conditions of pressure and temperature. This universally accepted law, established in 1834 by Émile Clapeyron, has been perfectly stable for nearly 200 years, which is the case for very few physical laws.

P is the pressure (Pa);
V is the volume of the gas (m3);
n is the quantity of material (mol);
T is the absolute temperature (K);
R is the universal constant of ideal gases (8.314 J K−1 mol−1);

Dimensional analysis leads to:
R=PV/nT i.e., J K−1 mol−1=Pa.m3 K−1 mol−1, Hence J=Pa.m3=energy

The volume of air multiplied by the pressure to which it is subjected is considered energy (Joules). The atmosphere is heated by compression due to the gravitational field to which it is subjected. Isolated in space, the Earth can only exchange energy with space by radiation, but the atmospheric mass cannot radiate spontaneously since its homonuclear constituents O2, N2, and Ar are passive and cannot radiate.

The earth’s surface is warmer and the atmosphere cannot cool down on contact with it. The compression is thus adiabatic. The greenhouse gases contained in the atmosphere at low levels, mainly H2O and CO2, are capable of radiating at long wavelengths but do not interact radiatively with O2 and N2; additionally, they are under the influence of permanent terrestrial infrared radiation, which they are capable of absorbing, and which is generated continuously from the solar energy received by the Earth’s surface.

The process includes the upward expansion, toward vacuum of the agitated molecules whose kinetic energy decreases and therefore the pressure, which causes cooling with altitude. It is not due to a decrease in gravity which decreases by less than 3/1000 at a 10 km altitude but of a struggle between gravity and the suction of the vacuum, until the equilibrium which defines an adiabatic thermal gradient. Gravity nevertheless prevents air molecules from escaping into space. Only some H2 molecules can reach the release speed.

RESULTS Heating of the atmosphere in °K by adiabatic compression

Table 2. Data for an air layer 100 m thick. The left part is from U.S. Standard Atmosphere, according to The EngineeringToolBox [26]

As a tight approximation, for 100 m of atmospheric thickness
Altitude 0 m

PV=(10.13 × 104 Pa) (5.101 × 1016 m3)=5.167 × 1021 J
Volumetric heat capacity of air C=1256 J m−3 K−1 (at 0 m, 15°C)
For 5.101 × 1016 m3 of air; +1°K requires 1256 × 5.101 × 1016 J=6.41 × 1019 J
5.167 × 1021 J/6.41 × 1019 J=80.7
+80.7 K overheating due to pressure

Note: With an air layer of 200 m the precision is lower and leads to an overheating of 80.6 K

Gravity compression results, to the Earth’s surface, in 80.7°C of natural greenhouse energy equivalence, which means that to reach 15°C the initial temperature without atmosphere would be -65.7°C, very different from the -18°C admitted by radiative approaches for an inactive atmosphere.

Direct application of the ideal gas law T=PV/nR

Altitude 0 m T=(10.13 × 104 × 5.10 × 1016)/(2.165 × 1018 × 8.314)=287.1 K (+14.0°C)
Altitude 5,000 m T=254.9 K (-18.2°C)
Altitude 10,000 m T=222.4 K (-50.7°C)
Altitude 15,000 m T=215.3 K (-57.8°C)

The standard thermal gradient from 0 to 10 km is -6.49°C/km. The ideal gas law explains phenomena linked to temperatures up to 10,000 m in altitude. Beyond that, the results diverge, and other factors and phenomena are involved, like ozone and UV influence.

CONCLUSION

The temperature on the surface of the earth is mainly determined by the action of gravity on the atmospheric mass, which is an immutable fact on a scale of millennia. Climatic variations are the result of lesser phenomena. The solar influence is felt during the day by the direct radiation received, mainly when the sun is at its zenith, and the balance is modified by direct thermal exchanges between the sunny surface and the air in contact. The earth’s surface and the upper layers of the atmosphere radiate permanently towards space by emitting infrared radiation day and night, thus restoring the overall balance.

Surface infrared radiation is probably less intercepted in the lower troposphere by greenhouse molecules than is usually thought, thus explaining the surface temperature. However, there is an atmospheric dynamic, in particular through the water cycle, by evaporation-condensation, but whose overall energy balance is zero. Air mass movements and convection contribute to the overall dynamics, mainly due to the rotation of the Earth and the alternations between the presence and absence of solar radiation.

Astronomical fluctuations in sunshine, surface phenomena such as ocean currents, El Niño or La Niña phenomena, extreme weather phenomena or even volcanic eruptions, as well as other factors that are probably poorly characterized, lead to variations in surface temperature that nevertheless remain relatively damped due to the stabilizing effect of the invariable atmospheric mass subject to gravity.

Again, There is No Right to a Stable Climate

Posted on June 1 by Ron Clutz

Announced this week was this from Inside Climate News: Trump Executive Orders Violate Young People’s Rights to a Stable Climate, a Lawsuit Alleges. Excerpts in italics with my bolds.

Twenty-two young people from across the country sued the
Trump administration over the executive orders,
which prioritize the expansion of fossil fuels.

The complaint, filed Thursday in the U.S. District Court in Montana, challenges three executive orders: “Unleashing American Energy,” “Declaring a National Energy Emergency” and “Reinvigorating America’s Beautiful Clean Coal Industry.” The lawsuit argues that with the orders, the Trump administration knowingly is advancing an agenda that will increase greenhouse gas pollution that already is stressing the global climate to a dangerous extent.

The litigation argues the situation infringes on the young people’s constitutional rights to life and liberty, as well as falling afoul of other laws approved by Congress that protect public health and the environment. The plaintiffs want the court to declare the executive orders unconstitutional, block their implementation and reaffirm the legal limits on presidential power.

“From day one of the current administration, President Trump has issued directives to increase fossil fuel use and production and block an energy transition to wind, solar, battery storage, energy efficiency, and electric vehicles (“EVs”),” the lawsuit states. “President Trump’s EOs falsely claim an energy emergency, while the true emergency is that fossil fuel pollution is destroying the foundation of Plaintiffs’ lives.”

It’s the same argument from the same people (Our Children’s Trust) that was shot down in flames just a year ago. There were multiple attempts to undo the damaged legal maneuver to no avail. Below is why this latest litigation should be put out of its misery at once.

Appeals Court Rules Against Kids’ Climate Lawsuit, May 1, 2024

Ninth Circuit Court of Appeals grants Federal government’s petition for writ of mandamus in the case of Juliana v. United States, originally filed in 2015. Ruling excerpts are below in italics with my bolds. 20240501_docket-24-684_order

In the underlying case, twenty-one plaintiffs (the Juliana plaintiffs) claim that—by failing to adequately respond to the threat of climate change—the government has violated a putative “right to a stable climate system that can sustain human life.” Juliana v. United States, No. 6:15-CV-01517-AA, 2023 WL 9023339, at *1 (D. Or. Dec. 29, 2023). In a prior appeal, we held that the Juliana plaintiffs lack Article III standing to bring such a claim. Juliana v. United States, 947 F.3d 1159, 1175 (9th Cir. 2020). We remanded with instructions to dismiss on that basis. Id. The district court nevertheless allowed amendment, and the government again moved to dismiss. The district court denied that motion, and the government petitioned for mandamus seeking to enforce our earlier mandate. We have jurisdiction to consider the petition. See 28 U.S.C. § 1651. We grant it.

In the prior appeal, we held that declaratory relief was “not substantially likely to mitigate the plaintiffs’ asserted concrete injuries.” Juliana, 947 F.3d at 1170. To the contrary, it would do nothing “absent further court action,” which we held was unavailable. Id. We then clearly explained that Article III courts could not “step into the shoes” of the political branches to provide the relief the Juliana plaintiffs sought. Id. at 1175. Because neither the request for declaratory relief nor the request for injunctive relief was justiciable, we “remand[ed] th[e] case to the district court with instructions to dismiss for lack of Article III standing.” Id. Our mandate was to dismiss.

The district court gave two reasons for allowing amendment. First, it concluded that amendment was not expressly precluded. Second, it held that intervening authority compelled a different result. We reject each.
The first reason fails because we “remand[ed] . . . with instructions to dismiss for lack of Article III standing.” Id. Neither the mandate’s letter nor its spirit left room for amendment. See Pit River Tribe, 615 F.3d at 1079.
The second reason the district court identified was that, in its view, there was an intervening change in the law. District courts are not bound by a mandate when a subsequently decided case changes the law. In re Molasky, 843 F.3d 1179, 1184 n.5 (9th Cir. 2016). The case the court identified was Uzuegbunam v. Preczewski, which “ask[ed] whether an award of nominal damages by itself can redress a past injury.” 141 S. Ct. 792, 796 (2021). Thus, Uzuegbunam was a damages case which says nothing about the redressability of declaratory judgments. Damages are a form of retrospective relief. Buckhannon Bd. & Care Home v. W. Va. Dep’t of Health & Human Res., 532 U.S. 598, 608–09 (2001). Declaratory relief is prospective. The Juliana plaintiffs do not seek damages but seek only prospective relief. Nothing in Uzuegbunam changed the law with respect to prospective relief.

We held that the Juliana plaintiffs lack standing to bring their claims and told the district court to dismiss. Uzuegbunam did not change that. The district court is instructed to dismiss the case forthwith for lack of Article III standing, without leave to amend.

Background July 2023: Finally, a Legal Rebuttal on the Merits of Kids’ Climate Lawsuit

As reported last month, the Oregon activist judge invited the plaintiffs in Juliana vs US to reopen that case even after the Ninth Circuit shot it down. Now we have a complete and thorough Motion from the defendant (US government) to dismiss this newest amended complaint. Most interesting is the section under the heading starting on page 30. Excerpts in italics with my bolds and added images.

