Climate Science

2019 Evidence of Nature’s Sunscreen

Posted on by Ron Clutz

Greenhouse with adjustable sun screens to control warming.

2019 Update  Hard Evidence of Solar Impact upon Earth Cloudiness

Later on is a reprinted discussion of global dimming and brightness resulting from fluctuating cloud cover.  This is topical because of new empirical research findings coming out of Asia.  H/T GWPF.  A study published by Kobe University research center is Revealing the impact of cosmic rays on the Earth’s climate.  Excerpts in italics with my bolds.

New evidence suggests that high-energy particles from space known as galactic cosmic rays affect the Earth’s climate by increasing cloud cover, causing an “umbrella effect”.

When galactic cosmic rays increased during the Earth’s last geomagnetic reversal transition 780,000 years ago, the umbrella effect of low-cloud cover led to high atmospheric pressure in Siberia, causing the East Asian winter monsoon to become stronger. This is evidence that galactic cosmic rays influence changes in the Earth’s climate. The findings were made by a research team led by Professor Masayuki Hyodo (Research Center for Inland Seas, Kobe University) and published on June 28 in the online edition of Scientific Reports.

The Svensmark Effect is a hypothesis that galactic cosmic rays induce low cloud formation and influence the Earth’s climate. Tests based on recent meteorological observation data only show minute changes in the amounts of galactic cosmic rays and cloud cover, making it hard to prove this theory. However, during the last geomagnetic reversal transition, when the amount of galactic cosmic rays increased dramatically, there was also a large increase in cloud cover, so it should be possible to detect the impact of cosmic rays on climate at a higher sensitivity.

(The Svenmark Effect is explained in essay The cosmoclimatology theory)

How Nature’s Sunscreen Works (from Previous Post)

A recent post Planetary Warming: Back to Basics discussed a recent paper by Nikolov and Zeller on the atmospheric thermal effect measured on various planets in our solar system. They mentioned that an important source of temperature variation around the earth’s energy balance state can be traced to global brightening and dimming.

This post explores the fact of fluctuations in the amount of solar energy reflected rather than absorbed by the atmosphere and surface. Brightening refers to more incoming solar energy from clear and clean skies. Dimming refers to less solar energy due to more sunlight reflected in the atmosphere by the presence of clouds and aerosols (air-born particles like dust and smoke).

The energy budget above from ERBE shows how important is this issue. 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.

The leading research on global brightening/dimming is done at the Institute for Atmospheric and Climate Science of ETH Zurich, led by Martin Wild, senior scientist specializing in the subject.

Special instruments have been recording the solar radiation that reaches the Earth’s surface since 1923. However, it wasn’t until the International Geophysical Year in 1957/58 that a global measurement network began to take shape. The data thus obtained reveal that the energy provided by the sun at the Earth’s surface has undergone considerable variations over the past decades, with associated impacts on climate.

The initial studies were published in the late 1980s and early 1990s for specific regions of the Earth. In 1998 the first global study was conducted for larger areas, like the continents Africa, Asia, North America and Europe for instance.

Now ETH has announced The Global Energy Balance Archive (GEBA) version 2017: A database for worldwide measured surface energy fluxes. The title is a link to that paper published in May 2017 explaining the facility and some principal findings. The Archive itself is at  http://www.geba.ethz.ch.

For example, Figure 2 below provides the longest continuous record available in GEBA: surface downward shortwave radiation measured in Stockholm since 1922. Five year moving average in blue, 4th order regression model in red. Units Wm-2. Substantial multidecadal variations become evident, with an increase up to the 1950s (“early brightening”), an overall decline from the 1950s to the 1980s (“dimming”), and a recovery thereafter (“brightening”).
Figure 5. Composite of 56 European GEBA time series of annual surface downward shortwave radiation (thin line) from 1939 to 2013, plotted together with a 21 year Gaussian low-pass filter ((thick line). The series are expressed as anomalies (in Wm-2) from the 1971–2000 mean. Dashed lines are used prior to 1961 due to the lower number of records for this initial period. Updated from Sanchez-Lorenzo et al. (2015) including data until December 2013.
Martin Wild explains in a 2016 article Decadal changes in radiative fluxes at land and ocean surfaces and their relevance for global warming. From the Conclusion (SSR refers to solar radiation incident upon the surface)

However, observations indicate not only changes in the downward thermal fluxes, but even more so in their solar counterparts, whose records have a much wider spatial and temporal coverage. These records suggest multidecadal variations in SSR at widespread land-based observation sites. Specifically, declining tendencies in SSR between the 1950s and 1980s have been found at most of the measurement sites (‘dimming’), with a partial recovery at many of the sites thereafter (‘brightening’).

With the additional information from more widely measured meteorological quantities which can serve as proxies for SSR (primarily sunshine duration and DTR), more evidence for a widespread extent of these variations has been provided, as well as additional indications for an overall increasing tendency in SSR in the first part of the 20th century (‘early brightening’).

It is well established that these SSR variations are not caused by variations in the output of the sun itself, but rather by variations in the transparency of the atmosphere for solar radiation. It is still debated, however, to what extent the two major modulators of the atmospheric transparency, i.e., aerosol and clouds, contribute to the SSR variations.

The balance of evidence suggests that on longer (multidecadal) timescales aerosol changes dominate, whereas on shorter (decadal to subdecadal) timescales cloud effects dominate. More evidence is further provided for an increasing influence of aerosols during the course of the 20th century. However, aerosol and clouds may also interact, and these interactions were hypothesized to have the potential to amplify and dampen SSR trends in pristine and polluted areas, respectively.

No direct observational records are available over ocean surfaces. Nevertheless, based on the presented conceptual ideas of SSR trends amplified by aerosol–cloud interactions over the pristine oceans, modeling approaches as well as the available satellite-derived records it appears plausible that also over oceans significant decadal changes in SSR occur.

The coinciding multidecadal variations in SSTs and global aerosol emissions may be seen as a smoking gun, yet it is currently an open debate to what extent these SST variations are forced by aerosol-induced changes in SSR, effectively amplified by aerosol– cloud interactions, or are merely a result of unforced natural variations in the coupled ocean atmosphere system. Resolving this question could state a major step toward a better understanding of multidecadal climate change.

Another paper co-authored by Wild discusses the effects of aerosols and clouds The solar dimming/brightening effect over the Mediterranean Basin in the period 1979 − 2012. (NSWR is Net Short Wave Radiation, that is equal to surface solar radiation less reflected)

The analysis reveals an overall increasing trend in NSWR (all skies) corresponding to a slight solar brightening over the region (+0.36 Wm−2per decade), which is not statistically significant at 95% confidence level (C.L.). An increasing trend(+0.52 Wm−2per decade) is also shown for NSWR under clean skies (without aerosols), which is statistically significant (P=0.04).

This indicates that NSWR increases at a higher rate over the Mediterranean due to cloud variations only, because of a declining trend in COD (Cloud Optical Depth). The peaks in NSWR (all skies) in certain years (e.g., 2000) are attributed to a significant decrease in COD (see Figs. 9 and 10), whilethe two data series (NSWRall and NSWRclean) are highly correlated(r=0.95).

