Oceans Make Climate

Ocean Surface Temps–How Low Will They Go?

Posted on by Ron Clutz

 

Ocean temperature measurements come from a global array of 3,500 Argo floats and other ocean sensors. Credits: Argo Program, Germany/Ifremer

We have seen lots of claims about the temperature records for 2016 and 2015 proving dangerous man made warming.  At least one senator stated that in a confirmation hearing.  Now that HadSST3 data is complete through February 2017, let’s see how obvious is the ocean’s governing of global average temperatures.

The best context for understanding these last two years 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 the last two years.

HadSST is generally regarded as the best of the global SST data sets, and so the temperature story here comes from that source, the latest version being HadSST3.

The chart below shows the last two years of SST monthly anomalies as reported in HadSST3, along with the first two months of 2017.

Note that higher temps in 2015 and 2016 are first of all due to a sharp rise in Tropical SST, beginning in March 2015, peaking in February 2016, and steadily declining back to its beginning level. Secondly, the Northern Hemisphere added two bumps on the shoulders of Tropical warming, with peaks in August of each year. Also, note that the global release of heat was not dramatic, due to the Southern Hemisphere offsetting the Northern one.

Finally, the oceans are starting 2017 only slightly lower than a year ago, but this year with much cooler Tropics.  Notice that both the Tropics and also the Northern Hemisphere continue to cool.  The Global average warmed slightly, pulled upward by the Southern Hemisphere which reaches its summer peak at this time.

March may repeat 2016 when NH bottomed and SH peaked, or maybe both will rise or both will drop.  In the latter case, perhaps we will see the long-awaited La Nina.

H/T to Global Warming Policy Forum for adding this informative graphic:
|floatcyclescaled

Much ado has been made of this warming, including claims of human causation, despite the obvious oceanic origin. However, it is unreasonable to claim CO2 functions as a global warming agent, yet the two hemispheres respond so differently.  Moreover, CO2 warming theory expects greater warming in the higher latitudes, while this event was driven by heating in the Tropics, contradicting alarmist warming theory.

Solar energy accumulates massively in the ocean and is variably released during circulation events.

 

Honey, I Shrunk the Arctic Ice! Not.

Posted on by Ron Clutz

Image is from Honey, I Shrunk the Kids, a 1989 American science fiction family film produced by Walt Disney Pictures.

The notion that man-made global warming causes Arctic ice to melt took a major hit with a recent publication.  The article is Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice by Qinghua Ding, Axel Schweiger, Michelle L’Heureux, David S. Battisti, Stephen Po-Chedley, Nathaniel C. Johnson, Eduardo Blanchard-Wrigglesworth, Kirstin Harnos, Qin Zhang, Ryan Eastman & Eric J. Steig.  (Warning: Reliability of published papers diminishes as numbers of co-authors increases.)

The paper was published online by Nature Climate Change on 13 March 2017. It is behind a paywall, but the reactions to it are revealing.  The abstract says:

The Arctic has seen rapid sea-ice decline in the past three decades, whilst warming at about twice the global average rate. Yet the relationship between Arctic warming and sea-ice loss is not well understood. Here, we present evidence that trends in summertime atmospheric circulation may have contributed as much as 60% to the September sea-ice extent decline since 1979. A tendency towards a stronger anticyclonic circulation over Greenland and the Arctic Ocean with a barotropic structure in the troposphere increased the downwelling longwave radiation above the ice by warming and moistening the lower troposphere. Model experiments, with reanalysis data constraining atmospheric circulation, replicate the observed thermodynamic response and indicate that the near-surface changes are dominated by circulation changes rather than feedbacks from the changing sea-ice cover. Internal variability dominates the Arctic summer circulation trend and may be responsible for about 30–50% of the overall decline in September sea ice since 1979. (my bolds)

Announcements of the finding were welcomed by skeptics and lukewarmists as an indication that climatologists were taking off their CO2 blinders and at last admitting to natural forces internal to the climate system.  Some responses were:

Arctic Ice Loss Driven by Natural Swings

Arctic ice loss driven by natural swings, not just mankind

Study in journal Nature: HALF of Arctic ice loss driven by natural swings — not ‘global warming’

Arctic Ice Alarmists are finding themselves skating on thin ice, as evidenced by their articles attempting to control the damage.  Some of these titles are:

We Deserve Half the Blame for Declining Arctic Sea Ice (Discover)

Humans to blame for bulk of Arctic sea ice loss: study (Phys.org)

Human activity is driving retreat of Arctic sea ice (from the misnamed Skeptical Science blog)

Why Alarmists are Twisting in the Wind

The full paper is behind a paywall, but we have description of the method and content by the lead author in an article at Popular Science Up to half of the Arctic’s melt might be totally natural–But climate change is still responsible for the rest.  He begins with his profession of faith:

“Anthropogenic forcing is still dominant — it’s still the key player,” said first author Qinghua Ding, a climate scientist at the University of California Santa Barbara. . .”But we found that natural variability has helped to accelerate this melting, especially over the past 20 years.”  A colleague adds:  “The results of Ding et al. do not call into question whether human-induced warming has led to Arctic sea-ice decline – a wide range of evidence shows that it has”.

This is the shibboleth demanded from any and all scientists who do not wish to be called “deniers” and cast into the outer darkness.

Note: A shibboleth is an old belief or saying that is repetitively cited but untrue.  This meaning evolved from its earlier significance as a word or custom whose variations in pronunciation or style are used to distinguish members of ingroups from those of outgroups, with an implicit value judgment based on familiarity with the shibboleth.(Wikipedia)


“The tribe has spoken.  Time for you to go!”

What Ding et al. Studied

Ding goes on to describe the nature of their analysis. (From Popular Science)

“There is a mismatch between the model’s output and the observation,” said lead author Qinghua Ding, a professor in the Geography Department at the University of California Santa Barbara. “Observation shows very fast, very abrupt sea ice melting, whereas the climate model cannot capture the fast melting.”

To understand why, Ding and his team focused on the connection between September sea-ice extent (or how much of the Arctic sea had at least 15 percent sea ice) and the preceding summer’s (June-August) atmospheric circulation. Ding knew from earlier work that tropical circulation can affect seasonal variability of sea ice in the Arctic.

“In the model we turned off all CO2 forcing,” said Ding, or all climate changes that were “forced” by the addition of carbon dioxide into the atmosphere. “And we still got some sea ice melting, that was very similar to the observation.”