Plaintiffs’ Claims Fail on the Merits

Because Plaintiffs’ action fails at the jurisdictional threshold, the Ninth Circuit never reached—and this Court need not reach—the merits of the claims. . . Plaintiffs’ second amended complaint, which supersedes the first amended complaint, asserts the same claims that were brought in the first amended complaint, which this Court addressed in orders that the Ninth Circuit reversed. Defendants thus renew their objection that Plaintiffs’ claims fail on the merits and should be dismissed pursuant to Fed. R. Civ. P. 12(b)(6).

A. There is no constitutional right to a stable climate system.

The Supreme Court has repeatedly instructed courts considering novel due process claims
to “‘exercise the utmost care whenever . . . asked to break new ground in this field,’… lest the liberty protected by the Due Process Clause be subtly transformed” into judicial policy preferences. More specifically, the Supreme Court has “regularly observed that the Due Process Clause specially protects those fundamental rights and liberties which are, objectively, ‘deeply rooted in this Nation’s history and tradition.’” Plaintiffs’ request that this Court recognize an implied fundamental right to a stable climate system contradicts that directive, because such a purported right is without basis in the Nation’s history or tradition.

The proposed right to a “stable climate system” is nothing like any fundamental right ever recognized by the Supreme Court. The state of the climate is a public and generalized issue, and so interests in the climate are unlike the particularized personal liberty or personal privacy interests of individuals the Supreme Court has previously recognized as being protected by fundamental rights. “[W]henever federal courts have faced assertions of fundamental rights to a ‘healthful environment’ or to freedom from harmful contaminants, they have invariably rejected those claims.”. Plaintiffs’ First Claim for Relief must be dismissed.

B. Plaintiffs fail to allege a cognizable state-created danger claim.

The First Claim for Relief must also be dismissed because the Constitution does not impose an affirmative duty to protect individuals, and Plaintiffs have failed to allege a cognizable claim under the “state-created danger” exception to that rule.
As a general matter:

[The Due Process Clause] is phrased as a limitation on the State’s power to act, not as a guarantee of certain minimal levels of safety and security. It forbids the State itself to deprive individuals of life, liberty, or property without “due process of law,” but its language cannot fairly be extended to impose an affirmative obligation on the State to ensure that those interests do not come to harm through other means.

Thus, the Due Process Clause imposes no duty on the government to protect persons from harm inflicted by third parties that would violate due process if inflicted by the government.

Plaintiffs contend that the government’s “deliberate actions” and “deliberate indifference” with regard to the dangers of climate change amount to a due process violation under the state-created danger exception.

First, Plaintiffs have identified no harms to their “personal security or bodily integrity” of the kind and immediacy that qualify for the state-created danger exception. . . But here, Plaintiffs allege that general degradation of the global climate has harmed their “dignity, including their capacity to provide for their basic human needs, safely raise families, practice their religious and spiritual beliefs, [and] maintain their bodily integrity” and has prevented them from “lead[ing] lives with access to clean air, water, shelter, and food.” Those types of harm are unlike the immediate, direct, physical, and personal harms at issue in the above-cited cases.

Second, Plaintiffs identify no specific government actions—much less government actors—that put them in such danger. Instead, Plaintiffs contend that a number of (mostly unspecified) agency actions and inactions spanning the last several decades have exposed them to harm. This allegation of slowly-recognized, long-incubating, and generalized harm by itself conclusively distinguishes their claim from all other state-created danger cases recognized by the Ninth Circuit.

Third, Plaintiffs do not allege that government actions endangered Plaintiffs in particular. . . As explained above, Plaintiffs’ asserted injuries arise from a diffuse, global phenomenon that affects every other person in their communities, in the United States, and throughout the world.

For all these reasons, there is no basis for finding a violation of Plaintiffs’ due process right under the state-created danger doctrine, and Plaintiffs’ corresponding claim must be dismissed.

C. No federal public trust doctrine creates a right to a stable climate system.

Plaintiffs’ Fourth Claim for Relief, asserting public trust claims, should be dismissed for two independent reasons. First, any public trust doctrine is a creature of state law that applies narrowly and exclusively to particular types of state-owned property not at issue here. That doctrine has no application to federal property, the use and management of which is entrusted exclusively to Congress. . .Consequently, there is no basis for Plaintiffs’ public trust claim against the federal government under federal law.

Second, the “climate system” or atmosphere is not within any conceivable federal public trust.

1. No public trust doctrine binds the federal government.

Plaintiffs rely on an asserted public trust doctrine for the proposition that the federal government must “take affirmative steps to protect” “our country’s life-sustaining climate system,” which they assert the government holds in trust for their benefit. But because any public trust doctrine is a matter of state law only, public trust claims may not be asserted against the federal government under federal law. . . The Supreme Court has without exception treated public trust doctrine as a matter of state law with no basis in the United States Constitution.

2. Any public trust doctrine would not apply to the “climate system” or the atmosphere.

Independently, any asserted public trust doctrine does not help Plaintiffs here. Public trust cases have historically involved state ownership of specific types of natural resources, usually limited to submerged and submersible lands, tidelands, and waterways. . . The climate system or atmosphere is unlike any resource previously deemed subject to a public trust. It cannot be owned and, due to its ephemeral nature, cannot remain within the jurisdiction of any single government. No court has held that the climate system or atmosphere is protected by a public trust doctrine. Indeed, the concept has been widely rejected.

For all these reasons, the Court should dismiss Plaintiffs’ Fourth Claim for Relief.

Background Post Update on Zombie Kids Climate Lawsuits: (Juliana vs. US) (Held vs Montana)

April 2025 Two Years Ocean Warming Gone

Posted on May 23 by Ron Clutz

The best context for understanding decadal temperature changes comes from the world’s sea surface temperatures (SST), for several reasons:

The ocean covers 71% of the globe and drives average temperatures;
SSTs have a constant water content, (unlike air temperatures), so give a better reading of heat content variations;
A major El Nino was the dominant climate feature in recent years.

HadSST is generally regarded as the best of the global SST data sets, and so the temperature story here comes from that source. Previously I used HadSST3 for these reports, but Hadley Centre has made HadSST4 the priority, and v.3 will no longer be updated. HadSST4 is the same as v.3, except that the older data from ship water intake was re-estimated to be generally lower temperatures than shown in v.3. The effect is that v.4 has lower average anomalies for the baseline period 1961-1990, thereby showing higher current anomalies than v.3. This analysis concerns more recent time periods and depends on very similar differentials as those from v.3 despite higher absolute anomaly values in v.4. More on what distinguishes HadSST3 and 4 from other SST products at the end. The user guide for the current version HadSST4.1.1.0 is here. The charts and analysis below is produced from the current data.

The Current Context

The chart below shows SST monthly anomalies as reported in HadSST4 starting in 2015 through April 2025. A global cooling pattern is seen clearly in the Tropics since its peak in 2016, joined by NH and SH cycling downward since 2016, followed by rising temperatures in 2023 and 2024.

Note that in 2015-2016 the Tropics and SH peaked in between two summer NH spikes. That pattern repeated in 2019-2020 with a lesser Tropics peak and SH bump, but with higher NH spikes. By end of 2020, cooler SSTs in all regions took the Global anomaly well below the mean for this period. A small warming was driven by NH summer peaks in 2021-22, but offset by cooling in SH and the tropics, By January 2023 the global anomaly was again below the mean.

Then in 2023-24 came an event resembling 2015-16 with a Tropical spike and two NH spikes alongside, all higher than 2015-16. There was also a coinciding rise in SH, and the Global anomaly was pulled up to 1.1°C last year, ~0.3° higher than the 2015 peak. Then NH started down autumn 2023, followed by Tropics and SH descending 2024 to the present. After 12 months of cooling in SH and the Tropics, the Global anomaly came back down, led by NH cooling the last 8 months from its 1.3C peak in August, down to 0.8C in March and April. With some recent warming in the Tropics and SH, all regions are now close together nearly at the global anomaly, less than 0.1C higher than the average for this period.

Remarkably, April 2025 SST anomalies in all regions and globally are the coolest since March 2023.

Comment:

The climatists have seized on this unusual warming as proof their Zero Carbon agenda is needed, without addressing how impossible it would be for CO2 warming the air to raise ocean temperatures. It is the ocean that warms the air, not the other way around. Recently Steven Koonin had this to say about the phonomenon confirmed in the graph above:

El Nino is a phenomenon in the climate system that happens once every four or five years. Heat builds up in the equatorial Pacific to the west of Indonesia and so on. Then when enough of it builds up it surges across the Pacific and changes the currents and the winds. As it surges toward South America it was discovered and named in the 19th century It iswell understood at this point that the phenomenon has nothing to do with CO2.

Now people talk about changes in that phenomena as a result of CO2 but it’s there in the climate system already and when it happens it influences weather all over the world. We feel it when it gets rainier in Southern California for example. So for the last 3 years we have been in the opposite of an El Nino, a La Nina, part of the reason people think the West Coast has been in drought.

It has now shifted in the last months to an El Nino condition that warms the globe and is thought to contribute to this Spike we have seen. But there are other contributions as well. One of the most surprising ones is that back in January of 2022 an enormous underwater volcano went off in Tonga and it put up a lot of water vapor into the upper atmosphere. It increased the upper atmosphere of water vapor by about 10 percent, and that’s a warming effect, and it may be that is contributing to why the spike is so high.

A longer view of SSTs

The graph below is noisy, but the density is needed to see the seasonal patterns in the oceanic fluctuations. Previous posts focused on the rise and fall of the last El Nino starting in 2015. This post adds a longer view, encompassing the significant 1998 El Nino and since. The color schemes are retained for Global, Tropics, NH and SH anomalies. Despite the longer time frame, I have kept the monthly data (rather than yearly averages) because of interesting shifts between January and July.

To enlarge image, open in new tab.

The graph above is noisy, but the density is needed to see the seasonal patterns in the oceanic fluctuations. Previous posts focused on the rise and fall of the last El Nino starting in 2015. This post adds a longer view, encompassing the significant 1998 El Nino and since. The color schemes are retained for Global, Tropics, NH and SH anomalies. Despite the longer time frame, I have kept the monthly data (rather than yearly averages) because of interesting shifts between January and July. 1995 is a reasonable (ENSO neutral) starting point prior to the first El Nino.

