Ocean circulation is key to understanding uncertainties in climate change predictions

A portion of the Atlantic meridional overturning circulation [image credit: R. Curry, Woods Hole Oceanographic Institution @ Wikipedia]

Widely differing climate models are supposed to be a reliable guide to the future? Clearly not. Here the uncertainty gets investigated, and pinned on a phenomenon that was recently claimed by Mann et al not to exist. Of course all these models make the assumption that carbon dioxide at a tiny 0.04% of the atmosphere is a key variable of concern, despite all the other variability in the climate system that they have to wrestle with.
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Thirty state-of-the-art IPCC-climate models predict dramatically different climates for the Northern Hemisphere, especially Europe, says Phys.org.

An analysis of the range of responses now reveals that the differences are mostly down to the individual model’s simulations of changes to the North Atlantic ocean currents and not only—as normally assumed—atmospheric changes.

The work, by Katinka Bellomo, National Research Council of Italy, Institute of Atmospheric Sciences and Climate, and colleagues is published today in Nature Communications and is part of the European science collaboration, TiPES, coordinated by the University of Copenhagen.

All climate models vary in the details. Variables such as atmospheric pressure, cloud cover, temperature gradients, sea surface temperatures, and many more are tuned to interact slightly differently for every model. This means that the predictions of the many models also vary.

Aquatic fungus creates a fast track for carbon dioxide, say researchers

The ocean carbon cycle [credit: IAEA]

Proving once again how massively important carbon dioxide is to nature, via photosynthesis.
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Tiny algae in Earth’s oceans and lakes take in sunlight and carbon dioxide and turn them into sugars that sustain the rest of the aquatic food web, gobbling up about as much carbon as all the world’s trees and plants combined, says Phys.org.

New research shows a crucial piece has been missing from the conventional explanation for what happens between this first “fixing” of CO2 into phytoplankton and its eventual release to the atmosphere or descent to depths where it no longer contributes to global warming. [Talkshop comment – evidence-free assertion.]

The missing piece? Fungus.

A 50,000-year history of current flow yields new climate clues

Credit: NASA – GISS

They refer here to the same AMOC that was recently claimed by Mann et al to be of no significance, or even not to exist at all. But empirical evidence has its uses.
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From 50,000 to 15,000 years ago, during the last ice age, Earth’s climate wobbled between cooler and warmer periods punctuated by occasional, dramatic ice-melting events, says Phys.org.

Previous research has suggested that these oscillations were likely influenced by changes in the Atlantic Meridional Overturning Circulation (AMOC), a pattern of currents that carry warm, tropical water to the North Atlantic, where it cools, sinks, and flows back south. However, the precise role played by the AMOC in ancient climate fluctuations has been unclear.

Now Toucanne et al. have reconstructed the historical flow of a key current in the upper part (the northward flow) of the AMOC, the Glacial Eastern Boundary Current (GEBC), shedding new light on how the AMOC can drive sudden changes in climate.

The GEBC flowed northward along Europe’s continental margin during the last ice age (it persists today as the European Slope Current). To better understand the GEBC’s role in the AMOC, the researchers collected six seafloor sediment cores off the coast of France.

Analysis of grain sizes and isotope levels in the core layers revealed the current’s strength when each layer was deposited, yielding the first high-resolution, 50,000-year historical record of the current.

This new historical record shows that the GEBC flowed faster during warmer intervals of the last ice age but weakened during the coldest periods.

The timing of these changes aligns well with previously established records on AMOC speed and the southward return flow of deep waters to the west.

Comparing the history of the GEBC with other records also shows that major ice-melting events, in which ice age glaciers released huge amounts of freshwater into the Atlantic, correspond with periodic weakening of the current and of the AMOC in general.

Full article here.

Oceans losing oxygen mainly due to global warming, say researchers — but what about CO2?

The ocean carbon cycle [credit: IAEA]

Quoting from the article: ‘The main reason for this is global warming, which leads to a decrease in the solubility of gases and thus also of oxygen.’ Surely the same applies to carbon dioxide (CO2): warmer water causes release of some of it from the oceans into the atmosphere? Diagrams of the Earth’s natural carbon cycle seem conclusive enough.
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The life of almost all animals in the ocean depends on the availability of oxygen, which is dissolved as a gas in seawater, says Phys.org.

However, the ocean has been continuously losing oxygen for several decades. In the last 50 years, the loss of oxygen accumulates globally to about 2% of the total inventory (regionally sometimes significantly more).

The main reason for this is global warming, which leads to a decrease in the solubility of gases and thus also of oxygen, as well as to a slowdown in the ocean circulation and vertical mixing.

