Wednesday, October 21, 2020

Dire Scientific Warnings from the Study of Fossilized Shells

A slew of recent studies corroborate the scientific consensus on climate change. It is both a current day reality and a serious threat to life on Earth. In recent decades we have witnessed a sharp increases in the number of floods, storms, heat waves, droughts, hurricanes and wildfires. This is corroborated by the daily news which shows wildfires in the West and storms in the East. Thus far in 2020 we have seen 25 named storms in the Atlantic, making this only the second time that the the World Meteorological Organization has run out of human for storms in the Atlantic. While individual weather events help to raise awareness, it is the long-term trends that reveal that we are in a climate emergency and on the cusp of the collapse of civilization

According to an October 13 report from the United Nations Office for Disaster Risk Reduction (UNDRR) there have been major increases in the frequency and cost of extreme weather events. These events have  killed 1.23 million and affected more than half of the global population (4.2 billion people). In the last 20 years, there were 7,348 natural disasters worldwide, accounting for nearly $3 trillion in damages. That's almost double the preceding two decades when there were just over 4,200 natural disasters that caused $1.6 trillion in economic losses. The report concluded that the bulk of these disasters were climate-related and it predicted we will see more climate related disasters in the coming years.  If atmospheric emissions are left unchecked the report warned that much of the planet could become an "uninhabitable hell".

The ironic upside of the coronavirus is that it has exposed the fault lines in our civilizations and increased interest in science and fact-based government policy. The one thing that all sensible people understand is that science helps us to understand and respond to the threats that we face.  Scientists have recently added to the body of evidence confirming global warming as the cause of previous extinction events. According to a new study published on October 19 in the international journal Nature Geoscience, in three quarters of all terrestrial life and 95 percent of marine life were wiped out due to greenhouse gases. The so called Permian-Triassic boundary event which took place 252 million years ago was the most extensive mass extinction event in the history of our planet. 

The scientists from Germany, Italy and Canada reconstructed the cascade of events that led to the extinction using geochemical modelling that relied on isotopes in the fossilized shells of clam like organisms called brachiopods. Using the pH in these organisms they created a chronological summary of atmospheric CO2. This led them to conclude that the cause of the extinction was warming and ocean acidification attributable to the release of GHGs from massive volcanic eruptions in Siberia. This resulted in anoxia or large scale oxygen depletion altering elemental cycles.  

The EU study also disproved the theory that the release of methane hydrates was the cause of the Permian-Triassic boundary event, however, another study  published on October 16 in Science Advances, shows how Arctic warming of even a few degrees can accelerate ice melt and release vast amounts of GHGs (methane and CO2). The study examined 27,000 years worth of sediment on the bottom of the Arctic Ocean and concluded that such a surge occurred in the Arctic at the end of the last ice age.  This research revealed that about 14,700 years ago, temperatures in the Arctic suddenly warmed by 1.8 degrees Fahrenheit in an event called the Bölling-Alleröd releasing vast amounts of GHGs. This study has serious implications for Earths systems today. There is about 9 million square miles of permafrost in the Northern Hemisphere and warming could release more carbon than already exists in the Earth's atmosphere triggering a tipping point from which we may not be able to recover. 

As reported by Inside Climate, Merritt Turetsky, director of the Institute of Arctic and Alpine Research at the University of Colorado, Boulder says the study raises grave concerns. "There is momentum in the climate system and also in permafrost thaw trajectories," Turetsky said. "Once permafrost begins to thaw in some settings, a number of self-organizing feedbacks kick in and that means that thaw may continue to occur even if the climate cooled again. We need to aim as a society to keep permafrost carbon in the ground and out of the atmosphere by keeping it frozen," she said.

Human activity has already caused one degree Celsius of warming (1.8 Fahrenheit) globally and 2 degrees Celsius (3.6 Fahrenheit) in the Arctic in the last century and a half. This has led one of the researchers to say "it appears likely that large-scale permafrost thawing and carbon release is going to happen again," lead author Jannik Martens said. "Our study indeed suggests that abrupt permafrost thawing represents a tipping point in the climate system."

Another study published by One Earth on October 15, indicates that climate change drove several species of early humans to extinction. The study combined climate modeling and the fossil record to conclude that temperature changes had existential implications for some of our ancient ancestors. Early species of humans (homo erectus, homo heidelbergensis, and homo neanderthalensis) were unable to adapt despite their complex social organization and the fact that they had despite technological innovations such as clothes, the manipulation of fire, refined stone tools.

PHYORG quotes Dr. Pasquale Raia, a researcher at the Università di Napoli Federico II as saying the inability of our ancestors to cope with climate change is is "worrisome", adding "we found that just when our own species is sawing the branch we're sitting on by causing climate change. I personally take this as a thunderous warning message. Climate change made Homo vulnerable and hapless in the past, and this may just be happening again."

According to yet another study released on September 11 our planet is heading towards "hothouse" conditions not seen in 50 million years. The research examined the Earth's climate swings in the last 66 million-years (Cenozoic era). It did so by studying the fossilized shells of tiny undersea amoebas called forams that were extracted from the ocean floor. The researchers concluded that the current rate of anthropogenic global warming far exceeds the natural climate fluctuations seen at any other point in the Cenozoic era. They also add that this warming could drive temperatures into what they describe as a "hothouse state". This study also revealed that these temperature variations are not causes by the Earth's slowly changing orbit and tilt toward the sun known as Milankovitch cycles. 

Unless we reduce atmospheric emissions we could see temperature increases on a par with the Paleocene-Eocene Thermal Maximum which took place 10 million years after the dinosaur extinction when the temperatures on Earth increased by up to 29 degrees Fahrenheit (16 degrees Celsius) above modern levels. Like our current climate crisis the increase of temperature during this event were driven by a massive release of carbon into the atmosphere.

Not all research is so bleak there is hope in the midst of despair.  A study reported by Science Alert indicates that a sustainable, poverty free future is possible. However, to get there we will need to see sweeping environmental and economic reforms. We will need to deploy technological solutions on a vast scale while massively reducing resource and energy consumption.  However, time is of the essence and as urged by open letter in August we must stop wasting time and act now to prevent the worst impacts of climate change

It is clear that both public and private leaders have thus far failed to do what is necessary and this must change if we are to have any hope of a livable future on this planet.

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