The sharp Tropical rise peaking in 1998 is dominant in the record, starting Jan. ’97 to pull up SSTs uniformly before returning to the same level Jan. ’99. There were strong cool periods before and after the 1998 El Nino event. Then SSTs in all regions returned to the mean in 2001-2.

SSTS fluctuate around the mean until 2007, when another, smaller ENSO event occurs. There is cooling 2007-8, a lower peak warming in 2009-10, following by cooling in 2011-12. Again SSTs are average 2013-14.

Now a different pattern appears. The Tropics cooled sharply to Jan 11, then rise steadily for 4 years to Jan 15, at which point the most recent major El Nino takes off. But this time in contrast to ’97-’99, the Northern Hemisphere produces peaks every summer pulling up the Global average. In fact, these NH peaks appear every July starting in 2003, growing stronger to produce 3 massive highs in 2014, 15 and 16. NH July 2017 was only slightly lower, and a fifth NH peak still lower in Sept. 2018.

The highest summer NH peaks came in 2019 and 2020, only this time the Tropics and SH were offsetting rather adding to the warming. (Note: these are high anomalies on top of the highest absolute temps in the NH.) Since 2014 SH has played a moderating role, offsetting the NH warming pulses. After September 2020 temps dropped off down until February 2021. In 2021-22 there were again summer NH spikes, but in 2022 moderated first by cooling Tropics and SH SSTs, then in October to January 2023 by deeper cooling in NH and Tropics.

Then in 2023 the Tropics flipped from below to well above average, while NH produced a summer peak extending into September higher than any previous year. Despite El Nino driving the Tropics January 2024 anomaly higher than 1998 and 2016 peaks, following months cooled in all regions, and the Tropics continued cooling in April, May and June along with SH dropping. After July and August NH warming again pulled the global anomaly higher, September through January 2025 resumed cooling in all regions, continuing February through April 2025.

What to make of all this? The patterns suggest that in addition to El Ninos in the Pacific driving the Tropic SSTs, something else is going on in the NH. The obvious culprit is the North Atlantic, since I have seen this sort of pulsing before. After reading some papers by David Dilley, I confirmed his observation of Atlantic pulses into the Arctic every 8 to 10 years.

Contemporary AMO Observations

Through January 2023 I depended on the Kaplan AMO Index (not smoothed, not detrended) for N. Atlantic observations. But it is no longer being updated, and NOAA says they don’t know its future. So I find that ERSSTv5 AMO dataset has current data. It differs from Kaplan, which reported average absolute temps measured in N. Atlantic. “ERSST5 AMO follows Trenberth and Shea (2006) proposal to use the NA region EQ-60°N, 0°-80°W and subtract the global rise of SST 60°S-60°N to obtain a measure of the internal variability, arguing that the effect of external forcing on the North Atlantic should be similar to the effect on the other oceans.” So the values represent SST anomaly differences between the N. Atlantic and the Global ocean.

The chart above confirms what Kaplan also showed. As August is the hottest month for the N. Atlantic, its variability, high and low, drives the annual results for this basin. Note also the peaks in 2010, lows after 2014, and a rise in 2021. Then in 2023 the peak was holding at 1.4C before declining. An annual chart below is informative:

Note the difference between blue/green years, beige/brown, and purple/red years. 2010, 2021, 2022 all peaked strongly in August or September. 1998 and 2007 were mildly warm. 2016 and 2018 were matching or cooler than the global average. 2023 started out slightly warm, then rose steadily to an extraordinary peak in July. August to October were only slightly lower, but by December cooled by ~0.4C.

Then in 2024 the AMO anomaly started higher than any previous year, then leveled off for two months declining slightly into April. Remarkably, May showed an upward leap putting this on a higher track than 2023, and rising slightly higher in June. In July, August and September 2024 the anomaly declined, and despite a small rise in October, ended close to where it began. Note 2025 started much lower than the previous year and is headed sharply downward, well below the previous two years.

The pattern suggests the ocean may be demonstrating a stairstep pattern like that we have also seen in HadCRUT4.

The purple line is the average anomaly 1980-1996 inclusive, value 0.17. The orange line the average 1980-2024, value 0.38, also for the period 1997-2012. The red line is 2013-2024, value 0.67. As noted above, these rising stages are driven by the combined warming in the Tropics and NH, including both Pacific and Atlantic basins.

Curiosity: Solar Coincidence?

The news about our current solar cycle 25 is that the solar activity is hitting peak numbers now and higher than expected 1-2 years in the future. As livescience put it: Solar maximum could hit us harder and sooner than we thought. How dangerous will the sun’s chaotic peak be? Some charts from spaceweatherlive look familar to these sea surface temperature charts.

Summary

The oceans are driving the warming this century. SSTs took a step up with the 1998 El Nino and have stayed there with help from the North Atlantic, and more recently the Pacific northern “Blob.” The ocean surfaces are releasing a lot of energy, warming the air, but eventually will have a cooling effect. The decline after 1937 was rapid by comparison, so one wonders: How long can the oceans keep this up? And is the sun adding forcing to this process?

Footnote: Why Rely on HadSST4

HadSST is distinguished from other SST products because HadCRU (Hadley Climatic Research Unit) does not engage in SST interpolation, i.e. infilling estimated anomalies into grid cells lacking sufficient sampling in a given month. From reading the documentation and from queries to Met Office, this is their procedure.

HadSST4 imports data from gridcells containing ocean, excluding land cells. From past records, they have calculated daily and monthly average readings for each grid cell for the period 1961 to 1990. Those temperatures form the baseline from which anomalies are calculated.

In a given month, each gridcell with sufficient sampling is averaged for the month and then the baseline value for that cell and that month is subtracted, resulting in the monthly anomaly for that cell. All cells with monthly anomalies are averaged to produce global, hemispheric and tropical anomalies for the month, based on the cells in those locations. For example, Tropics averages include ocean grid cells lying between latitudes 20N and 20S.

Gridcells lacking sufficient sampling that month are left out of the averaging, and the uncertainty from such missing data is estimated. IMO that is more reasonable than inventing data to infill. And it seems that the Global Drifter Array displayed in the top image is providing more uniform coverage of the oceans than in the past.

uss-pearl-harbor-deploys-global-drifter-buoys-in-pacific-ocean

USS Pearl Harbor deploys Global Drifter Buoys in Pacific Ocean

IPCC Climate Models Proven to Lack Predictive Ability

Posted on May 22 by Ron Clutz

The recently published paper is Are Climate Model Forecasts Useful for Policy Making? by Kesten C. Green and Willie Soon. Excerpts in italics with my bolds and added images.

Effect of Variable Choice on Reliability and Predictive Validity

Abstract

For a model to be useful for policy decisions, statistical fit is insufficient. Evidence that the model provides out-of-estimation-sample forecasts that are more accurate and reliable than those from plausible alternative models, including a simple benchmark, is necessary.

The UN’s IPCC advises governments with forecasts of global average temperature drawn from models based on hypotheses of causality. Specifically, manmade warming principally from carbon dioxide emissions (Anthro) tempered by the effects of volcanic eruptions (Volcanic) and by variations in the Sun’s energy (Solar). Out-of-sample forecasts from that model, with and without the IPCC’s favoured measure of Solar, were compared with forecasts from models that excluded human influence and included Volcanic and one of two independent measures of Solar. The models were used to forecast Northern Hemisphere land temperatures and—to avoid urban heat island effects—rural only temperatures. Benchmark forecasts were obtained by extrapolating estimation sample median temperatures.

The independent solar models reduced forecast errors relative to those of the benchmark model for all eight combinations of four estimation periods and the two temperature variables tested. The models that included the IPCC’s Anthro variable reduced errors for only three of the eight combinations and produced extreme forecast errors from most model estimation periods. The correlation between estimation sample statistical fit and forecast accuracy was -0.26. Further tests might identify better models: Only one extrapolation model and only two of many possible independent solar models were tested, and combinations of forecasts from different methods were not examined.

The anthropogenic models’ unreliability would appear to void policy relevance. In practice, even the models validated in this study may fail to improve accuracy relative to naïve forecasts due to uncertainty over the future causal variable values. Our findings emphasize that out-of-sample forecast errors, not statistical fit, should be used to choose between models (hypotheses).

Background

In their attempts to achieve the IPCC objective of identifying a human cause for temperature changes—specifically “global warming”—the IPCC researchers have framed the problem as one of “attributing” changes in the Earth’s temperature to the respective contributions of putative anthropogenic (“Anthro”) principally carbon dioxide emissions altering the composition of the atmosphere—and natural influences—principally aerosols from volcanic eruptions altering the composition of the atmosphere (“Volcanic”), and total solar irradiance, or TSI, variations (“Solar”).

Given the task they were set, the IPCC researchers have devoted
much of their efforts into developing estimates of the Anthro variable.

The IPCC’s most recent, AR6, report (IPCC, 2021) only considered one estimate of Solar for the purpose of attribution (Matthes et al., 2017) and made no allowance for the effect of urban heat islands on the temperature measures they used (Connolly et al., 2021, 2023; Soon et al., 2023). Moreover, a study of the statistical attribution or “fingerprinting” approach used by IPCC researchers (e.g., Allen and Tett, 1999; Hasselmann, et al., 1995; Hegerl et al., 1997; Santer et al.,1995) concluded that the approach was invalid (McKitrick, 2022). The IPCC authors’ analyses failed to meet the assumptions of the method they used, and they failed to correctly implement the method.

In sum, the objective given to the IPCC researchers and the approach that they have taken suggests that plausible alternative hypotheses on the causes of terrestrial temperature changes may not have been adequately tested, as is required by the scientific method (Armstrong and Green, 2022). That concern is consistent with Armstrong and Green’s (2022) observation that government sponsorship of research can create incentives that may influence researchers’ choices of hypotheses to test and how they test them.