“If the circulation changes are caused by anthropogenic greenhouse warming (or other human or natural external forcings such as ozone depletion, aerosol emissions, or solar activity) this pattern of atmospheric change should emerge as a clear signature when averaging together many climate model simulations of this period,” Neil Swart, a Research Scientist with Environment and Climate Change Canada who wasn’t involved in the new study, wrote in an accompanying article.

But when Ding averaged the climate models together, the air circulation changes cancelled each other out—like a balanced equation. They only data that remained in the models was responding to external forcings, like greenhouse gas emissions. In other words, Ding found that between 30-50 percent of the arctic melting is due to these unforced, or non-climate change caused variations—and that with this factored in, the climate models were generally accurate. The increased rapidity of Arctic melting was due to natural variations outside of the scope of the climate change models.

What Can Be Learned from Ding et al.

First note that they are climate modelers studying the behavior of models when parameters are manipulated.  It is encouraging that they notice the incompleteness of their models leads to discrepancies from reality.  This is a step in the right direction.

Second, note that the CO2 forcing is actually their term for all external forcings, including solar, aerosols etc.  They seem to be blind to oceanic multi-decadal and multi-centennial oscillations.  They make a leap of faith when they attribute every factor outside of atmospheric circulation to CO2.

Others more comprehensive in their research have concluded that fluctuations in the ocean water structure drive both ice extent changes and atmospheric circulations. See Arctic Sea Ice: Self-Oscillating System featuring the work of V. F. Zakharov and others at the Arctic and Antarctic Research Institute in St. Petersburg.

Summary

Some climate modelers are undermining core beliefs even while using a flawed methodology based on studying models rather than nature itself. Alarmists are forced into scrambling to continue blaming humans for declining Arctic Sea Ice. When the effects of oceanic circulations are added to atmospheric effects, there is little influence left for CO2.

Spinning the papers to keep the narrative alive.

Footnote:

The abstract mentions downwelling longwave radiation, a theoretical effect that in practice is overwhelmed by massive heat transfers upward into space.

In the Arctic (and also at the South Pole), the air is in direct contact with an infinite heat sink: outer space. The tropopause (where radiative loss upward is optimized) is only 7 km above the surface at the poles in winter, compared to 20 km at the equator. There is no door to open or close; the air is constantly convecting any and all energy away from the surface for radiation into space.

Instead of an open door, Arctic ice melts when the sun climbs over the horizon. Both the water and air are warmed, and the ice cover retreats until sundown in Autumn.

Most people fail to appreciate the huge heat losses at the Arctic pole. Mark Brandon has an excellent post on this at his wonderful blog, Mallemaroking.

By his calculations the sensible heat loss in Arctic winter ranges 200-400 Wm2.

The annual cycle of sensible heat flux from the ocean to the atmosphere for 4 different wind speeds

As the diagram clearly shows, except for a short time in high summer, the energy flow is from the water heating the air.

“Then the heat loss over the 2×10^9 m2 of open water in that image is a massive 600 GW – yes that is Giga Watts – 600 x 10^9 Watts.

If you want to be really inappropriate then in 2 hours, that part of the ocean lost more energy than it takes to run the London Underground for one year.

Remember that is just one component and not the full heat budget – which is partially why it is inappropriate. For the full budget we have to include latent heat flux, long wave radiation, short wave radiation, energy changes through state changes when ice grows and decays, and so on. Also large heat fluxes lead to rapid sea ice growth which then insulates the ocean from further heat loss.”

 

 

 

 

Ocean Oxygen Misdirection

Posted on by Ron Clutz


The climate scare machine is promoting again the fear of suffocating oceans. For example, an article this week by Chris Mooney in Washington Post, It’s Official, the Oceans are Losing Oxygen.

A large research synthesis, published in one of the world’s most influential scientific journals, has detected a decline in the amount of dissolved oxygen in oceans around the world — a long-predicted result of climate change that could have severe consequences for marine organisms if it continues.

The paper, published Wednesday in the journal Nature by oceanographer Sunke Schmidtko and two colleagues from the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany, found a decline of more than 2 percent in ocean oxygen content worldwide between 1960 and 2010.

Climate change models predict the oceans will lose oxygen because of several factors. Most obvious is simply that warmer water holds less dissolved gases, including oxygen. “It’s the same reason we keep our sparkling drinks pretty cold,” Schmidtko said.

But another factor is the growing stratification of ocean waters. Oxygen enters the ocean at its surface, from the atmosphere and from the photosynthetic activity of marine microorganisms. But as that upper layer warms up, the oxygen-rich waters are less likely to mix down into cooler layers of the ocean because the warm waters are less dense and do not sink as readily.

And of course, other journalists pile on with ever more catchy headlines.

The World’s Oceans Are Losing Oxygen Due to Climate Change

How Climate Change Is Suffocating The Oceans

Overview of Oceanic Oxygen

Once again climate alarmists/activists have seized upon an actual environmental issue, but misdirect the public toward their CO2 obsession, and away from practical efforts to address a real concern. Some excerpts from scientific studies serve to put things in perspective.

How the Ocean Breathes

Variability in oxygen and nutrients in South Pacific Antarctic Intermediate Water by J. L. Russell and A. G. Dickson

The Southern Ocean acts as the lungs of the ocean; drawing in oxygen and exchanging carbon dioxide. A quantitative understanding of the processes regulating the ventilation of the Southern Ocean today is vital to assessments of the geochemical significance of potential circulation reorganizations in the Southern Hemisphere, both during glacial-interglacial transitions and into the future.

Traditionally, the change in the concentration of oxygen along an isopycnal due to remineralization of organic material, known as the apparent oxygen utilization (AOU), has been used by physical oceanographers as a proxy for the time elapsed since the water mass was last exposed to the atmosphere. The concept of AOU requires that newly subducted water be saturated with respect to oxygen and is calculated from the difference between the measured oxygen concentration and the saturated concentration at the sample temperature.

This study has shown that the ratio of oxygen to nutrients can vary with time. Since Antarctic Intermediate Water provides a necessary component to the Pacific equatorial biological regime, this relatively high-nutrient, high-oxygen input to the Equatorial Undercurrent in the Western Pacific plays an important role in driving high rates of primary productivity on the equator, while limiting the extent of denitrifying bacteria in the eastern portion of the basin. 

Uncertain Measures of O2 Variability and Linkage to Climate Change

A conceptual model for the temporal spectrum of oceanic oxygen variability by Taka Ito and Curtis Deutsch

Changes in dissolved O2 observed across the world oceans in recent decades have been interpreted as a response of marine biogeochemistry to climate change. Little is known however about the spectrum of oceanic O2 variability. Using an idealized model, we illustrate how fluctuations in ocean circulation and biological respiration lead to low-frequency variability of thermocline oxygen.

