Category: Global Warming

When Ocean Temperatures Dropped 30 Million Years Ago, Some Species Migrated to Warmer Waters; Others Developed New Traits

(p. D2) The Southern Ocean around Antarctica was once warmer. Then about 30 million years ago, the temperature dropped. Few fish could survive temperatures that were just above seawater’s freezing point, and they either migrated to warmer waters or went extinct.

One bottom-dweller held on. Through the power of natural selection, its descendants developed traits that let them survive these unlikely conditions. Today, the Antarctic blackfin icefish, or Chaenocephalus aceratus, thrives in these frigid waters with no scales, blood as clear as water and bones so thin, you can see its brain through its skull.

For the full story see:

JoAnna Klein. “Skullduggery: It’s Not Hard to See How His Brain Works.” The New York Times (Tuesday, March 5, 2019 [sic]): D2.

(Note: the online version of the story has the date Feb. 28, 2019 [sic], and has the title “How the Icefish Got Its Transparent Blood and See-Through Skull.”)

The article quoted above references the following academic article:

Kim, Bo-Mi, Angel Amores, Seunghyun Kang, Do-Hwan Ahn, Jin-Hyoung Kim, Il-Chan Kim, Jun Hyuck Lee, Sung Gu Lee, Hyoungseok Lee, Jungeun Lee, Han-Woo Kim, Thomas Desvignes, Peter Batzel, Jason Sydes, Tom Titus, Catherine A. Wilson, Julian M. Catchen, Wesley C. Warren, Manfred Schartl, H. William Detrich, John H. Postlethwait, and Hyun Park. “Antarctic Blackfin Icefish Genome Reveals Adaptations to Extreme Environments.” Nature Ecology & Evolution 3, no. 3 (March 2019): 469-78.

Repeated Interbreeding of Brown Bears and Polar Bears Illustrates Fuzziness of Defining a Species

(p. D1) Naturalists have been trying for centuries to catalog all of the species on Earth, and the effort remains one of the great unfinished jobs in science. So far, researchers have named about 2.3 million species, but there are millions — perhaps even billions — left to be discovered.

As if this quest isn’t hard enough, biologists cannot agree on what a species is. A 2021 survey found that practicing biologists used 16 different approaches to categorizing species. Any two of the scientists picked at random were overwhelmingly likely to use different ones.

“Everyone uses the term, but no one knows what it is,” said Michal Grabowski, a biologist at the University of Lodz in Poland.

The debate over species is more than an academic pastime. In the current extinction crisis, scientists urgently need to take stock of the world’s biological diversity.

. . .

(p. D4) As scientists gather more genetic data, fresh questions are emerging about what seem, on the surface, to be obviously separate species.

You don’t have to be a mammalogist to understand that polar bears and brown bears are different. Just one look at their white and brown coats will do.

The difference in their colors is the result of their ecological adaptations. White polar bears blend into their Arctic habitats, where they hunt for seals and other prey. Brown bears adapted for life on land further south. The differences are so distinct that paleontologists can distinguish fossils of the two species going back hundreds of thousands of years.

And yet the DNA inside those ancient bones is revealing an astonishing history of interbreeding between polar bears and brown bears. After the two lineages split about half a million years ago, they exchanged DNA for thousands of years. They then became more distinct, but about 120,000 years ago they underwent another extraordinary exchange of genes.

Between 25,000 and 10,000 years ago, the bears interbred in several parts of their range. The exchanges have left a significant imprint on bears today: About 10 percent of the DNA in brown bears comes from polar bears.

Beth Shapiro, a paleogeneticist at the University of California, Santa Cruz, said that the interbreeding most likely occurred when swings in the climate forced polar bears down from the Arctic and into brown bear territory.

For the full story see:

Carl Zimmer. “Defining A Species Is Open To Debate.” The New York Times (Tuesday, February 20, 2024): D1 & D4.

(Note: ellipsis added.)

(Note: the online version of the story has the date February 19, 2024, and has the title “What Is a Species, Anyway?”)

The 2021 survey mentioned above was more fully detailed in:

Stankowski, Sean, and Mark Ravinet. “Quantifying the Use of Species Concepts.” Current Biology 31, no. 9 (May 10, 2021): R428-R429.

