Earth's energy budget remained out of balance despite unusually low solar activity

Jan 30, 2012 By Adam Voiland
A prolonged solar minimum left the sun's surface nearly free of sunspots and accompanying bright areas called faculae between 2005 and 2010. Total solar irradiance declined slightly as a result, but the Earth continued to absorb more energy than it emit throughout the minimum. Credit: NASA Goddard's Scientific Visualization Studio

(PhysOrg.com) -- A new NASA study underscores the fact that greenhouse gases generated by human activity -- not changes in solar activity -- are the primary force driving global warming.

The study offers an updated calculation of the Earth's energy imbalance, the difference between the amount of absorbed by Earth's surface and the amount returned to space as heat. The researchers' calculations show that, despite unusually low between 2005 and 2010, the planet continued to absorb more energy than it returned to space.

James Hansen, director of NASA's Goddard Institute for Space Studies (GISS) in New York City, led the research. published the study last December.

Total solar irradiance, the amount of energy produced by the sun that reaches the top of each square meter of the Earth's atmosphere, typically declines by about a tenth of a percent during cyclical lulls in solar activity caused by shifts in the sun's . Usually solar minimums occur about every eleven years and last a year or so, but the most recent minimum persisted more than two years longer than normal, making it the longest minimum recorded during the satellite era.

Pinpointing the magnitude of Earth's energy imbalance is fundamental to because it offers a direct measure of the state of the climate. Energy imbalance calculations also serve as the foundation for projections of future . If the imbalance is positive and more energy enters the system than exits, Earth grows warmer. If the imbalance is negative, the planet grows cooler.

A graph of the sun's total solar irradiance shows that in recent years irradiance dipped to the lowest levels recorded during the satellite era. The resulting reduction in the amount of solar energy available to affect Earth's climate was about .25 watts per square meter, less than half of Earth's total energy imbalance. Credit: NASA/James Hansen

Hansen's team concluded that Earth has absorbed more than half a watt more solar energy per square meter than it let off throughout the six year study period. The calculated value of the imbalance (0.58 watts of per square meter) is more than twice as much as the reduction in the amount of solar energy supplied to the planet between maximum and minimum solar activity (0.25 watts per square meter).

"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 ," Hansen said.

According to calculations conducted by Hansen and his colleagues, the 0.58 watts per square meter imbalance implies that carbon dioxide levels need to be reduced to about 350 parts per million to restore the energy budget to equilibrium. The most recent measurements show that carbon dioxide levels are currently 392 parts per million and scientists expect that concentration to continue to rise in the future.

Climate scientists have been refining calculations of the Earth's energy imbalance for many years, but this newest estimate is an improvement over previous attempts because the scientists had access to better measurements of ocean temperature than researchers have had in the past.

A chart shows the global reach of the network of Argo floats. Credit: Argo Project Office

The improved measurements came from free-floating instruments that directly monitor the temperature, pressure and salinity of the upper ocean to a depth of 2,000 meters (6,560 feet). The network of instruments, known collectively as Argo, has grown dramatically in recent years since researchers first began deploying the floats a decade ago. Today, more than 3,400 Argo floats actively take measurements and provide data to the public, mostly within 24 hours.

Hansen's analysis of the information collected by Argo, along with other ground-based and satellite data, show the upper ocean has absorbed 71 percent of the excess energy and the Southern Ocean, where there are few Argo floats, has absorbed 12 percent. The abyssal zone of the ocean, between about 3,000 and 6,000 meters (9,800 and 20,000 feet) below the surface, absorbed five percent, while ice absorbed eight percent and land four percent.

The updated energy imbalance calculation has important implications for climate modeling. Its value, which is slightly lower than previous estimates, suggests that most climate models overestimate how readily heat mixes deeply into the ocean and significantly underestimates the cooling effect of small airborne particles called aerosols, which along with and are critical factors in energy imbalance calculations.

"Climate models simulate observed changes in global temperatures quite accurately, so if the models mix heat into the deep ocean too aggressively, it follows that they underestimate the magnitude of the aerosol cooling effect," Hansen said.