Because the ventilation of the thermocline naturally integrates the effects of anomalous respiration and advection over decadal timescales, shortlived O2 perturbations are strongly damped, producing a red spectrum, even in a randomly varying oceanic environment. This background red spectrum of O2 suggests a new interpretation of the ubiquitous strength of decadal oxygen variability and provides a null hypothesis for the detection of climate change influence on oceanic oxygen. We find a statistically significant spectral peak at a 15–20 year timescale in the subpolar North Pacific, but the mechanisms connecting to climate variability remain uncertain.

The spectral power of oxygen variability increases from inter-annual to decadal frequencies, which can be explained using a simple conceptual model of an ocean thermocline exposed to random climate fluctuations. The theory predicts that the bias toward low-frequency variability is expected to level off as the forcing timescales become comparable to that of ocean ventilation. On time scales exceeding that of thermocline renewal, O2 variance may actually decrease due to the coupling between physical O2 supply and biological respiration [Deutsch et al., 2006], since the latter is typically limited by the physical nutrient supply.

Climate Model Projections are Confounded by Natural Variability

Natural variability and anthropogenic trends in oceanic oxygen in a coupled carbon cycle–climate model ensemble by T. L. Frolicher et al.

Internal and externally forced variability in oceanic oxygen (O2) are investigated on different spatiotemporal scales using a six-member ensemble from the National Center for Atmospheric Research CSM1.4-carbon coupled climate model. The oceanic O2 inventory is projected to decrease significantly in global warming simulations of the 20th and 21st centuries.

The anthropogenically forced O2 decrease is partly compensated by volcanic eruptions, which cause considerable interannual to decadal variability. Volcanic perturbations in oceanic oxygen concentrations gradually penetrate the ocean’s top 500 m and persist for several years. While well identified on global scales, the detection and attribution of local O2 changes to volcanic forcing is difficult because of unforced variability.

Internal climate modes can substantially contribute to surface and subsurface O2 variability. Variability in the North Atlantic and North Pacific are associated with changes in the North Atlantic Oscillation and Pacific Decadal Oscillation indexes. Simulated decadal variability compares well with observed O2 changes in the North Atlantic, suggesting that the model captures key mechanisms of late 20th century O2 variability, but the model appears to underestimate variability in the North Pacific.

Our results suggest that large interannual to decadal variations and limited data availability make the detection of human-induced O2 changes currently challenging.

The concentration of dissolved oxygen in the thermocline and the deep ocean is a particularly sensitive indicator of change in ocean transport and biology [Joos et al., 2003]. Less than a percent of the combined atmosphere and ocean O2 inventory is found in the ocean. The O2 concentration in the ocean interior reflects the balance between O2 supply from the surface through physical transport and O2 consumption by respiration of organic material.

Our modeling study suggests that over recent decades internal natural variability tends to mask simulated century-scale trends in dissolved oxygen from anthropogenic forcing in the North Atlantic and Pacific. Observed changes in oxygen are similar or even smaller in magnitude than the spread of the ensemble simulation. The observed decreasing trend in dissolved oxygen in the Indian Ocean thermocline and the boundary region between the subtropical and subpolar gyres in the North Pacific has reversed in recent years [McDonagh et al., 2005; Mecking et al., 2008], implicitly supporting this conclusion.

The presence of large-scale propagating O2 anomalies, linked with major climate modes, complicates the detection of long-term trends in oceanic O2 associated with anthropogenic climate change. In particular, we find a statistically significant link between O2 and the dominant climate modes (NAO and PDO) in the North Atlantic and North Pacific surface and subsurface waters, which are causing more than 50% of the total internal variability of O2 in these regions.

To date, the ability to detect and interpret observed changes is still limited by lack of data. Additional biogeo-chemical data from time series and profiling floats, such as the Argo array (http://www.argo.ucsd.edu) are needed to improve the detection of ocean oxygen and carbon system changes and our understanding of climate change.

The Real Issue is Ocean Dead Zones, Both Natural and Man-made

 

Since 1994, he and the World Resources Institute (report here) in Washington,D.C., have identified and mapped 479 dead zones around the world. That’s more than nine times as many as scientists knew about 50 years ago.

What triggers the loss of oxygen in ocean water is the explosive growth of sea life fueled by the release of too many nutrients. As they grow, these crowds can simply use up too much of the available oxygen.

Many nutrients entering the water — such as nitrogen and phosphorus — come from meeting the daily needs of some seven billion people around the world, Diaz says. Crop fertilizers, manure, sewage and exhaust spewed by cars and power plants all end up in waterways that flow into the ocean. Each can contribute to the creation of dead zones.

Ordinarily, when bacteria steal oxygen from one patch of water, more will arrive as waves and ocean currents bring new water in. Waves also can grab oxygen from the atmosphere.

Dead zones develop when this ocean mixing stops.

Rivers running into the sea dump freshwater into the salty ocean. The sun heats up the freshwater on the sea surface. This water is lighter than cold saltier water, so it floats atop it. When there are not enough storms (including hurricanes) and strong ocean currents to churn the water, the cold water can get trapped below the fresh water for long periods.

Dead zones are seasonal events. They typically last for weeks or months. Then they’ll disappear as the weather changes and ocean mixing resumes.

Solutions are Available and do not Involve CO2 Emissions

Helping dead zones recover

The Black Sea is bordered by Europe and Asia. Dead zones used to develop here that covered an area as large as Switzerland. Fertilizers running off of vast agricultural fields and animal feedlots in the former Soviet Union were a primary cause. Then, in 1989, parts of the Soviet Union began revolting. Two years later, this massive nation broke apart into 15 separate countries.

The political instability hurt farm activity. In short order, use of nitrogen and phosphorus fertilizers by area farmers declined. Almost at once, the size of the Black Sea’s dead zone shrunk dramatically. Now if a dead zone forms there it’s small, Rabalais says. Some years there is none.

Chesapeake Bay, the United State’s largest estuary, has its own dead zone. And the area affected has expanded over the past 50 years due to pollution. But since the 1980s, farmers, landowners and government agencies have worked to reduce the nutrients flowing into the bay.

Farmers now plant cover crops, such as oats or barley, that use up fertilizer that once washed away into rivers. Growers have also established land buffers to absorb nutrient runoff and to keep animal waste out of streams. People have even started to use laundry detergents made without phosphorus.