Life Was Resilient Even in the Face of Earth’s Greatest Disaster

(p. D2) The asteroid moved 24 times faster than a rifle bullet as it struck Earth some 66 million years ago. Its supersonic shock wave flattened trees across North and South America, and its heat wave sparked incomprehensibly large forest fires.

The event lofted so much debris into the atmosphere that photosynthesis shut down. The non-avian dinosaurs disappeared. And nearly 75 percent of all species were extinguished.

. . .

But even at ground zero, life managed to return, and quickly.

New findings published in the journal Geology . . . [online on January 17, 2020 [sic]] revealed that cyanobacteria — blue-green algae responsible for harmful toxic blooms — moved into the crater a few years after the impact.

For the full story see:

Shannon Hall. “Small Survivors: They Were Left Off Killer Asteroid’s Hit List.” The New York Times (Tuesday, February 18, 2020 [sic]): D2.

(Note: ellipses, and bracketed date, added.)

(Note: the online version of the story has the date Feb. 1, 2020 [sic], and has the title “Asteroid That Killed the Dinosaurs Was Great for Bacteria.” Where the wording differs between the versions, the passages quoted above follow the usually more detailed wording of the online version.)

The findings published in Geology and mentioned above appear in the article:

Schaefer, Bettina, Kliti Grice, Marco J.L. Coolen, Roger E. Summons, Xingqian Cui, Thorsten Bauersachs, Lorenz Schwark, Michael E. Böttcher, Timothy J. Bralower, Shelby L. Lyons, Katherine H. Freeman, Charles S. Cockell, Sean P.S. Gulick, Joanna V. Morgan, Michael T. Whalen, Christopher M. Lowery, and Vivi Vajda. “Microbial Life in the Nascent Chicxulub Crater.” Geology 48, no. 4 (2020): 328-32.

Humans’ Adaptive, Flexible Intelligence Evolved Where Climate “Change Was Dramatic, Frequent, Unpredictable and Stressful”

(p. C9) In “Origins: How Earth’s History Shaped Human History,” astrobiologist and professor of science communication Lewis Dartnell argues that “there is a clear causal chain taking us from the politics and socio-economic conditions of today, to their roots in historical agricultural systems, and then further back to the geological tapestry of the ground beneath our feet.”

. . .

The final sentence he offers as summation—“The Earth made us”—can be read two ways, capturing the parallel themes of “Origins.”

With emphasis on “us,” it refers to the origin of the genus Homo, a clade of naked apes giving rise to our species, H. sapiens, the greatest biological superpower of all time, one so potent that all others in our genus are extinct. Why did this emergence take place in the cradle of the East African Rift and nowhere else? And why did the arrival of our genus broadly coincide with the onset of high-frequency climatic swings about two million years ago? Mr. Dartnell concludes that this recently uplifted and intricately rifted landscape created a mosaic of habitats dominated by lakes that further amplified the climatic oscillations between dry-wet and hot-cool conditions. Change was dramatic, frequent, unpredictable and stressful. Thus “intelligence” became “the evolutionary solution to the problem of an environment that shifts faster than natural selection can adapt the body . . . driving . . . ever more flexible and intelligent behavior.”

For the full review, see:

Robert M. Thorson. “The Earth and Us.” The Wall Street Journal (Saturday, April 23, 2022 [sic]): C9.

(Note: ellipsis between paragraph, added; ellipses within paragraph, in original.)

(Note: the online version of the review has the date May 9, 2019 [sic], and has the title “‘Origins’ Review: The Earth and Us.”)

The book under review is:

Dartnell, Lewis. Origins: How Earth’s History Shaped Human History. New York: Basic Books, 2019.

Low Water Level of Panama Canal Due to El Niño, Not Due to Global Warming

(p. D5) The recent drought in the Panama Canal was driven not by global warming but by below-normal rainfall linked to the natural climate cycle El Niño, an international team of scientists has concluded.

. . .

The scientists found that scant rain, not high temperatures that cause more water to evaporate, was the main reason for low water in the canal’s reservoirs. The weather records suggest that wet-season rainfall in Panama has decreased modestly in recent decades. But the models don’t indicate that human-induced climate change is the driver.

“We’re not sure what is causing that slight drying trend, or whether it’s an anomaly, or some other factor that we haven’t taken into account,” said Clair Barnes, a climate researcher at Imperial College London who worked on the analysis. “Future trends in a warming climate are also uncertain.”