This indicates that cloud variation is the major regulatory factor for the amount and multi-decadal trends in NSWR over the Mediterranean Basin. (Note: Lower cloud optical depth is caused by less opaque clouds and/or decrease in overall cloudiness)

On the other hand, the results do not reveal a reversal from dimming to brightening during 1980s, as shown in several studies over Europe (Norris and Wild, 2007;Sanchez-Lorenzoet al., 2015), but a rather steady slight increasing trend in solar radiation, which, however, seems to be stabilized during the last years of the data series, in agreement with Sanchez-Lorenzo et al. (2015). Similarly, Wild (2012) reported that the solar brightening was less distinct at European sites after 2000 compared to the 1990s.

In contrast, the NSWR under clear (cloudless) skies shows a slight but statistically significant decreasing trend (−0.17 Wm−2per decade,P=0.002), indicating an overall decrease in NSWR over the Mediterranean due to water-vapor variability suggesting a transition to more humid environment under a warming climate.

Other researchers find cloudiness more dominant than aerosols. For example, The cause of solar dimming and brightening at the Earth’s surface during the last half century: Evidence from measurements of sunshine duration by Gerald Stanhill et al.

Analysis of the Angstrom-Prescott relationship between normalized values of global radiation and sunshine duration measured during the last 50 years made at five sites with a wide range of climate and aerosol emissions showed few significant differences in atmospheric transmissivity under clear or cloud-covered skies between years when global dimming occurred and years when global brightening was measured, nor in most cases were there any significant changes in the parameters or in their relationships to annual rates of fossil fuel combustion in the surrounding 1° cells. It is concluded that at the sites studied changes in cloud cover rather than anthropogenic aerosols emissions played the major role in determining solar dimming and brightening during the last half century and that there are reasons to suppose that these findings may have wider relevance.

Summary

The final words go to Martin Wild from Enlightening Global Dimming and Brightening.

Observed Tendencies in surface solar radiation
Figure 2.  Changes in surface solar radiation observed in regions with good station coverage during three periods.(left column) The 1950s–1980s show predominant declines (“dimming”), (middle column) the 1980s–2000 indicate partial recoveries (“brightening”) at many locations, except India, and (right column) recent developments after 2000 show mixed tendencies. Numbers denote typical literature estimates for the specified region and period in W m–2 per decade.  Based on various sources as referenced in Wild (2009).

The latest updates on solar radiation changes observed since the new millennium show no globally coherent trends anymore (see above and Fig. 2). While brightening persists to some extent in Europe and the United States, there are indications for a renewed dimming in China associated with the tremendous emission increases there after 2000, as well as unabated dimming in India (Streets et al. 2009; Wild et al. 2009).

We cannot exclude the possibility that we are currently again in a transition phase and may return to a renewed overall dimming for some years to come.

One can’t help but see the similarity between dimming/brightening and patterns of Global Mean Temperature, such as HadCrut.

Footnote: For more on clouds, precipitation and the ocean, see Here Comes the Rain Again

June Mixes up Both Land and Sea Temps

Posted on by Ron Clutz

banner-blog

With apologies to Paul Revere, this post is on the lookout for cooler weather with an eye on both the Land and the Sea.  UAH has updated their tlt (temperatures in lower troposphere) dataset for June.   Previously I have done posts on their reading of ocean air temps as a prelude to updated records from HADSST3. This month also has a separate graph of land air temps because the comparisons and contrasts are interesting as we contemplate possible cooling in coming months and years.

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.  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 technical enhancement to HadSST3 delayed March and April updates, May was posted early in June, hopefully a signal the future months will also appear more promptly.  For comparison we can look at lower troposphere temperatures (TLT) from UAHv6 which are now posted for June. 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 new 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 temps since January 2015.

June ocean air temps rose in all regions after May’s drop, resulting in the Global average back up matching June 2017.  NH warming in June was slight while warming in SH and the Tropics was stronger.  The temps this June are warmer than 2018, similar to 06/2017, and of course lower than 2016.

Land Air Temperatures Tracking Downward 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 record air temps at 2 meters above ground.  UAH gives tlt anomalies for air over land separately from ocean air temps.  The graph updated for June is below.

The greater volatility of the Land temperatures was evident earlier, calmed down recently, and now diverging again.  SH declined slightly, NH recovered a bit from recent drops, and the Tropics land jumped up.  The result is an upward bump, since NH dominates, having twice as much land area as SH.  Note how global peaks mirror NH peaks.  The present situation is close to 06/2017 except for SH being somewhat warmer now.

The longer term picture from UAH is a return to the mean for the period starting with 1995:

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, now more than 1C lower than the peak in 2016.  TLT measures started the recent cooling later than SSTs from HadSST3, but are now showing the same pattern.  It seems obvious that despite the three El Ninos, their warming has not persisted, and without them it would probably have cooled since 1995.  Of course, the future has not yet been written.

The LIA Warming Rebound Is Over

Posted on by Ron Clutz

Figure 1. Graph showing the number of volcanoes reported to have been active each year since 1800 CE. Total number of volcanoes with reported eruptions per year (thin upper black line) and 10-year running mean of same data (thick upper red line). Lower lines show only the annual number of volcanoes producing large eruptions (>= 0.1 km3 of tephra or magma) and scale is enlarged on the right axis; thick red lower line again shows 10-year running mean. Global Volcanism Project Discussion

Thanks to Dr. Francis Manns for drawing my attention to the role of Volcanoes as a climate factor, particularly related to the onset of the Little Ice Age (LIA), 1400 to 1900 AD. I was aware that the temperature record since about 1850 can be explained by a steady rise of 0.5C per century rebound overlaid with a quasi-60 year cycle, most likely oceanic driven. See below Dr. Syun Akasofu 2009 diagram from his paper Two Natural Components of Recent Warming.
When I presented this diagram to my warmist friends, they would respond, “But you don’t know what caused the LIA or what ended it!” To which I would say, “True, but we know it wasn’t due to burning fossil fuels.” Now I find there is a body of evidence suggesting what caused the LIA and why the temperature rebound may be over. Part of it is a familiar observation that the LIA coincided with a period when the sun was lacking sunspots, the Maunder Minimum.

Not to be overlooked is the climatic role of volcano activity inducing deep cooling patterns such as the LIA.  Jihong Cole-Dai explains in a paper published 2010 entitled Volcanoes and climate. Excerpt in italics with my bolds.

There has been strong interest in the role of volcanism during the climatic episodes of Medieval Warm Period (MWP,800–1200 AD) and Little Ice Age (LIA, 1400–1900AD), when direct human influence on the climate was negligible. Several studies attempted to determine the influence of solar forcing and volcanic forcing and came to different conclusions: Crowley and colleagues suggested that increased frequency of stratospheric eruptions in the seventeenth century and again in the early nineteenth century was responsible in large part for LIA. Shindell et al. concluded that LIA is the result of reduced solar irradiance, as seen in the Maunder Minimum of sunspots, during the time period. Ice core records show that the number of large volcanic eruptions between 800 and 1100 AD is possibly small (Figure 1), when compared with the eruption frequency during LIA. Several researchers have proposed that more frequent large eruptions during the thirteenth century(Figure 1) contributed to the climatic transition from MWP to LIA, perhaps as a part of the global shift from a warmer to a colder climate regime. This suggests that the volcanic impact may be particularly significant during periods of climatic transitions.

How volcanoes impact on the atmosphere and climate

Alan Robock explains Climatic Impacts of Volcanic Eruptions in Chapter 53 of the Encyclopedia of Volcanoes.  Excerpts in italics with my bolds.

