I wonder if we even see a CO2 related Covid signal in temperatures.
That last fall (or slowdown) of CO2 growth was after the housing/banking crisis but is there any paper that works out a temp change from that slowdown?
The deceiving thing about the big, historic drop in CO2 emissions
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This is all likely true. We’re headed for some major emission declines. But, critically, the true number global warming cares about — the amount of carbon dioxide saturating the atmosphere — will barely be impacted by an unprecedented drop in carbon emissions this year, a drop the International Energy Agency estimates at nearly eight percent (compared with historic 2019 levels).
That’s because atmospheric CO2 levels are like a massive bank account that’s been accruing more and more carbon every year for well over a century (this bank account is now at its highest levels in at least 800,000 years, but more likely millions of years). This year’s carbon emissions, however, are just a deposit. This 2020 deposit may be smaller than in 2019, but it’ll still add to the atmospheric CO2 bank account.
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“We’re still emitting 92 percent of a very, very large number,” said Kristopher Karnauskas, a climate scientist at the University of Colorado Boulder.
This means, by year’s end, we’ll be puffing about the same amount of carbon into the atmosphere as we were in 2010. Yes, we’ll still be adding over 30 gigatonnes — or 30 billion metric tons — of CO2 to the atmosphere this year.
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To illustrate, before the pandemic and ensuing economic shock, Earth’s average atmospheric CO2 concentration was expected to average around 414.2 parts per million, or ppm, this year. With a five percent drop in emissions, this would fall to just 414.0 ppm, explained Hausfather. And with an eight percent emissions reduction, it would drop slightly more to around 413.9 ppm. Importantly, this is still much higher than average CO2 concentrations last year, which averaged 411.5 ppm.
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“It’s only transportation that has changed radically,” explained Rob Jackson, a professor of earth system science at Stanford University and director of the Global Carbon Project, which researches carbon emissions. “Outside of transportation, emissions are not changing all that much,” he said. For example, we’re still using lots of electricity at home.
https://mashable.com/article/carbon-emissions-drop-2020-coronavirusThe easier detected changes are related to aerosol reductions.
1) There was already going to be an effect from ´cleaner´ shipping fuels. This effect much be much stronger with less shipping overall.
But IIRC the effect is quite local so reduction in Atlantic shipping might be more important then reduction in ships going from China to the US via the Pacific ocean?
2) Then there is a reduction from factories closing temporarily but i have seen no good breakdowns of these.
And maybe
3) Clearer skies. They have been quite remarkable in the Netherlands although the weather has ruined it this week. Then again that might not do that much see:
https://www.int-res.com/articles/cr2004/26/c026p001.pdf