In 2011, scientists reported that these efforts had achieved some success in shrinking the size of the bay’s late-summer dead zones.

The World Resources Institute lists 55 dead zones as improving. “The bottom line is if we take a look at what is causing a dead zone and fix it, then the dead zone goes away,” says Diaz. “It’s not something that has to be permanent.”

Summary

Alarmists/activists are again confusing the public with their simplistic solution for a complex situation. And actual remedies are available, just not the agenda preferred by climatists.


Waste Management Saves the Ocean

 

Ocean Climate Ripples

Posted on by Ron Clutz

Dr. Arnd Bernaerts is again active with edifying articles on how humans impact upon the oceans and thereby the climate. His recent post is Global Cooling 1940 – 1975 explained for climate change experts

I and others first approach Dr. Bernaerts’ theory relating naval warfare to climate change with a properly skeptical observation. The ocean is so vast, covering 71% of our planet’s surface and up to 11,000 meters deep, with such a storage of solar energy that it counteracts all forcings including human ones.

As an oceanographer, Bernaerts is well aware of that generalization, having named his website Oceans Govern Climate. But his understanding is much more particular and more clear to me in these recent presentations. His information is encyclopedic and his grasp of the details can be intimidating, but I think I get his main point.

When there is intense naval warfare concentrated in a small, shallow basin like the North Sea, the disturbance of the water structure and circulation is profound. The atmosphere responds, resulting in significant regional climate effects. Nearby basins and continents are impacted and eventually it ripples out across the globe.

The North Atlantic example is explained by Bernaerts Cooling of North Sea – 1939 (2_16) Some excerpts below.

Follow the Water

Water, among all solids and liquids, has the highest heat capacity except for liquid ammonia. If water within a water body remained stationary and did not move (which is what it does abundantly and often forcefully for a number of reasons), the uppermost water surface layer would, to a very high percentage, almost stop the transfer of any heat from a water body to the atmosphere.

However, temperature and salt are the biggest internal dynamic factors and they make the water move permanently. How much the ocean can transfer heat to the surface depends on how warm the surface water is relative to atmospheric air. Of no lesser importance is the question, as to how quickly and by what quantities cooled-down surface water is replaced by warmer water from sub-surface level. Wind, cyclones and hurricanes are atmospheric factors that quickly expose new water masses at the sea surface. Another ‘effective’ way to replace surface water is to stir the water body itself. Naval activities are doing just this.

War in the North Sea

Since the day the Second World War had started naval activities moved and turned the water in the North Sea at surface and lower levels at 5, 10, 20 or 30 metres or deeper on a scale that was possibly dozens of times higher than any comparable other external activity over a similar time period before. Presumably only World War One could be named in comparison.

The combatants arrived on the scene when the volume of heat from the sun had reached its annual peak. Impacts on temperatures and icing are listed in the last section: ‘Events’ (see below). The following circumstantial evidences help conclude with a high degree of certainty that the North Sea contributed to the arctic war winter of1939/40.

Climate Change in Response

On the basis of sea surface temperature record at Helgoland Station and subsequent air temperature, developments provide strong indication that the evaporation rate was high. This is confirmed by the following impacts observed:

More wind: As the rate of evaporation over the North Sea has not been measured and recorded, it seems there is little chance to prove that more vapour moved upwards during autumn 1939 than usual. It can be proved that the direction of the inflow of wind had changed from the usually most prevailing SW winds, to winds from the N to E, predominantly from the East. At Kew Observatory (London) general wind direction recorded was north-easterly only three times during 155 winter years; i.e. in 1814, 1841 and 1940[6]. This continental wind could have significantly contributed to the following phenomena of 1939: ‘The Western Front rain’.

More rain: One of the most immediate indicators of evaporation is the excessive rain in an area stretching from Southern England to Saxony, Silesia and Switzerland. Southern Baltic Sea together with Poland and Northern Germany were clearly separated from the generally wet weather conditions only three to four hundred kilometres further south. A demonstration of the dominant weather situation occurred in late October, when a rain section (supplied from Libya) south of the line Middle Germany, Hungary and Romania was completely separated from the rain section at Hamburg – Southern Baltic[7].

More cooling: Further, cooling observed from December 1939 onward can be linked to war activities in two ways. The most immediate effect, as has been explained (above), is the direct result from any excessive evaporation process. The second (at least for the establishment of global conditions in the first war winter) is the deprivation of the Northern atmosphere of its usual amount of water masses, circulating the globe as humidity.

Rippling Effects in Northern Europe and Beyond

Next to the Atlantic Gulf Current, the North Sea (Baltic Sea is discussed in the next chapter) plays a key role in determining the winter weather conditions in Northern Europe. The reason is simple. As long as these seas are warm, they help sustain the supremacy of maritime weather conditions. If their heat capacity turns negative, their feature turns ‘continental’, giving high air pressure bodies an easy opportunity to reign, i.e. to come with cold and dry air. Once that happens, access of warm Atlantic air is severely hampered or even prevented from moving eastwards freely.

The less moist air is circulating the globe south of the Arctic, the more easily cold polar air can travel south. A good piece of evidence is the record lack of rain in the USA from October – December 1939 followed by a colder than average January 1940, a long period of low water temperatures in the North Sea from October-March (see above) and the ‘sudden’ fall of air temperatures to record low in Northern Europe.

The graph above suggests that naval warfare is linked to rapid cooling. The climate system responds with negative feed backs to restore equilibrium. Following WWI, limited to the North Atlantic, the system overshot and the momentum continued upward into the 1930s. Following WWII, with both Pacific and Atlantic theaters, the climate feed backs show several peaks trying to offset the cooling, but the downward trend persisted until about 1975.

Summary

The Oceans Govern Climate. Man influences the ocean governor by means of an expanding fleet of motorized propeller-driven ships. Naval warfare in the two World Wars provide the most dramatic examples of the climate effects.

Neither I nor Dr. Bernaerts claim that shipping and naval activity are the only factors driving climate fluctuations. But it is disturbing that so much attention and money is spent on a bit player CO2, when a much more plausible human influence on climate is ignored and not investigated.

AMO: Atlantic Climate Pulse

Posted on by Ron Clutz

I was inspired by David Dilley’s weather forecasting based upon Atlantic water pulsing into the Arctic Ocean (see post: Global Weather Oscillations). So I went looking for that signal in the AMO dataset, our best long-term measure of sea surface temperature variations in the North Atlantic.