The major component of volcanic eruptions is the matter that emerges as solid, lithic material or solidifies into large particles, which are referred to as ash or tephra. These particles fall out of the atmosphere very rapidly, on timescales of minutes to a few days, and thus have no climatic impacts but are of great interest to volcanologists, as seen in the rest of this encyclopedia. When an eruption column still laden with these hot particles descends down the slopes of a volcano, this pyroclastic flow can be deadly to those unlucky enough to be at the base of the volcano. The destruction of Pompeii and Herculaneum after the AD 79 Vesuvius eruption is the most famous example.

Volcanic eruptions typically also emit gases, with H2O, N2, and CO2 being the most abundant. Over the lifetime of the Earth, these gases have been the main source of the Earth’s atmosphere and ocean after the primitive atmosphere of hydrogen and helium was lost to space. The water has condensed into the oceans, the CO2 has been changed by plants into O2 or formed carbonates, which sink to the ocean bottom, and some of the C has turned into fossil fuels. Of course, we eat plants and animals, which eat the plants, we drink the water, and we breathe the oxygen, so each of us is made of volcanic emissions. The atmosphere is now mainly composed of N2 (78%) and O2 (21%), both of which had sources in volcanic emissions.

Of these abundant gases, both H2O and CO2 are important greenhouse gases, but their atmospheric concentrations are so large (even for CO2 at only 400 ppm in 2013) that individual eruptions have a negligible effect on their concentrations and do not directly impact the greenhouse effect. Global annually averaged emissions of CO2 from volcanic eruptions since 1750 have been at least 100 times smaller than those from human activities. Rather the most important climatic effect of explosive volcanic eruptions is through their emission of sulfur species to the stratosphere, mainly in the form of SO2, but possibly sometimes as H2S. These sulfur species react with H2O to form H2SO4 on a timescale of weeks, and the resulting sulfate aerosols produce the dominant radiative effect from volcanic eruptions.

The major effect of a volcanic eruption on the climate system is the effect of the stratospheric cloud on solar radiation (Figure 53.1). Some of the radiation is scattered back to space, increasing the planetary albedo and cooling the Earth’s atmosphere system. The sulfate aerosol particles (typical effective radius of 0.5 mm, about the same size as the wavelength of visible light) also forward scatter much of the solar radiation, reducing the direct solar beam but increasing the brightness of the sky. After the 1991 Pinatubo eruption, the sky around the sun appeared more white than blue because of this. After the El Chicho´n eruption of 1982 and the Pinatubo eruption of 1991, the direct radiation was significantly reduced, but the diffuse radiation was enhanced by almost as much. Nevertheless, the volcanic aerosol clouds reduced the total radiation received at the surface.

Crowley et al 2008 go into the details in their paper Volcanism and the Little Ice Age. Excerpts in italics with my bolds.

Although solar variability has often been considered the primary agent for LIA cooling, the most comprehensive test of this explanation (Hegerl et al., 2003) points instead to volcanism being substantially more important, explaining as much as 40% of the decadal-scale variance during the LIA. Yet, one problem that has continually plagued climate researchers is that the paleo-volcanic record, reconstructed from Antarctic and Greenland ice cores, cannot be well calibrated against the instrumental record. This is because the primary instrumental volcano reconstruction used by the climate community is that of Sato et al. (1993), which is relatively poorly constrained by observations prior to 1960 (especially in the southern hemisphere).

Here, we report on a new study that has successfully calibrated the Antarctic sulfate record of volcanism from the 1991 eruptions of Pinatubo (Philippines) and Hudson (Chile) against satellite aerosol optical depth (AOD) data (AOD is a measure of stratospheric transparency to incoming solar radiation). A total of 22 cores yield an area-weighted sulfate accumulation rate of 10.5 kg/km2 , which translates into a conversion rate for AOD of 0.011 AOD/ kg/km2 sulfate. We validated our time series by comparing a canonical growth and decay curve for eruptions for Krakatau (1883), the 1902 Caribbean eruptions (primarily Santa Maria), and the 1912 eruption of Novarupta/Katmai (Alaska)

We therefore applied the methodology to part of the LIA record that had some of the largest temperature changes over the last millennium.

Figure 2: Comparison of 30-90°N version of ice core reconstruction with Jones et al. (1998) temperature reconstruction over the interval 1630-1850. Vertical dashed lines denote levels of coincidence between eruptions and reconstructed cooling. AOD = Aerosol Optical Depth.

The ice core chronology of volcanoes is completely independent of the (primarily) tree ring based temperature reconstruction. The volcano reconstruction is deemed accurate to within 0 ± 1 years over this interval. There is a striking agreement between 16 eruptions and cooling events over the interval 1630-1850. Of particular note is the very large cooling in 1641-1642, due to the concatenation of sulfate plumes from two eruptions (one in Japan and one in the Philippines), and a string of eruptions starting in 1667 and culminating in a large tropical eruption in 1694 (tentatively attributed to Long Island, off New Guinea). This large tropical eruption (inferred from ice core sulfate peaks in both hemispheres) occurred almost exactly at the beginning of the coldest phase of the LIA in Europe and represents a strong argument against the implicit link of Late Maunder Minimum (1640-1710) cooling to solar irradiance changes.

Figure 1: Comparison of new ice core reconstruction with various instrumental-based reconstructions of stratospheric aerosol forcing. The asterisks refer to some modification to the instrumental data; for Sato et al. (1993) and the Lunar AOD, the asterisk refers to the background AOD being removed for the last 40 years. For Stothers (1996), it refers to the fact that instrumental observations for Krakatau (1883) and the 1902 Caribbean eruptions were only for the northern hemisphere. To obtain a global AOD for these estimates we used Stothers (1996) data for the northern hemisphere and our data for the southern hemisphere. The reconstruction for Agung eruption (1963) employed Stothers (1996) results from 90°N-30°S and the Antarctic ice core data for 30-90°S.

During the 18th century lull in eruptions, temperatures recovered somewhat but then cooled early in the 19th century. The sequence begins with a newly postulated unknown tropical eruption in midlate 1804, which deposited sulfate in both Greenland and Antarctica. Then, there are four well-documented eruptions—an unknown tropical eruption in 1809, Tambora (1815) and a second doublet tentatively attributed in part to Babuyan (Philippines) in 1831 and Cosiguina (Nicaragua) in 1835. These closely spaced eruptions are not only large but have a temporally extended effect on climate, due to the fact that they reoccur within the 10-year recovery timescale of the ocean mixed layer.

The ocean has not recovered from the first eruption so the second eruption drives the temperatures to an even lower state.

Implications for Contemporary Climate Science

In this context Dr. Francis Manns went looking for a volcanic signature in recent temperature records. His paper is Volcano and Enso Punctuation of North American Temperature: Regression Toward the Mean  Excerpts in italics with my bolds.

Abstract: Contrary to popular media and urban mythology the global warming we have experienced since the Little Ice Age is likely finished. A review of 10 temperature time series from US cities ranging from the hottest in Death Valley, CA, to possible the most isolated and remote at Key West, FL, show rebound from the Little Ice Age (which ended in the Alps by 1840) by 1870. The United States reached temperatures like modern temperatures (1950 – 2000) by about 1870, then declined precipitously principally caused by Krakatoa, and a series of other violent eruptions. Nine of these time series started when instrumental measurement was in its infancy and the world was cooled by volcanic dust and sulphate spewed into the atmosphere and distributed by the jet streams. These ten cities represent a sample of the millions of temperature measurements used in climate models. The average annual temperatures are useful because they account for seasonal fluctuations. In addition, time series from these cities are punctuated by El Nino Southern Oscillation (ENSO).

