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Wednesday, July 13, 2022

Attenborough’s “Breaking Boundaries” documentary; Distorting Science to Shill for One World Government

 

Welcome everyone



Below is thee  transcript for  

Attenborough’s “Breaking Boundaries” documentary; Distorting Science to Shill for One World Government

View at https://youtu.be/w8IbgqVgxP8


Today I will look at how one of my environmental heroes is now betraying the science. When I taught ecological classes, I would eagerly incorporate many of Attenborough’s beautiful wildlife videos.

But after just recently viewing his 2021 video, "Breaking Boundaries: the science of our planet", I’ve been disturbed, to see Attenborough’s magnificent cinematography increasingly used to distort the science, instill fear and shill for “a globalist agenda”

The video alternates between parallel narratives from Attenborough and narratives by a Swedish scientist, Johan Rockstrum. Together they pushed a myth that we are turning a planet that was once our friend, into a planet that is our foe.



But anyone with the least amount of knowledge about earth's history knows the earth has always been both friend and foe to wildlife and humanity. Deadly weather commonly unleashed throughout history, eliminated all that did not adapt, causing mass extinctions and collapsing civilizations.

Oddly, Attenborough argues that by simply adhering to globalist Johan Rockstrum’s planetary boundaries, we can save the world.

And like all demagogues and false prophets, he offers a utopian fantasy that his guidelines ensure the earth remains the "perfect home.”






Attenborough and Rockstrum begin by suggesting that this graph of Greenland’s ice core temperatures is science’s most important and most relevant for guiding human civilization.

Rockstrum points to the great instability of temperatures over the past 100,000 years during the last glacial maximum. The numbered peaks are Dansgaard–Oeschger events, caused when accumulating ocean heat that had been transported from the tropics into the Arctic, periodically melted enough of the insulating ice to let heat ventilate, causing temperatures to rapidly rise by 10 ºC (18 ºF) in just 10 years. That instability, Rockstrum claimed caused great environmental hardships for humans.

But during the most recent 11,7000 years, a period called the Holocene, the average temperature stabilized, and varied only by plus or minus 1 °C. However they don’t mention that stability was due to less ice.

Despite the fact that humans did not create the Holocene, they suggest humans can now magically maintain the Holocene’s stable climate, if only we follow Rockstrum’s guidelines and keep the earth within his so-called 1 ºC planetary boundary.



Attenborough repeats a false narrative that he frequently espouses, bemoaning, "The Holocene has ended. The garden of Eden is no more. We have changed the world so much that scientists say we are in a new geological age: the Anthropocene, the age of humans"

Therefore, to prevent further catastrophes and return to Eden our “immediate priority, is to reduce carbon emissions to zero and stabilize temperatures as low as we possibly can”

In contrast, according to the executive committee of the International Union of Geological Sciences, the official group of scientists who define the earth’s geological ages, the Holocene has not ended. And despite political efforts by some scientists to declare the Anthropocene as an official age in order to highlight humanity's negative impacts, there has yet to be any consensus on the proposal that the Holocene has ended.



Instead of formalizing the Anthropocene, the International Union of Geological Sciences officially defined 3 distinct ages of the Holocene The first 2 ages are defined by dramatic changes in Greenland’s ice core. Accordingly, the Greenlandian Age began 11,700 years ago marking the end of the last glacial maximum, the re-arrangement of ocean and atmospheric circulation and a rapid warming of about 10 degrees Celsius. Furthermore, the transition from the Pleistocene’s last glacial maximum into the Holocene resulted in one of the world’s greatest mass extinctions, mostly of large animals, and the loss of biodiversity.

In contrast to Attenborough’s stable Garden of Eden, Greenland’s ice cores also reveal just how unstable the Holocene climate has truly been.



The Northgrippian Age, named after the location of one ice core, began when temperatures plummeted to the lowest point in the entire Holocene 8,200 years ago. Temperatures then rose, reaching 1 to 2 degrees Celsius warmer than today, that warm period has been informally called the Holocene Climate Optimum. Then a cooling and drying trend occurred that established many of the world's deserts.

