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OK, so first, look at the NASA link:
http://science.nasa.gov/science-news/science-at-nasa/2012/22mar_saber/
[font face=Serif][font size=5]Solar Storm Dumps Gigawatts into Earth's Upper Atmosphere[/font]
[font size=3]March 22, 2012: A recent flurry of eruptions on the sun did more than spark pretty auroras around the poles. NASA-funded researchers say the solar storms of March 8th through 10th dumped enough energy in Earth’s upper atmosphere to power every residence in New York City for two years.
“This was the biggest dose of heat we’ve received from a solar storm since 2005,” says Martin Mlynczak of NASA Langley Research Center. “It was a big event, and shows how solar activity can directly affect our planet.”
Mlynczak is the associate principal investigator for the SABER instrument onboard NASA’s TIMED satellite. SABER monitors infrared emissions from Earth’s upper atmosphere, in particular from carbon dioxide (CO[font size=1]2[/font]) and nitric oxide (NO), two substances that play a key role in the energy balance of air hundreds of km above our planet’s surface.
“Carbon dioxide and nitric oxide are natural thermostats,” explains James Russell of Hampton University, SABER’s principal investigator. “When the upper atmosphere (or ‘thermosphere’) heats up, these molecules try as hard as they can to shed that heat back into space.”
…[/font][/font]
[font size=3]March 22, 2012: A recent flurry of eruptions on the sun did more than spark pretty auroras around the poles. NASA-funded researchers say the solar storms of March 8th through 10th dumped enough energy in Earth’s upper atmosphere to power every residence in New York City for two years.
“This was the biggest dose of heat we’ve received from a solar storm since 2005,” says Martin Mlynczak of NASA Langley Research Center. “It was a big event, and shows how solar activity can directly affect our planet.”
Mlynczak is the associate principal investigator for the SABER instrument onboard NASA’s TIMED satellite. SABER monitors infrared emissions from Earth’s upper atmosphere, in particular from carbon dioxide (CO[font size=1]2[/font]) and nitric oxide (NO), two substances that play a key role in the energy balance of air hundreds of km above our planet’s surface.
“Carbon dioxide and nitric oxide are natural thermostats,” explains James Russell of Hampton University, SABER’s principal investigator. “When the upper atmosphere (or ‘thermosphere’) heats up, these molecules try as hard as they can to shed that heat back into space.”
…[/font][/font]
A little more reading is in order:
http://www.giss.nasa.gov/research/briefs/lacis_01/
[font face=Serif][font size=5]CO[font size=1]2[/font]: The Thermostat that Controls Earth's Temperature[/font]
By Andrew Lacis — October 2010
[font size=3]A study by GISS climate scientists recently published in the journal Science shows that atmospheric CO[font size=1]2[/font] operates as a thermostat to control the temperature of Earth.
There is a close analogy to be drawn between the way an ordinary thermostat maintains the temperature of a house, and the way that atmospheric carbon dioxide (and the other minor non-condensing greenhouse gases) control the global temperature of Earth. The ordinary thermostat produces no heat of its own. Its role is to switch the furnace on and off, depending on whether the house temperature is lower or higher than the thermostat setting. If we were to carefully monitor the temperature of the house, we would see that the temperature does not stay constant at the set value, but rather exhibits a "natural variability" as the house temperature slips below the set value and then overshoots the mark with a time constant of minutes to tens of minutes, because of the thermal inertia of the house and because heating by the furnace (when it is on) is more powerful than the steady heat loss to the outdoors. If the thermostat is suddenly turned to a very high setting, the temperature will begin to rise at a rate dictated by the inertia of the house and strength of the furnace. Turning the thermostat back to normal will stop the heating.
Atmospheric carbon dioxide performs a role similar to that of the house thermostat in setting the equilibrium temperature of the Earth. It differs from the house thermostat in that carbon dioxide itself is a potent greenhouse gas (GHG) warming the ground surface by means of the greenhouse effect. It is this sustained warming that enables water vapor and clouds to maintain their atmospheric distributions as the so-called feedback effects that amplify the initial warming provided by the non-condensing GHGs, and in the process, account for the bulk of the total terrestrial greenhouse effect. Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. Together with the similar non-linear responses involving the ocean heat capacity, the net effect is the "natural variability" that the climate system exhibits regionally, and on inter-annual and decadal timescales, whether the global equilibrium temperature of the Earth is being kept fixed, or is being forced to re-adjust in response to changes in the level of atmospheric GHGs.