As should be expected, temperature at each city reacted differently to differing events. Several cities measured the effects of Krakatoa in 1883 while only Death Valley, CA and Berkeley CA sensed the minor new volcano Paricutin in Michoacán, Mexico. The Key West time series shows rapid rebound from the Little Ice Age as do Albany, NY, Harrisburg, PA, and Chicago. IL long before the petroleum-industrial revolution got into full swing. Recording at most sites started during a volcanic induced temperature minimum thus giving an impression of global warming to which industrial carbon dioxide is persuasively held responsible. Carbon dioxide, however, cannot be proven responsible for these temperatures. These and likely subsequent temperatures could be the result of regression to the normal equilibrium temperatures of the earth (for now). If one were to remove the volcanic punctuation and El Nino Southern Oscillation (ENSO) input many would display very little alarming warming from 1815 to 2000. This review illustrates the weakness of linear regression as a measure of change. If there is a systemic reason for the global warming hypothesis, it is an anthropogenic error in both origin and termination. ENSO compliments and confirms the validity of NOAA temperature data. Temperatures since 2000 during the current hiatus are not available because NOAA has closed the public website.

Example of time series from Manns. Numbers refer to major named volcano eruptions listed in his paper.  For instance, #3 was Krakatoa

The cooling effect is said to have lasted for 5 years after Krakatoa erupted – from 1883 to 1888. Examination of these charts, However, shows that, e.g., Krakatoa did not add to the cooling effect from earlier eruptions of Cosaguina in 1835 and Askja in 1875. The temperature charts all show rapid rebound to equilibrium temperature for the region affected in a year or two at most.

Manns Map

Fourteen major volcanic eruptions, however, were recorded between 1883 and 1918 (Robock, 2000, and this essay). Some erupted for days or weeks and some were cataclysmic and shorter. The sum of all these eruptions from Krakatoa onward effected temperatures early in the instrumental age. Judging from wasting glaciers in the Alps, abrupt retreat began about 1860).

Manns Conclusions:
1)Four of these time series (Albany, Harrisburg, Chicago and Key West) show recovery to the range of today’s temperatures by 1870 before the eruption of Askja in 1875. The temperature rebounded very quickly after the Little Ice Age in the northern hemisphere.

Manns ENSO Map

2)Volcanic eruptions and unrelated huge swings shown from ENSO largely rule global temperature. Volcanic history and the El Nino Southern Oscillation (ENSO) trump all other increments of temperature that may be hidden in the lists.

3)The sum of the eruptions from Krakatoa (1883) to Katla (1918) and Cerro Azul (1932) was a cold start for climate models.

4)It is beyond doubt that academic and bureau climate models use data that was gathered when volcanic activity had depressed global temperature. The cluster from Krakatoa to Katla (1883 -1918) were global.

5)Modern events, Mount Saint Helens and Pinatubo, moreover, were a fraction of the event intensity of the late 19th and early 20th centuries eruptions.

6) The demise of frequent violent volcanos has allowed the planet to regress toward a norm (for now).

Summary

These findings describe a natural process by which a series of volcanoes along with a period of quiet solar cycles ended the Medieval Warm Period (MWP), chilling the land and inducing deep oceanic cooling resulting in the Little Ice Age. With much less violent volcanic activity in the 20th century, coincidental with typically active solar cycles, a Modern Warm Period ensued with temperatures rebounding back to approximately the same as before the LIA.

This suggests that humans and the biosphere were enhanced by a warming process that has ended. The solar cycles are again going quiet and are forecast to continue that way. Presently, volcanic activity has been routine, showing no increase over the last 100 years. No one knows how long will last the current warm period, a benefit to us from the ocean recovering after the LIA. But future periods are as likely to be cooler than to be warmer compared to the present.

Update on Warming Hiatus

Posted on by Ron Clutz

Figure 1. Comparison of HadCRUT3 and the latest HadCRUT4.6 Notice how all trends pivot around the 1998 El Nino peak.

Clive Best has a new post exploring the question: Whatever happened to the Global Warming Hiatus ? Excerpts in italics with my bolds and comment at end.

The last IPCC assessment in 2013 showed a clear pause in global warming lasting 16 years from 1998 to 2012 – the notorious hiatus. As a direct consequence of this AR5 estimates of climate sensitivity were reduced and CMIP5 models appeared to clearly overestimate trends. Following the first release of HadCRUT4 in 2014 the ‘headline’ then was that 2005 and 2010 were marginally warmer than 1998. This was the first dent in removing the hiatus. Since then each new version of H4 has showed further incremental warming trends, such that by 2019 the hiatus has now completely vanished. Anyone mentioning it today is likely to be ridiculed by the climate science community. So how did this reversal happen within just 5 years? I decided to find out exactly why the post 1998 temperature record changed so dramatically in such a short period of time.

In what follows I always use the same algorithm as CRU for the station data and then blend that with the Hadley SST data. I have checked that I can reproduce exactly the latest HadCRUT4.6 results based on the current 7820 stations from CRU merged with HadSST3. Back in 2012 I downloaded the original station data from CRU – CRUTEM3. I have also downloaded the latest CRUTEM4 station data.

Figure 1 above compares the latest HadCRUT4.6 results with the last version of HadCRUT3.

I had assumed that the reason for the apparent trend change was because CRUTEM4 had added many new weather stations in the Arctic (removing some in S.America as well), while additionally the SST data had also been updated (HadSST2 moved to HADSST3). However, as I show below, my assumption simply isn’t true.

To investigate I recalculated a ‘modern’ version of HadCRUT3 by using only the original 4100 stations (used by CRUTEM3) from CRUTEM4 station data.  The list of these stations are defined here. I then merged these with  both the older HadSST2 and HADSST3 to derive annual global temperature anomalies. Figure 2 shows the result. I get almost exactly the same values as the full 7820 stations in HadCRUT4. It certainly does not reproduce HadCRUT3 !

Figure 2. The black curve is based on “modern” CRUTEM3 stations combined with HADSST3 and the Yellow curve is “modern” CRUTEM3 stations with HADSST2

This result provides two conclusions.

  1. Modern CRUTEM3 stations give a different result to the original CRUTEM3 stations.
  2. SST data is not responsible for the difference between HadCRUT4 and HadCRUT3

    To confirm point 1) I used exactly the same code to regenerate HadCRUT3 temperature series using the original CRUTEM3 station data as opposed to the ‘modern’ values based on CRUTEM4.
Figure 3: Comparison of HadCRUT3 with my calculation using the original CRUTEM3 station data.

The original CRUTEM3 station data I had previously downloaded in 2012. These are combined with HADSST2 data. Now we see that the agreement with the H3 annual temperatures is very good, and indeed reproduces the hiatus.

So the conclusion is very simple. The monthly temperature values in over 4000 CRUTEM3 stations have all been continuously changed, and it is these changes alone that have resulted in transforming the 16 year long hiatus in global warming into a rising temperature trend. Furthermore all these updates have only affected temperatures AFTER 1998! Temperatures before 1998 have hardly changed at all, which is the second requirement needed to eliminate the hiatus.