Canceling the AMO

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‘So, what exactly is wrong with Mann’s analysis? He relies on global climate models, which are inadequate in simulating the AMO.’
‘Not at all convincing’…

Climate Etc.

by Judith Curry

Conclusion from Michael Mann’s new paper:  “We conclude that there is no compelling evidence for internal multidecadal oscillations in the climate system.”

View original post 5,076 more words

Apparent Atlantic warming cycle likely an artefact of climate forcing, modellers claim

Atlantic Multidecadal Oscillation 1880 to Nov 2018 based on the ERSSTv3b dataset [image credit: Giorgiogp2, bender235 @ Wikipedia]

No prizes for guessing who is behind this one. Climate models ‘prove’ humans are the problem, not nature – heard it before?
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Volcanic eruptions, not natural variability, were the cause of an apparent “Atlantic Multidecadal Oscillation,” a purported cycle of warming thought to have occurred on a timescale of 40 to 60 years during the pre-industrial era, according to a team of climate scientists who looked at a large array of climate modeling experiments. Phys.org reporting.

The result complements the team’s previous finding that what had looked like an “AMO” occurring during the period since industrialization is instead the result of a competition between steady human-caused warming from greenhouse gases and cooling from more time-variable industrial sulphur pollution.

Half a trillion corals: World-first coral count prompts rethink of extinction risks

Coral reef [image credit: Toby Hudson / Wikipedia]

Another climate alarm founders on the rocks of reality. Only recently the World Economic Forum was claiming that corals were at risk of extinction. Now, the data says ‘no’. A co-author of the study noted: “Coral restoration is not the solution to climate change. You would have to grow about 250 million adult corals to increase coral cover on the Great Barrier Reef by just one percent.”
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For the first time, scientists have assessed how many corals there are in the Pacific Ocean—and evaluated their risk of extinction, reports Phys.org.

While the answer to “how many coral species are there?” is ‘Googleable’, until now scientists didn’t know how many individual coral colonies there are in the world.

“In the Pacific, we estimate there are roughly half a trillion corals,” said the study lead author, Dr. Andy Dietzel from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE at JCU).

“This is about the same number of trees in the Amazon, or birds in the world.”

Atlantic’s ‘conveyor belt’ shows no sign of declining, new study shows

A portion of the Atlantic meridional overturning circulation [image credit: R. Curry, Woods Hole Oceanographic Institution @ Wikipedia]

This follows on quite well from our post yesterday about the Beaufort Gyre. Another attempted climate alarm fades away.
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A 30-year reconstruction of the Atlantic meridional overturning circulation shows no decline, reports The Global Warming Policy Forum.

Abstract A decline in Atlantic meridional overturning circulation (AMOC) strength has been observed between 2004 and 2012 by the RAPID-MOCHA-WBTS (RAPID – Meridional Overturning Circulation and Heatflux Array – Western Boundary Time Series, hereafter RAPID array) with this weakened state of the AMOC persisting until 2017.

Climate model and paleo-oceanographic research suggests that the AMOC may have been declining for decades or even centuries before this; however direct observations are sparse prior to 2004, giving only “snapshots” of the overturning circulation. [Talkshop note: continues here].

Record-high Arctic freshwater will flow to Labrador Sea, affecting local and global oceans

Arctic currents [image credit: Brn-Bld @ Wikipedia]

In climate terms any potential Beaufort Gyre effect – due to its ability to reverse its flow direction under certain conditions – is a known unknown, so an interesting one to speculate on.
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Freshwater is accumulating in the Arctic Ocean, says Phys.org.

The Beaufort Sea, which is the largest Arctic Ocean freshwater reservoir, has increased its freshwater content by 40% over the past two decades.

How and where this water will flow into the Atlantic Ocean is important for local and global ocean conditions.

MET Office global temperature prediction falls 0.35C in 5 years.

Back in 2016, the UK MET Office’s median projection to the start of 2021 forecast a global temperature temperature anomaly of 1.4C above their 1850-1900 “Pre-Industrial” baseline. Their recently published five year model projection (rightmost blue blob on graph), shows a 2021 median anomaly 0.35C lower, at 1.05C.

Their HADcruT 4GL temperature time series (data since 2016 added in red on graph) shows a linear trend of +0.09C/semi-decade for the last 50 years. CO2, by far the biggest forcing in their model, is still rising in lockstep with the 50 year temperature trend. What could have caused this remarkable downward step change in their model output?

Why are hundreds of Pacific Islands growing despite rising sea levels?

In the Maldives

Just as the late Nils-Axel Mörner, a lifelong sea levels researcher, explained in an interview about two years ago. Let’s hope the climate miserablists now give up on their ‘drowning islands’ nonsense.
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New research says hundreds of islands in the Pacific are growing in land size, even as climate change-related sea level rises threaten the region, says ABC News Australia.