ATLANTIC MULTI-DECADAL OSCILLATION (AMO)

For this purpose, I downloaded the AMO Index from Kaplan SST v.2, the unaltered and untrended dataset. By definition, the data are monthly average SSTs interpolated to a 5×5 grid over the North Atlantic basically 0 to 70N.

For an overview the graph below presents a comparison between Annual, March and September averages from 1856 to 2016 inclusive.

amo-march-sept

We see about 4°C difference between the cold month of March, and warm September. The overall trend is slightly positive at 0.27°C per century, about 10% higher in September and 10% lower in March. It is also clear that monthly patterns resemble closely the annual pattern, so it is reasonable to look more closely into Annual variability.

The details of the Annual fluctuations in AMO reveal the pulse pattern suggested by Dilley.

amo-pulses-2

We note firstly the classic pattern of temperature cycles seen in all datasets featuring quality-controlled unadjusted data. The low in 1913, high in 1944, low in 1975, and high in 1998. Also evident are the matching El Nino years 1998, 2009 and 2016, indicating that what happens in the Pacific does not stay in the Pacific.

Most interesting are the periodic peaking of AMO in the 8 to 10 year time frame. The arrows indicate the peaks, which as Dilley describes produce a greater influx of warm Atlantic water under the Arctic ice. And as we know from historical records and naval ice charts, Arctic ice extents were indeed low in the 1930s, high in the 1970s, low in the 1990s and on a plateau presently.

Conclusion

I am intrigued but do not yet subscribe to the Lunarsolar explanation for these pulses, but the AMO index does provide impressive indication of the North Atlantic role as a climate pacemaker. Oceans make up 71% of the planet surface, so SSTs directly drive global mean temperatures (GMT). But beyond the math, Atlantic pulses set up oscillations in the Arctic that impact the world.

In the background is a large scale actor, the Atlantic Meridional Overturning Circulation (AMOC) which is the Atlantic part of the global “conveyor belt” moving warm water from the equatorial oceans to the poles and back again.  For more on this deep circulation pattern see Climate Pacemaker: The AMOC

Oceans Make 2015 & 2016 Climate

Posted on by Ron Clutz

 

Ocean temperature measurements come from a global array of 3,500 Argo floats and other ocean sensors. Credits: Argo Program, Germany/Ifremer

We are seeing lots of claims about the temperature records for 2016 and 2015 proving dangerous man made warming.  At least one senator stated that in a confirmation hearing.  Now that HadSST3 data is complete for last year, let’s see how obvious is the ocean’s governing of global average temperatures.

The best context for understanding these two years 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 these years.

HadSST is generally regarded as the best of the global SST data sets, and so the temperature story here comes from that source, the latest version being HadSST3.

The chart below shows the last two years of SST monthly anomalies as reported in HadSST3.

hadsst3-2015-2016all

Note that higher temps in 2015 and 2016 are first of all due to a sharp rise in Tropical SST, beginning in March 2015, peaking in January 2016, and steadily declining back to its beginning level. Secondly, the Northern Hemisphere added two bumps on the shoulders of Tropical warming, with peaks in August of each year. Also, note that the global release of heat was not dramatic, due to the Southern Hemisphere offsetting the Northern one.

Finally, the oceans are entering 2017 at the same temperature level as 2015, only now with downward momentum.

Much ado will be made of this warming, including claims of human causation, despite the obvious oceanic origin. However, it is unreasonable to claim CO2 functions as a global warming agent, yet the two hemispheres respond so differently.  Moreover, CO2 warming theory expects greater warming in the higher latitudes, while this event was driven by heating in the Tropics, contradicting alarmist warming theory.

Solar energy accumulates massively in the ocean and is variably released during circulation events.

 

The Ocean Climate Spin Zone

Posted on by Ron Clutz

ocean_gyres_big

This image shows the five major ocean gyres. It shows that gyres rotate in a clockwise direction in the Northern hemisphere and a counter-clockwise direction in the Southern hemisphere. The black square shows the approximate location of the Great Pacific Garbage Patch and the red circle shows the position of the Beaufort gyre in the Arctic Ocean.

Professional hydrologist Rob Ellison has for years been thinking and writing to connect the dots between the sun, ocean and climate. Recently he wrote this post at his excellent blog Terra et Aqua, An Earnest Discovery of Climate Causality (link in red)

Below I provide some excerpts from his discussion about an ocean mechanism which would be much better understood, were it not for the CO2 obsession sucking up most of the research funding.

Overview

It is hypothesized that upwelling in the Pacific Ocean is modulated by solar activity over periods of decades to millennia – with profound impacts on communities and ecosystems globally. The great resonant systems of the Pacific respond at variable periods – the tempo increased last century for instance – of La Niña and El Niño alternation. . .The mechanism proposed is a spinning up of the Pacific gyres as a result of colder and denser polar air. Low solar activity spins up the gyres producing more frequent La Niña (more equatorial upwelling) – and vice versa.

Pacific Oscillations Global Impact

The Pacific has a globally influential role in climate variability at scales of months to millennia. The variability in atmospheric temperature, rainfall and biology has its origin in the volume of cold water rising off California and in the equatorial Pacific. It is an ever changing anomaly.

The principle of atmospheric heating and cooling by ENSO is very simple. Cold, nutrient rich currents cascade through the deep oceans over a millennia or more. These turbulent currents don’t generally emerge through a sun warmed surface layer. By far the most significant deep ocean upwelling is in the eastern and central Pacific. Cold water in contact with the atmosphere absorbs heat and warms as the atmosphere cools. At times there is less upwelling and warm water spreads eastward across the Pacific – warming the atmosphere. It is simple enough to see in temperature data.

I have a preference for near global coverage and depth integrated satellite temperature records – it doesn’t miss energy in latent heat at the surface for one thing. 21st century instrumentation is much to be preferred going forward. Over the past century the 20 to 30 year influence of the Pacific Decadal Oscillation (PDO) anomaly can be seen in the surface records. Warming to the mid 1940’s, cooling to 1976, warming to 1998 and little change since. The PDO and ENSO are, moreover, in lockstep. A cooler PDO anomaly and more frequent and intense La Niña – and vice versa.

Pacific Gyres Spinning Up Climate Change

The atmospheric/ocean system of triggers and feedbacks varies – usually abruptly with triggers. The trigger for more upwelling I can only imagine is the great ocean gyres. Ocean gyres spin up on the surface through winds and planetary rotation. Pressure systems shift polar winds and storms into lower latitudes. High polar atmospheric pressures spin up the gyres pushing cold polar water into the Californian and Peruvian currents. Roiling cold water upwelling sets up wind and current feedback across the Pacific.