P.S. I am sure there are excellent arguments as to why pair-wise ‘homogenisation’ is wonderful but why then does it only affect data after 1998 ?

Comment:

Meanwhile, UAH is showing a return to the mean annual anomaly since 1995.

We are Ignored, then Dissed, then Debated, then We Win.

Posted on by Ron Clutz

Global Warming Debate Soho Forum May 8, 2019

The post title is a reference to a quote from Mahatma Gandhi who said, when facing overwhelming odds opposed by an entrenched establishment in India:

Watch: Skeptical scientist wins rare New York City climate debate against warmist scientist – Audience flips from warmist views to skeptical after debate (H/T John Ray at his blog Greenie Watch)Excerpts in italics with my bolds.

The Soho Forum, Published on May 6, 2019

Resolution: There is little or no rigorous evidence that rising concentrations of carbon dioxide are causing dangerous global warming and threatening life on the planet.

For the affirmative:

Craig Idso is the founder, former president, and currently chairman of the Center for the Study of Carbon Dioxide and Global Change. The Center was founded in 1998 as a non-profit public charity dedicated to discovering and disseminating scientific information pertaining to the effects of atmospheric carbon dioxide enrichment on climate and the biosphere.

Dr. Idso’s research has appeared many times in peer-reviewed journals, and is the author or coauthor of several books, including The Many Benefits of Atmospheric CO2 Enrichment (Vales Lake Publishing, LLC, 2011), CO2, Global Warming and Coral Reefs (Vales Lake Publishing, LLC, 2009).

Dr. Idso also serves as an adjunct scholar for the Cato Institute and as a policy advisor for the CO2Coalition, the Heartland Institute and the Committee For A Constructive Tomorrow.

For the negative:

Jeffrey Bennett is an astrophysicist and educator. He has focused his career on math and science literacy. He is the lead author of bestselling college textbooks in astronomy, astrobiology, mathematics, and statistics, and of critically acclaimed books for the general public on topics including Einstein’s theory of relativity, the search for extraterrestrial life, and the importance of math to our everyday lives.

Other career highlights include serving two years as a Visiting Senior Scientist at NASA Headquarters, proposing and helping to develop the Voyage Scale Model Solar System that resides on the National Mall in Washington, DC, and creating the freeTotality app that has helped tens of thousands of people learn how to view a total solar eclipse.

His book A Global Warming Primeris posted freely online at http://www.globalwarmingprimer.com.

Moderator: “We have the final vote. The yes vote on the resolution that there is no evidence that’s causing dangerous global warming: It began at 24% (of the skeptical yes vote supporting that position) and it went up to 46% (after the debate). So [skeptical argument] gained 22% points. That’s the number to beat (46%).

The no resolution (warmist position) started at 29%. It went up to 41% or up 11 points.” The winner of the debate is skeptical scientist Dr. Craig Idso with his resolution asserting that “There is little or no rigorous evidence that rising concentrations of carbon dioxide are causing dangerous global warming and threatening life on the planet.”

Flashback 2007: Scientific Smackdown: Skeptics Voted The Clear Winners Against Global Warming Believers in Heated NYC Debate – RealClimate.org’s Gavin Schmidt appeared so demoralized that he mused that debates equally split between believers of a climate ‘crisis’ and scientific skeptics are probably not “worthwhile” to ever agree to again.

The 2007 Debate was on the statement: Global Warming is not a Crisis. Clips, Transcripts and Results are here :
https://www.intelligencesquaredus.org/debates/global-warming-not-crisis

December 1, 2009, was the Munk Debate on the statement: Be it resolved, climate change is mankind’s defining crisis, and demands a commensurate response… 
PRO George Monbiot, Elizabeth May 
CON Bjørn Lomborg, Lord Nigel Lawson
RESULT CON gains 8%. CON wins
See: https://munkdebates.com/debates/climate-change

More Recent is the March 2020 Karoly/Tamblyn–Happer Dialogue on Global Warming at The Best Schools

Drs. Karoly and Happer argued the following theses:

Dr. Karoly: Science has established that it is virtually certain that increases of atmospheric CO2 due to burning of fossil fuels will cause climate change that will have substantial adverse impacts on humanity and on natural systems. Therefore, immediate, stringent measures to suppress the burning of fossil fuels are both justified and necessary.

Dr. Happer: There is no scientific basis for the claim that increases of atmospheric CO2 due to burning of fossil fuels will cause climate change that will have substantial adverse impacts on humanity and on natural systems. If fossil fuels are burnt responsibly to limit real pollutants like fly ash, oxides of nitrogen or sulfur, heavy metals, etc., the CO2 released will be a benefit to the world. Any resulting climate change will be moderate, and there will be very major benefits to agriculture and other plant life.

When did global warming start?

Posted on by Ron Clutz

Here is the answer provided by Steve Maley on Quora. The response is in italics with my bolds and images.

Fig. 10. The 105 year time series of filtered monthly average temperatures (ºC) for the Des Moines, IA station plotted a) versus time in months (years also added) b) first derivative of temperature (ºC mo-1) versus temperature (ºC) c), and d) as power spectra, with the ordinate displaying the relative magnitude or power of the Fourier and wavelet coefficients, respectively, and the abscissa displaying the period of each cycle in years. In addition, the 95% confidence level against the white noise background continuum is shown by the dashed line.

Global Warming began in Muncie, Indiana on June 17, 1953 at 2:30 in the afternoon. It was a Tuesday.

Up until that time, weather was “average” all the time.

That is, except for the Dust Bowl, the Little Ice Age, Medieval Warm Period, etc.

Up until then, people had ideal, sustainable lifestyles. 90% of men spent all day in the fields looking at the backsides of two mules. Their spare time was spent chopping wood in hopes they could make it through another winter.

Women stayed at home and had babies. They had to have 8–10 because 2 or 3 of them wouldn’t live to see their 10th birthday.

Farm to Table was a thing. Since nobody had any money, it was a choice between raising your own food or starving.

Yes, it was an idyllic lifestyle. Damn fossil fuels screwed it all up.

How? By changing the atmosphere. Gases other than CO2 used to be 99.97% of the air we breathe. Now it’s 99.96%.

The horror.

Climate Models on Fire!

Posted on by Ron Clutz

They are at it again: Our future will be filled with death and destruction according to climate models. The latest doomsday scenario is that every summer in the future will be hotter than the one before, brought to you by CNN: “All the Fear All the Time.”

Future summers will ‘smash’ temperature records every year says CNN. Excerpts in italics with my bolds.

If you think it’s hot now, you haven’t seen anything yet. A new study predicts that parts of the world will “smash” temperature records every year in the coming century due to climate change, “pushing ecosystems and communities beyond their ability to cope.”

The scientists who authored the study, published in the journal Nature Climate Change on Monday, used 22 climate models to game out exactly how hot these summer temperatures would be. They determined that by the end of the 21st century, future temperature events “will be so extreme that they will not have been experienced previously.”

The temperature increase is directly tied to rising global greenhouse gas emissions, the authors say.

The world is already seeing record setting temperatures and while warming hasn’t been uniform, earlier studies have shown that the planet has been in a warming trend, generally.