Aerosols, which can either warm or cool the atmosphere depending on their composition and how they interact with clouds, are thought to have a net cooling effect. But estimates of their overall impact on climate are quite uncertain given how difficult it is to measure the distribution of the particles on a broad scale. The new study suggests that the overall cooling effect from aerosols could be about twice as strong as current climate models suggest, largely because few models account for how the particles affect clouds.

"Unfortunately, aerosols remain poorly measured from space," said Michael Mishchenko, a scientist also based at GISS and the project scientist for Glory, a satellite mission designed to measure aerosols in unprecedented detail that was lost after a launch failure in early 2011. "We must have a much better understanding of the global distribution of detailed aerosol properties in order to perfect calculations of Earth's energy imbalance," said Mishchenko.

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Telekinetic
1.7 / 5 (6) Jan 30, 2012
"Aerosols, which can either warm or cool the atmosphere depending on their composition and how they interact with clouds, are thought to have a net cooling effect."-from article
Even if these aerosols have a cooling effect, who wants this garbage in the atmosphere? Some of it is from natural sources like sea salt, but a lot of it is from the by-products of human activity. I can't believe that it could be interpreted as a positive counter effect to warming.
antialias_physorg
5 / 5 (1) Jan 30, 2012
And where do you get that they call manmade aresols 'good'?
They talk about aerosols without a qualifier. This can be volcanic ash, Sahara dust, water vapor, or some manmade gunk. (And we did have a big volcanic eruption in 2010...but I won't even pretend to be able to spell the name of the iceland volcano resposnible without googling for it)
Telekinetic
1.6 / 5 (8) Jan 30, 2012
Quite a few knuckleheads on this forum think so.
antialias_physorg
5 / 5 (5) Jan 30, 2012
Well then I'd advise you to comment on what it says in the article. Not on what you THINK it says. Scientists are VERY explicit in what they state (and what they don't state) in their papers. Interpretation is something that should be reserved for tabloids.
Telekinetic
1.9 / 5 (8) Jan 30, 2012
"The new study suggests that the overall cooling effect from aerosols could be about twice as strong as current climate models suggest, largely because few models account for how the particles affect clouds." From the article
That sounds pretty upbeat to me from their end, but that's MY interpretation, which is also my prerogative.
Callippo
2 / 5 (8) Jan 30, 2012
The fight against global warming with aerosols is widespread nonsense, as it deepens the most worrisome impact of global warming, i.e. the droughts. It leads into nucleation of many, but tiny water droplets, which are both source of smog, both cannot condense into rain gravitationally and as such they evaporate before they can contribute to the circulation of watter in the atmosphere. In addition, above certain limit concentration of the nuclei the resulting water droplets are so small, they're absorbing infrared radiation instead of reflecting it.
LVT
4 / 5 (4) Jan 30, 2012
The volcano is called Eyja.. the rest means volcano on a glacier.
wictor
3.3 / 5 (6) Jan 30, 2012
I see that the article is suggesting that changes in solar activity is not the primary factor driving global warming. But neither is it proving that greenhouse gases generated by human activity are the primary factor. Thus I don't understand the subtitle of the article.