1.1 Alternative hypotheses on Solar

To address the first of the foregoing limitations in the IPCC attribution studies—failure to fairly test alternative TSI estimates—Connolly et al. (2021, 2023) comprehensively reviewed alternative estimates of TSI covering the 169 years from 1850 to 2018. In addition to the Matthes, et al. (2017) TSI estimates series used by the IPCC (2021)—henceforth “IPCC Solar”—Connolly et al. (2023) identified 27 alternative Solar time series.

The alternative estimates of Solar correlate quite well with the TSI used in the AR6 report—Pearson’s r values range between 0.39 and 0.97 with a median of 0.82—but the degree of TSI variation in Watts per square metre (Wm-2) differs considerably between the estimates. The ranges of the individual alternative TSI estimate series vary between 0.49 and 4.64 Wm-2, with a median range of 1.77 Wm-2, while IPCC Solar has a range of only 0.19 Wm-2.

In this study, we consider two plausible TSI reconstructions from Connolly et al. (2023). Those from Hoyt and Schatten (1993) and from Bard et al. (2000), which Connolly et al. (2023) updated to the year 20182. The former TSI record (“H1993 Solar”) was based on the so-called multiproxy—i.e., equatorial solar rotation rate, sunspot structure, the decay rate of individual sunspots, the number of sunspots without umbrae, and the length and decay rate of the 11-yr sunspot activity cycle—reconstruction of the solar irradiance history.

1.2 Alternative hypotheses on temperature estimation

The IPCC’s attribution studies do not account for the direct effects of human activities on local temperatures (heat islands)—the second weakness addressed in this study. For example, heating and cooling of building interiors, electricity generation, manufacturing, freight and transport, asphalt and concrete, and where vegetation and open water have been removed or added. Where temperature readings are taken close to such human sources of heat or absence of natural cooling, they cannot properly reflect the individual effects of human emissions of carbon dioxide, etc., that the IPCC are concerned about (their Anthro variable), the Volcanic variable, and TSI.

To address this second limitation in the IPCC attribution studies, Connolly et al. (2021, 2023) developed four alternative estimates of surface temperatures that were intended to avoid heat island effects. They were based on rural only weather station readings, sea surface temperature readings, tree-ring width measurements, and glacier length measurements. For comparison with the approach used by the IPCC, they also developed an all-land temperature estimates series for the Northern Hemisphere.

1.5 Hypotheses tested

The foregoing discussion suggests the following hypotheses, which are tested in this study.

- H1. Forecasts from causal models will [will not] be usefully more accurate than forecasts from a naïve no-change model.
- H2. Models using variable measures developed independently of the IPCC dangerous manmade global warming hypothesis will [will not] have greater predictive validity.
- H3. The statistical fit of the models (adjusted-R2) will not [will] be substantively positively related to their predictive validity.
- H4. Models using variable measures developed independently of the IPCC dangerous manmade global warming hypothesis will [will not] be more reliable.

Findings

Figure 1: Absolute Errors of NH All Land and Rural Land Temperature Forecasts to 2018 (℃) — Forecasts from four alternative models plus naïve estimates over four periods. Legend (Causal variables in models): Black Anthro, Volcanic; Red Anthro, Volcanic, IPCC Solar; Green B2000 Solar, Volcanic; Blue H1993 Solar, Volcanic; Yellow Estimation sample median temperature.

3.1 Predictive validity of causal models versus naïve model [H1]

Forecast errors were larger than the benchmark errors (UMBRAE) for the IPCC Anthro models AVL and AVSL estimated with data from 1850 to 1949 and from 1850 to 1969, and for the AVR and AVSR models estimated with data from 1850 to 1899, 1850 to 1949, and 1850 to 1969. The anthropogenic warming models showed predictive validity relative the naïve model (UMBRAE less than 1.0) for only three of the eight combinations of forecast variable and estimation sample period.

3.2 Predictive validity of independent versus IPCC models [H2]

The MdAEs (median absolute error) of the forecasts from the models with IPCC’s anthropogenic and volcanic series as causal variables (AVL and AVR) and from the models that also included IPCC’s solar series (AVSL and AVSR) were greater than 1°C (roughly 2°F) for five of the eight combinations tested. The MdAEs of the forecasts from the models with B2000 solar and the volcanic series as causal variables (SBVL and SBVR) were less than 0.55°C (1°F) for all eight of the estimation periods used and temperature series being forecast combinations and for seven of the eight in the case of the models with H1993 as the solar variable (SHVL and SHVR).

3.3 Relationship between predictive validity and statistical fit of models [H3]

The correlations (sign-reversed Pearson’s r) between the accuracy of out-of-sample forecasts, as measured by UMBRAE (an error measure, hence the sign reversal), and the statistical fit of the models to the estimation data (adjusted-R2) for the causal models tested were large and negative for six (6) of the eight (8) combinations of estimation period (1850 to 1899, 1949, 1969, and 1999) used—and hence maximum forecast horizon of 119, 69, 49, and 19 years, respectively—and temperature series (NH Land and NH Rural) forecast.

3.4 Reliability of independent versus IPCC models [H4]

Charts of the results of Test 2 are presented in Figure 2 and are discussed below.

Figure 2. Median absolute errors of NH temperature forecasts 2000 to 2018 in ℃. Legend (Causal variables in models): Black Anthro, Volcanic; Red Anthro, Volcanic, IPCC Solar; Green B2000 Solar, Volcanic; Blue H1993 Solar, Volcanic; Yellow Estimation sample median temperature.

The independent solar models—SBVL and SHVL, and SBVR and SHVR—perform largely as one
would expect of causal models when forecasting using known values of the causal variables.

In the case of the AVR and AVSR models—forecasting the rural land temperatures, on the right of Figure 2—the MdAEs decreased rapidly from roughly 17 times the corresponding naïve forecast errors to beat the naïve MdAE when the 76th observation (1925) was added to the estimation samples. After that observation was added, the MdAEs for the AVR and AVSR model forecasts increased rapidly with each extra observation then stayed high before rapidly declining again after the 116th observation (1965) was added to the estimation samples.

When a model of causal relationships is estimated from empirical data on valid causal variables reliably measured, one would expect forecast errors to get smaller as more observations are used in the estimation of the model’s parameters. That is what the charts in Figure 2 show in the case of the naïve benchmark model forecasts and, broadly, what can be seen in the case of the independent models SBVL, SHVL, SBVR, and SHVR, but is not seen in the case of the models using the IPCC variables: AVL, AVSL, AVR, and AVSR.

The errors of the Anthro models’ forecast errors explode well beyond 1 °C and the benchmark model errors for forecast years beyond the mid-1970s, with puzzling exceptions. Namely, forecasts from Anthro models estimated from the largest sample size in the chart—1850 to 1999—and from models estimated from the smallest sample—1850 to 1899—forecasting All Land temperatures. In those cases, involving three of the eight charts, the Anthro model errors are less than the median historical temperature benchmark model errors, and mostly less than the errors of the independent models in later years.

The explosion in Anthro model errors from the 1970s is more extreme for models estimated to forecast Rural Land temperatures. Moreover, for the models estimated using only 1850 to 1899 data, errors are larger than those of the benchmark and independent models from 1920 and, prior to 1970, without any obvious pattern.

5. Conclusions

The IPCC’s models of anthropogenic climate change lack predictive validity. The IPCC models’ forecast errors were greater for most estimation samples —often many times greater—than those from a benchmark model that simply predicts that future years’ temperatures will be the same as the historical median. The size of the forecast errors and unreliability of the models’ forecasts in response to additional observations in the estimation sample implies that the anthropogenic models fail to realistically capture and represent the causes of Earth’s surface temperature changes. In practice, the IPCC models’ relative forecast errors would be still greater due to the uncertainty in forecasting the models’ causal variables, particularly Volcanic and IPCC Solar.

The independent solar models of climate change—which did not include a variable representing the IPCC postulated anthropogenic influence—do have predictive validity. The models reduced errors of forecasts for the years 2000 to 2018 relative to the benchmark errors for all, and all but one of 101 estimation samples tested for each of the two models. One of the models (B2000 Solar) reduced errors by more than 75 percent for forecasts from models estimated from 35 of the samples—a particularly impressive improvement given that the benchmark errors were no greater than 1 °C for all but one of the estimation samples.

The independent solar models provide realistic representations of the causal relationships with surface temperatures. The question of whether the independent solar variables can be forecast with sufficient accuracy to improve on the benchmark model forecasts in practice, however, remains relevant. All in all, and contra to the IPCC reports, there is insufficient evidential basis for the use of carbon dioxide, et cetera, emissions—taken together, the IPCC’s Anthro—as climate policy variables.

Finally, this study provides further evidence that measures of statistical fit provide misinformation about predictive validity. Predictive validity can only be properly estimated when the proposed model or hypothesis is used for forecasting new-to-the-model data, and the forecasts are then compared for accuracy against forecasts from a plausible benchmark model. This important conclusion needs bearing in mind when evaluating policy models.

See Also:

Lacking Data, Climate Models Rely on Guesses

Figure 1. Anthropgenic and natural contributions. (a) Locked scaling factors,
weak Pre Industrial Climate Anomalies (PCA). (b) Free scaling, strong PCA

Climate Models Hide the Paleo Incline

April 2025 UAH Temps Little Changed For Now

Posted on May 21 by Ron Clutz

The post below updates the UAH record of air temperatures over land and ocean. Each month and year exposes again the growing disconnect between the real world and the Zero Carbon zealots. It is as though the anti-hydrocarbon band wagon hopes to drown out the data contradicting their justification for the Great Energy Transition. Yes, there was warming from an El Nino buildup coincidental with North Atlantic warming, but no basis to blame it on CO2.

