Keeling Curve – Greg Laden's Blog

Spike in Greenhouse Gasses

Greg Laden — Wed, 16 Aug 2017 18:51:57 +0000

Greenhouse gases go up and down in three ways.

First, there is the annual up and down cycle that happens because there is more land in the Northern Hemisphere. I won’t explain that to you now because I know you can figure out why that happens.

Second, there is natural variation up and down aside from that annual cycle that has to do with things like volcanoes and such. This includes the rate of forest fires, which increase greenhouse gases by turning some of the Carbon trapped in plant tissue into gas form as CO2. (That was a hint for the answer to the first reason!)

Third, humans.

There was a big spike in CO2 concentration this year, and it was caused by El Nino increasing forest fire output, which in turn, freed up some of that CO2. Also, regional drought in some places simply slowed down plant growth, leaving some Carbon stranded in the atmosphere.

So was that natural? Not at all. ENSO cycles, that cause El Nino and La Nina constitute and oscillation in rainfall patterns, and part of that results in extra forest fires or other effects as mentioned. But these effects are caused directly by weather disruption. Human caused global warming was already doing that. The severe El Nino of 2014-2016 was more severe (and probably longer) than any, or almost any, ever observed, precisely because it was a big dermatological monster sitting on top of a big hill made by anthropogenic global warming.

But there is also another,subtler but very important lesson in this event. At any given time we could have what would normally be a “natural” shift to bad conditions. But under global warming, such a shift can be transformed from a disaster to a much bigger disaster. In this way, think of climate change as the steepening of the drop off alongside the road from a 2 foot ditch to a 10 foot embankment. When we drive off the road due to natural forces (some ice, for example) without global warming,we get bounced around a bit. With global warming we get to rely on our airbags to save us, but the airbag deployment will probably break both our arms and mess up our face.

Anyway, the confirmation of the role of El Nino comes from new research discussed here.

The Keeling Curve

Greg Laden — Tue, 26 Aug 2014 21:05:37 +0000

The Keeling Curve is the measurement of CO2 in the Earth’s atmosphere. As we burn fossil fuel or damage “Carbon sinks” we increase that number. The Keeling curve is at the root of much of the science of global warming. It goes up over time because of the release of fossil Carbon, and it wiggles up and down at shorter time scales for other reasons. For example, the curve drops during the Northern Hemisphere summer because the plants on the north side of the globe take in some of the CO2 and make it temporarily into plant tissue. During the northern winter the reverse happens. (There is a lot more land in the Northern Hemisphere).

Anyway, the Keeling Curve is now a movie! And you can watch it for free here:

Source

Bumping against the 400ppm arbitrary but scary number.

Greg Laden — Sun, 13 Apr 2014 17:09:02 +0000

This Scripps Institution of Oceanography, UC San Diego website provides daily updates, analysis, and information on the state of climate. Follow @Keeling_curve to get daily updates of the CO2 value. Through this site, the public can also help support the continuation of the iconic Keeling Curve and of complementary measurements of atmospheric oxygen made at … Continue reading →