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biology+acidification, climate-debate

Past global photosynthesis reacted quickly to more carbon in the air

by University of Copenhagen, Mar 10, 2022 in ScienceDaily

Ice cores allow climate researchers to look 800,000 years back in time: atmospheric carbon acts as fertilizer, increasing biological production. The mechanism removes carbon from the air and thereby dampens the acceleration in global warming.

Even under ice age conditions will plants, plankton, and other life forms be able to increase production whenever atmospheric carbon concentrations rise. The mechanism will not prevent an ongoing trend of global warming, but at least dampen the acceleration. This conclusion stems from an international collaboration involving the Physics of Ice Climate Earth (PICE) center of Niels Bohr Institute, University of Copenhagen.

“Global biosphere production through photosynthesis is the strongest absorbing flux of atmospheric carbon dioxide. It is therefore essential to understand its natural variability for a better projection of the future carbon cycle,” says Postdoc researcher Ji-Woong Yang, PICE, continuing:

“Nowadays, as we have Earth observation satellites and other advanced equipment, the mechanism of carbon fertilization is well established. However, we were not sure that the same mechanism existed in past periods where the climate was very different and atmospheric carbon concentrations much lower. The new results confirm the existence of the strong correlation and allow us to model future developments with more confidence.”

Eight glacial cycles are covered

In collaboration with Laboratoire des Science du Climat et de l’Environnement, France, the PICE team has studied the ancient air trapped inside tiny air bubbles in an Antarctic ice core. The ice core represents the last 800,000 years of climatic development.

The scientists take advantage of the fact that the oxygen atom does not only exist in the most common form 16O with 8 protons and 8 neutrons but also as the isotopes 17O and 18O. The isotopic composition is a tracer for biosphere productivity. Uniquely, the method will show the global level of biological production in contrast to other methods which give more localized results.

Combining the air bubble measurements with modeling of oxygen behavior in both the biosphere and the stratosphere, the researchers were able to quantify the biosphere productivity evolution under both glacial periods (ice ages) and interglacial periods. In total, eight glacial cycles were covered.

“The results clearly demonstrate that productivity drops during glacial periods and increases during interglacial periods. Further, a strong correlation exists with past atmospheric carbon dioxide concentrations measured from multiple ice cores. In addition, the effect is more prominent during glacial periods where the level of carbon dioxide and the global biosphere productivity start to increase several thousand years before the ice caps begin to melt. This correlation is explained by the strong fertilization effect by atmospheric carbon dioxide,” says Ji-Woong Yang.

climate-debate

There is no climate crisis

by R. Darwall, Mar 7, 2022 in TheSpectator

“No climate crisis” is, of course, not the spin the Intergovernmental Panel on Climate Change (IPCC) is putting on its new 3,676-page report released last month. “The choices we make in the next decade will determine our future,” the IPCC says. “Any further delay in concerted global action will miss a brief and rapidly closing window to secure a liveable future.”

It could hardly be plainer. The report is political advocacy barely masquerading as science.

The IPCC Working Group II report is not meant to be about policy; that’s the job of Working Group III, which has yet to produce its contribution to the sixth assessment report. “The focus of our new report is on solutions,” the IPCC says of the Working Group II report. “It highlights the importance of fundamental changes in society.” The solution to climate change, the IPCC claims, is renewable energy, circular economies, healthy diets, universal health coverage and social protection. The only surprise is that the IPCC didn’t include abolishing the Second Amendment in its climate catechism.

“Scientific evidence shows that addressing the risks and impacts of climate change successfully involves a more a diverse set of actors than previously thought” and involvespartnerships with “traditionally marginalized groups, including women, youth, Indigenous Peoples, local communities and ethnic minorities (high confidence).” How on earth did the IPCC exclude the LBGTQ+ community? “Different interests, values and worldviews can be reconciled if everyone works together,” the IPCC says. This isn’t science. It’s climate kumbaya.

Small islands were the poster child of net zero as they claimed they risked sinking beneath the waves thanks to rising sea levels. They successfully lobbied for the adoption of the target in the Paris climate agreement to limit the increase in global temperature to 1.5 degrees Celsius above pre-industrial levels. The IPCC therefore includes them in a list of global hotspots of high human vulnerability, asserting that their vulnerability will increase in the context of sea level rise. Yet only four years ago, the IPCC in its 1.5 degree Celsius special report stated that “observations, models and other evidence” indicate that unconstrained Pacific atolls have kept pace with sea level rises and that there had been “little reduction in size or net gain in land.”

In a blog post, Roger Pielke Jr. of the department of environmental studies at the University of Colorado Boulder notes that the IPCC lifts projections of future climate damages from studies that eliminate the choice of adapting to climate change, a practice Pielke calls “misleading at best.” Yet buried in the report is a study showing that adequate flood protection, i.e. adaptation, could avoid 95 percent of projected flood damages.

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better to know...?, climate-debate

Thawing Permafrost Could Leach Microbes, Chemicals Into Environment

by C. Rotter, Mar 10, 2022 in WUWT

Scientists are turning to a combination of data collected from the air, land, and space to get a more complete picture of how climate change is affecting the planet’s frozen regions.

Trapped within Earth’s permafrost – ground that remains frozen for a minimum of two years – are untold quantities of greenhouse gases, microbes, and chemicals, including the now-banned pesticide DDT. As the planet warms, permafrost is thawing at an increasing rate, and scientists face a host of uncertainties when trying to determine the potential effects of the thaw.

A paper published earlier this year in the journal Nature Reviews Earth & Environment looked at the current state of permafrost research. Along with highlighting conclusions about permafrost thaw, the paper focuses on how researchers are seeking to address the questions surrounding it.

Infrastructure is already affected: Thawing permafrost has led to giant sinkholes, slumping telephone poles, damaged roads and runways, and toppled trees. More difficult to see is what has been trapped in permafrost’s mix of soil, ice, and dead organic matter. Research has looked at how chemicals like DDT and microbes – some of which have been frozen for thousands, if not millions, of years – could be released from thawing permafrost.

Then there is thawing permafrost’s effect on the planet’s carbon: Arctic permafrost alone holds an estimated 1,700 billion metric tons of carbon, including methane and carbon dioxide. That’s roughly 51 times the amount of carbon the world released as fossil fuel emissions in 2019. Plant matter frozen in permafrost doesn’t decay, but when permafrost thaws, microbes within the dead plant material start to break the matter down, releasing carbon into the atmosphere.

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better to know...?, climate-debate

Sulfur emissions from consumption by developed and developing countries produce comparable climate impacts

by J. Lin et al., Feb 17, 2022 in Nature

Abstract

Regional consumption activities supported by domestic production and international trade have led to substantial aerosol-related emissions worldwide. Here we quantify sulfur dioxide emissions associated with consumption by developed and developing countries and assess the resulting climate impacts using an Earth system model. We find that although the consumption-associated emissions of developed countries are 40% less than those of developing countries, they lead to similar impacts on global mean surface air temperature and precipitation. This is because the effective radiative forcing induced per emission is greater for developed countries, which we attribute to the emissions being located at higher northern latitudes and being more evenly distributed zonally. Emissions from developing countries have a greater impact on temperature and precipitation over the tropical monsoon regions of China and India. Our results demonstrate the importance of trade and emission region in determining how consumption translates into global climate impact.