As an overview consider how recent rapid cooling completely overcame the warming from the last 3 El Ninos (1998, 2010 and 2016). The UAH record shows that the effects of the last one were gone as of April 2021, again in November 2021, and in February and June 2022 At year end 2022 and continuing into 2023 global temp anomaly matched or went lower than average since 1995, an ENSO neutral year. (UAH baseline is now 1991-2020). Then there was an usual El Nino warming spike of uncertain cause, unrelated to steadily rising CO2 and now dropping steadily.

For reference I added an overlay of CO2 annual concentrations as measured at Mauna Loa. While temperatures fluctuated up and down ending flat, CO2 went up steadily by ~60 ppm, a 15% increase.

Furthermore, going back to previous warmings prior to the satellite record shows that the entire rise of 0.8C since 1947 is due to oceanic, not human activity.

gmt-warming-events

The animation is an update of a previous analysis from Dr. Murry Salby. These graphs use Hadcrut4 and include the 2016 El Nino warming event. The exhibit shows since 1947 GMT warmed by 0.8 C, from 13.9 to 14.7, as estimated by Hadcrut4. This resulted from three natural warming events involving ocean cycles. The most recent rise 2013-16 lifted temperatures by 0.2C. Previously the 1997-98 El Nino produced a plateau increase of 0.4C. Before that, a rise from 1977-81 added 0.2C to start the warming since 1947.

Importantly, the theory of human-caused global warming asserts that increasing CO2 in the atmosphere changes the baseline and causes systemic warming in our climate. On the contrary, all of the warming since 1947 was episodic, coming from three brief events associated with oceanic cycles. And in 2024 we saw an amazing episode with a temperature spike driven by ocean air warming in all regions, along with rising NH land temperatures, now dropping below its peak.

Chris Schoeneveld has produced a similar graph to the animation above, with a temperature series combining HadCRUT4 and UAH6. H/T WUWT

April 2025 UAH Temps Little Changed Despite Tropical Cooling

With apologies to Paul Revere, this post is on the lookout for cooler weather with an eye on both the Land and the Sea. While you heard a lot about 2020-21 temperatures matching 2016 as the highest ever, that spin ignores how fast the cooling set in. The UAH data analyzed below shows that warming from the last El Nino had fully dissipated with chilly temperatures in all regions. After a warming blip in 2022, land and ocean temps dropped again with 2023 starting below the mean since 1995. Spring and Summer 2023 saw a series of warmings, continuing into 2024 peaking in April, then cooling off to the present.

UAH has updated their TLT (temperatures in lower troposphere) dataset for April 2025. Due to one satellite drifting more than can be corrected, the dataset has been recalibrated and retitled as version 6.1 Graphs here contain this updated 6.1 data. Posts on their reading of ocean air temps this month are ahead of the update from HadSST4. I posted recently on SSTs March 2025 Oceans Cooling Persists. These posts have a separate graph of land air temps because the comparisons and contrasts are interesting as we contemplate possible cooling in coming months and years.

Sometimes air temps over land diverge from ocean air changes. In July 2024 all oceans were unchanged except for Tropical warming, while all land regions rose slightly. In August we saw a warming leap in SH land, slight Land cooling elsewhere, a dip in Tropical Ocean temp and slightly elsewhere. September showed a dramatic drop in SH land, overcome by a greater NH land increase. 2025 has shown a sharp contrast between land and sea, first with ocean air temps falling in January recovering in February. Then land air temps, especially NH, dropped in February and recovered in March.

Note: UAH has shifted their baseline from 1981-2010 to 1991-2020 beginning with January 2021. v6.1 data was recalibrated also starting with 2021. In the charts below, the trends and fluctuations remain the same but the anomaly values changed with the baseline reference shift.

Presently sea surface temperatures (SST) are the best available indicator of heat content gained or lost from earth’s climate system. Enthalpy is the thermodynamic term for total heat content in a system, and humidity differences in air parcels affect enthalpy. Measuring water temperature directly avoids distorted impressions from air measurements. In addition, ocean covers 71% of the planet surface and thus dominates surface temperature estimates. Eventually we will likely have reliable means of recording water temperatures at depth.

Recently, Dr. Ole Humlum reported from his research that air temperatures lag 2-3 months behind changes in SST. Thus cooling oceans portend cooling land air temperatures to follow. He also observed that changes in CO2 atmospheric concentrations lag behind SST by 11-12 months. This latter point is addressed in a previous post Who to Blame for Rising CO2?

After a change in priorities, updates are now exclusive to HadSST4. For comparison we can also look at lower troposphere temperatures (TLT) from UAHv6.1 which are now posted for April 2025. The temperature record is derived from microwave sounding units (MSU) on board satellites like the one pictured above. Recently there was a change in UAH processing of satellite drift corrections, including dropping one platform which can no longer be corrected. The graphs below are taken from the revised and current dataset.

The UAH dataset includes temperature results for air above the oceans, and thus should be most comparable to the SSTs. There is the additional feature that ocean air temps avoid Urban Heat Islands (UHI). The graph below shows monthly anomalies for ocean air temps since January 2015.

In 2021-22, SH and NH showed spikes up and down while the Tropics cooled dramatically, with some ups and downs, but hitting a new low in January 2023. At that point all regions were more or less in negative territory.

After sharp cooling everywhere in January 2023, there was a remarkable spiking of Tropical ocean temps from -0.5C up to + 1.2C in January 2024. The rise was matched by other regions in 2024, such that the Global anomaly peaked at 0.86C in April. Since then all regions have cooled down sharply to a low of 0.27C in January. In February 2025, SH rose from 0.1C to 0.4C pulling the Global ocean air anomaly up to 0.47C, where it stayed in March and April

Land Air Temperatures Tracking in Seesaw Pattern

We sometimes overlook that in climate temperature records, while the oceans are measured directly with SSTs, land temps are measured only indirectly. The land temperature records at surface stations sample air temps at 2 meters above ground. UAH gives tlt anomalies for air over land separately from ocean air temps. The graph updated for March is below.

Here we have fresh evidence of the greater volatility of the Land temperatures, along with extraordinary departures by SH land. The seesaw pattern in Land temps is similar to ocean temps 2021-22, except that SH is the outlier, hitting bottom in January 2023. Then exceptionally SH goes from -0.6C up to 1.4C in September 2023 and 1.8C in August 2024, with a large drop in between. In November, SH and the Tropics pulled the Global Land anomaly further down despite a bump in NH land temps. February showed a sharp drop in NH land air temps from 1.07C down to 0.56C, pulling the Global land anomaly downward from 0.9C to 0.6C. In March that drop reversed with both NH and Global land back to January values, despite another drop in SH land air temps. Now in April there is a slight upward bump despite a dip in Tropical land temperatures

The Bigger Picture UAH Global Since 1980

The chart shows monthly Global Land and Ocean anomalies starting 01/1980 to present. The average monthly anomaly is -0.03, for this period of more than four decades. The graph shows the 1998 El Nino after which the mean resumed, and again after the smaller 2010 event. The 2016 El Nino matched 1998 peak and in addition NH after effects lasted longer, followed by the NH warming 2019-20. An upward bump in 2021 was reversed with temps having returned close to the mean as of 2/2022. March and April brought warmer Global temps, later reversed

With the sharp drops in Nov., Dec. and January 2023 temps, there was no increase over 1980. Then in 2023 the buildup to the October/November peak exceeded the sharp April peak of the El Nino 1998 event. It also surpassed the February peak in 2016. In 2024 March and April took the Global anomaly to a new peak of 0.94C. The cool down started with May dropping to 0.9C, and in June a further decline to 0.8C. October went down to 0.7C, November and December dropped to 0.6C. February went down to 0.5C, then back up to 0.6C in March and April driven by the bounce in NH land air temps.

The graph reminds of another chart showing the abrupt ejection of humid air from Hunga Tonga eruption.

Note on Ocean Cooling Not Fully Appearing in UAH Dataset

The above chart shows sea surface temperature anomalies (SSTA) in the North Atlantic 0 to 60N. The index is derived from ERSSTv.5 by subtracting the global anomalies from the North Atlantic anomalies, the differences as shown in the chart. The baseline of 0.0C is the average for the years 1951 to 1980. The mean anomaly since 1980 is in purple at 0.33C, and persisted throughout up to 2018. The orange line is the average anomaly in the the last six years, 2019 to 04/2025 inclusive, at 0.84C. The remarkable spikes in 2023 and 2024 drove that rise to exceed 1.4C, which has been cut in half over the last 10 months. As Dr. Humlum observed, such oceanic changes usually portend air temperature changes later on.

TLTs include mixing above the oceans and probably some influence from nearby more volatile land temps. Clearly NH and Global land temps have been dropping in a seesaw pattern, nearly 1C lower than the 2016 peak. Since the ocean has 1000 times the heat capacity as the atmosphere, that cooling is a significant driving force. TLT measures started the recent cooling later than SSTs from HadSST4, but are now showing the same pattern. Despite the three El Ninos, their warming had not persisted prior to 2023, and without them it would probably have cooled since 1995. Of course, the future has not yet been written.

It’s the Sun Warming Us, Dummy

Posted on April 25 by Ron Clutz

Nir Shaviv makes sense in his Daily Sceptic article Global Warming is Mostly Caused By the Sun, Not Humans, Says Astrophysics Professor. Excerpts in italics with my bolds and added images.

“There’s no such thing as a scientific consensus,” Nir Shaviv, a Professor at the Racah Institute of Physics at the Hebrew University of Jerusalem says in response to a question about what he thinks of the widespread claim that there is a scientific consensus on the anthropogenic nature of climate change. “In science, we deal with open questions and I think that the question of climate change is an open question. There are a lot of things which many scientists are still arguing about,” he explains.

Indeed, there are scientists who say that climate change is caused entirely by humans and the situation is very dire. But then there are those who say that although humans are causing much of the warming, the situation is not as bad as we are being told by politicians and activists through the media. Some think that CO₂ plays an important part in the current warming trend and some believe its role is insignificant.