The most recent period, the Meghalayan began 4,200 years ago marked by a 200-year global mega-drought that collapsed many Eurasian civilizations, as well as a megadrought in sparsely populated North America, stretching from Massachusetts to Idaho.

Indeed, it has been droughts and famine, during cooling trends that have destabilized the environment and human civilizations.

The Meghalayan’s cooling trend was interrupted by warm spikes lasting several decades such as the Roman and Medieval Warm Periods. In addition, more intense El Nino and La Nina events evolved. Such instability has made it difficult for scientists to determine if recent extreme weather events are just more of the same, or perhaps signal an end of the Holocene and the start of the Anthropocene.



During the Greenlandian Age, the Sahara was a rich grassland with scattered shallow lakes, supporting a wealth of wildlife that supported several tribes of hunters and gatherers. Those stone age people celebrated that abundance of wildlife in numerous cave paintings




But around 6000 years ago as rainfall decreased, the green Sahara transitioned to the Sahara Desert, again greatly reducing biodiversity, and forcing humans to seek more hospitable conditions elsewhere.



The Sahara’s reduced rainfall was largely caused by a shift in the location of the Intertropical Convergence Zone, or ITCZ. The location of the greatest solar heating within the global tropics, causes intense currents of rising air which then draw in moist surface air from the north and south via the Trade Winds, and concentrates that moisture where the winds converge.




As the moist air rises, cools and condenses, that moisture rains out, bringing a heavy rainy season to the land below. The remaining dry air continues to circulate, eventually sinking further to the north and south, bringing deserts and arid climates to those regions below.

The ITCZ moves seasonally with the sun Bringing a rainy season to the tropics north of the equator during June and July, while simultaneously causing a tropical dry season south of the equator.




By December and January, the ITCZ has brought a rainy season south of the equator, leaving a dry season to the north

In addition, the ITCZ also migrates over millennia due to the sun's orbital cycles. Throughout the Holocene, the ITCZ has exhibited a trend that has continuously contracted southward, and it is that migration that reduced the rains that once supported a green Sahara.




In response to the Holocene’s drying trends, humans either perished or moved to the great river valleys where ample water enabled civilizations to continue. Great civilizations emerged in the mid Holocene along China's Yellow River, within India and Pakistan’s Indus River Valley, and along Egypt’s Nile River. Great Stone Age civilizations emerged in Mesopotamia along the Tigris and Euphrates rivers. 




But as the ITCZ continued to migrate, the Akkadian empire in northern Mesopotamia and dependent on rainfall, collapsed during the 200-year drought that marks the beginning of the Holocene’s Meghalayan Age.    Regional rainfall decreased by 20-30% and water levels of the Dead Sea abruptly fell by 100 meters.

The Old Kingdom of Egypt, also known as the Age of Pyramids, also collapsed as drought reduced the Nile River's flow and the floods that had previously renewed the fertile soils and maintained Egypt’s agriculture.



Late Bronze Age civilizations such as those that flourished in Greece, or Troy or had re-emerged in Egypt, collapsed due to megadroughts 3,200 years ago

The greatest droughts and deadliest famines occurred during conditions of low CO2 and cooler temperatures of the Little Ice Age, under the very conditions that Attenborough and Rockstrum argue that we must return to.

The Great El Nino and resulting droughts of the 1790s devastated east India and caused widespread civil unrest. The Victorian Great Drought of 1876 resulted in 30 million deaths The mid–1700s Strange Parallels Drought caused famine and substantial societal upheaval across southeast Asia, India, and the Siberian plains.




Climate change during the Little Ice Age also brought murderous diseases such as the Bubonic Plague, but that was never mentioned by Attenborough. Instead, despite mounting evidence that the Covid pandemic was caused by an escaped virus designed in China's Wuhan laboratory by medical experts whose gain of function research was globally funded, Attenborough featured a cholera expert who fear mongered that the Covid epidemic is evidence of the world exceeding our planetary boundaries.

