Maun Loa Observatory - 4/9/20 - Highest Atmospheric Daily CO2 Reading On Record - 417.91 ppm

[hatrack]

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[LonePirate]

1. It is interesting how this reading is at a record given how much of the world economy is shut down.

[Maraya1969]

2. I don't understand this. Care to offer an explanation?

[hatrack]

4. Part of it is seasonal - annual atmospheric CO2 content peaks in May, and bottoms out in October

Part of it is that what's already up there - that is, the CO2 that's producing the warming we've already seen - is what we emitted 20, 30, 50 years ago.

Carbon dioxide hangs around in the atmosphere for about 100 years before natural processes (absorption in plants or in the ocean, notably) can dispose of it. And, as the oceans lose their ability to absorb more, and as more and more forests burn and are cut down, that "sponge" grows smaller and less effective.

In addition, though the Industrial Revolution was up and running a good 250-275 years ago (depending on when you officially start), we haven't gotten really good at producing CO2 as a byproduct of industrial civilizatio until the last few decades. Half of all the CO2 emitted by China, for example, has been produced since 2005.

Finally, through natural processes - for example, as permafrost melts (aka thermokarsting) - lots and lots of carbon is released from previously frozen soils. Huge fires in places like Siberia and Australia also help.

Compared to all of the above, relatively small, relatively recent cuts in economic activity don't add up to a large-scale reductions (though pollution reductions are certainly beneficial).

[progree]

3. We're emitting CO2 into the atmosphere faster than it can be absorbed. The only possible result:

the CO2 concentration goes up.

Last month's modestly reduced levels are still more than can be absorbed in a month.