Although Shaviv assesses that some of the warming in the 20th century is indeed the result of increasing atmospheric CO₂ concentrations, most of the change is a natural phenomenon. “My research has led me to strongly believe that based on all the evidence that’s accumulated over the past around 25 years, a large part of the warming is actually not because of humans, but because of the solar effect,” he says.

Up to two-thirds of the warming comes from the Sun

As an astrophysicist, Shaviv’s research has largely focused on understanding how solar activity and the Earth’s climate are linked. In fact, he says, at least half, and possibly two-thirds, of the 20th century’s warming is related to increased solar activity. Shaviv has also shown that cosmic rays and their activity influence cloud cover formation, also causing the climate to change. He has been working on this issue together with Danish astrophysicist Dr Henrik Svensmark.

In any case, Shaviv says, if solar activity and cosmic ray effects are taken into account, the climate sensitivity remains relatively low, or simply put – an increase in the proportion of CO₂ in the atmosphere cannot cause much warming. Scientists have long attempted to calculate how much a doubling of atmospheric CO₂ would raise the temperature of the Earth. The first attempt was made more than 100 years ago by the Swedish chemist Svante Arrhenius, who suggested an answer of up to six degrees Celsius. Since then, this number has been revised downwards, but not enough, according to Shaviv. “If you open the IPCC [Intergovernmental Panel on Climate Change] reports, then the canonical range is anywhere between one and a half or two, depending on which report you look at, to maybe four and a half degrees increase for CO₂ doubling. What I find is that climate sensitivity is somewhere between one and one and a half degree increase per CO₂ doubling,” Shaviv says, adding that he does not expect the temperature rise in the 21st century to be very high.

On average, half of sunlight is either absorbed in the atmosphere or reflected before it can be absorbed by the surface land and ocean. Any shift in the reflectivity (albedo) impacts greatly on the solar energy warming the planet.

Explaining the warming that has happened primarily with CO₂ is where the IPCC’s scientific reports err, Shaviv says, by failing to account for the solar effect. And because they do not account for it, but there is still a need to explain the temperature rise, the rise in CO₂ levels in the atmosphere, which has been attributed to human influences, has been used to explain it. Shaviv explains that this is the wrong answer as it fails to take into account all the contributing factors.

Is the planet boiling?

But is this temperature rise causing a climate crisis? Shaviv’s answer to the question is simple and clear: “No.” He explains that the average temperature on the planet has risen by one degree Celsius since about 1900, but this is not unprecedented. We are familiar, for example, with the Medieval Warm Period, when the Vikings charted the coast of Greenland, including its northern part, which today is covered with ice even in summer. “This kind of climate variation has always happened. Some of the warming now is anthropogenic, but it’s not a crisis in the sense that the temperature is going to increase by five degrees in a century and we’re all doomed. We just have to adapt to changes. Some of them are natural and some are not, but they’re not large,” Shaviv explains.

It has been widely reported that both 2023 and 2024 were the warmest years on record. Referring to this rise in temperatures, UN Secretary-General António Guterres already in July 2023 declared that we have entered an “era of global boiling”. Shaviv says that of course, we can have average surface temperatures that are highest if we only look back 100 or 150 years. “If you go back a thousand years it was just as warm. If you go back 5,000 years it was definitely warmer. So, It doesn’t mean much,” he explains.

And if you look at a longer time scale, warmer periods have alternated with colder periods throughout. Also, over the last 100,000 years, the Earth has been in an ice age for most of that time, and the retreat of the ice in Europe and North America happened about 12,000 years ago.

Do extreme weather events prove a climate crisis?

However, it is often claimed in the media that we are in an unprecedented and critical climatic situation and all the reported extreme weather events are said to be proving it.

In reality, there is no indication that most extreme weather events are more frequent or in any way more severe than in the past. Take hurricanes, for example. It’s true that the damage they cause has increased over time, but Shaviv says that’s because more people live near the coast. “If you look at the statistics of hurricanes making landfall in the US, which is a relatively reliable record, then you see that there is no significant change,” he says. Shaviv adds that, in reality, there is not even any reason to expect a warming climate to bring more hurricanes. “Sure, you need hotter waters to generate hurricanes, but you also need the gradient, you need the temperature difference between the equator and the subtropics in order to drive the hurricanes. And warmer Earth actually has a smaller temperature difference. So it’s not even clear ab initio whether you’re going to have more hurricanes or less,” Shaviv explains.

Large wildfires, for example, are also associated with climate warming, but Shaviv says there is no reason for this either. “In the US in the 1930s the annual amount of area which was burnt a year was way larger than what it is today,” he says, adding that the reality is that a large proportion of fires are caused by poor forest management, which fails to clear the forest floor of flammable material.

Towards nuclear energy

In the light of the above, climate change does not make it necessary to abandon fossil fuels. However, Shaviv says we should still move towards cleaner energy. Firstly, burning fossil fuels causes real environmental pollution – in particular coal, which is still on the rise worldwide. Secondly, fossil fuels will run out one day.

But mankind cannot replace these fuels with wind and solar power. “First of all, it’s very expensive. You can see that any country that has a lot of any of those, they pay much more for electricity,” Shaviv says. He suggests looking at electricity prices in countries such as Germany or Denmark, where wind and solar have been developed with billions of euros of government aid, and comparing them with, for example, France which uses nuclear power. What makes this form of energy so expensive is its intermittent nature – generation takes place when the sun shines and the wind blows. So to guarantee electricity supply, either huge storage capacity or backup systems, such as gas-fired power stations, are needed.

Shaviv believes that in the future, much more reliance should be placed on nuclear power, which does not have the pollution problems of fossil fuels and, unlike wind and solar, can provide a stable energy supply. However, the critics of this plan remind us of past nuclear accidents – Chernobyl in Ukraine, Three Mile Island in the USA and Fukushima in Japan. Each of these accidents had its own causes – in the case of Chernobyl and Three Mile Island, technical defects mixed with human error, and in the case of Fukushima, natural forces, in other words, the earthquake and tsunami. In the case of Fukushima in 2011, however, no one died as a direct result of the accident at the nuclear power plant (though thousands of people died as a result of the tsunami that devastated the coastline).

Shaviv says there is no point in comparing the safety of nuclear plants that have suffered accidents in the past with today’s technology. “I don’t think it’s going to be a problem in the sense that we can have an extremely safe design,” he says, adding that the wider deployment of nuclear power will happen whether the West joins in or not. “If you look at China, which is energy-hungry, they don’t care about public opinion as much as we do in the West. And they don’t have as much problem with regulation. So they’re just going to run forward and instead of building or opening a coal power plant every few weeks, in a few years, they’re going to be opening a nuclear power plant every few weeks,” Shaviv says. He adds that the West would also be wise to participate in this development, rather than moving in the opposite direction.

March 2025 Oceans Cooling Persists

Posted on April 23 by Ron Clutz

The best context for understanding decadal temperature changes comes from the world’s sea surface temperatures (SST), for several reasons:

The ocean covers 71% of the globe and drives average temperatures;
SSTs have a constant water content, (unlike air temperatures), so give a better reading of heat content variations;
A major El Nino was the dominant climate feature in recent years.

The Current Context

The chart below shows SST monthly anomalies as reported in HadSST4 starting in 2015 through February 2025. A global cooling pattern is seen clearly in the Tropics since its peak in 2016, joined by NH and SH cycling downward since 2016, followed by rising temperatures in 2023 and 2024.

Then in 2023-24 came an event resembling 2015-16 with a Tropical spike and two NH spikes alongside, all higher than 2015-16. There was also a coinciding rise in SH, and the Global anomaly was pulled up to 1.1°C last year, ~0.3° higher than the 2015 peak. Then NH started down autumn 2023, followed by Tropics and SH descending 2024 to the present. After 12 months of cooling in SH and the Tropics, the Global anomaly came back down, led by NH cooling the last 8 months from its 1.3C peak in August, down to 0.8C in March. With some recent warming in the Tropics and SH, all regions are now close together nearly at the global anomaly, about 0.1C higher than the average for this period.

Comment:

A longer view of SSTs

To enlarge image, open in new tab.

Contemporary AMO Observations

Then in 2024 the AMO anomaly started higher than any previous year, then leveled off for two months declining slightly into April. Remarkably, May showed an upward leap putting this on a higher track than 2023, and rising slightly higher in June. In July, August and September 2024 the anomaly declined, and despite a small rise in October, ended close to where it began. Now 2025 started much lower than the previous year and is headed sharply downward.

The pattern suggests the ocean may be demonstrating a stairstep pattern like that we have also seen in HadCRUT4.

Curiosity: Solar Coincidence?

Summary

Footnote: Why Rely on HadSST4

USS Pearl Harbor deploys Global Drifter Buoys in Pacific Ocean

Politicized Science Case Study: National Climate Assessment

Posted on April 8 by Ron Clutz

This post incorporates two dimensions of climate science reporting: firstly what and who are involved in the production, and secondly what the Trump administration might do to achieve a more balanced result. A recent article exposes the process by which the US National Climate Assessment (NCA) has been produced while ensuring that true believers control the content. Brent Scher writes at Daily Wire Meet The Government Consultants Raking In Millions To Spread Climate Doom. Excerpts in italics with my bolds and added images.

The government is outsourcing the ‘crown jewel’ of
climate change research to liberal climate consultants.

More than three decades ago, Congress launched an initiative called the U.S. Global Change Research Program. Today, it spends billions of dollars a year empowering liberal climate scientists to spread climate change doom.

The government group says its role is to provide the “scientific foundation to support informed decision-making across the United States” on climate change. It’s done so by producing five National Climate Assessment reports, which are considered the “crown jewel” of climate research.

Despite taking funding from at least ten separate government agencies, producing the report seems to be the group’s sole function. The most recent iteration — published in 2023 and still prominently showcased on its government website — warns that “severe climate risks to the United States will continue to grow.” The next report is due out in the next couple of years, according to E&E News.