Yet the Bubonic Plague, the greatest killer of all, that had truly been affected by climate change, was ignored. That plague killed over 200 million people worldwide, even though we were well within Rockstrum’s climate boundary. The Bubonic Plague periodically disappears when temperatures rise above 81.5 ºF (27.5℃), because its transmission is greatly reduced by that warmth. But that fact does not support Attenborough’s CO2 driven global warming climate crisis narrative




Furthermore, La Ninas drive Asia’s wet periods, increasing vegetation and promoting greater rodent populations. In turn, more rodents support more fleas that transmit the deadly bubonic bacteria. When El Ninos bring dry periods that reduce the Asian rodent population, flea populations are forced to seek other hosts and so bite and infect other animals and people.

By the end of the video the reason for Attenborough’s sins of omission and fear mongering become clear. By Rockstrum’s own words, they reveal their true motive for the video's "end of the world" fear mongering.




They want Rockstrum’s planetary boundaries to be the guide for a global governance that could be enforced by the United Nations Security Council.

The natural causes of climate change, a migrating ITCZ, the El Nino cycles of droughts and famines, or the cool conditions that enabled several Bubonic Plague outbreaks, don’t support their arguments that there is a need for a world government, and so, get ignored.

Like all demagogues and false prophets, Rockstrum combined climate fear with a promised utopia, but only if we follow their mandates. He promises clean air, healthier children, longer life spans, stable markets, stable jobs, and less conflicts. But such pie-in-the-sky promises should make all sane people wonder just how badly his politics have biased his science.

Unsurprisingly, Rockstrum is on the board of directors of the "global challenges foundation" whose founder states, “our intention is to start a debate on the need for an international political system” …"the need for a world government” … “one that can enforce its rules”

Rockstrum is also on the board of the "Eat Foundation" that proudly announces it is working to build consensus for a grand food system transformation. You got to wonder what could go wrong when such experts' control the economy? Well, Venezuela, Ghana, and now Sri Lanka quickly come to mind?



The Holocene’s southward migration of the ITCZ also caused increasing climate instability by promoting greater El Nino and La Nina event
s. Alternating El Nino-like and La Nina-like ocean temperatures in the Pacific cause a natural global see-saw of droughts, floods, and heatwaves, but those events have been falsely portrayed as evidence of co2 driven climate instability.

During La Nina-like conditions, strong trade winds cause warm water to pile up in the western Pacific and Indian Ocean warm pools, promoting strong summer monsoon rainfalls that sustain the crops that feed half the world's population. La Nina-like conditions may only last a few years, or for 30 or more years during a negative Pacific Decadal Oscillation, and even longer when strong solar irradiance strengthens the Trade Winds. Simultaneously, La Nina-like conditions force cooler surface temperatures due to upwelling in the eastern Pacific Ocean, which then promotes descending dry air and drought conditions over portions of western North and South America.




Conversely during El Nino-like conditions, warm water stored in the warm pools, more readily slosh eastward, surfacing somewhere between the central and far eastern pacific, bringing heavy rainfall to the Americas but drought to Asia and Australia. El Nino-like conditions dominate during periods of a positive Pacific Decadal Oscillation or periods of weak solar irradiance as was the case during the Little Ice Age sunspot minimums.

Cooler little ice age temperatures and low CO2 concentrations, never spared the world from massive droughts, famine, or collapsed civilizations and millions of deaths.

.



The El Nino-like conditions that dominated the 1300s and 1400s, brought decades-long droughts that collapsed Cambodia’s Khmer empire, as well as the  Victorian Great Drought and other previously mentioned droughts.

During more La Nina-like conditions during the Medieval Warm Period, extreme drought conditions in the American southwest forced the Anasazi civilization to abandon that region.



To achieve their political aims, demagogues and false prophets always fear monger impending doom. Edmund Burke warned in the 1700s “no passion so effectually robs the mind of all its powers to act, ...and to reason, ...as does fear.”

Tragically, instead of educating the public about the complexities of Holocene climate change and droughts, Attenborough chose to stunt the public's ability to reason by pushing fear. To that end, he included parts of a speech by Greta Thunberg, the teenage actress who first learned to fear climate change at the ripe old age of eight years old.

Although the media has systematically denigrated and silenced knowledgeable skeptical scientists, Greta’s handlers easily featured her so-called in-depth knowledge of climate science at the "World Economic Forum" in 2019 at Davos. 