Heat waves will be deadly. Heat stroke, breathing issues, heart attacks, asthma attacks, kidney problems are all a big concern for people when the temperatures increase, according to the US Centers for Disease Control and Prevention.

Higher temperatures can also make air pollution worse, make water scarce and cause crops to fail, leading to malnutrition and starvation.

In 2014, the World Health Organization predicted 250,000 more people will die annually between 2030 and 2050 due to climate change. More recent studies predict that this is a “conservative estimate.”

If, however, countries meet goals of limiting global temperature rise less than 2 degrees Celsius, as set out in the Paris agreement, that scenario would be much less likely.

Footnote: A second separate heat wave alarm study was published and trumpeted in the Seattle Times. (H/T kakatoa, comment below) Cliff Mass does his usual thorough review pointing out problems both in the estimating of future temperatures and in calculating projected deaths from heat waves.

The article by Mass is The Seattle Times Story on Massive Heat Wave Deaths in Seattle: Does it Make Sense?


Trudeau’s Empty Plastic Gesture

Posted on by Ron Clutz

Bjorn Lomborg writes in the Globe and Mail about Canadian PM Justin Treudeau showing off by proposing to ban single-use plastics. Sorry, banning plastic bags won’t save our planet. Excerpts in italics with my bolds.

Last week, Prime Minister Justin Trudeau announced a plan to reduce plastic pollution, which will include a ban on single-use plastics as early as 2021. This is laudable: plastics clog drains and cause floods, litter nature and kill animals and birds.

Of course, plastic also makes our lives better in a myriad of ways. In just four decades, plastic packaging has become ubiquitous because it keeps everything from cereals to juice fresher and reduces transportation losses, while one-use plastics in the medical sector have made syringes, pill bottles and diagnostic equipment more safe.

Going without disposable plastic entirely would leave us worse off, so we need to tackle the problems without losing all of the benefits.

The simplest action for consumers is to ensure that plastic is collected and used, so a grocery bag, for example, has a second life as a trash bag, and is then used for energy.

But we need to be honest about how much consumers can achieve. As with other environmental issues, instead of tackling the big-picture problems to actually reduce the plastic load going into oceans, we focus on relatively minor changes involving consumers, meaning we only ever tinker at the margins.

More than 20 countries have taken the showy action of banning plastic bags, including even an al-Qaeda-backed terrorist group which said plastic bags pose “a serious threat to the well-being of humans and animals alike.”

But even if every country banned plastic bags it would not make much of a difference, since plastic bags make up less than 0.8 per cent of the mass of plastic currently afloat on the world’s oceans.

Rather than trying to save the oceans with such bans in rich countries, we need to focus on tackling the inferior waste management and poor environmental policies in developing regions.

Research from 2015 shows that less than 5 per cent of land-based plastic waste going into the ocean comes from OECD countries, with half coming from just four countries: China, Indonesia, Philippines and Vietnam. While China already in 2008 banned thin plastic bags and put a tax on thicker ones, it is estimated to contribute more than 27 per cent of all marine plastic pollution originating from land.

Moreover, banning plastic bags can have unexpected, inconvenient results. A new study shows California’s ban eliminates 40 million pounds of plastic annually. However, many banned bags would have been reused for trash, so consumption of trash bags went up by 12 million pounds, reducing the benefit. It also increased consumption of paper bags by twice the saved amount of plastic – 83 million pounds. This will lead to much larger emissions of CO₂.

When Kenya banned plastic bags, people predictably shifted to thicker bags made of synthetic fabric – which now may be banned. But Kenya had to relent and exempt plastics used to wrap fresh foods such as meat and other products.

We also need to consider the wider environmental impact of our bag choices. A 2018 study by the Danish Ministry of Environment and Food looked not just at plastic waste, but also at climate-change damage, ozone depletion, human toxicity and other indicators. It found you must reuse an organic cotton shopping bag 20,000 times before it will have less climate damage than a plastic bag.

If we use the same shopping bag every single time we go to the store, twice every week, it will still take 191 years before the overall environmental effect of using the cotton bag is less than if we had just used plastic.

Even a simple paper bag requires 43 reuses to be better for the environment – far beyond the point at which the bag will be fit for the purpose.

The study clearly shows that a simple plastic bag, reused as a trash bag, has the smallest environmental impact of any of the choices.

If we want to reduce the impact of plastic bags while still allowing for their efficient use, a tax seems like a much better idea. A 2002 levy in Ireland reduced plastic bag use from 328 bags a person per year to just 21 bags.

And if we really want to make a meaningful impact on ocean plastics coming from land, we should focus on the biggest polluters such as China, Indonesia, Philippines and Vietnam, and emphasize the most effective ways to cut the plastic load, namely better waste management in the developing world.

We should also recognize that more than 70 per cent of all plastics floating on oceans today – about 190,000 tonnes – come from fisheries, with buoys and lines making up the majority. That tells us clearly that concerted action is needed to clean up the fishing industry.

If our goal is to get a cleaner ocean, we should by all means think about actions we can take as consumers in rich countries to reduce our use of unnecessary plastic bags. But we need to keep a sense of proportion and, if we’re serious, focus on change where it’s really needed.

Bjorn Lomborg is president of the Copenhagen Consensus Center.

See Also Plastic Trash Talking

Waste Management Saves the Ocean

Upside Down CO2 Dogma

Posted on by Ron Clutz

Yoga experts taking the IPCC position attributing rising CO2 to humans.

In the field of climatology, we see repeatedly that alarmists/activists turn things upside down to justify a narrative.  Causes and effects are reversed in order to foster alarm about the burning of fossil fuels.  This distorted way of thinking is described in more detail in essays linked at the end.  This post is concerned with one particular reversal of reality, namely the assertion by IPCC adherents that atmospheric CO2 is rising entirely because of emissions from fossil fuels.  They have it upside down:  Rising temperatures are the main reason CO2 is rising, not the other way around.

The latest heads up treatise on this issue is published this week at Earth Sciences Journal What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations by Hermann Harde, Experimental Physics and Materials Science, Helmut-Schmidt-University, Hamburg, Germany.  Excerpts in italics with my bolds.

Harde (2019) Conclusion

The increase of CO2 over recent years can well be explained by a single balance equation, the Conservation Law (23) which considers the total atmospheric CO2 cycle, consisting of temperature and thus time dependent natural emissions, the human activities and a temperature dependent uptake process, which scales proportional with the actual concentration. This uptake is characterized by a single time scale, the residence time of about 3 yr, which over the Industrial Era slightly increases with temperature.

Only this concept is in complete conformity with all observations and natural causalities. It confirms previous investigations (Salby [7, 10]; Harde [6]) and shows the key deficits of some widespread but largely ad hoc carbon cycle models used to describe atmospheric CO2, failures which are responsible for the fatal conclusion that the increase in atmospheric CO2 over the past 270 years is principally anthropogenic.

GHG blocks

 

For a conservative assessment we find from Figure 8 that the anthropogenic contribution to the observed CO2 increase over the Industrial Era is significantly less than the natural influence. At equilibrium this contribution is given by the fraction of human to native impacts. As an average over the period 2007-2016 the anthropogenic emissions (FFE&LUC together) donated not more than 4.3% to the total concentration of 393 ppm, and their fraction to the atmospheric increase since 1750 of 113 ppm is not more than 17 ppm or 15%. With other evaluations of absorption, the contribution from anthropogenic emission is even smaller.
[Note:  FFE is Fossil Fuel Emissions, LUC is Land Use Change]

Thus, not really anthropogenic emissions but mainly natural processes, in particular the temperature, have to be considered as the dominating impacts for the observed CO2 increase over the last 270 yr and also over paleoclimate periods.