El Niño, by contrast, is much more clearly linked with below-average rainfall in the area, the scientists found. In any given El Niño year, there’s a 5 percent chance that rainfall there will be as low as it was in 2023, they estimated.

For the full story see:

Raymond Zhong. “Study Acquits Global Warming in Drought at Panama Canal.” The New York Times (Thursday, May 2, 2024): A9.

(Note: bracketed date added.)

(Note: the online version of the story has the date May 1, 2024, and has the title “Drought That Snarled Panama Canal Was Linked to El Niño, Study Finds.”)

The report co-authored by Clair Barnes and mentioned above is:

Barnes, Claire, Steve Paton, RF Stallard, H De Lima, B Clarke, M Vahlberg, S Sivanu, A Amakona, K Izquierdo, F Otto, M Zachariah, S Philip, M Mistry, R Singh, and J Arrighi. “Low Water Levels in Panama Canal Due to Increasing Demand Exacerbated by El Niño Event.” In World Weather Attribution Report, May 1, 2024.

Volcanoes Are Proof of Concept That Geoengineering Can Counter Global Warming

(p. C11) ‘Volcanoes get a bad press,” Clive Oppenheimer writes at the beginning of “Mountains of Fire: The Menace, Meaning, and Magic of Volcanoes.”

. . .

Most people know that erupting volcanoes can affect the climate. But there are nuances: “You might expect that volcanoes, with burning flames, spewing molten hot lava and searing ash, would heat up the planet, but in fact they do the opposite.” An addendum, also counterintuitive: “Though several factors . . . influence how much an eruption cools the climate, it is the amount of sulphur blasted into the stratosphere that is critical.”

. . .

. . ., Mr. Oppenheimer’s scientific expertise is what’s most important—for his book and for the rest of us.

For the full review, see:

Howard Schneider. “Explorer of the Underworld.” The Wall Street Journal (Saturday, Oct. 7, 2023): C11.

(Note: ellipses added.)

(Note: the online version of the review has the date October 6, 2023, and has the title “‘Mountains of Fire’ Review: The Vital Volcano.”)

The book under review is:

Oppenheimer, Clive. Mountains of Fire: The Menace, Meaning, and Magic of Volcanoes. Chicago: University of Chicago Press, 2023.

In Australia and Japan “Coral Appear to Be Migrating Poleward”

(p. A9) Scientists are still learning about corals’ ability to adapt to climate change. Efforts are underway to breed coral that tolerate higher temperatures. In a few places, including Australia and Japan, coral appear to be migrating poleward, beginning to occupy new places.

For the full story see:

Catrin Einhorn. “Scientists Say Rising Ocean Temperatures Are Damaging Coral Reefs Around the World.” The New York Times (Tuesday, April 16, 2024): A9.

(Note: the online version of the story has the date April 15, 2024, and has the title “The Widest-Ever Global Coral Crisis Will Hit Within Weeks, Scientists Say.”)

Too Little Carbon Dioxide Caused Earth to Be a Frigid Barren “Snowball” for 56 Million Years

(p. D4) Around 717 million years ago, Earth’s humid landscapes and roiling blue waters transformed into a frigid, barren world. Scientists nicknamed this stage of geological history, and others like it, Snowball Earth.

What exactly froze the planet nearly solid has been a mystery, as has how it remained that way for 56 million years. On Wednesday, a team of researchers at the University of Sydney said they have it figured out. Earth’s glaciation, they say, may have come from a global drop in carbon dioxide emissions, a result of fewer volcanoes expelling the gas into the atmosphere.

Less carbon dioxide makes it more difficult for Earth’s atmosphere to trap heat. If the depletion were extreme enough, they argued, it could have thrust the planet into its longest ice age yet.

The theory, published in the journal Geology, adds insight to the way geological processes influenced Earth’s past climate. It may also help scientists better understand trends in our current climate.

. . .

Dr. Dutkiewicz and her colleagues turned their eyes to volcanoes because of a newly available model of Earth’s shifting tectonic plates. As the continents spread apart, they studied the changing length of the mid-ocean ridge — a chain of underwater volcanoes — predicted by the model.

The team then calculated the amount of volcanic gas emissions at the beginning of, and throughout, the ice age. Their results showed a drop in atmospheric carbon dioxide sufficient to initiate and sustain a 56-million-year glaciation.