Her words are repeated in his video, clearly echoing Attenborough’s intent! Greta ranted “I don't want you to be hopeful. I want you to panic, I want you to feel the fear I feel everyday”



Like most mainstream media, every bad weather event becomes a click-bait story about the impending doom of climate change. The NY Times reviewed "Breaking Boundaries", calling it a documentary about the end of the world. Although many outlets criticized the video's animations and presentation style, mainstream media never challenged its abundant distortions and misleading omissions.

Likewise, in the political struggle for power in the USA, the Senate Democrats created the "Special Committee on the Climate Crisis". Their goal was not to uncover the truth by fostering robust scientific debate, but to shut down debate. As their first priority clearly stated, the Committee's purpose was to provide "oversight and investigation of the efforts of special interests to foster climate denial". Gee, how dare our democracy allow citizens to challenge the climate crisis fears pushed by demagogues.



So, it is not surprising that the NY Times just published on July 8, 2022, an article titled “Democrats can win [upcoming elections] if they Embrace the Politics of Fear”. Accordingly, climate fear has been a staple of so many democrat politicians and policies.

Finally, one last example of how Attenborough and Rockstrum distorted the science. Early in the video's narratives they claimed the polar ice caps reflect just the perfect amount of sunlight to prevent the earth from overheating. But now the warming and melting from rising CO2 is disrupting that perfect balance. Yet the history of Greenland’s ice cap tells a very different story.



During the early Greenlandian age, Greenland’s glaciers were still growing. But during the Northgrippian age, glaciers such as the Jakobshavn retreated 100 meters per year and its margin remained behind the glacier's current boundary for 7000 years. Despite reflecting much less sunlight than Attenborough’s perfect balance would suggest, that lack of polar ice never triggered a tipping point or runaway warming. Instead, the earth entered a cooling trend. The recent Meghalayan age had been informally called the neo-glacial as glaciers expanded at higher latitudes with maximum extents culminating in the Little Ice Age.

But due to natural climate oscillations, glacier growth and retreat has oscillated. Between 1960 and 1990, the Jakobshavn did not retreat, and Greenland gained ice.

Similarly, alternating periods of ice growth and retreat, frequently happened between 6500 and 2600 years ago as summer sea surface temperatures alternated between 2–4 °C cooler to 6 °C warmer than present while sea ice ranged between 2 months more ice and 4 months more open water than today. Accordingly, the so-called paleo-Eskimo cultures periodically abandoned and reclaimed the arctic ocean's coastal habitats. So, is the current loss of arctic sea ice simply a continuation of the Holocene’s natural oscillations?

Scientists tell a similar story about Norway’s glaciers that completely melted away at least once during the Holocene. The Hardangerjøkulen glacier, seen here, (and I do apologize to native Norwegian speakers for any mispronunciations) it melted away 8000 years ago when the mean summer temperatures were 1 °C higher than today. 



 The Jostedalsbreen glacier melted away 7600 years ago when mean summer temperatures were 0.7 °C warmer than today.



But most informative, the Folgefonna glacier melted away 9700 years ago when temperatures were similar to today but precipitation, had been reduced by 70%.



Likewise, glacier advances and retreats during the little ice age, in both the Swiss Alps and Africa’s Kilimanjaro, have correlated with changes in precipitation, as evidenced by simultaneous changes in surrounding lake levels. And despite the doomsday narratives, correlations between temperature and ice extent are often lacking. Yet again, Attenborough and Rockstrum ignored those scientific observations so they can push their warming crisis.

Climate truths will always be resisted by those who profit from fear and those who have been naively convinced by chicken little scientists and cinematographers. But the truth will set you free. Indeed, these truths provide the critical thinking to minimize to what degree you will be manipulated by dishonest political agendas. 

So please, share these truths!



Our democracy depends on a diverse array of good critical thinkers. So, please shun mindless group think.

Instead embrace renowned scientist, Thomas Huxley’s advice Skepticism is the highest of duties and blind faith the one unpardonable sin.