This assessment comes about as the result of climate modeling experiments which show that it is the non-condensing greenhouse gases such as carbon dioxide, methane, ozone, nitrous oxide, and chlorofluorocarbons that provide the necessary atmospheric temperature structure that ultimately determines the sustainable range for atmospheric water vapor and cloud amounts, and thus controls their radiative contribution to the terrestrial greenhouse effect. From this it follows that these non-condensing greenhouse gases provide the temperature environment that is necessary for water vapor and cloud feedback effects to operate, without which the water vapor dominated greenhouse effect would inevitably collapse and plunge the global climate into an icebound Earth state.
Within only the past century, the CO[font size=1]2[/font] control knob has been turned sharply upward toward a much hotter global climate. The pre-industrial level of atmospheric carbon dioxide was about 280 ppm, which is representative of the interglacial maximum level of atmospheric CO[font size=1]2[/font]. During ice age extremes, the level of atmospheric CO[font size=1]2[/font] drops to near 180 ppm, for which the global temperature is about 5 °C colder. The rapid recent increase in atmospheric CO[font size=1]2[/font] has been attributed to human industrial activity, primarily the burning of fossil fuels. This has pushed atmospheric CO[font size=1]2[/font] toward the 400 ppm level, far beyond the interglacial maximum. The climate system is trying to respond to the new setting of the global temperature thermostat, and this response has been the rise in global surface temperature by about 0.2 °C per decade for the past three decades.
It has been suggested that we are well past the 300 to 350 ppm target level for atmospheric CO[font size=1]2[/font] beyond which dangerous anthropogenic interference in the climate system would be expected to exceed the 25% risk tolerance for impending degradation of land and ocean ecosystems, sea level rise, and inevitable disruption of the socio-economic and food-producing infrastructure (Hansen et al. 2008). This prospect of a rising risk of triggering unacceptable environmental consequences makes reduction and control of atmospheric CO[font size=1]2[/font] a serious and pressing issue for humanity, worthy of real time attention.
…[/font][/font]
By Andrew Lacis — October 2010
[font size=3]A study by GISS climate scientists recently published in the journal Science shows that atmospheric CO[font size=1]2[/font] operates as a thermostat to control the temperature of Earth.
There is a close analogy to be drawn between the way an ordinary thermostat maintains the temperature of a house, and the way that atmospheric carbon dioxide (and the other minor non-condensing greenhouse gases) control the global temperature of Earth. The ordinary thermostat produces no heat of its own. Its role is to switch the furnace on and off, depending on whether the house temperature is lower or higher than the thermostat setting. If we were to carefully monitor the temperature of the house, we would see that the temperature does not stay constant at the set value, but rather exhibits a "natural variability" as the house temperature slips below the set value and then overshoots the mark with a time constant of minutes to tens of minutes, because of the thermal inertia of the house and because heating by the furnace (when it is on) is more powerful than the steady heat loss to the outdoors. If the thermostat is suddenly turned to a very high setting, the temperature will begin to rise at a rate dictated by the inertia of the house and strength of the furnace. Turning the thermostat back to normal will stop the heating.
Atmospheric carbon dioxide performs a role similar to that of the house thermostat in setting the equilibrium temperature of the Earth. It differs from the house thermostat in that carbon dioxide itself is a potent greenhouse gas (GHG) warming the ground surface by means of the greenhouse effect. It is this sustained warming that enables water vapor and clouds to maintain their atmospheric distributions as the so-called feedback effects that amplify the initial warming provided by the non-condensing GHGs, and in the process, account for the bulk of the total terrestrial greenhouse effect. Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. Together with the similar non-linear responses involving the ocean heat capacity, the net effect is the "natural variability" that the climate system exhibits regionally, and on inter-annual and decadal timescales, whether the global equilibrium temperature of the Earth is being kept fixed, or is being forced to re-adjust in response to changes in the level of atmospheric GHGs.