A reduction in volcanic gas emissions has been proposed as an explanation for Snowball Earth before. But according to Dr. Dutkiewicz, this is the first time researchers have proved that the mechanism was viable through modeled computations.

For the full commentary, see:

Katrina Miller. “How Earth Stayed Frozen for So Long.” The New York Times (Tuesday, February 13, 2024): D4.

(Note: ellipsis added.)

(Note: the online version of the commentary was updated February 12, 2024, and has the title “How Earth Might Have Turned Into a Snowball.”)

The paper in the journal Geology mentioned above is:

Dutkiewicz, Adriana, Andrew S. Merdith, Alan S. Collins, Ben Mather, Lauren Ilano, Sabin Zahirovic, and R. Dietmar Müller. “Duration of Sturtian “Snowball Earth” Glaciation Linked to Exceptionally Low Mid-Ocean Ridge Outgassing.” Geology 52, no. 4 (2024): 292-96.

Carbon Dioxide Greens the Earth as Plants Slow Global Warming

(p. D3) For decades, scientists have been trying to figure out what all the carbon dioxide we have been putting into the atmosphere has been doing to plants. It turns out that the best place to find an answer is where no plants can survive: the icy wastes of Antarctica.

As ice forms in Antarctica, it traps air bubbles. For thousands of years, they have preserved samples of the atmosphere. The levels of one chemical in that mix reveal the global growth of plants at any point in that history.

“It’s the whole Earth — it’s every plant,” said J. Elliott Campbell of the University of California, Merced.

Analyzing the ice, Dr. Campbell and his colleagues have discovered that in the last century, plants have been growing at a rate far faster than at any other time in the last 54,000 years. Writing in the journal Nature, they report that plants are converting 31 percent more carbon dioxide into organic matter than they were before the Industrial Revolution.

. . .

Since plants depend on carbon dioxide to grow, scientists have long wondered if that extra gas might fertilize them.

. . .

In the mid-2000s, atmospheric scientists discovered a powerful new way to measure plant growth: by studying an unimaginably rare molecule called carbonyl sulfide.

Carbonyl sulfide — a molecule made of a carbon atom, a sulfur atom and an oxygen atom — is present only in a few hundred parts per trillion in the atmosphere. That is about a million times lower than the concentration of carbon dioxide. Decaying organic matter in the ocean produces carbonyl sulfide, a gas that then floats into the atmosphere.

Plants draw in carbonyl sulfide along with carbon dioxide. As soon as it enters their tissues, they destroy it. As a result, the level of carbonyl sulfide in the air drops as plants grow.

. . .

But Dr. Campbell and his colleagues found that it hasn’t increased very much. As we have been adding carbonyl sulfide to the atmosphere, plants have been pulling it out. In fact, the scientists found, they have been pulling it out at a staggering rate.

“The pace of change in photosynthesis is unprecedented in the 54,000-year record,” Dr. Campbell said. While photosynthesis increased at the end of the ice age, he said, the current rate is 136 times as fast.

With all that extra carbon dioxide going into plants, there has been less in the air to contribute to global warming. The planet has warmed nearly 2 degrees Fahrenheit since 1880, but it might be even hotter if not for the greening of the Earth.

For the full commentary, see:

Carl Zimmer. “MATTER; A Global Greening.” The New York Times (Tuesday, April 11, 2017 [sic]): D3.

(Note: ellipses added.)

(Note: the online version of the commentary has the date April 5, 2017 [sic], and has the title “MATTER; Antarctic Ice Reveals Earth’s Accelerating Plant Growth.”)

The paper in Nature mentioned above is:

Campbell, J. E., J. A. Berry, U. Seibt, S. J. Smith, S. A. Montzka, T. Launois, S. Belviso, L. Bopp, and M. Laine. “Large Historical Growth in Global Terrestrial Gross Primary Production.” Nature 544, no. 7648 (April 16, 2017 [sic]): 84-87.

Musk Calls German Anti-Electric-Vehicle Ecoactivists “Dumber Than a Doorstop”

(p. B1) GRÜNHEIDE, Germany—When Tesla opened its first full-scale European factory in this sleepy community outside of Berlin, Elon Musk was feted as a hero, the chancellor gave a speech and workers cheered the rollout of new Model Ys.