Wednesday, October 20, 2021

Pt 2: How Sea Ice Controls Arctic Heat Ventilation and Arctic Air Temperatures



Watch youtube video Pt 2: How Sea Ice Controls Arctic Heat Ventilation and Arctic Air Temperatures


https://youtu.be/bm8UcrOQoso


Below is the transcription of the video




Welcome 

Today, I'm looking at part two,  how sea ice controls the ventilation of heat from the Arctic ocean and the Arctic's air temperatures. 

Now there are three major factors affecting sea ice extent and thus Arctic temperatures. The first, as detailed in part one, the volume of inflowing warm Atlantic water into the Arctic has correlated with sea ice extent for decades and millennia. The warm inflow circulates inside the Arctic for 25 to 30 years and peer reviewed studies such as Polyakov (2017) have determined there is currently enough heat flowing into the Arctic to completely melt all the sea ice.

However, the heat of the inflowing Atlantic water has no effect on air temperature, if sea ice insulates that warmth from the atmosphere. Furthermore, the layers of fresher water, such as the inflowing Pacific water float above the warm Atlantic water, and also insulate the ice and the atmosphere from warmer subsurface temperatures.



The warm inflows create a warm subsurface Atlantic water between about 150 and 900 meters.

Due to the effects of saltiness, the melting point of Arctic water is a negative 1.8 degrees centigrade or 28.8 Fahrenheit. But peer reviewed study such as Shu (2019) has determined the warm water entering Arctic via the Fram Strait is much higher, about three degrees centigrade or 37.4 Fahrenheit, easily melting sea ice.

As the Atlantic water circulates around the Arctic heat ventilates from the open water and the thinner ice, and warms the air while it is cooling to about 0.4 degrees centigrade; still warm enough to have melt sea ice. However, regions with thick multi-year sea ice will insulate Atlantic water heat from radiating back to the atmosphere. Now the 3 degrees of inflowing heat through the Fram Strait thins the sea ice along its Eurasian coast pathway. But as the heat ventilates into the atmosphere, the inflowing water cools to 0.4 degrees centigrade. So sea ice in the Central and Western Arctic tends to be thicker than in the Eastern Arctic. 




But before that 3 degrees centigrade Atlantic water reaches the Fram strait,  water entering the Arctic circle (designated by this red line) is much warmer and has been keeping most of the Greenland, Norwegian and Barents eSeas free of winter ice. Now, the effects of thicker sea icce explains the results of a peer reviewed paper published in 1993 in the esteemed scientific journal Nature. Researchers measuring air temperatures over Western and central Arctic ice, found no warming over a period of 40 years and even a slight cooling.

So they reported no evidence of any greenhouse warming.


The effect of sea ice on Arctic temperature is more dramatically exhibited by the  Dansgaard-Oeschger events.                                                                                    

Between our current warm interglacial and the previous warm inter-glacial, there is the cold 100,000+ year glacial period. A closer look at that glacial period reveals over 20 rapid warming Dansgaard-Oeschger events, during which air temperature rose by an incredible 5 to 15 degrees centigrade or 9 to 27 Fahrenheit in just a few decades.



And despite a heavily glaciated Northern hemisphere, temperatures were almost as warm as the final warm event that led to the present warm into glacial.

Now there are several hypotheses, all of which may be in play explaining why se ice suddenly released ocean heat to produce those warm Dansgaard-Oeschger events. Some hypothesize that these warm events were caused by an increase in warm water inflows. 

Other suggests because thicker ice was preventing heat from ventilating as their temperatures cooled, sub surface temperatures increased to the point it melted the ice. 

And also as the glaciers grew covering the land from Chicago to Boston, with ice a half a mile thick,  sea level fell creating the Bering Strait land bridge that allowed humans to migrate from Asia to north America, but it also lowered sea level and blocked the inflow of fresher Pacific water.



And without the insulating layer of Pacific water, the warm Atlantic water had a greater direct contact with sea ice, which was then melted more readily.


In our present interglacial, sea ice grows each winter and then it melts each summer.

But typically only the thin first year sea ice represented by the purple color is lost, allowing heat to ventilate. The following winter, summer's open water is covered again by the new ice.  