Scientists at the University of Auckland found atolls in the Pacific nations of Marshall Islands and Kiribati, as well as the Maldives archipelago in the Indian Ocean, have grown up to 8 per cent in size over the past six decades despite sea level rise.

They say their research could help climate-vulnerable nations adapt to global warming in the future.

Hollywood scenarios ruled out in north Atlantic Ocean study

Credit: NASA – GISS

The researchers conclude that “the AMOC states in both the subpolar and subtropical North Atlantic between the 1990s and 2010s are indistinguishably different from each other”. In effect: nothing to see here, put the alarm bells away.
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Ocean vertical structures are changing as a result of global warming, says Phys.org.

Whether these changes are in pace with the ocean circulation is unknown.

Now, an international team of scientists from the South China Sea Institute of Oceanology (SCSIO) of the Chinese Academy of Sciences, China, Georgia Institute of Technology, U.S., and GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany, gave an answer to the question.

According to their study published in Science Advances on Nov. 27, ocean circulation changes and ocean interior property changes may not occur at the same pace as it was previously suggested.

Refutation of Michael Mann’s latest statistical shenanigans

Pacific ocean [image credit: Wikipedia]

In climate propaganda land anything to do with the natural variation that is always going on is bad news, and liable to be maligned or ignored, as we see here. The PDO for example is well known to government agencies like NOAA, but that doesn’t matter to CO2-obsessed warmists trying to claim the atmospheric tail wags the oceanic dog.
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An opinion article published yesterday in Frontiers in Earth Science rebuts a recent paper by Michael E. Mann et al. who deny the existence of long known drivers of natural climate variability like the Pacific decadal oscillation (PDO) and the Atlantic multidecadal oscillation (AMO), reports The Global Warming Policy Forum (GWPF).

Applying habitual methodological shenanigans, they claim that the PDO is not distinguishable from noise and that the AMO is due to anthropogenic aerosol emissions rather than any intrinsic climate oscillation.

In her critique, Professor Müller-Plath not only highlights the methodological flaws in the Mann et al. paper but also shows that their aerosol hypothesis has long been rejected in the scientific literature, research papers Mann et al. simply ignore.

‘Moderate to strong’ La Niña weather event develops in the Pacific

Credit: concernusa.org

Even the normally alarmist BBC has to admit that ‘a La Niña event normally exerts a cooling influence on the world’. Add in a deep solar minimum and things could get interesting, with varying regional effects.
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A moderate to strong La Niña weather event has developed in the Pacific Ocean, according to the World Meteorological Organization (WMO).

The naturally occurring phenomenon results in the large scale cooling of ocean surface temperature, says BBC News.

This La Niña, which is set to last through the first quarter of 2021, will likely have a cooling effect on global temperatures.

But it won’t prevent 2020 from being one of the warmest years on record.

La Niña is described as one of the three phases of the weather occurrence known as the El Niño-Southern Oscillation (ENSO).

This includes the warm phase called El Niño, the cooler La Niña and a neutral phase.

Niklas Mörner: 1938-2020

Our friend Niklas Mörner has passed away. We must raise our game and work to honour the memory of this bright, brave and brilliant man. The energy and clarity of purpose he brought to science is an inspiration to us all. The humour and kind hearted cameraderie he exuded bound all the events we organised together. His enthusiasm was infectious, his expertise unparalleled in his field. His ability to engage audiences and communicate complex topics in a way that left participants with new insight is legendary.

He swung the sword of truth with grace.

Large-scale changes in Earth’s climate may originate in the Pacific

Some interesting theorising arises from this research, but as one expert commented: “These new data may raise more questions than they answer.” At least one existing belief about long-term climate change finds itself challenged.
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The retreat of North America’s ice sheets in the latter years of the last ice age may have begun with “catastrophic” losses of ice into the North Pacific Ocean along the coast of modern-day British Columbia and Alaska, scientists say.
[Science News reporting].

In a new study published October 1 in Science, researchers find that these pulses of rapid ice loss from what’s known as the western Cordilleran ice sheet contributed to, and perhaps triggered, the massive calving of the Laurentide ice sheet into the North Atlantic Ocean thousands of years ago.

That collapse of the Laurentide ice sheet, which at one point covered large swaths of Canada and parts of the United States, ultimately led to major disturbances in the global climate (SN: 11/5/12).

The new findings cast doubt on the long-held assumption that hemispheric-scale changes in Earth’s climate originate in the North Atlantic (SN: 1/31/19).