This assessment comes about as the result of climate modeling experiments which show that it is the non-condensing greenhouse gases such as carbon dioxide, methane, ozone, nitrous oxide, and chlorofluorocarbons that provide the necessary atmospheric temperature structure that ultimately determines the sustainable range for atmospheric water vapor and cloud amounts, and thus controls their radiative contribution to the terrestrial greenhouse effect. From this it follows that these non-condensing greenhouse gases provide the temperature environment that is necessary for water vapor and cloud feedback effects to operate, without which the water vapor dominated greenhouse effect would inevitably collapse and plunge the global climate into an icebound Earth state.
Within only the past century, the CO[font size=1]2[/font] control knob has been turned sharply upward toward a much hotter global climate. The pre-industrial level of atmospheric carbon dioxide was about 280 ppm, which is representative of the interglacial maximum level of atmospheric CO[font size=1]2[/font]. During ice age extremes, the level of atmospheric CO[font size=1]2[/font] drops to near 180 ppm, for which the global temperature is about 5 °C colder. The rapid recent increase in atmospheric CO[font size=1]2[/font] has been attributed to human industrial activity, primarily the burning of fossil fuels. This has pushed atmospheric CO[font size=1]2[/font] toward the 400 ppm level, far beyond the interglacial maximum. The climate system is trying to respond to the new setting of the global temperature thermostat, and this response has been the rise in global surface temperature by about 0.2 °C per decade for the past three decades.
It has been suggested that we are well past the 300 to 350 ppm target level for atmospheric CO[font size=1]2[/font] beyond which dangerous anthropogenic interference in the climate system would be expected to exceed the 25% risk tolerance for impending degradation of land and ocean ecosystems, sea level rise, and inevitable disruption of the socio-economic and food-producing infrastructure (Hansen et al. 2008). This prospect of a rising risk of triggering unacceptable environmental consequences makes reduction and control of atmospheric CO[font size=1]2[/font] a serious and pressing issue for humanity, worthy of real time attention.
…[/font][/font]
http://www.giss.nasa.gov/research/briefs/schmidt_05/
[font face=Serif][font size=5]Taking the Measure of the Greenhouse Effect[/font]
By Gavin Schmidt — October 2010
[font size=3] Most of us have heard that the greenhouse effect keeps the planet much warmer than it would be otherwise, and similarly we may have heard that increasing amounts of greenhouse gases are enhancing the natural greenhouse effect. But few of us appreciate what exactly it is in the atmosphere that makes the effect work and why small changes in trace gases such as carbon dioxide (CO[font size=1]2[/font]) might make a difference.
It has been understood since the 19th century that some gases absorb infrared radiation (IR) that is emitted by the planet, slowing the rate at which the planet can cool and warming the surface. These so-called greenhouse gases include carbon dioxide and water vapor, as well as ozone and methane among others. Note, however, that the bulk of the atmosphere is made up of nitrogen and oxygen molecules which don't absorb IR at all. Less well appreciated is that clouds (made of ice particles and/or liquid water droplets) also absorb infrared radiation and contribute to the greenhouse effect, too. Clouds, of course, also interfere with incoming sunlight, reflecting it back out to space, making their net effect one of cooling, but their contribution to the greenhouse effect is important.
The size of the greenhouse effect is often estimated as being the difference between the actual global surface temperature and the temperature the planet would be without any atmospheric absorption, but with exactly the same planetary albedo, around 33°C. This is more of a "thought experiment" than an observable state, but it is a useful baseline. Another way of quantifying the effect is to look at the difference between the infrared radiation emitted at the surface of the Earth, and the amount that is emitted to space at the top of the atmosphere. In the absence of the greenhouse effect, this would be zero (in other words, no difference). In actuality the surface emits about 150 Watts per square meter (W/m[font size=1]2[/font]) more than goes out to space.
So of all the greenhouse substances in the atmosphere, which of them absorbs what? This is a more complicated issue than it might first appear because of the nature of the absorption and the complex distribution of absorbers both horizontally and vertically. Different substances absorb different frequencies of IR, and the different parts of the planet differ wildly in how much IR is being emitted (based as it is on surface temperature) and how much cloud and water vapor there is at that location (carbon dioxide is very well mixed). Indeed, some wavelengths of IR can be absorbed by both water vapor or clouds, or water vapor and CO[font size=1]2[/font]. This "spectral overlap" means that if you remove a substance, the change in how much IR is absorbed will be less than if you only had that substance in the air. Alternately, the impact of all the substances together is less than what you would get if you added up their individual components. This needs to be taken into account in any attribution of the greenhouse effect.