Thick multi-year sea ice only grows where slabs of ice pile on top of one another, especially where ice slabs are pushed against the Northern Greenland coast or the Canadian Islands as represented by non purple colors. That is where the thickest four-year-old and older ice is maintained. And the bulk of that multi-year ice large is largely unaffected between winter and summer temperatures. However, the amount of thick ice can be greatly altered by the winds of the natural Arctic oscillation, which varies on timescales from weeks to decades to millennia

Peer reviewed science by Ignatius Rigor determined that in 1989, the positive phase of the Arctic oscillation became more dominant and removed thick multi-year ice from the Arctic allowing more heat to ventilate from the subsurface causing the recent rapid Arctic warming.





Now previously in the 1970s and eighties, when the negative phase dominated winds, trapped sea ice inside the Beaufort Gyre, seen in the lower yellow curve, increasing the amount of colliding and overlapping ice.

Along the Eurasian coast, the cold Siberian winds guided the Transpolar Drift (TPD) the upper yellow curve, which primarily carried just thin first-year ice out of the Arctic through the Fram straight to melt in the Atlantic 

The 1989 switch to the positive phase caused a Transpolar Drift to dive deep into the center of the Arctic. Following the path of the red curve seen here and then drove increasing amounts of thick multi-year sea ice out of the Arctic into the Atlantic, through the Fram Strait.

Ocean and atmospheric circulation are clearly the critical climate dynamics, controlling sea ice, heat ventilation, and Arctic warming. But those dynamics are the elephants in the room, rarely addressed by a mainstream media bent on pushing clickbait, driven by climate crisis headlines.





So to summarize 

Presently warm Atlantic inflows mediate sea ice extent and maintain the warm subsurface Atlantic water layer. 

The release of heat from the surface is largely mediated by sea ice thickness. The varying winds driven by the Arctic oscillation can either trap and grow thick ice or remove thick ice 

Combined, those two dynamics have reduced sea ice extent in recent decades, allowing more subsurface heat to ventilate. The ventilating heat cools the ocean while warming the Arctic air.  Higher temperatures caused by a cooling ocean should NEVER be added to a global average temperature that's intended to measure increasing stored heat. 

And although it's true, more ventilation made available more heat available to be recycled via the greenhouse effect, that dynamic is relatively insignificant. Rising CO2 attribution is the media's way of having the tail wag the elephant.

Ocean and atmospheric circulation are by far the most significant drivers of sea ice changes and Arctic warming.

I emphasize again,  ocean and atmospheric circulation are the most significant drivers of the so-called Arctic amplification. 

Up next In part three, I'll examine how the sun affects the amount of warm tropical waters flowing into the Arctic. 

And until then embrace Thomas Huxley's advice "That skepticism is the highest of duties and blind faith, the one unpardonable sin."

 And if you appreciate the science clearly presented here, science rarely presented by mainstream media.

Then please give it a, like, give it a share or copy the URL of the video and email it to friends, subscribe to my channel or read my book, landscapes and cycles and environmentalist journey to climate skepticism.

 Thank you.


Thursday, January 2, 2020

When Warming is Cooling!

published in the Pacifica Tribune, December 30, 2019


What’s Natural?

When Warming is Cooling!






The media has been awash with doomsday headlines, trumpeting a human-caused “climate crisis” simply because the estimated average global temperature has risen about 1.7°F since the end of the cold Little Ice Age 150 years ago. However, the Arctic has been the greatest climate outlier and its much warmer temperatures, averaging 3.6°F higher than the 1951–1990 average, has shifted the global warming average upwards. 

Furthermore, increased ventilation of stored ocean heat has contributed to much of the Arctic’s recent high temperatures. Ventilating heat warms the air but cools the ocean, and climate history reveals ventilating heat has caused several bouts of extreme warming. Over the past 100 thousand years Greenland’s ice cores recorded 24 extreme warming episodes when air temperatures suddenly rose 14°F - 28°F in a few decades or less. More recently over 4000 years in the Canadian Arctic, decades of rapid ice loss accompanied air temperatures 3°F -10°F warmer than today, quickly followed by centuries of more sea ice and colder temperatures. Although the physics of those dramatic warming events are still in play today, the good news is: warming climates minimize such dramatic warm events.

