Current climate alarmist fervor can be wholly undermined by the magnitude of change for the Antarctic ice sheet in recent decades.

It’s IPCC AR6 Day (10 August, 2021) – a day devoted to celebratory alarmism. Here’s the larger perspective.

The most concerning aspect of global warming is often identified as the threat of rising sea waters engulfing the globe’s heavily populated coasts, displacing 100s of millions of people.

Back in 1989, when the UN was busily preparing for the release of the first humans-cause-catastrophic-global-warming report the following year, the prevailing alarmist view was that humans can control and “solve” the Earth’s greenhouse effect (Associated Press, 1989). The outlook was bleak, as “entire nations could be wiped off the face of the Earth by rising sea levels if the global warming trend is not reversed by the year 2000.” In other words, “governments have a 10-year window of opportunity to solve the greenhouse effect [1999] before it goes beyond human control.”

Image Source: Associated Press, 1989

To put sea level rise alarmism into perspective, scientists note it would take “prolonged periods lasting hundreds of thousands to millions of years to even induce partial retreat” for the Antarctic ice sheet (Nature Geoscience, 2018)

Image Source: Nature Geoscience, 2018

The 2007 IPCC report indicated a warming Antarctica would lead to net mass gains and a reduction in sea levels.

We’ve recently learned that “profound” cooling has been occurring for East Antarctica since the 1970s, and cooling (-1.68°C since 1979) has also extended to West Antarctica.

And now a new study indicates Antarctica contributed just 0.76 of a centimeter to sea level rise from 1992-2017, or 0.3 of a millimeter per year. Also, comparing 1997-2008 to 2009-2018, there has been a net advance in the ice extent for Antarctica in the more recent decade.

Southern Ocean surface temperatures have uncertainly cooled -0.5°C along East Antarctica and warmed 0.5°C along West Antarctica and the Peninsula in the last 2 decades.

None of these trends support an alarmist world view of the current state of climate.

Image Source: Baumhoer et al., 2021

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August 9, 2021