Thanks for your question on geo-engineering. The main factor besides co2-equivalent warming is the Aerosol Masking Effect from sulfur pollution. Before industrialization the burning of wood with sulfur pollution cooled Earth as much as any CO2-equivalent warming. https://www.israel21c.org/we-need-to-rethink-everything-we-know-about-global-warming/
"Using this new methodology, Rosenfeld and his colleagues were able to more accurately calculate aerosols’ cooling effects on the Earth. They discovered this effect is nearly two times higher than previously thought."Daniel Rosenfeld's research group determined that in fact the Aerosol Masking Effect is twice as bad as previously thought - this means that global warming is actually much worse now than we realize - and a 40% decrease in burning coal will heat up EArth another 1 degree Celsius (due to lack of the sulfur pollution). Already the scrubbing of diesel smoke on cargo ships has lead to a spike in global temperature increase as James E. Hansen has determined - thereby making the reduction of sulfur pollution the current single fastest increase in global temperatures.
I got arrested climbing the US Navy fence for Project ELF - a one-way extremely low frequency communication system to the Trident nuclear subs - and Project ELF did get shutdown. There is one in Australia also - set up by the US military - I'm not sure if that is still going or was part of Project ELF. I did my "career" in environmental activism - so I am aware that the U.S. military tested biological weapons on citizens - and I have researched the extreme problem of toxic waste, etc. For example the Two headed depleted uranium babies now being born - I was arrested also at Alliant Techsystems that previously was headquartered in Twin Cities Minnesota, where I grew up. So they are the largest manufacturer of depleted uranium weapons (now being used in Ukraine).
As bad as the pollution is - whether done by secret military projects - it does not compare to the current 1000 to 5000 gigatons of CO2 being emitted in the past 200 years since the natural background rate of CO2 emissions is only 12 gigatons. So in terms of life on Earth - we currently are experiencing by far the fastest emission of CO2 - and previous spikes in CO2 on Earth did cause mass extinction of species aka "biological annihilation."
So if you study http://arctic-news.blogspot.com they point out that the Clouds Tipping Point occurs at 1200 ppm of CO2 but that includes CO2 equivalent (mainly methane). There's 1200 gigatons of pressurized methane in the world's largest ocean shelf - the East Siberian Arctic Shelf - and this got dismissed by the IPCC as potentially only a problem in 100 years. Natalia Shakhova's research group has proven that already the ESAS is emitting methane at a rate more than the rest of the world's oceans - and as much as the rest of the arctic methane.
https://acp.copernicus.org/articles/24/6359/2024/
"Surface networks in the Arctic may miss a future methane bomb"Since it is pressurized that means it can easily "burst" out and just a 50 gigaton burst will double atmospheric temperatures. This would cause a collapse of the "bread baskets" on Earth since our farming is mainly in the interior of the continents that are five degrees Fahrenheit warmer than the global average. So just as now famine is accelerating from extreme weather - if civilization collapses from drought - then the 400 plus nuclear power plants won't get maintained. Such a meltdown rate would cause the ozone layer to get destroyed - just as 1200 PPM of co2 also heats up Earth dramatically as the Clouds Tipping Point.
"Several studies have highlighted the importance of CH4 emissions from the Arctic Ocean, particularly in shallow waters underlain by permafrost (Damm et al., 2010; Kort et al., 2012). Subsea permafrost thaw has been observed in the ESAS (East Siberian Arctic Shelf) and the importance of this region has been highlighted, for instance by Shakhova et al. (2015, 2019) and Wild et al. (2018). Future estimates suggest that around 50 Gt of methane could be released from gas hydrates in the ESAS alone over the next 50 years (Shakhova et al., 2010), consistent with present annual estimates (e.g. Berchet et al., 2016)."
So https://arctic-news.blogspot.com/p/clouds-feedback.html
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/1999GL011197
This is due to increased water vapor.
https://e360.yale.edu/features/why-clouds-are-the-key-to-new-troubling-projections-on-warming
"The tipping point would not be reached until CO2 levels were at around 1200 ppm, more than four times pre-industrial levels, and three times current levels. But once it was passed, he projected that temperatures would soar by an additional 8 degrees C (14.4 degrees F) as a result of the lost clouds. "
https://www.nature.com/articles/s41561-019-0310-1
The stratocumulus clouds that top turbulent boundary layershttps://arxiv.org/abs/2305.15477
over large swaths of subtropical oceans are unusual among
Earth’s clouds: the turbulence that sustains them is driven by
longwave radiative cooling of the cloud tops, rather than by heat-
ing at the surface 1
. The reason is that cloud droplets absorb and
emit longwave radiation so efficiently that the clouds are essentially
opaque to longwave radiation. By contrast, the free troposphere
above them is dry and has few clouds, making it relatively trans-
parent to longwave radiation. Therefore, the longwave flux down-
welling just above the cloud tops originates in higher and cooler
atmospheric layers and is 50–90 W m−2 weaker than the upwelling
longwave flux emitted by the cloud tops (Fig. 1) 1
. The resulting
longwave cooling of the cloud tops drives convection, which pen-
etrates the boundary layer and supplies the clouds with moisture
from the surface. The convective moistening and radiative cool-
ing of the cloud layer are balanced by turbulent entrainment of
dry and warm free-tropospheric air across the trade inversion—
the usually sharp interface between the boundary layer and the
above-lying free troposphere (Fig. 1). Stratocumulus decks break
up when the longwave cooling of the cloud tops becomes too weak
to propel air parcels to the surface or when the turbulent entrain-
ment of dry and warm free-tropospheric air across the inversion
becomes too strong2
.
Key processes in stratocumulus-topped boundary layers, such as
entrainment across the inversion, occur at scales of tens of metres
and smaller3–6
. This is much too small to be resolvable in global cli-
mate models (GCMs), which currently have horizontal resolutions
of tens of kilometres7
. GCMs therefore resort to parameterizations,
which relate stratocumulus occurrence to resolved large-scale vari-
ables, such as temperature or humidity. However, the parameteriza-
tions are notoriously inaccurate: GCMs severely underestimate the
prevalence of stratocumulus decks8,9
, and confidence in the simu-
lations of their climate change response is low10
. As stratocumulus
clouds cover 20% of the tropical oceans 11 and critically affect the
Earth’s energy balance (they reflect 30–60% of the shortwave radia-
tion incident on them back to space 1
), problems simulating their
https://iopscience.iop.org/article/10.1088/1748-9326/ac18e9
It is found that Arctic ozone loss is associated with an increase in high clouds by modifying static stability in the upper troposphere. Stratospheric ozone loss allows more UV radiation to reach the surface. On the contrary, the increase in high clouds results in a reduction of surface UV radiation. Interestingly, a composite analysis suggests that this cloud masking effect is found to be stronger than that from stratospheric ozone loss over the Siberian Arctic in spring. These results suggest that we should pay more attention to the high-ozone events which would lead to more surface UV radiation by the cloud effects.
We find that the surface temperature change is caused mostly by the stratosphere being much colder when ozone is absent; this makes it drier, substantially weakening the greenhouse effect. We also examine the effect of the structure of the upper troposphere and lower stratosphere on the formation of clouds, and on the global circulation. At low ozone, both high and low clouds become more abundant, due to changes in the tropospheric stability.
No comments:
Post a Comment