More polar cold water at the surface facilitates upwelling in critical regions.  Trade winds spin up as a feedback and piles warm water against Australia and Indonesia.  Sometimes the winds falter and warm water flows back eastward suppressing cold upwelling.  The whole is a complex and dynamic system triggered by changes in atmospheric pressure zones in the north and south Pacific.  Great movements of atmospheric mass driven by a marginal change in solar activity.  A large reaction from a small jolt as expected with technically chaotic systems.

Tessa Vance and colleagues from the Antarctic Climate and Ecosystems CRC found a proxy of eastern Pacific upwelling in an ice core at the Law Dome Antarctica.  A higher salt content – from polar westerlies – is a proxy for solar activity.  But also results in changes in the great Pacific gyres and the intensity of upwelling.   More upwelling brings rain and cyclones to Indonesia and northern and eastern Australia, drought in the United States of and South America, cooler global temperatures and biological abundance.   Less in El Niña conditions and we – in Australia – get drought.   The absolute volume of rainfall is roughly constant but where it falls on the planet changes.

The record captures in high resolution the 20 to 30 year Pacific beat, the change in the ENSO tempo last century and has at least a resemblance to the solar signal over a 1000 years.  But even with a millennial high El Niño anomaly last century – conditions have been far more extreme at other times in the past 12,000 years.

Conclusion

Will there be more La Niña over the next centuries? Can we expect more El Niño in a thousand years?  Might we see great herds return to the Sahel?  The future remains unpredictable.   Still – a return to the mean scenario does suggest better odds on a cooler sun and a little more upwelling in the Pacific Ocean – a cooling influence on the atmosphere and the inevitable regional variabilities in rainfall.

Oceans Make Climate is a major theme at this blog, since I fortunately made the acquaintance of Dr. Arnd Bernaerts.  Rob Ellison adds another important dimension with his consideration of the gyres.

Footnote:

Recently I noticed how sea surface temperatures drove the 2015-2016 global warming, as shown in the HadSST3 record:

Note that higher temps in 2015 and 2016 are first of all due to a sharp rise in Tropical SST, beginning in March 2015, peaking in January 2016, and steadily declining back to its beginning level. Secondly, the Northern Hemisphere added two bumps on the shoulders of Tropical warming, with peaks in August of each year. Finally, note that the global release of heat was not dramatic, due to the Southern Hemisphere offsetting the Northern one.

Much ado will be made of this warming, including claims of human causation, despite the obvious oceanic origin. Further, it is curious that CO2 functions as a warming agent so unevenly around the world, and that the Tropics drove this event, contradicting CO2 warming theory.

Anatomy of the Hottest Years Ever

 

Anatomy of the Hottest Years Ever

Posted on by Ron Clutz

 

Ocean temperature measurements come from a global array of 3,500 Argo floats and other ocean sensors. Credits: Argo Program, Germany/Ifremer

With the year end, media climate attack dogs are going after the Trump administration, throwing whatever they can (hoping for anything to stick). One thing they will surely trumpet is the temperature records for 2016 and 2015 as proof of dangerous man made warming.

Now the best context for understanding these two years 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 these years.

HadSST is generally regarded as the best of the global SST data sets, and so the temperature story here comes from that source, the latest version being HadSST3.

The chart below shows the last two years of SST monthly anomalies as reported in HadSST3.

hadsst3-2015-2016

Note that higher temps in 2015 and 2016 are first of all due to a sharp rise in Tropical SST, beginning in March 2015, peaking in January 2016, and steadily declining back to its beginning level. Secondly, the Northern Hemisphere added two bumps on the shoulders of Tropical warming, with peaks in August of each year. Finally, note that the global release of heat was not dramatic, due to the Southern Hemisphere offsetting the Northern one.

Much ado will be made of this warming, including claims of human causation, despite the obvious oceanic origin. Further, it is curious that CO2 functions as a warming agent so unevenly around the world, and that the Tropics drove this event, contradicting global warming theory.

Solar energy accumulates massively in the ocean and is variably released during circulation events.

 

Tornados: Blame them on La Niña

Posted on by Ron Clutz

A tornado brews near El Reno, Okla., May 2013. A new study links the frequency of tornadoes and hailstorms in parts of the southern United States to ENSO, a cyclic temperature pattern in the Pacific Ocean. Credit: John Allen

Reported in Science Daily Frequency of tornadoes, hail linked to El Niño, La Niña

“We can forecast how active the spring tornado season will be based on the state of El Niño or La Niña in December or even earlier,” said lead author John Allen, a postdoctoral research scientist at the International Research Institute for Climate and Society (IRI).

Allen and his coauthors show that moderately strong La Niña events lead to more tornadoes and hail storms over portions of Oklahoma, Texas, Kansas and other parts of the southern United States. El Niño events act in the opposite manner, suppressing both types of storms in this area.

While the information can’t pinpoint when and where storms will wreak havoc, it will nevertheless be useful for governments and insurance companies to prepare for the coming season, Allen said.

The Tornado statistics are available from the Storm Prediction Center (here).

El Niño was in effect for 2015 and most of 2016.  2015 had 36 deaths, all but 10 of them between Dec. 23 and 26. This year there have been 17 deaths recorded. An average year is 80 tornado deaths.

TOP 5 GREATEST U.S. ANNUAL TORNADO DEATH TOLLS

RANK YEAR DEATHS
1) 1925 794
2) 2011 553
3) 1936 552
4) 1917 551
5) 1927 540

In 2011–a La Niña year– tornadoes killed more than 550 people, higher than in the previous 10 years combined. Hail storms and tornadoes cause an average estimated $1.6 billion in insured losses each year in the United States, according to the insurer Munich RE. Powerful, isolated events such as the 2011 Joplin, Missouri, tornado can smash that average. That storm alone caused several billion dollars in damage and killed 158 people.

Image: La Niña is characterized by unusually cold ocean temperatures in the central equatorial Pacific. The colder than normal water is depicted in this image in blue. During a La Niña stronger than normal trade winds bring cold water up to the surface of the ocean. Credit: NASA

Image: La Niña is characterized by unusually cold ocean temperatures in the central equatorial Pacific. The colder than normal water is depicted in this image in blue. During a La Niña stronger than normal trade winds bring cold water up to the surface of the ocean. Credit: NASA

Past studies that have relied on eyewitness records alone have had limited success, said Allen. “For example, previous work has shown a clear linkage between ENSO and winter activity, but spring–the season when most of tornadoes occur in the southern U.S.–remained an enigma until now,” Allen said.

