THIS POST IS A STUDY OF A SOIL SCIENCE REVOLUTION THAT HAS CLIMATE CHANGE IMPLICATIONS

LINK TO SOURCE: https://www.quantamagazine.org/a-soil-science-revolution-upends-plans-to-fight-climate-change-20210727/

PART-1: WHAT THE SOURCE DOCUMENT SAYS

A Soil-Science Revolution Upends Plans to Fight Climate Change

A centuries-old concept in soil science has recently been thrown out. Yet it remains a key ingredient in everything from climate models to advanced carbon-capture projects. One teaspoon of healthy soil contains more bacteria, fungi and other microbes than there are humans on Earth. Those hungry organisms can make soil a difficult place to store carbon over long periods of time. The hope was that the soil might save us with civilization pumping ever-increasing amounts of carbon dioxide into the atmosphere. Plants are nature’s carbon scrubbers and we had hoped that they would remove the excess carbon and bury it underground. Researchers at the Salk Institute had hoped to bioengineer plants whose roots would capture carbon from the atmosphere and convert them to suberin. Even after the plant dies, the carbon in the suberin stays buried for centuries. This Harnessing Plants Initiative is the brightest star in a crowded firmament of climate change solutions based on the brown stuff beneath our feet. Such plans depend critically on the existence of large, stable, carbon-rich molecules that can last hundreds or thousands of years underground. Such molecules, collectively called humus, have long been a keystone of soil science; major agricultural practices and sophisticated climate models are built on them. But over the past 10 years or so, soil science has undergone a quiet revolution, akin to what would happen if, in physics, relativity or quantum mechanics were overthrown. Except in this case, almost nobody has heard about it including many who hope soils can rescue the climate. “There are a lot of people who are interested in sequestration who haven’t caught up yet. A new generation of soil studies powered by modern microscopes and imaging technologies has revealed that whatever humus is, it is not the long-lasting substance scientists believed it to be. Soil researchers have concluded that even the largest, most complex molecules can be quickly devoured by soil’s abundant and voracious microbes. The magic molecule you can just stick in the soil and expect to stay there may not exist. The consequences go far beyond carbon sequestration strategies. Major climate models such as those produced by the Intergovernmental Panel on Climate Change are based on this outdated understanding of soil. Several recent studies indicate that those models are underestimating the total amount of carbon that will be released from soil in a warming climate. Computer models that predict the greenhouse gas impacts of farming practices are probably overly optimistic about soil’s ability to trap and hold on to carbon.

PART-2: CRITICAL COMMENTARY

IN A RELATED POST: LINK: https://tambonthongchai.com/2020/06/19/vegandiet/ WE PRESENT THE CASE THAT THE THEORY OF ANTHROPOGENIC GLOBAL WARMING BY WAY OF THE INDUSTRIAL ECONOMY THAT GOT STARTED ONLY WHEN THE INDUSTRIAL REVOLUTION HAD STARTED IS VERY SPECIFICALLY A FOSSIL FUEL ISSUE. IT IS NOT A CARBON CYCLE ISSUE. THE ONLY PART OF THE PAPER ABOVE THAT IS RELEVANT TO THIS UNDERSTANDING OF AGW THEORY IS THAT FUTURE WARMING AT A SUFFICIENTLY HIGH TEMPERATURE MAY CAUSE FEEDBACK CO2 EMISSIONS FROM THE SOIL; BUT THIS PAPER IS IRRELEVANT IN THE CONTEXT OF CLIMATE ACTION. REGARDLESS OF THE BEHAVIOR OF CARBON DIOXIDE IN SOILS, WE CAN MEASURE FOSSIL FUEL EMISSIONS AND WE CAN MEASURE INCREASES IN ATMOSPHERIC CO2 CONCENTRATION AND WE FIND THAT THE DATA ARE CONSISTENT WITH THE CLIMATE SCIENCE ASSUMPTION THAT THE AIRBORNE FRACTION IS 50% OF EMISSIONS. THERE ARE SOME UNCERTAINTIES IN THIS ISSUE WHERE THE AIRBORNE FRACTION VARIES SLIGHTLY YEAR TO YEAR AND THE CO2 SEQUESTRATION DYNAMICS OF THE SOIL MAY PLAY A ROLE IN THAT VARIANCE, BUT THE ABILITY OF THE SOIL TO SEQUESTER CO2 IS NOT A GLOBAL WARMING ISSUE.

IN OTHER WORDS, THE CARBON SEQUESTRATION FUNCTION OF THE SOIL IS A CARBON CYCLE ISSUE. IT IS NEITHER A GLOBAL WARMING ISSUE NOR A CLIMATE ACTION ISSUE.