We use the GISS model of radiative transfer through the global atmosphere to try and break down the attribution using realistic distributions of local temperature, water vapor and clouds. By removing each of the absorbers in turn and calculating the absorption for many different combinations, we can calculate all the overlaps and allocate the absorption fairly. We find that water vapor is the dominant substance — responsible for about 50% of the absorption, with clouds responsible for about 25% — and CO[font size=1]2[/font] responsible for 20% of the effect. The remainder is made up with the other minor greenhouse gases, ozone and methane for instance, and a small amount from particles in the air (dust and other "aerosols"
.
Given that CO[font size=1]2[/font] has such a major role in the natural greenhouse effect, it makes intuitive sense that changes in its concentration because of human activities might significantly enhance the greenhouse effect. However, calculating the impact of a change in CO[font size=1]2[/font] is very different from calculating the current role with respect to water vapor and clouds. This is because both of these other substances depend on temperatures and atmospheric circulation in ways that CO[font size=1]2[/font] does not. For instance, as temperature rises, the maximum sustainable water vapor concentration increases by about 7% per degree Celsius. Clouds too depend on temperature, pressure, convection and water vapor amounts. So a change in CO[font size=1]2[/font] that affects the greenhouse effect will also change the water vapor and the clouds. Thus, the total greenhouse effect after a change in CO[font size=1]2[/font] needs to account for the consequent changes in the other components as well. If, for instance, CO[font size=1]2[/font] concentrations are doubled, then the absorption would increase by 4 W/m[font size=1]2[/font], but once the water vapor and clouds react, the absorption increases by almost 20 W/m[font size=1]2[/font] — demonstrating that (in the GISS climate model, at least) the "feedbacks" are amplifying the effects of the initial radiative forcing from CO[font size=1]2[/font] alone. Past climate data suggests that this is what happens in the real world as well.
What happens when the trace greenhouse gases are removed? Because of the non-linear impacts of CO[font size=1]2[/font] on absorption, the impact of removing the CO[font size=1]2[/font] is approximately seven times as large as doubling it. If such an event were possible, it would lead to dramatic cooling, both directly and indirectly, as the water vapor and clouds would react. In model experiments where all the trace greenhouse gases are removed the planet cools to a near-Snowball Earth, some 35°C cooler than today, as water vapor levels decrease to 10% of current values, and planetary reflectivity increases (because of snow and clouds) to further cool the planet.
Despite being a trace gas, there is nothing trivial about the importance of CO[font size=1]2[/font] for today, nor its role in shaping climate change in the future.
…[/font][/font]
By Gavin Schmidt — October 2010
[font size=3] Most of us have heard that the greenhouse effect keeps the planet much warmer than it would be otherwise, and similarly we may have heard that increasing amounts of greenhouse gases are enhancing the natural greenhouse effect. But few of us appreciate what exactly it is in the atmosphere that makes the effect work and why small changes in trace gases such as carbon dioxide (CO[font size=1]2[/font]) might make a difference.
It has been understood since the 19th century that some gases absorb infrared radiation (IR) that is emitted by the planet, slowing the rate at which the planet can cool and warming the surface. These so-called greenhouse gases include carbon dioxide and water vapor, as well as ozone and methane among others. Note, however, that the bulk of the atmosphere is made up of nitrogen and oxygen molecules which don't absorb IR at all. Less well appreciated is that clouds (made of ice particles and/or liquid water droplets) also absorb infrared radiation and contribute to the greenhouse effect, too. Clouds, of course, also interfere with incoming sunlight, reflecting it back out to space, making their net effect one of cooling, but their contribution to the greenhouse effect is important.