To get around these challenges, the Columbia University team created indices derived from environmental conditions such as wind shear, temperature and moisture. Each is a key ingredient in severe storm formation, and each is influenced by ENSO. The scientists then verified the indices using available observational records.

Summary

If La Niña strengthens beyond its present near-neutral condition, look for more killer tornados in the SE United States.  But it is not the fault of CO2 or fossil fuels.

Footnote December 4

I want to be as careful as the authors not to overstate the certainty of their findings. (h/t comment by Les Johnson).  Tornados are mesoscale events with multiple contributing factors.  Researchers have concluded that ENSO sets environmental conditions that favor or disfavor tornado formation, i.e. increase or decrease the probabilities.

Michon Scott provides a more detailed description of the mechanism entitled El Niño and La Niña affect spring tornadoes and hailstorms at Climate.gov (here).

In these maps, purple indicates higher storm event frequency, and brown indicates lower storm event frequency. Specifics vary, but in general, springtime tornadoes and hailstorms are less frequent in the southern central United States during El Niño, and more frequent during La Niña.

The research showed that ENSO affects tornado and hailstorm frequency by influencing the position of the jet stream over North America. El Niño weakens the surface winds that carry warm, most air from the Gulf of Mexico over Texas and neighboring states. La Niña, in contrast, concentrates hot, humid air over the region. The heat and humidity over the southern Plains states sets up a strong north-south temperature gradient, which in turn favors storm formation.

El Niño/La Niña conditions often persist from winter into spring, the researchers found, so the ENSO state seen in December, January, and February can be used to predict tornado and hailstorm frequency for March, April, and May.

Tornado season and hail season don’t have set beginnings and endings. In general, tornado season peaks in Gulf Coast states in the spring, in the southern Plains in May and June, and in upper Midwest in June and July. . . But tornadoes can strike at any time of year. Severe hailstorms often strike between May and July, but can also occur at any time of year.

El Nino’s Hottest Year

Posted on by Ron Clutz

With just 2 months to go, it could well be that 2016 replaces 1998 as the “hottest year ever.” With the Pacific Blob only now dissipated, and La Nina delaying her appearance, it is becoming likely that the inevitable cooling will come only next year. That may result in an annual GMT surpassing 1998 in the satellite record.

Fossil fuel activists and consensus climate scientists will claim this proves CO2 is causing global warming, but knowledgeable people know they are once again dissing the Ocean in order to push their agenda.

Actual data, rather than computer models, show that ocean oscillations, not CO2 have produced the bulk of warming in the temperature record. ENSO (El Nino Southern Oscillation) produces sea surface temperature anomalies (SSTa) resulting in most of the variability in global averages.

Climatists will blame the rise on so-called “greenhouse gases” asserting several unproven notions:

  • CO2 induces atmospheric warming which raises SSTs;
  • Higher SSTs increase evaporation and clouds that trap LW radiation, thereby further raising surface temperatures;
  • ENSO warming and cooling cycles cancel out each other leaving CO2 as the sole warming agent.

As the final results for 2016 come in, expect the media to bombard the masses with declarations along these lines. The purpose of this post is inoculation (like a flu shot) to protect against the feverish reporting ahead.

How El Nino Affects Surface Temperatures

Roy Spencer and William Braswell looked at the data in their 2014 published article (here)
The Role of ENSO in Global Ocean Temperature Changes during 1955-2011

Roy Spencer May 13, 2014 on WUWT (here):

Based on global area-average ocean signatures, the observational evidence regarding the *global oceanic* signature of El Nino is this:

1) El Nino involves a decrease in the overturning in the 0-200 m layer, which leads to warming of the upper 100 m and cooling of the 100-200m layer. We calculate this is 2/3 of the source of surface warming.

2)El Nino surface warmth is partly driven by a decrease in cloud cover letting more sunlight in…This is 1/3 of the surface warming, and it also appears to contribute to longer-term deep ocean warming if there are stronger El Ninos and weaker La Ninas than average..

In the same thread Bob Tisdale comments:

ENSO impacts when and where sunlight reaches the surface of the oceans and penetrates into the oceans. . . ENSO also impacts how energy is released from the oceans to the atmosphere which further impacts the energy balance.

Keep in mind that the majority (about 90%) of the heat released from the ocean is through evaporation. During an El Nino, more of the surface of the tropical Pacific is covered with warm water, which yields more evaporation. And the opposite holds true during a La Nina.

Ocean Heat Also Rises

When there are super-El Nino years such as 1998 and 2016, climatists insist on attributing warming to fossil fuel emissions. Obsessed with CO2 and radiative energy flows, they are unable to see and affirm this oceanic climate driver. An extended discussion at Climate Etc. (here) included a series of comments by Kristian that provide a synopsis of El Nino’s role in global warming.

This is what the data consistently shows: surface temps up (or down) > tropospheric temps up (or down) > OLR at ToA up (or down).

This is how the heat from the sun actually flows through the earth system. Surface warms first, then the troposphere, then, as a consequence of this, the radiative output to space increases. There is NO observational evidence anywhere for the opposite process to occur: OLR at ToA down >tropospheric temps up > surface temps up.

Radiatively active gases in the atmosphere do not enable it to WARM. It would’ve warmed with or without them, simply by being directly convectively coupled with the solar-heated surface. This connection is never broken as long as there is air present, a gravity field and sunshine heating the surface.

Radiatively active gases, however, DO enable the atmosphere to adequately COOL to space. Because this can only be done through radiation.

So an atmosphere without radiatively active gases would still WARM from the surface up, but wouldn’t be able to adequately COOL to space.

It’s not the so-called ‘GHGs’ that trap the surface heat. It’s the 99.5% of the atmosphere NOT being significantly radiatively active at ‘earthly’ temperatures that would do that. Because this part can STILL be warmed conductively, convectively and latently, but it can’t to any real extent radiate it away again.

ENSO Discharges and Recharges Ocean Heat Content

Image: La Niña is characterized by unusually cold ocean temperatures in the central equatorial Pacific. The colder than normal water is depicted in this image in blue. During a La Niña stronger than normal trade winds bring cold water up to the surface of the ocean. Credit: NASA

Image: La Niña is characterized by unusually cold ocean temperatures in the central equatorial Pacific. The colder than normal water is depicted in this image in blue. During a La Niña stronger than normal trade winds bring cold water up to the surface of the ocean. Credit: NASA

As a rule of thumb, El Niños cause global warming but drain global heat (actually, ‘energy’) content. El Niño: global surface/troposphere temps UP, global internal energy DOWN.

