Welcome to DU! The truly grassroots left-of-center political community where regular people, not algorithms, drive the discussions and set the standards. Join the community: Create a free account Support DU (and get rid of ads!): Become a Star Member All Forums Issue Forums Culture Forums Alliance Forums Region Forums Support Forums Help & Search


(41,705 posts)
Tue Jan 31, 2012, 04:20 PM Jan 2012

Global warming not caused by increased solar activity (NASA)


A new NASA study has confirmed that it's greenhouse gases - not changes in solar activity - that are the main cause of global warming


And Hansen's team has concluded that the Earth absorbed over half a watt more solar energy per square meter than it emitted throughout the six-year study period. This imbalance is more than twice as much as the fall in incoming solar energy between maximum and minimum solar activity.

"The fact that we still see a positive imbalance despite the prolonged solar minimum isn't a surprise, given what we've learned about the climate system, but it's worth noting because this provides unequivocal evidence that the sun is not the dominant driver of global warming," says James Hansen, director of NASA's Goddard Institute for Space Studies.

According to the team's calculations, the imbalance implies that carbon dioxide levels need to be reduced to about 350 parts per million to restore the energy budget to equilibrium. They're currently 392 parts per million, and scientists expect the figure to continue to rise in the future.


17 replies = new reply since forum marked as read
Highlight: NoneDon't highlight anything 5 newestHighlight 5 most recent replies


(178 posts)
5. Oh those wacky scientists and their facts
Tue Jan 31, 2012, 05:36 PM
Jan 2012

If baby Jesus wanted me to make less carbon dioxide,
he wouldn't have made burned cow meat so delicious.



(5,917 posts)
8. what's with the misspelling of the word "the"
Tue Jan 31, 2012, 05:49 PM
Jan 2012

teh .the virtue or power inherent in a person or thing existing in harmony with the Tao


(9,001 posts)
16. while I like your take, it's an intertubes thing.
Tue Jan 31, 2012, 11:00 PM
Jan 2012

typing too fast in chat rooms= teh
or using 111 instead of !!!
or LULZ instead of LOLS

"all your base are belong to us"

Makes your head want to asplode.


(133 posts)
13. Hansen_etal_2011
Tue Jan 31, 2012, 08:54 PM
Jan 2012

You can read Dr. Hansen's paper here (courtesy of the Goddard Institute of Space Sciences)


For those of you who wish the 'short version' that will drive your Republican friends into a frenzy - it goes like this. (I'll go easy on the math)

Hansen's team used improved observations of heat uptake by the oceans from inbound surface radiation from our sun and compared those measurements with our instrumental record of stratospheric aerosols together against the record of solar activity.

The idea is simple - our planet is a water planet and as such the oceans represent a considerable heat sink. For a long time we did not have reliable metrics on ocean heating but once we did the scope of our planets warming began to fall into place. Aerosols, which occur naturally as the product of volcanism and by the human activity of combustion and agricultural burning, tends to shield the planet from heating but also holding some heat along the way.

Now enter the Sun. We have very good instrumental records on solar activity so we can make very good estimates of the amount of solar radiation reaching the surface.

So put simply, take the solar energy from the sun (in watts per square meter) and calculate in the amount absorbed by the oceans and the amount reflected back into space by aerosols. Keep in mind that our planet largely radiates back nearly all the energy we receive.

What the paper shows is that solar activity cannot be responsible for our observed heating and that other forcing factors, changes in non condensing green house gases (GHG) and aerosols contribute to our planets heat retention.

Two observations I found interesting in the paper were the mention that earlier models used a more aggressive ocean mixing model which would have changed the amount of heat uptake calculated, and that currently the non polar region glaciers (alpine) are estimated as a greater contributor of sea level rise.

Hansen is always quite thorough in his submissions, clocking in at 29 pages, this paper was no exception. He makes some interesting comparisons of the GISS modelE-R, the GFDL model and the NCAR CCSM3 model in terms of their climate sensitivity and response.

This paper is describing an energy balance model (EBM). The first EBM was created by Svante Arrhenius in 1896. It is his prediction that if you double the CO2 in the atmosphere that the average global temperatures will increase between 2 and 4 degrees Celsius. This paper and all other papers like it seek to fine tune that estimated heating.

While it may baffle your Republican in-laws, its important to bear in mind that the implication of non-condensing green house gases is by inference. The "skeptics" have long pointed to solar variation as the source of our planetary warming, what Hansen has demonstrated by both data and model is that this is not the case.


(12,121 posts)
15. Only in America. Only here do we need assurance that the 1% are wrong.
Tue Jan 31, 2012, 09:51 PM
Jan 2012

Only here do we need our space agency to assure us that the 99% are right. The 99% of scientists who know global warming due to greenhouse gases is happening and disturbing our climatic systems all over the world.

Only here can people see the glaciers melting, the ice caps melting, ice sheets cracking, sea levels rising, etc. etc. etc. and be so successfully propagandized that they could even doubt the visible evidence all around them. Documented changes over decades. And we've gotta be told that Fox GOP News and other right wingers are grasping at straws and it is not the solar flares that have warmed our planet so extremely much in such a short period.


(5,019 posts)
17. I mean, really, we can measure the luminosity of stars millions of light years away.
Tue Jan 31, 2012, 11:31 PM
Jan 2012

Why is it so hard for them to believe that we can do the same for the Sun?

Latest Discussions»Latest Breaking News»Global warming not caused...