Guest essay by Eric Worrall
According to a new study there’s no longer any point trying to prevent global warming from exceeding United Nations goals of 1.5C or even 2C – though we should cease CO2 emissions immediately to slow it down.
Global Warming Already Baked In Will Blow Past Climate Goals, a New Study Says
BY SETH BORENSTEIN / AP JANUARY 4, 2021 11:23 PM EST
The amount of baked-in global warming, from carbon pollution already in the air, is enough to blow past international agreed upon goals to limit climate change, a new study finds.
But it’s not game over because, while that amount of warming may be inevitable, it can be delayed for centuries if the world quickly stops emitting extra greenhouse gases from the burning of coal, oil and natural gas, the study’s authors say.
For decades, scientists have talked about so-called “committed warming” or the increase in future temperature based on past carbon dioxide emissions that stay in the atmosphere for well over a century. It’s like the distance a speeding car travels after the brakes are applied.
But Monday’s study in the journal Nature Climate Change calculates that a bit differently and now figures the carbon pollution already put in the air will push global temperatures to about 2.3 degrees Celsius (4.1 degrees Fahrenheit) of warming since pre-industrial times.
Just because the world is bound to get more warming than international goals, that doesn’t mean all is lost in the fight against global warming, said Dessler, who cautioned against what he called “climate doomers.”
The abstract of the study;
Greater committed warming after accounting for the pattern effect
Our planet’s energy balance is sensitive to spatial inhomogeneities in sea surface temperature and sea ice changes, but this is typically ignored in climate projections. Here, we show the energy budget during recent decades can be closed by combining changes in effective radiative forcing, linear radiative damping and this pattern effect. The pattern effect is of comparable magnitude but opposite sign to Earth’s net energy imbalance in the 2000s, indicating its importance when predicting the future climate on the basis of observations. After the pattern effect is accounted for, the best-estimate value of committed global warming at present-day forcing rises from 1.31 K (0.99–2.33 K, 5th–95th percentile) to over 2 K, and committed warming in 2100 with constant long-lived forcing increases from 1.32 K (0.94–2.03 K) to over 1.5 K, although the magnitude is sensitive to sea surface temperature dataset. Further constraints on the pattern effect are needed to reduce climate projection uncertainty.
Read more (paywalled): https://www.nature.com/articles/s41558-020-00955-x
Sadly the full study is paywalled, but I think we get the idea.
I’ve got to say I’m a little disappointed. How much longer do we have to wait until there is no longer any hope, and greens give up on urging us to build renewables? I had hoped that once greens came to believe global warming was on track to blow through 2C they’d declare game over. But they’re still finding reasons to demand compliance.
via Watts Up With That?
January 5, 2021 at 04:55PM