Ocean carbon uptake widely underestimated, say researchers

The ocean carbon cycle [credit: IAEA]

Shockingly – for some – nature’s ocean carbon cycle is functioning quite well, despite constant attempts by feckless humans to undermine it [/sarc]. Time to revisit those troublesome computer models yet again.
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The world’s oceans soak up more carbon than most scientific models suggest, according to new research, reports Phys.org.

Previous estimates of the movement of carbon (known as “flux”) between the atmosphere and oceans have not accounted for temperature differences at the water’s surface and a few metres below.

The new study, led by the University of Exeter, includes this—and finds significantly higher net flux of carbon into the oceans.

It calculates CO2 fluxes from 1992 to 2018, finding up to twice as much net flux in certain times and locations, compared to uncorrected models.

Florida current is weaker now than at any point in the past century

Image credit: NASA

And by coincidence (?) so is the sun.
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A key component of the Gulf Stream has markedly slowed over the past century—that’s the conclusion of a new research paper in Nature Communications published on August 7, says Phys.org.

The study develops a method of tracking the strength of near-shore ocean currents using measurements made at the coast, offering the potential to reduce one of the biggest uncertainties related to observations of climate change over the past century.

“In the ocean, almost everything is connected,” said Christopher Piecuch, an assistant scientist in the Physical Oceanography Department at the Woods Hole Oceanographic Institution (WHOI) and author of the study. “We can use those connections to look at things in the past or far from shore, giving us a more complete view of the ocean and how it changes across space and time.”

Piecuch, who specializes in coastal and regional sea level change, used a connection between coastal sea level and the strength of near-shore currents to trace the evolution of the Florida Current, which forms the beginning of the Gulf Stream.

The Gulf Stream flows north along the Southeast Atlantic Coast of the United States and eventually east into the North Atlantic Ocean, carrying heat, salt, momentum, and other properties that influence Earth’s climate.

Because nearly continuous records of sea level stretch back more than a century along Florida’s Atlantic Coast and in some parts of the Caribbean, he was able to use mathematical models and simple physics to extend the reach of direct measurements of the Gulf Stream to conclude that it has weakened steadily and is weaker now than at any other point in the past 110 years.

One of the biggest uncertainties in climate models is the behavior of ocean currents either leading to or responding to changes in Earth’s climate. Of these, one of the most important is the Atlantic Meridional Overturning Circulation, or AMOC, which is a large system or “conveyor belt” of ocean currents in the Atlantic that includes the Gulf Stream and that helps regulate global climate.

Piecuch’s analysis agrees with relationships seen in models between the deeper branches of the AMOC and the Gulf Stream, and it corroborates studies suggesting that the deeper branches of AMOC have slowed in recent years.

Full article here.

Solar cycle 14 – was the fourteenth solar cycle since 1755, when extensive recording of solar sunspot activity began. The solar cycle lasted 11.5 years, beginning in January 1902 and ending in July 1913. The maximum smoothed sunspot number (SIDC formula) observed during the solar cycle was 107.1, in February 1906 (the lowest since the Dalton Minimum) – Wikipedia

Still waiting for greenhouse: No response to my last email to Roy Spencer

Before the last time I had to dive deeply into politics to defend the EU referendum result, I had an email conversation with Roy Spencer in an attempt to resolve the conflict between physicists like himself, who believe the radiative greenhouse theory is correct, but it’s effect small, and physicists like Ned Nikolov, who contend that the theory is fundamentally incorrect.

After a couple of to and fro emails I sent this response in Feb 2019, to which I never received a reply. It’s time we got this discussion back out in the open, because Boris’ green reset #netzero plan for the UK post Brexit and post pandemic is set to ruin our economy and cause untold suffering, deprivation, and death.

the lukewarmers have utterly failed to convince the fanatics that although they think their theory is correct (it isn’t, but that’s their misguided opinion), they’ve overestimated the magnitude of the effect.

It’s time they stopped supporting the fanatics by deploying false arguments against better theory which will exonerate CO2 and move the debate away from ridiculous and expensive ‘mitigation’, and forward to adaption to the effects of natural climatic change.

Island ‘drowning’ is not inevitable as sea levels rise

Another bunch of climate alarmist predictions get exposed as over-the-top doom-mongering — literally, in this case.

Coral reef islands across the world could naturally adapt to survive the impact of rising sea levels, according to new research reported at Phys.org.

Coral reef islands across the world could naturally adapt to survive the impact of rising sea levels, according to new research.

The increased flooding caused by the changing global climate has been predicted to render such communities—where sandy or gravel islands sit on top of coral reef platforms—uninhabitable within decades.

However, an international study led by the University of Plymouth (UK) suggests that perceived fate is far from a foregone conclusion.