Did they also consider the drop in Earth's magnetosphere ? Because the magnetic field got weaker by 10% in the last 150 years. Weaker magnetic field means more ionizing particles from the Sun hitting the atmosphere. That may have a strong influence on the climate. The connection between inonizing particles and cloud formation has been shown at CERN.
Callippo
1 / 5 (4) Jan 30, 2012
Weaker magnetic field means more ionizing particles from the Sun hitting the atmosphere. That may have a strong influence on the climate.
They indeed may have it, but the problem is, this influence can be interpreted in two opposite ways and nobody actually knows, which is the prevailing one in this moment. The increased nucleation of atmosphere may result into more clouds, which are increasing albedo and cooling Earth. But it increases the content of water vapor in the atmosphere too, and the water vapor is the significant green house gas. In addition, the increased ionization of atmosphere actually increases the height of ionosphere, because the mutually repelling charges are expanding it - so that the nucleation of troposphere decreases. During last prolonged minimum of solar activity it has been observed, the global warming of atmosphere stopped temporarily whereas the heating of ocean continued - but no climatic model was able to predict it reliably.
Callippo
1 / 5 (7) Jan 30, 2012
My model connects the global warming period and the period of low solar activity in rather straightforward way, because the dense cloud of neutrinos is attracted with Sun and it shifts the center of mass of solar system beneath the surface of Sun. This prohibits the convection of solar plasma by Coriolis forces and it leads into its overheating. The Sun behaved literally like the pot of water inside of microwave owen and its boiling (which manifests with sun spot bubbles) has been interrupted. This event occurred during 2000 - 2010 period, when the solar system appeared at the center of neutrino cloud. Now this cloud is slowly passing by and the solar activity releases accumulated energy. If my assumptions are correct, then the global warming should decay during next twenty years, but the elevated concentration of atmospheric carbon released both with people, both with permafrost and Arctic sea clathrates can still have irreversible effects to biosphere.
MorituriMax
2.5 / 5 (8) Jan 30, 2012
Why is warm climate bad?

Instead of changing the climate, why don't we adapt our technology to deal with higher water levels and temperatures. Build fields higher up, build buildings to adapt to rising water, build better dykes and barriers to channel water away from areas that can't deal with it.
StarGazer2011
2.2 / 5 (13) Jan 30, 2012
The most hilarious thing about this 'research' is that despite Hansens cludged together 0.58W/m2 imbalance, there hasnt been any warming during the period under consideration. So before he has even published, his core claim is falsified by measurments of no warming. You would have to be pretty slow to still be buying this.
StarGazer2011
2.3 / 5 (12) Jan 30, 2012
Further, and I havent read the paper, im not clear on how Hansen claims to measure this imbalance. TSI at the top of atmosphere can be measured with satellites sure, and radiant temperature at the surface can be measured with Argo and other instruments, but just because the bottom is radiating less than went into the top doesnt mean it is warming up (and instruments including Argo show its not). It possibly just means that the energy is being reflected (by clouds) before it reaches the bottom to be measured. I would bet that the illusory 'imbalance' is actually the net blocking effect of clouds rather than any evidence of CAGW.
Howhot
2.6 / 5 (5) Jan 30, 2012
Wow, the AGW skeptics just have to fall all over themselves to just to make an irrelevant useless made up fib to try to discredit facts and observations that are indisputable.

What has been documented is an imbalance in the 'push', the amount of energy coming in vs that energy going out. A complex problem to measure, but that is what satellites, ballon observations are for.

but it's worth noting because this provides unequivocal evidence that THE SUN IS NOT the dominant driver of global warming," Hansen said.


Unequivocal is a pretty strong statement coming from a scientist of his stature. In fact, all the science in the world says it excess heat is from AGW. Man made air pollution from fossil fuels.

So Stargazer, want to eat crow now or later?
antialias_physorg
3.7 / 5 (6) Jan 30, 2012
Instead of changing the climate, why don't we adapt our technology to deal with higher water levels and temperatures.

Warmer temepratures also mean more energy in the air: More storms (with attendant damages and soil erosion), floods, etc.
You can't keep that all in check with technology.

Then there's the chance that an entire part of the animal kingdom might not be able to cope with that sort of change which would lead to the food chain being broken (i.e. we'd starve)

Build fields higher up
Do you have any idea how many cities lie next to the ocean or a river? All of them. Do you suggest moving them all? Where to? Good luck with that.
Howhot
2.3 / 5 (6) Jan 31, 2012
Then there's the chance that an entire part of the animal kingdom might not be able to cope with that sort of change which would lead to the food chain being broken (i.e. we'd starve)


Lets not forget the Animal Kingdom. People tend to forget we have millions of acres set aside for grazing (and growing) dinner. If the cows are too hot to reproduce or there is not enough water to sustain a 600 pound steer. Oh but the AGW deniers will say everything is fine until their car overheats.


Sean_W
2 / 5 (8) Jan 31, 2012
It's all indisputable. It's unequivocal. People who disagree are buffoons so don't bother listening to them.