[Read the entire paper for discussion of the error-prone CO2 models employed by IPCC]

Background from Previous Post:  Who to Blame for Rising CO2?

Blaming global warming on humans comes down to two assertions:

Rising CO2 in the atmosphere causes earth’s surface temperature to rise.

Humans burning fossil fuels cause rising atmospheric CO2.

For this post I will not address the first premise, instead refer the reader to a previous article regarding efforts to measure temperature effects from CO2. Greenhouse gas theory presumes surface warming arises because heat is forced to escape at a higher, colder altitude. However, at least four separate studies of the available datasets were not able to detect any shift in the atmospheric temperature profile coincidental with rising CO2 in recent decades.  The discussion of the GHG warming theory and its lack of evidence in the real world is summarized in the post No GHG Warming Fingerprints in the Sky

The focus in this piece is the claim that fossil fuel emissions drive observed rising CO2 concentrations. IPCC consensus scientists and supporters note that human emissions are about twice the measured rise and presume that natural sinks absorb half, leaving the other half to accumulate in the atmosphere. Thus they conclude all of the increase in atmospheric CO2 is from fossil fuels.

This simple-minded conclusion takes the only two things we measure in the carbon cycle: CO2 in the atmosphere, and fossil fuel emissions. And then asserts that one causes the other. But several elephants are in the room, namely the several carbon reservoirs that dwarf human activity in their size and activity, and can not be measured because of their complexity.

The consensus notion is based on a familiar environmental paradigm: The Garden of Eden. This is the modern belief that nature, and indeed the climate is in balance, except for humans disrupting it by their activities. In the current carbon cycle context, it is the supposition that all natural sources and sinks are in balance, thus any additional CO2 is because of humans.

Now, a curious person might wonder: How is it that for decades as the rate of fossil fuel emissions increased, the absorption by natural sinks has also increased at exactly the same rate, so that 50% is always removed and 50% remains? It can only be that nature is also dynamic and its flows change over time!

That alternative paradigm is elaborated in several papers that are currently under vigorous attack from climatists. As one antagonist put it: Any paper concluding that humans don’t cause rising CO2 is obviously wrong. One objectionable study was published by Hermann Harde, another by Ole Humlum, and a third by Ed Berry is delayed in pre-publication review.

The methods and analyses are different, but the three skeptical papers argue that the levels and flows of various carbon reservoirs fluctuate over time with temperature itself as a causal variable. Some sinks are stimulated by higher temperatures to release more CO2 while others respond by capturing more CO2. And these reactions occur on a range of timescales. Once these dynamics are factored in, the human contribution to rising atmospheric CO2 is neglible, much to the ire of alarmists.

Ed Berry finds IPCC carbon cycle metrics illogical.

Dr. Ed Berry provides a preprint of his submitted paper at a blog post entitled Why human CO2 does not change climate. He welcomes comments and uses the discussion to revise and improve the text. Excerpts with my bolds.

The United Nations Intergovernmental Panel on Climate Change (IPCC) claims human emissions raised the carbon dioxide level from 280 ppm to 410 ppm, or 130 ppm. Physics proves this claim is impossible.

The IPCC agrees today’s annual human carbon dioxide emissions are 4.5 ppm per year and nature’s carbon dioxide emissions are 98 ppm per year. Yet, the IPCC claims human emissions have caused all the increase in carbon dioxide since 1750, which is 30 percent of today’s total.

How can human carbon dioxide, which is only 5 percent of natural carbon dioxide, add 30 percent to the level of atmospheric carbon dioxide? It can’t.

This paper derives a Model that shows how human and natural carbon dioxide emissions independently change the equilibrium level of atmospheric carbon dioxide. This Model should replace the IPCC’s invalid Bern model.

The Model shows the ratio of human to natural carbon dioxide in the atmosphere equals the ratio of their inflows, independent of residence time.

Fig. 5. The sum of nature’s inflow is 20 times larger than the sum of human emissions. Nature balances inflow with or without human emissions.

The model shows, contrary to IPCC claims, that human emissions do not continually add carbon dioxide to the atmosphere, but rather cause a flow of carbon dioxide through the atmosphere. The flow adds a constant equilibrium level, not a continuing increasing level, of carbon dioxide.

 

Fig. 2. Balance proceeds as follows: (1) Inflow sets the balance level. (2) Level sets the outflow. (3) Level moves toward balance level until outflow equals inflow.

Ole Humlum proves that CO2 follows temperature also for interannual/decadal periods.

Humlum et al. looks the modern record of fluctuating temperatures and atmospheric CO2 and concludes that CO2 changes follow temperature changes over these timescales. The paper is The phase relation between atmospheric carbon dioxide and global temperature OleHumlum, KjellStordahl, Jan-ErikSolheim.  Excerpts with my bolds.

From the Abstract:
Using data series on atmospheric carbon dioxide and global temperatures we investigate the phase relation (leads/lags) between these for the period January 1980 to December 2011. Ice cores show atmospheric CO2 variations to lag behind atmospheric temperature changes on a century to millennium scale, but modern temperature is expected to lag changes in atmospheric CO2, as the atmospheric temperature increase since about 1975 generally is assumed to be caused by the modern increase in CO2.

In our analysis we used eight well-known datasets. . . We find a high degree of co-variation between all data series except 7) and 8), but with changes in CO2 always lagging changes in temperature.

Highlights
► Changes in global atmospheric CO2 are lagging 11–12 months behind changes in global sea surface temperature. ► Changes in global atmospheric CO2 are lagging 9.5–10 months behind changes in global air surface temperature. ► Changes in global atmospheric CO2 are lagging about 9 months behind changes in global lower troposphere temperature. ► Changes in ocean temperatures explain a substantial part of the observed changes in atmospheric CO2 since January 1980. ► Changes in atmospheric CO2 are not tracking changes in human emissions.

Summary

Summing up, monthly data since January 1980 on atmospheric CO2 and sea and air temperatures unambiguously demonstrate the overall global temperature change sequence of events to be 1) ocean surface, 2) surface air, 3) lower troposphere, and with changes in atmospheric CO2 always lagging behind changes in any of these different temperature records.9

A main control on atmospheric CO2 appears to be the ocean surface temperature, and it remains a possibility that a significant part of the overall increase of atmospheric CO2 since at least 1958 (start of Mauna Loa observations) simply reflects the gradual warming of the oceans, as a result of the prolonged period of high solar activity since 1920 (Solanki et al., 2004).

Based on the GISP2 ice core proxy record from Greenland it has previously been pointed out that the present period of warming since 1850 to a high degree may be explained by a natural c. 1100 yr periodic temperature variation (Humlum et al., 2011).

Hermann Harde sets realistic proportions for the carbon cycle.

Hermann Harde applies a comparable perspective to consider the carbon cycle dynamics. His paper is Scrutinizing the carbon cycle and CO2 residence time in the atmosphere. Excerpts with my bolds.