On Wednesday [March 13, 2024], almost two years to the day later, Musk was back, this time to cheer up workers after an act of sabotage by suspected eco-activists shut down the plant for more than a week.

. . .

Tesla didn’t respond to requests for comment on the various incidents. In a post on his X social-media platform, Musk has called the eco-activists “dumber than a doorstop” for their criticism of electric vehicles.

As the plant’s managers and workers gathered in a tent on the factory grounds for a “team huddle” on Wednesday, Musk could be seen carrying his son. Hoisting the boy onto his shoulders amid calls of “Elon, Elon,” he shouted back: “They can’t stop us!” and “Ich liebe Dich!”—German for “I love you.”

As he left, reporters asked him whether he was still committed to expanding the plant and producing vehicles in Germany.

“Yes, absolutely,” he said. “Germany rocks!”

For the full story, see:

William Boston. “Tesla Faces Blowback in Germany.” The Wall Street Journal (Friday, March 15, 2024): B1-B2.

(Note: ellipses, and bracketed date, added.)

(Note: the online version of the story has the date March 14, 2024, and has the title “Elon Musk’s Plans to Conquer Europe Collide With Germany’s Culture Wars.”)

As Temps Rise, Trees Adapt to Global Warming by Slowing Their Increasing Release of Carbon Dioxide

The late great physicist Freeman Dyson was courageously skeptical of global warming based on forces that move Earth back toward equilibrium when initially nudged away. The story quoted below provides evidence consistent with Dyson’s narrative.

(p. D2) The bend-don’t-break adaptability of trees extends to handling climate change, according to a new study that says forests may be able to deal with hotter temperatures and contribute less carbon dioxide to the atmosphere than scientists previously thought.

In addition to taking in carbon dioxide during photosynthesis, plants also release it through a process called respiration. Globally, plant respiration contributes six times as much carbon dioxide to the atmosphere as fossil fuel emissions, much of which is reabsorbed by plants, the oceans and other elements of nature. Until now, most scientists have thought that a warming planet would cause plants to release more carbon dioxide into the atmosphere, which in turn would cause more warming.

But in a study published Wednesday [March 16, 2016 [sic]] in Nature, scientists showed that plants were able to adapt their respiration to increases in temperature over long periods of time, releasing only 5 percent more carbon dioxide than they did under normal conditions.

Based on measurements of short-term temperature responses in this study and others, the scientists expected that the plants would increase their respiration by nearly five times that much.

At two forest-research sites in Minnesota, scientists tested how the respiration rates of 10 different species of trees — from boreal and temperate forests — were affected by increases in temperature over a period of three to five years, using heating cables to warm some of the trees.

The trees were monitored in two conditions: ambient, and about 6 degrees warmer than that.

To demonstrate how the plants adapted to long-term temperature increases, the scientists compared three things: how much carbon dioxide the trees released in ambient conditions; how much the trees released in the warmer conditions; and how much carbon dioxide the trees released when they were exposed to the warmer temperature for a short period of time (minutes or hours).

When the scientists compared the results, they found that the trees that were acclimated to the warmer temperatures increased their carbon dioxide release by a much smaller amount than the trees that were only exposed to a short-term temperature increase of the same magnitude.

Boreal and temperate forests account for a third of the world’s forest areas. If they are able to adapt respiration rates as this study suggests, the planet will breathe easier.

The source of the story is:

Tatiana Schlossberg. “Energy Appetite in U.S. Endangers Goals on Climate.” The New York Times (Tuesday, March 22, 2016 [sic]): D2.

(Note: bracketed date added.)

(Note: the online version of the story was updated March 16, 2016 [sic], and has the title “Trees Deal With Climate Change Better Than Expected.” The last two sentences quoted above differ in a non-trivial way in the print and the online versions. Above I choose to quote the less politically correct print version. The wimpish politically correct online version is: “Boreal and temperate forests account for a third of the world’s forest areas, and if they adapt their respiration rates in the way this study suggests, the forests, the planet’s lungs, can breathe easy.”)

The Nature article mentioned above is:

Reich, Peter B., Kerrie M. Sendall, Artur Stefanski, Xiaorong Wei, Roy L. Rich, and Rebecca A. Montgomery. “Boreal and Temperate Trees Show Strong Acclimation of Respiration to Warming.” Nature 531, no. 7596 (March 16, 2016): 633-36.