The most extreme Arctic warming episodes were named “Dansgaard-Oeschger events” in honor of two scientists who discovered them. Although Greenland experienced the greatest warming, Dansgaard-Oeschger events affected climates globally. Ventilating warmth changed global atmospheric circulation, shifting European forests and altering California’s ocean currents. Counter-intuitively, each Dansgaard-Oeschger extreme warming event happened during the last Ice Age when the northern hemisphere was covered with great ice sheets and global temperatures were 5°F-14°F colder than pre-industrial times

The climate dynamics responsible for these dramatic warm events is easily demonstrated, and a simple experiment might ease the troubled minds of students plagued with “climate crisis” anxiety. Heat a large covered pot of water. Measure the air temperature above the pot’s lid. If you don’t have a thermometer, simply hold your hand above the lid. Then remove the lid and feel the escaping heat. In a similar fashion, Arctic sea ice (and a surface layer of fresher water) act like the pot’s lid. Remove the ice and the air dramatically warms. Conversely, extensive ice-cover will cool the air but warm the underlying ocean.

Ocean currents constantly transport tropical heat towards the poles, making Arctic climates far warmer than possible if only the sun and greenhouse gases controlled the Arctic’s climate. Warm dense “Atlantic water” constantly enters the Arctic Ocean. Some heat ventilates but some is stored at intermediate depths. Currently there is enough stored heat to melt sea ice many times over. The extensive sea ice of the last Ice Age insulated the Arctic Ocean causing heat to increasingly accumulate. Eventually that great store of heat melted sea ice from below, allowing heat to vent and greatly warm the atmosphere. 

The same dynamics triggering past Dansgaard-Oeschger events provide insight into today’s Arctic warming. During the 1970s and 80s, measurements over an ice covered Arctic recorded cooling air temperatures prompting researchers to publish, “Absence of Evidence For Greenhouse Warming Over the Arctic Ocean In the Past 40 Years.” Those cooling air temperatures did not reduce modern Arctic sea ice. But other factors did.

Arctic winds can trap ice in the Arctic causing ice to thicken. However when the winds shift, thick sea ice will be blown out and melt in warmer Atlantic waters. The resulting open water and thinner ice allows more Arctic subsurface heat to ventilate. In addition to wind-driven ice loss, satellites reveal the greatest area of open Arctic waters corresponds to the pathway where warm dense tropical waters, via a branch from the Gulf Stream, enter the Arctic and melt sea ice from below. It is now widely believed high inflows of warm Atlantic water helped to melt sea ice and trigger the Dansgaard-Oeschger warm events, just as oscillating warm inflows now melt Arctic sea ice today.

A new monitoring system established off the coast of southern Florida in 2002, reports warm water increasingly flowed towards the Arctic until 2008, but since then warm inflows have been decreasing. So, we will now witness a natural experiment that tests competing climate hypotheses. If the increasing inflows of warm water caused most of the Arctic’s recent sea ice loss, then reduced flows should allow sea ice to recover within another decade. In contrast, the competing hypothesis is warming from increasing CO2 concentrations will cause an ice-free Arctic Ocean. Early predictions of an ice-free Arctic have already failed. But many still predict an ice-free Arctic by 2030 or 2050. Of greater interest, if sea ice does recover, will the reduction of Arctic heat ventilating to the atmosphere, also reduce global temperatures and avert the ballyhooed “climate crisis”?


Jim Steele is director emeritus of the Sierra Nevada Field Campus, SFSU and authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism





Wednesday, May 29, 2019

Cycles of Rapid Climate Warming




Published in the Pacifca Tribune May 28, 2019

What’s Natural

Cycles of Rapid Climate Warming

The globally averaged temperature rose 1.5°F from 1880 to today. Various narratives suggest the rise since 1950 was driven by increasing concentrations of CO2. The rising temperature before 1950 was considered natural. Since 1990, Arctic temperatures rose 2 to 3 times faster than the global average. So, are rapidly rising Arctic temperatures evidence of an impending climate crisis? 

