What You Need to Know about the Forthcoming Climate Change Report

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What You Need to Know about the Forthcoming Climate Change Report
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What You Need to Know about the Forthcoming Climate Change Report

Talk about management by committee: one group of more than 800 scientist authors to cope with more than 9,000 scientific publications on climate change and more than 20,000 comments from “expert reviewers” (plus another 30,000 or so from various other interested parties.) Now the Intergovernmental Panel on Climate Change is into four days of wrangling in Stockholm between scientists and governments over the wording of a warning on climate change that we’ve all heard before.

They will literally go over it line by line, with countries like Russia asking that plans for gargantuan mitigation projects like geoengineering be included somehow and countries like Saudi Arabia wondering whether climate change is such a big deal after all. Because, you know, the “ hiatus,” or “ pause,” or whatever you want to call it.

Of course, said plateau in the upward trajectory of average global surface temperatures says nothing about the fundamental physics that involves molecules of carbon dioxide and other greenhouse gases trapping ever more heat within the Earth’s atmosphere and oceans. Nothing has fundamentally changed since the first assessment in 1990 concluded: “emissions resulting from human activities are substantially increasing atmospheric concentrations of greenhouse gases… These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface.”

In other words, thank the vast Pacific Ocean (particularly perhaps its watery deeps) for keeping climate change from accelerating out of control and watch out for the next El Nino, which could well trigger a major uptick in the global thermometer. Or, as IPCC co-chair Qin Dahe of China put it in a press release: “The scientific evidence for anthropogenic climate change has strengthened year by year, leaving fewer uncertainties about the serious consequences of inaction, despite the fact that there remain knowledge gaps and uncertainties in some areas of climate science.” Ahem, clouds (though the most recent science suggests, on balance, clouds are likely to contribute more warming than cooling), aerosols, etc. Yes, uncertainty reigns, but safe is better than sorry. Most of us buy fire insurance after all.

So here’s the preview:

(1) We’re responsible. Period. And CO2 is the main greenhouse gas.

(2) Effects of climate change, like the meltdown of Arctic sea ice or sea level rise, are happening faster than anticipated (in previous IPCC reports, notoriously conservative.)

(3) Ocean acidification continues apace and could end up being the long-term legacy of greenhouse gas emissions from fossil fuel-burning and forest-clearing.

(4) The global warming of surface temperatures has just as good a chance of being not that bad (another 1 degree Celsius by 2100) as terrifyingly bad (plus 4 degrees C this century) with something in the middle most likely.

(5) No matter what we do tomorrow, the greenhouse gases already in the atmosphere will be changing the climate for centuries to come. So get ready to adapt.

The real question is (and always has been): is any of that enough to prompt action? Concentrations of greenhouse gases in the atmosphere touched 400 parts-per-million for the first time in human history this past May, after all. Regardless, watch this website for more throughout the week and in the turbulent decades to come.

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