The National Climate Assessment is not simply an intellectual exercise, but rather one that carries real policy might. Congress and agencies use it to justify regulations and funding decisions, and states and cities across the country lean on it as the non-partisan scientific foundation for their own climate action plans. In summary, it is the scientific bedrock for directing policy at all levels of government towards liberal climate change goals.

While the U.S. Global Change Research Program states on its website that it has a budget of $4.95 billion in 2025, it only lists two full-time employees. So, who’s getting paid to put the massive and consequential report together?

Sources familiar with past iterations of the National Climate Assessment say the work is largely outsourced to a group called ICF, a massive government contractor that has an active contract to work on the report. The Daily Wire identified at least one active contract from NASA for ICF to “support” the U.S. Global Change Research Program. ICF is set to be paid millions of dollars during the Trump administration to “assist the nation and the world to understand, assess, predict, and respond to human-induced and natural processes of global change.”

The contract was first announced in June 2021, and described as a $34 million, five-year contract to help with the National Climate Assessments. Only $18 million has been paid out, according to the government spending database. But with another assessment on deck and ICF under contract for another year, the additional $16 million could be disbursed in the next year.

A climate scientist who has worked on the National Climate Assessment
in the past says ICF runs the show, virtually controlling
the entire U.S. Global Change Research Program.

“By providing all staff for the USGCRP, a federal agency, the ICF exerts undue influence over the global change narrative and priorities presented by the federal government,” said the official, who requested anonymity to discuss the work. “The ICF, through the USGCRP, exerts an undue influence on the production of the National Climate Assessment every four years. With the exception of its Executive Director and the Director of the National Climate Assessment, the ICF supplies all staff associated with the USGCRP.”

ICF takes in far more in government contracts than its active $34 million from NASA. An analysis of federal spending data found that the consulting firm rakes in hundreds of millions of dollars each year through federal contracts, and took in over $2 billion during the Biden administration.

The consulting firm is likely aware that the scope of its government work could be slashed during Trump’s term, and so are investors. Its stock price was at $171 a share days ahead of last November’s election, but has since cratered to just $77 a share, the lowest it had been since the last time Trump was president. (Yes, the stock price fell before the current market volatility caused by tariffs).

Houston Keene, a former journalist who now leads a government transparency organization, argues that unnamed government consultants shouldn’t be paid millions to chart the nation’s climate policy.

“The public deserves an honest assessment from the government on the state of climate science,” Keene said. “That requires an objective, nonpartisan author who does not have financial interests in the outcome. ICF appears to be none of these things.”

“There can be no proper assessment with scientific integrity when a clearly partisan and financially conflicted activist organization is holding the pen,” he said.

A top Trump administration official, Russell Vought, has signaled that he wanted to exert more oversight over the next climate assessment. Vought runs the powerful Office of Management and Budget, and has openly stated that he wants to make deep cuts to “woke and weaponized” spending.

Vought has specifically called out the U.S. Global Change Research Program’s report, arguing that the bureaucrats who write it end up with outsized power over government action. He’s called for an investigation of the political leanings of the contractors that assemble the report.

A March 2025 report at SciAm provides background on recent developments regarding the NCA: Trump Official Who Tried to Downplay Major Climate Report Now Will Oversee It. Excerpts in italics with my bolds and added images.

Stuart Levenbach alarmed scientists years ago when he attempted
to meddle with a congressionally mandated climate report

Stuart Levenbach was tapped last month by administration officials to serve as associate director for natural resources, energy, science, and water in the Office of Management and Budget.

The previous time President Donald Trump was in the White House, Levenbach attempted to tone down the summary conclusions of the National Climate Assessment, a wide-ranging report that relies on the contributions of hundreds of researchers to assess how global warming is transforming the United States.

Scientists say Levenbach tried to downplay climate risks in the fourth installment of the report, which comes out every four years or so. In that edition, Levenbach was concerned especially with the higher greenhouse gas emissions assumptions the report partially relied on and sought to soften the language of the report’s summary, the scientists say.

“He was the one that tried to slow it down to the point of it not coming out,” said Don Wuebbles, a climate scientist at the University of Illinois who has worked on all five previous National Climate Assessments.

Levenbach’s delay tactics were ultimately unsuccessful, and the fourth installment of the report was released in 2018 on the day after Thanksgiving.

In response to questions from Politico’s E&E News, a Trump administration official with the Office of Management and Budget described the scientists’ concerns as “fake news.”

The National Climate Assessment is based on a range of emissions scenarios, including those that are not worst-case scenarios. The fourth version of the report concluded the country was not on track to cut carbon dioxide emissions at a pace to avoid some of the worst consequences of climate change.

At the time, Levenbach’s role at NOAA carried more weight than usual because the agency was operating without a permanent administrator, and did so for the entire first Trump presidency. Reached for comment, OMB spokeswoman Rachel Cauley did not deny that Levenbach tried to alter the report, but she criticized how it was put together.

“The assessment was riddled with the worst case scenario and
the authors weren’t transparent about it,” she said in a statement.”

Levenbach is joining OMB at a time when its director, Russ Vought, wants to suppress climate science throughout the federal government and increase Trump White House oversight over the next installment of the National Climate Assessment, which is due out in 2026 or 2027.

Levenbach’s appointment to a powerful White House role with oversight of the nation’s scientific endeavors comes at a time when the administration is preparing a possible challenge to the endangerment finding, a bedrock ruling which considers greenhouse gases a danger to public health and is a foundation of climate regulations.

March 2025 UAH Yo-yo Temps

Posted on April 5 by Ron Clutz

For reference I added an overlay of CO2 annual concentrations as measured at Mauna Loa. While temperatures fluctuated up and down ending flat, CO2 went up steadily by ~60 ppm, a 15% increase.

Furthermore, going back to previous warmings prior to the satellite record shows that the entire rise of 0.8C since 1947 is due to oceanic, not human activity.

gmt-warming-events

Chris Schoeneveld has produced a similar graph to the animation above, with a temperature series combining HadCRUT4 and UAH6. H/T WUWT

March 2025 UAH Temps Yo-yo, Ocean First, Then Land

UAH has updated their TLT (temperatures in lower troposphere) dataset for March 2025. Due to one satellite drifting more than can be corrected, the dataset has been recalibrated and retitled as version 6.1 Graphs here contain this updated 6.1 data. Posts on their reading of ocean air temps this month are ahead of the update from HadSST4. I posted recently on SSTs February 2025 Oceans Keep Cool. These posts have a separate graph of land air temps because the comparisons and contrasts are interesting as we contemplate possible cooling in coming months and years.

After a change in priorities, updates are now exclusive to HadSST4. For comparison we can also look at lower troposphere temperatures (TLT) from UAHv6.1 which are now posted for March 2025. The temperature record is derived from microwave sounding units (MSU) on board satellites like the one pictured above. Recently there was a change in UAH processing of satellite drift corrections, including dropping one platform which can no longer be corrected. The graphs below are taken from the revised and current dataset.

Land Air Temperatures Tracking in Seesaw Pattern

Here we have fresh evidence of the greater volatility of the Land temperatures, along with extraordinary departures by SH land. The seesaw pattern in Land temps is similar to ocean temps 2021-22, except that SH is the outlier, hitting bottom in January 2023. Then exceptionally SH goes from -0.6C up to 1.4C in September 2023 and 1.8C in August 2024, with a large drop in between. In November, SH and the Tropics pulled the Global Land anomaly further down despite a bump in NH land temps. February showed a sharp drop in NH land air temps from 1.07C down to 0.56C, pulling the Global land anomaly downward from 0.9C to 0.6C. Now that drop is reversed in March with both NH and Global land back to January values, despite another drop in SH land air temps.

The Bigger Picture UAH Global Since 1980

With the sharp drops in Nov., Dec. and January 2023 temps, there was no increase over 1980. Then in 2023 the buildup to the October/November peak exceeded the sharp April peak of the El Nino 1998 event. It also surpassed the February peak in 2016. In 2024 March and April took the Global anomaly to a new peak of 0.94C. The cool down started with May dropping to 0.9C, and in June a further decline to 0.8C. October went down to 0.7C, November and December dropped to 0.6C. February went down to 0.5C, now back up to 0.6C driven by the bounce in NH land air temps.

The graph reminds of another chart showing the abrupt ejection of humid air from Hunga Tonga eruption.

The Right Climate Stuff

Posted on April 3 by Ron Clutz

Not everyone is aware that the scientists and engineers who made the NASA space program successful disputed the global warming/climate change narrative promoted at the agency by people like James Hansen.

After all the slogan in the NASA workplace was that of Edward Deming, and they were only convinced by the facts rather than feelings or opinions about the future. Many of them formed the Right Climate Stuff Foundation.

https://www.therightclimatestuff.com/

In particular Walter Cunningham explained his reasoning in an article In Science, Ignorance is not Bliss. Excerpts in italics with my bolds and added images.

NASA has played a key role in one of the greatest periods of scientific progress in history. It is uniquely positioned to collect the most comprehensive data on our biosphere. For example, recently generated NASA data enabled scientists to finally understand the Gulf Stream warming mechanism and its effect on European weather. Such data will allow us to improve our models, resulting in better seasonal forecasts.

NASA’s Aqua satellite is showing that water vapor, the dominant greenhouse gas, works to offset the effect of carbon dioxide (CO2). This information, contrary to the assumption used in all the warming models, is ignored by global warming alarmists.

Climate understanding and critical decision making require
comprehensive data about our planet’s land, sea, and atmosphere.

Without an adequate satellite system to provide such data, policy efforts and monitoring international environmental agreements are doomed to failure. Our satellite monitoring capability is being crippled by interagency wrangling and federal budget issues. As much as a third of our satellites need replacing in the next couple of years.