Astute students of climate history recall rapid Arctic warming has happened often and naturally. During the last Ice Age when COconcentrations were just half of today’s, 25 abrupt warming eventshappened. Arctic temperatures rose 9°F, and sometimes as much as 14°F in just 40 years. These rapid warming episodes are now called Dansgaard–Oeschgerevents (D-O events) in honor of the researchers who first detected them in Greenland’s ice cores. These D-O episodes affected global climate, changed ocean currents along California’s coast and altered the range of European forests.


What caused such abrupt warming? Basic physics dismisses changes in greenhouse gases or solar insolation because neither radiative effect induces such rapid warming. The most reasonable explanation suggests episodes of ventilating heat, that had accumulated in the Arctic Ocean, rapidly warmed the air. 

The notion of stored heat in a freezing Arctic Ocean seems unfathomable to many laypeople. But it is scientifically well documented.Tropical Atlantic waters experience intense heating and evaporation. This results in warm salty water that is relatively dense. The Gulf Stream and its branching currents then transport that warm water northward. Because the water is salty and dense it sinks below colder and fresher surface waters as it approaches the Arctic Ocean. As a result, there is a layer of warm Atlantic water stored at depths between 300 and 2,700 feet below the Arctic Ocean’s surface.Arctic researchers report, “the total quantity of heat is substantial, enough to melt the Arctic sea ice cover several times over.”


Warm Atlantic Water in the Arctic Ocean



Sea ice and a layer of cold fresh water normally inhibit subsurface heat from ventilating to the atmosphere. But as the incoming heat increases and accumulates, the warm Atlantic Waters can eventually melt the overlying ice cover. Other times, changes in the direction of Arctic winds will blow sea ice out into the Atlantic, as it did in the late 1990s. Either way, without insulating ice, a burst of heat ventilates from the ocean and warms the atmosphere. 

Recently, anthropologists studying past Arctic cultures found the pre-Dorsett culture periodically abandoned then recolonized the Arctic coast as changes in sea ice affected temperatures. When sea ice covered coastal waters for 2 months longer than today, temperatures became 3-7°F cooler. Arctic people then abandoned the coast and moved south. A few hundred years later they re-colonized the coast when periods of open water, lasting 4 months longer than today, allowed heat to ventilate and raise temperatures 10°F warmer than today.  Such changes alternated over several hundred years. And that raises the question, is the Arctic still experiencing similar cyclical warming?

Over the past several hundred years, melting Arctic sea ice corresponds with observed periods of increased intrusions of warm Atlantic waters. The dramatic Arctic warming during the 1920s and 1930s corresponded with increased intrusions of warm water accompanied by Atlantic fish species normally found further south. As the 1922 newspaper clipping reveals (see above), the warming of the Arctic was so dramatic it raised concerns the frigid Arctic would soon be converted to a warmer “temperate zone”. 

Arctic 1922


When warm water inflows began retreating around 1950 so did the Atlantic fish. Sea ice then increased.  Such cycles have been recorded infishery data for hundreds of years. The most recent cycle of melting Arctic sea ice likewise coincided with intruding warm Atlantic waters with patterns of invading fish very similar to the 1920s-1930s warming episode.

So, we are now in the midst of an instructive natural experiment. If the loss of Arctic sea ice and warmer temperatures are due to rising CO2concentrations, we should soon see a total loss of Arctic sea ice as predicted by some climate scientists. In contrast, if natural oscillations are controlling intrusions of warm Atlantic waters, Arctic sea ice will soon rebound. Indeed, a recent shift in ocean oscillations is now decreasing warm water intrusions. Temperatures should fall as less heat ventilates into the atmosphere. Based on earlier 20thcentury patterns when lost sea ice rebounded in the 1960s and 70s, Arctic sea ice should begin rebounding by the year 2030. But then again, warmer temperatures did last for 300 years during cycles a few thousand years ago. Either way, natural climate cycles predict Arctic temperatures will not experience further accelerated warming. We will soon see which theory is most accurate within the coming decade.


Jim Steele is retired director of the Sierra Nevada Field Campus, SFSU