Nearly 30 dangerous feedback loops could permanently shift the Earth's climate, scientists say

[NickB79]

Last edited Tue Feb 21, 2023, 08:19 PM - Edit history (1)

A group of international scientists from institutions including Oregon State University, Exeter University and the Potsdam Institute for Climate Impact Research in Germany, pored over climate literature to identify 41 climate feedback loops. Of these, they found that 27 are driving up global temperatures, according to the study published Friday in the scientific journal One Earth, while just seven are helping to slow the pace of climate crisis.

William Ripple, Professor of Ecology at Oregon State University and a lead author on the study, told CNN that forest die-off, smoldering peatlands and thawing permafrost were particularly worrisome.

“These feedbacks may be large and are difficult to accurately quantify,” Ripple told CNN.

The researchers were surprised by the large number of amplifying climate feedback loops they found, he added.

“To the best of our knowledge, this is the most extensive list available of climate feedback loops, and not all of them are fully considered in climate models,” Christopher Wolf, a postdoctoral scholar at Oregon State University and the study’s other lead author, said in a statement.

https://amp.cnn.com/cnn/2023/02/17/world/climate-feedback-loops-tipping-points-arctic-ice-intl/index.html

Every time I see someone say that the best models "only" show 3C of warming by 2100, instead of the worst-case 4-6C level of warming, I think of stuff like this.

[ColinC]

1. link?

[NickB79]

4. Sorry, just added it

[ColinC]

7. Thanks!!

[keithbvadu2]

2. "Only"... Just slightly less bad but nowhere near anything 'good'.

[Finishline42]

3. Makes me concerned if we have already passed the tipping point...

During the world-wide economic shutdown in the early months of pandemic shutdown I assumed that CO2 readings at Mauna Loa would have dropped. That you could look at the data and see where the World decreased economic activity by significant amounts (kind of like how the sky got so clear after the grounding of commercial air traffic after 9/11). But it's not there.

Warming the Arctic has thawed the tundra that has released frozen methane deposits. Thaw more tundra, release more methane.

Just like reduced Arctic Ice allows the sun to warm the Arctic waters which reduces the amount of Arctic ice...

[hatrack]

6. There's also nitrous oxide, a GHG which isn't directly tied to fossil fuel combustion.

Partially from wet-paddy agriculture, partially from the use (particularly the overuse) of synthetic nitrogen fertilizer. COVID probably wouldn't have had that big of an impact on output.

[NNadir]

8. Nitrous oxide is the end product of the metabolism of NO2 generated by combustion.

NO2 reacts with water and oxygen to form nitric acid, which rains out, is neutralized by things like carbonates, and then enters the nitrogen cycle, whereupon some organisms generate N2O.

NO2 is readily formed by combustion, although catalytic converters address it to a limited extent.

If however, one stands on the beach in Southern California or many other cities, that brown layer over the ocean is NO2, from combustion.

The sink for N2O is radiation. As my son is working to become a nuclear engineer, I discuss that fact with him all the time.

I note that the use, as opposed to the easy to target, overuse of fixed nitrogen fertilizers also results in N2O, a greenhouse gas to be sure, and also an ozone depletion agent.

More problematic from agriculture is methane. Just this weekend as I went through the journal Environmental Science and Technology, I came across this interesting paper: Fossil-Fuel and Food Systems Equally Dominate Anthropogenic Methane Emissions in China, Shuhan Liu, Kaiyun Liu, Kun Wang, Xingcai Chen, and Kai Wu, Environmental Science & Technology 2023 57 (6), 2495-2505.

If we announce that starvation is "green," we may have some kind of point, but I suspect it isn't going to be overwhelmingly popular.

Of course, a lot of things that are popular haven't done shit to address climate change either, although some things that are unpopular and laced with stupid associations in popular might just make things better.

The deeper we go, the more glib and clueless we become.