March 2020 Atmospheric CO2 Content: 414.50 ppm; March 2019 411.97 ppm; March 2018 409.41 ppm

[hatrack]

https://www.esrl.noaa.gov/gmd/ccgg/trends/

[lapfog_1]

1. If humans vanished, the planet would likely repair itself.

[in2herbs]

2. With less air, vehicle traffic because of COVID I don't understand why the numbers did not go down.

[hatrack]

3. Releases of carbon from natural sources continue, seasonal cycle, still lots of industry running

. . . failing carbon uptake from the planet's oceans, deforestation, power generation and so forth.

If nothing else, this should be instructive - even when things are crashing to a halt (at least from our perspective) the enormous momentum produced by 250 years of industrialization will continue.

[in2herbs]

4. Thank you. This helps my understanding and global warming commitment.

[hatrack]

5. Also, the Keeling Curve (seasonality) . . .

What Dave Keeling discovered back in the late 1950s is that the Earth "breathes" in and out seasonally.

CO2 rises and falls in synch with the vegetation cycle in the Northern Hemisphere, where the overwhelming majority of land (and plants) are. We're approaching the peak for 2020, likely mid-May, with the annual low coming in October.

Apologies if you're already familiar with this!

https://www.climate.gov/news-features/videos/keeling-curve-carbon-dioxide-levels-becomes-chemical-landmark

[in2herbs]

6. No, I wasn't familiar with that either. I've spent most of my life outside, about 8-10 or more

hours every day so I am informed mostly by the changes I witness in nature not with what I read, but I accept without hesitation the opinions of scientists who rely on science. I'll check out the link. Thanks again.

[Finishline42]

7. thanks but...

If you look back at the data from 2007-09, does it show a drop in CO2 levels (or at least a pause) beyond the seasonal fluctuations?

Because if not, isn't it logical to assume that what's creating the additional CO2 is more than just our input?

BTW, I am a firm believer in climate change. I think it's mostly about scale - 750 mil pop in 1750 - dawn of industrial age to 10 times that today x 100 more energy use per person (plug in your own number but it's multiples of what energy was being used in 1750).

[hatrack]

8. On balance, no. Naturally there are variations (monthly and annual) . . .

An occasional flat YOY change (early 1960s, IIRC). But the overall trajectory is upwards, year after year.

We also know that it's us because of carbon isotope balances.

Since coal, oil and gas contain no Carbon 14, burning lots and lots of fossil fuels means that over time, the amount of Carbon 14 in the atmosphere has declined as the amount of Carbon 12 has risen.

NOAA does a better job on this than I do! More cool science below:

https://www.esrl.noaa.gov/gmd/outreach/isotopes/mixing.html