From the Abstract:

Climate scientists presume that the carbon cycle has come out of balance due to the increasing anthropogenic emissions from fossil fuel combustion and land use change. This is made responsible for the rapidly increasing atmospheric CO2 concentrations over recent years, and it is estimated that the removal of the additional emissions from the atmosphere will take a few hundred thousand years. Since this goes along with an increasing greenhouse effect and a further global warming, a better understanding of the carbon cycle is of great importance for all future climate change predictions. We have critically scrutinized this cycle and present an alternative concept, for which the uptake of CO2 by natural sinks scales proportional with the CO2 concentration. In addition, we consider temperature dependent natural emission and absorption rates, by which the paleoclimatic CO2 variations and the actual CO2 growth rate can well be explained. The anthropogenic contribution to the actual CO2 concentration is found to be 4.3%, its fraction to the CO2 increase over the Industrial Era is 15% and the average residence time 4 years.
Fig. 1. Simplified schematic of the global carbon cycle. Black numbers and arrows indicate reservoir mass in PgC and exchange fluxes in PgC/yr before the Industrial Era. Red arrows and numbers show annual  anthropogenic’ flux changes averaged over the 2000–2009 time period. Graphic from AR5-Chap.6-Fig.6.1. 

Conclusions

Climate scientists assume that a disturbed carbon cycle, which has come out of balance by the increasing anthropogenic emissions from fossil fuel combustion and land use change, is responsible for the rapidly increasing atmospheric CO2 concentrations over recent years. While over the whole Holocene up to the entrance of the Industrial Era (1750) natural emissions by heterotrophic processes and fire were supposed to be in equilibrium with the uptake by photosynthesis and the net ocean-atmosphere gas exchange, with the onset of the Industrial Era the IPCC estimates that about 15–40% of the additional emissions cannot further be absorbed by the natural sinks and are accumulating in the atmosphere. The IPCC further argues that CO2 emitted until 2100 will remain in the atmosphere longer than 1000 years, and in the same context it is even mentioned that the removal of human-emitted CO2 from the atmosphere by natural processes will take a few hundred thousand years (high confidence) (see AR5-Chap.6ExecutiveSummary). Since the rising CO2 concentrations go along with an increasing greenhouse effect and, thus, a further global warming, a better understanding of the carbon cycle is a necessary prerequisite for all future climate change predictions.

In their accounting schemes and models of the carbon cycle the IPCC uses many new and detailed data which are primarily focussing on fossil fuel emission, cement fabrication or net land use change (see AR5-WG1- Chap.6.3.2), but it largely neglects any changes of the natural emissions, which contribute to more than 95 % to the total emissions and by far cannot be assumed to be constant over longer periods (see, e.g.: variations over the last 800,000 years (Jouzel et al., 2007); the last glacial termination (Monnin et al., 2001); or the younger Holocene (Monnin et al., 2004; Wagner et al., 2004)).

Since our own estimates of the average CO2 residence time in the atmosphere differ by several orders of magnitude from the announced IPCC values, and on the other hand actual investigations of Humlum et al. (2013) or Salby (2013, 2016) show a strong relation between the natural CO2 emission rate and the surface temperature, this was motivation enough to scrutinize the IPCC accounting scheme in more detail and to contrast this to our own calculations.

Different to the IPCC we start with a rate equation for the emission and absorption processes, where the uptake is not assumed to be saturated but scales proportional with the actual CO2 concentration in the atmosphere (see also Essenhigh, 2009; Salby, 2016). This is justified by the observation of an exponential decay of 14C. A fractional saturation, as assumed by the IPCC, can directly be expressed by a larger residence time of CO2 in the atmosphere and makes a distinction between a turnover time and adjustment time needless.

Based on this approach and as solution of the rate equation we derive a concentration at steady state, which is only determined by the product of the total emission rate and the residence time. Under present conditions the natural emissions contribute 373 ppm and anthropogenic emissions 17 ppm to the total concentration of 390 ppm (2012). For the average residence time we only find 4 years.

The stronger increase of the concentration over the Industrial Era up to present times can be explained by introducing a temperature dependent natural emission rate as well as a temperature affected residence time. With this approach not only the exponential increase with the onset of the Industrial Era but also the concentrations at glacial and cooler interglacial times can well be reproduced in full agreement with all observations.

So, different to the IPCC’s interpretation the steep increase of the concentration since 1850 finds its natural explanation in the self accelerating processes on the one hand by stronger degassing of the oceans as well as a faster plant growth and decomposition, on the other hand by an increasing residence time at reduced solubility of CO2 in oceans. Together this results in a dominating temperature controlled natural gain, which contributes about 85% to the 110 ppm CO2 increase over the Industrial Era, whereas the actual anthropogenic emissions of 4.3% only donate 15%. These results indicate that almost all of the observed change of CO2 during the Industrial Era followed, not from anthropogenic emission, but from changes of natural emission. The results are consistent with the observed lag of CO2 changes behind temperature changes (Humlum et al., 2013; Salby, 2013), a signature of cause and effect. Our analysis of the carbon cycle, which exclusively uses data for the CO2 concentrations and fluxes as published in AR5, shows that also a completely different interpretation of these data is possible, this in complete conformity with all observations and natural causalities.

On Myopic, Lop-sided Climatism

Fearless Physics from Dr. Salby

Climate Reductionism

More on CO2

CO2 Fluxes, Sources and Sinks

Obsessed with Human CO2

Not Worried About CO2

May Makes Both Land and Sea Cooler

Posted on by Ron Clutz

banner-blog

With apologies to Paul Revere, this post is on the lookout for cooler weather with an eye on both the Land and the Sea.  UAH has updated their tlt (temperatures in lower troposphere) dataset for May.   Previously I have done posts on their reading of ocean air temps as a prelude to updated records from HADSST3. This month also has a separate graph of land air temps because the comparisons and contrasts are interesting as we contemplate possible cooling in coming months and years.

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.  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 technical enhancement to HadSST3 delayed March and April updates, May has just been posted, hopefully a signal the future months will also appear more promptly.  For comparison we can look at lower troposphere temperatures (TLT) from UAHv6 which are now posted for May. The temperature record is derived from microwave sounding units (MSU) on board satellites like the one pictured above. Last month also involved 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 new 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 temps since January 2015.

May ocean air temps dropped in all regions after April’s rise, resulting in the Global average back down below January 2019.  NH warming in February has been reversed, and April warming in SH and the Tropics is also gone.  The temps this May are warmer than 2018, but lower than 05/2017, and of course lower than 2016.

Land Air Temperatures Tracking Downward 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 record air temps at 2 meters above ground.  UAH gives tlt anomalies for air over land separately from ocean air temps.  The graph updated for May is below.

The greater volatility of the Land temperatures was evident earlier, but has calmed down recently. Also the  NH dominates, having twice as much land area as SH.  Note how global peaks mirror NH peaks.  In January 2019 all Land air temps were close but have now diverged.  In May both SH and the Tropics dropped sharply (comparable to ocean temps), and the much larger NH land surface also cooled, pulling the Global anomaly down nearly 0.2C.  The Tropical land air temps could not be more different from 05/2018, yet the Global, NH and SH are much cooler.

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, now more than 1C lower than the peak in 2016.  TLT measures started the recent cooling later than SSTs from HadSST3, but are now showing the same pattern.  It seems obvious that despite the three El Ninos, their warming has not persisted, and without them it would probably have cooled since 1995.  Of course, the future has not yet been written.