NASA should be at the forefront in the collection of scientific evidence and debunking the current hysteria over human-caused, or Anthropogenic Global Warming (AGW). Unfortunately, it is becoming just another agency caught up in the politics of global warming, or worse, politicized science.

Advocacy is replacing objective evaluation of data, while
scientific data is being ignored in favor of emotions and politics.

There are excellent correlations between the regular fluctuations of the Sun and the Earth’s temperature, while scientists can not find a relationship between industrial activity, energy consumption, and global temperatures. But global warming is an issue no longer being decided in the scientific arena.

Saying the Earth is warming is to state the obvious. Since the end of the ice age, the Earth’s temperature has increased approximately 16 degrees Fahrenheit and sea levels have risen a total of 300 feet. That is certain and measurable evidence of warming, but it is not evidence of AGW—human-caused warming.

We can track the temperature of the Earth back for millennia. Knowing the temperature of the Earth, past or present, is a matter of collecting data, analyzing it, and coming up with the best answer to account for the data. Collecting such data on a global basis is a NASA forte. I believe in global climate change, but there is no way that humans can influence the temperature of our planet to any measurable degree with the tools currently at their disposal. Any human contribution to global temperature change is lost in the noise of terrestrial and cosmic factors.

Our beautiful home planet has been warming and cooling for the last 4.8 billion years. Most recently, it has been warming—be it ever so slightly—but there is nothing unusual about it! The changes and rates of change in the Earth’s temperature, just since the Industrial Revolution, have occurred many times in our climatic history. While climate scientists generally agree that the Earth’s temperature is always changing, not many of them would say that humans are responsible for those changes.

None of this is to say there are not legitimate reasons to restrict emissions of any number of chemicals into the atmosphere. We should just not fool ourselves into thinking we will change the temperature of the Earth by doing so.

In a December 2007 Senate report, 400 prominent scientists signed a letter pointing out that climate change was a well-known natural phenomenon, and that adapting to it is far more sensible than attempting to prevent it. Their ranks included experts in climatology, geology, oceanography, biology, glaciology, biogeography, meteorology, economics, chemistry, mathematics, environmental sciences, engineering, physics, and paleo-climatology.

Their message: When changes are gradual, man has
an almost infinite ability to adapt and evolve.

The fearmongers of global warming base their case on the correlation between CO2 and global temperature, even though we cannot be sure which is cause and which is effect. Historically, temperature increases have preceded high CO2 levels, and there have been periods when atmospheric CO2 levels were as much as 16 times what they are now, periods characterized not by warming but by glaciation. You might have to go back half a million years to match our current level of atmospheric CO2, but you only have to go back to the Medieval Warming Period, from the 10th to the 14th Century, to find an intense global warming episode, followed immediately by the drastic cooling of the Little Ice Age. Neither of these events were caused by variations in CO2 levels.

Even though CO2 is a relatively minor constituent of “greenhouse gases,” alarmists have made it the whipping boy for global warming (probably because they know how fruitless it would be to propose controlling other principal constituents, H2O, CH4, and N2O). Since human activity does contribute a tiny portion of atmospheric CO2, they blame us for global warming.

Other inconvenient facts ignored by the activists: Carbon dioxide is a nonpolluting gas, essential for plant photosynthesis. Higher concentrations of CO2 in the atmosphere produce bigger harvests.

In spite of warnings of severe consequences from rising seas, droughts, severe weather, species extinction, and other disasters, the U.S. has not been stampeded into going along with the recommendations of the UN Panel on Climate Change (IPCC)—so far. Even though evidence supports the American position, we have begun to show signs of caving in to the alarmists.

With scientific evidence going out of style,
emotional arguments and anecdotal data are ruling the day.

The media subjects us to one frightening image of environmental nightmare after another, linking each to global warming. Journalists and activist scientists use hurricanes, wildfires, and starving polar bears to appeal to our emotions, not to our reason. They are far more concerned with anecdotal observations, such as the frozen sea ice inside the Arctic Circle, than they are with understanding why it is happening and how frequently it has occurred in the past.

After warnings that 2007 would be the hottest year on record and a record year for hurricanes, what we experienced was the coolest year since 2001 and, by some measures, the most benign hurricane season in the Northern Hemisphere in three decades.

Even though recent changes in our atmosphere are all within the bounds of the Earth’s natural variability, a growing number of people are willing to throw away trillions of dollars on fruitless solutions. Why do we allow emotional appeals and anecdotal data to shape our conclusions and influence our expenditures with the science and technology we have available at our fingertips?

The situation is complex, but the sad state of scientific literacy in America today is partially to blame for belief in AGW. When a 2006 National Science Foundation survey found 25 percent of Americans not knowing the Earth revolves around the Sun, you know that science education is at a new low and society is vulnerable to the emotional appeal of AGW.

And don’t underestimate the role of politics and political correctness.

The public debate should focus on the real cause of global temperature change and whether we can do anything about it. Is global warming a natural inevitability, or is it AGW—human caused?

The conflict over AGW has deteriorated into a religious war; a war between true believers in human-caused global warming and nonbelievers; between those who accept AGW on faith and those who consider themselves more sensible and better informed. “True believers” are beyond being interested in evidence; it is impossible to reason a person out of positions they have not been reasoned into.

It doesn’t help that NASA scientist James Hansen was one of the early alarmists claiming humans caused global warming. Hansen is a political activist who spreads fear even when NASA’s own data contradict him.

Warming in the upper atmosphere should occur before any surface warming effect, but NASA’s own data show that has not been happening. Global temperature readings—accurate to 0.1 degree Celsius—are gathered by orbiting satellites. Interestingly, in the 18 years those satellites have been recording global temperatures, they have actually shown a slight decrease in average temperatures.

Hansen is currently calling for a reduction of atmospheric CO2 by 10 percent and a moratorium on coal-fired power plants, while claiming the Bush administration is censoring him. Other so-called scientists are saying the world must bring carbon emissions to near zero to keep temperatures from rising.

In today’s politically correct environment, many are reluctant to dispute the popular wisdom; when they do, they are frequently ignored. When NASA Administrator Michael Griffin, Hansen’s boss and a distinguished scientist in his own right, attempted to draw a distinction between Hansen’s personal and political views and the science conducted by his agency, he was soon forced to back off.

It is the true believers who, when they have no facts on their side, try to silence their critics. When former NASA mathematician Ferenc Miskolczi pointed out that “greenhouse warming” may be mathematically impossible, NASA would not allow him to publish his work. Miskolczi dared to question the simplifying assumption in the warming model that the atmosphere is infinitely thick. He pointed out that when you use the correct thickness—about 65 miles—the greenhouse effect disappears! Ergo: no AGW. Miskolczi resigned in disgust and published his proof in the peer reviewed Hungarian journal Weather. [See: The Curious Case of Dr. Miskolczi]

For nearly a decade now, there has been no global warming. Even though atmospheric CO2 has continued to accumulate—up about 4 percent in the last 10 years—the global mean temperature has remained flat. That should raise obvious questions about CO2 being the cause of climate change.

Instead, AGW enthusiasts are embracing more regulation, greater government spending, and higher taxes in a futile attempt to control what is beyond our control—the Earth’s temperature. One of their political objectives, unstated of course, is the transfer of wealth from rich nations to poor nations or, as the social engineers put it, from the North to the South, which may be their real agenda.

Climate Lemmings

In the face of overwhelming evidence for natural temperature variation, proponents of AGW are resorting to a precautionary argument: “We must do something just in case we are responsible, because the consequences are too terrible if we are to blame and do nothing.” They hope to stampede government entities into committing huge amounts of money before their fraud is completely exposed—before science and truth save the day.

Politicians think they can reverse global warming by stabilizing CO2 emissions with a cockamamie scheme of “cap and trade.” A government entity would sell CO2 allocations to those industries producing it. The trillions of dollars in new taxes and devastation to the economy would be justified by claiming it will lower the temperature of the Earth. This rationalization is dependent on two assumptions: (1) that CO2 is responsible for the cause of changes in the Earth’s temperature, and (2) a warmer Earth would be bad for humanity.

The reality is that atmospheric CO2 has a minimal impact on greenhouse gases and world temperature. Water vapor is responsible for 95 percent of the greenhouse effect. CO2 contributes just 3.6 percent, with human activity responsible for only 3.2 percent of that. That is why some studies claim CO2 levels are largely irrelevant to global warming.

Without the greenhouse effect to keep our world warm, the planet would have an average temperature of minus 18 degrees Celsius. Because we do have it, the temperature is a comfortable plus 15 degrees Celsius. Based on the seasonal and geographic distribution of any projected warming, a good case can be made that a warmer average temperature would be even more beneficial for humans.

For a tiny fraction of the trillions of dollars a cap-and-trade system would eventually cost the United States, we could pay for development of clean coal, oil-shale recovery systems, and nuclear power, and have enough left over to pay for exploration of our solar system.

By law, NASA cannot involve itself in politics, but it can surely champion the role of science to inform politicians. With so many uninformed and misguided politicians ignoring the available science, NASA should fill the void. NASA is synonymous with science. Allowing our priorities to drift away from hard science is tantamount to embracing decadence. NASA will surely suffer; and politicizing science is killing it.

I do see hopeful signs that some true believers are beginning to harbor doubts about AGW. Let’s hope that NASA can focus the global warming discussion back on scientific evidence before we perpetrate an economic disaster on ourselves.

Walter Cunningham, (1932–2023) geophysicist, fighter pilot and Apollo 7 astronaut, who flew the first test flight of the Apollo Program, Apollo 7. In 2010, Cunningham published a short book titled “Global Warming: Facts versus Faith” His editorial was published in the Houston Chronicle on August 15, 2010, Climate change alarmists ignore scientific methods. (When You Don’t Have the Facts, Appeal to Public Opinion). In 2012, he and other former astronauts and NASA employees sent a letter to the agency criticizing its role advocating a high degree of certainty that man-made CO2 is a major cause of climate change while neglecting empirical evidence that calls the theory into question.

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