Hansen--he's the guy who says the oceans will boil in a century and predicted that important roads would be under water by 2000 right? Maybe he should try getting something right before we accept his "stature" as qualification to label things as unequivocal.
kaasinees
1.3 / 5 (3) Jan 31, 2012
And where do you get that they call manmade aresols 'good'?
They talk about aerosols without a qualifier.


chemtrails all over europe and america. there are even gov reports about this in germany and USA.

We are currently entering solar max and pole shift is going on for a decade or so (this process takes a thousand years average).
So they might have been spraying aerosols as a precaution.

This can be volcanic ash, Sahara dust, water vapor, or some manmade gunk. (And we did have a big volcanic eruption in 2010...but I won't even pretend to be able to spell the name of the iceland volcano resposnible without googling for it)

Not sure about the exact amount but i think 2-4 eruptions in 2011 and 2010 i do know one was in mexico with some funky name.
axemaster
2.3 / 5 (3) Jan 31, 2012
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," Hansen said.

And yet deniers will continue to say "it's the Sun!" as before... that's a prediction backed by solid evidence!
Shootist
2.6 / 5 (5) Jan 31, 2012
"Aerosols, which can either warm or cool the atmosphere depending on their composition and how they interact with clouds, are thought to have a net cooling effect."-from article
Even if these aerosols have a cooling effect, who wants this garbage in the atmosphere? Some of it is from natural sources like sea salt, but a lot of it is from the by-products of human activity. I can't believe that it could be interpreted as a positive counter effect to warming.


One medium size volcano releases more toxins, and other yada yada, in a year, than all the automobiles on the planet. All of the geologic processes on the planet release several orders of magnitude more toxins than all of mankind's activities taken together.

Scale, or to put it even more simply, the poison is in the dose.
AWaB
2.3 / 5 (3) Jan 31, 2012
I went to the actual paper b/c I thought it would be enlightening. I thought this would be a good proof against skeptics. Unfortunately, this guy used so many references from previous studies that it would take far longer than I have to validate his numerous assumptions. It's a shame b/c he wrote in such a high-handed manner that you would have thought he had something valid to say.
kaasinees
1.8 / 5 (5) Jan 31, 2012
All of the geologic processes on the planet release several orders of magnitude more toxins than all of mankind's activities taken together.


That is not true, as it is not even poison.
ryggesogn2
2.3 / 5 (7) Jan 31, 2012
All of the geologic processes on the planet release several orders of magnitude more toxins than all of mankind's activities taken together.


That is not true, as it is not even poison.

"Poisonous gas from African lake poses threat to millions

Trapped methane and carbon dioxide could be set loose by a quake or landslide, say scientists
"
http://www.guardi...-co2-gas
Howhot
3 / 5 (2) Jan 31, 2012
From the article;
The study offers an updated calculation of the Earth's energy imbalance, the difference between the amount of solar energy absorbed by Earth's surface and the amount returned to space as heat


Its a big problem for the Global Warming Deniers, How hot will temperatures rise? How quickly ... etc. All of the load mouths from BigOil/Conservative goons can't answer the science and observations we see.
Howhot
3 / 5 (2) Jan 31, 2012
I think this needs repeating: "Lets not forget the Animal Kingdom. People tend to forget we have millions of acres set aside for grazing (and growing) dinner. If the cows are too hot to reproduce or there is not enough water to sustain a 600 pound steer. Oh but the AGW deniers will say everything is fine until their car overheats."

What loosers the anti-environmental people are.
kaasinees
1 / 5 (2) Jan 31, 2012
"Poisonous gas from African lake poses threat to millions

Trapped methane and carbon dioxide could be set loose by a quake or landslide, say scientists
"
http://www.guardi...-co2-gas


Methane is a natural gas, CO2 is natural. So tell me something i did not know already?

In fact, without these processes our atmosphere would slowly deplete, nuitrients would slowly deplete thus these processes are required for life thus they are not poison.

Now if we are talking about african lakes and other lakes thatharbor compressed gasses in the deep, yes they can become poison (crawling sulfur gas) which is poisonous to most mammals. But still it is not poison.

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