Why the distinction? Because most of the stored-up (solar) energy of the earth system is to be found at depth in the oceans, that is, AWAY FROM the surface. What an El Niño does is to pull a significant amount of this energy up from its hiding place in the deep and instead spreads it out across a huge area on the surface, raising its temperature in the process, laying the energy bare, so to speak, to be lost from the ocean to the atmosphere (and ultimately to space) through evaporation (deep/moist convection) and conduction. Radiation also occurs but to a much lesser degree.

So, the depths of the ocean – well, basically of the IPWP (the Indo-Pacific Warm Pool) – is drained of energy during an El Niño, it ‘cools’, while the surface in the tropics of the Central and East Pacific (where the NINO3.4 region is located), warms up immensely, the SST here shoots up.

Following this significant tropical Central and East Pacific surface warming, the troposphere above it warms from the vastly increased transfer and freeing of latent heat. The warming of the tropical Pacific also affects the atmospheric circulation over the rest of the tropics through so-called ‘atmospheric bridges’, indirectly inducing a lagged warming also in the Atlantic and Indian ocean basins.

From the tropics/subtropics, part of the El Niño released ocean heat is then transported (mostly via the atmosphere) out to the extratropics, eventually ending up in the polar regions (well, in reality it mostly ends up in the Arctic, not in the Antarctic, the reason being a profound difference between northern and southern hemisphere extratropical circulation.)

The massive amount of energy released onto the world during an El Niño event is neither generated by nor absorbed during the event itself. The energy of course originally came from the sun and it was stored up during the La Niña normally preceding the El Niño.

It’s the La Niñas (and often also during neutral ENSO conditions, much more resembling the cool events than the warm events) that builds ‘global heat content’. They soak up the solar energy and store it at depth. The El Niños subsequently release it again.

Global Warming Since 1970 Due to Major El Ninos

Since 1970 we have seen four ENSO sequences where a strong and solitary El Niño is surrounded by (preceded AND succeeded by) La Niña-events. In each sequence, the storing up of energy during the often extended/prolonged La Niña periods has far outdone the energy depletion during the strong, but mostly short El Niño-events.

1. During the period 1970-76 only one year saw an El Niño (1972/73). The rest of the years, 1970-72 and 1973-76, were mostly La Niña-dominated.

2. During the period 1983-89, two years back-to-back saw El Niño-conditions (1986-88). The years 1983-86 saw either cold neutral or La Niña-conditions and the year 1988/89 saw one of the strongest La Niñas of modern history.

3. During the period 1995-2001 only one year saw an El Niño (1997/98). The rest of the years, 1995-97 and 1998-2001, were mostly La Niña-dominated.

4. During the period 2007-14 only one year saw an El Niño (2009/10). The rest of the years, 2007-09 and 2010-14, were mostly La Niña-dominated.

5. Beginning in 2015 another major El Nino event occurred, peaking mid 2016.  From past experience, we expect a La Nina to follow in coming months.  Over the next few years it will be evident whether or not a new step level results from this event.

The periods in between these sequences of clustered distinct cool and warm ENSO events, 1976-83, 1989-95 and 2001-07, were all neutral to warmish, with much smaller variations from the mean state and prominently without any clear extended cold events, lacking the strength to create a global signal.

El Nino temperatures correlate well with satellite global temperatures

temperature_el_nino_satellite-b

The oceans are not some passive reservoir where the solar energy just comes and goes as it wants and always in complete balance. No, they are quite dynamic and the absorbed energy is held back or is released, according to their own internal processes. If the climatic conditions (the coupled ocean/atmosphere system) in the Pacific basin are such that they promote net storage of solar energy over several decades, well, then that is what will happen. Quite naturally. That doesn’t mean that these conditions will prevail forever.

We KNOW that large-scale and fairly abrupt climate shifts occur in the (pan-)Pacific basin at certain intervals. In fact, there has been no additional global warming OUTSIDE of these sudden hikes, from 1970 till today. That means, the ENTIRE modern global warming seen since 1970 is contained within the steps up during the Great Pacific Climate Shift of the late 70s and the two following ones in 1988/89 and 1998/99.

The ENTIRE modern global warming is found in these three sudden hikes alone, all occurring within the time-span of less than a year.

El Nino Spreads Warming From Sea to Sea

How did global warming progress from 1975/76 to 2001/02? Follow the data. No preconceived ideas about mechanisms.

First of all, there is no question that there is a definite East Pacific signal plastered all over the global temperature series. Compare with NINO3.4:

nino-kristian-1

In fact, global temperatures tend to lag NINO3.4 SSTa by several months. And everyone knows that this particular correlation also speaks causation. Not just from the consistent and tight lead-lag relation, but from the thoroughly explicated oceanic/atmospheric mechanisms by which we know the large-scale and integrated ENSO process creates global warming and cooling. I’m talking here about the major swings up and down that we see all along from 1970 till today.

What went on in 1978/79, in 1988 and in 1998? What was so special about these three short time segments? Why is the ENTIRE ‘modern global warming’ contained within them?

Bob Tisdale:
Those upward shifts are the long-term responses to the discharge phases of ENSO that occurs during strong El Niños. As part of the discharge phase of ENSO, the El Niño takes warm water from below the surface of the western tropical Pacific and places it on the surface (warm water that was created by the increased sunlight during the prior recharging La Niña). The discharged warm water floods into the East Pacific, where it temporarily raises sea surface temperatures during the El Niño, but causes little long-term trend there.

And at the end of the El Niño, the warm water is redistributed by the renewed trade winds, ocean currents and the downwelling Rossby wave into the West Pacific, Indian Ocean and eventually the South Atlantic. The East Pacific represents about 33% of the surface of the global oceans, and the South Atlantic-Indian-West Pacific covers another 52%. That leaves the North Atlantic, which has another mode of natural variability called the Atlantic Multidecadal Oscillation. The Atlantic Multidecadal Oscillation, according to NOAA, can contribute to or suppress global warming. And so far, the only global surface warming we’ve seen was in the South Atlantic-Indian-West Pacific subset and that warming was caused by discharge of sunlight-created warm water released from below the surface of the West Pacific Warm Pool during El Niño events.

For data on ocean-air heat exchanges see: Empirical Evidence: Oceans Make Climate

blame-it-on-enso