The size of the greenhouse effect is often estimated as being the difference between the actual global surface temperature and the temperature the planet would be without any atmospheric absorption, but with exactly the same planetary albedo, around 33°C. This is more of a "thought experiment" than an observable state, but it is a useful baseline. Another way of quantifying the effect is to look at the difference between the infrared radiation emitted at the surface of the Earth, and the amount that is emitted to space at the top of the atmosphere. In the absence of the greenhouse effect, this would be zero (in other words, no difference). In actuality the surface emits about 150 Watts per square meter (W/m[font size=1]2[/font]) more than goes out to space.
So of all the greenhouse substances in the atmosphere, which of them absorbs what? This is a more complicated issue than it might first appear because of the nature of the absorption and the complex distribution of absorbers both horizontally and vertically. Different substances absorb different frequencies of IR, and the different parts of the planet differ wildly in how much IR is being emitted (based as it is on surface temperature) and how much cloud and water vapor there is at that location (carbon dioxide is very well mixed). Indeed, some wavelengths of IR can be absorbed by both water vapor or clouds, or water vapor and CO[font size=1]2[/font]. This "spectral overlap" means that if you remove a substance, the change in how much IR is absorbed will be less than if you only had that substance in the air. Alternately, the impact of all the substances together is less than what you would get if you added up their individual components. This needs to be taken into account in any attribution of the greenhouse effect.
[font size=2]
Outgoing spectral radiance at the top of Earth's atmosphere showing the absorption at specific frequencies and the principle absorber. For comparison, the red curve shows the flux from a classic "blackbody" at 294°K (≈21°C ≈ 69.5°F).[/font]
We use the GISS model of radiative transfer through the global atmosphere to try and break down the attribution using realistic distributions of local temperature, water vapor and clouds. By removing each of the absorbers in turn and calculating the absorption for many different combinations, we can calculate all the overlaps and allocate the absorption fairly. We find that water vapor is the dominant substance — responsible for about 50% of the absorption, with clouds responsible for about 25% — and CO[font size=1]2[/font] responsible for 20% of the effect. The remainder is made up with the other minor greenhouse gases, ozone and methane for instance, and a small amount from particles in the air (dust and other "aerosols"
.
[font size=2]
A satellite map of the outgoing longwave radiation emitted by Earth in September 2008 demonstrates not only geographical variations but also those caused by cloud presence. More heat escapes from areas just north and south of the equator, where the surface is warmer and there are fewer clouds. (Image: NASA/Earth Observatory/Robert Simmon from CERES data.)[/font]
Given that CO[font size=1]2[/font] has such a major role in the natural greenhouse effect, it makes intuitive sense that changes in its concentration because of human activities might significantly enhance the greenhouse effect. However, calculating the impact of a change in CO[font size=1]2[/font] is very different from calculating the current role with respect to water vapor and clouds. This is because both of these other substances depend on temperatures and atmospheric circulation in ways that CO[font size=1]2[/font] does not. For instance, as temperature rises, the maximum sustainable water vapor concentration increases by about 7% per degree Celsius. Clouds too depend on temperature, pressure, convection and water vapor amounts. So a change in CO[font size=1]2[/font] that affects the greenhouse effect will also change the water vapor and the clouds. Thus, the total greenhouse effect after a change in CO[font size=1]2[/font] needs to account for the consequent changes in the other components as well. If, for instance, CO[font size=1]2[/font] concentrations are doubled, then the absorption would increase by 4 W/m[font size=1]2[/font], but once the water vapor and clouds react, the absorption increases by almost 20 W/m[font size=1]2[/font] — demonstrating that (in the GISS climate model, at least) the "feedbacks" are amplifying the effects of the initial radiative forcing from CO[font size=1]2[/font] alone. Past climate data suggests that this is what happens in the real world as well.
What happens when the trace greenhouse gases are removed? Because of the non-linear impacts of CO[font size=1]2[/font] on absorption, the impact of removing the CO[font size=1]2[/font] is approximately seven times as large as doubling it. If such an event were possible, it would lead to dramatic cooling, both directly and indirectly, as the water vapor and clouds would react. In model experiments where all the trace greenhouse gases are removed the planet cools to a near-Snowball Earth, some 35°C cooler than today, as water vapor levels decrease to 10% of current values, and planetary reflectivity increases (because of snow and clouds) to further cool the planet.
Despite being a trace gas, there is nothing trivial about the importance of CO[font size=1]2[/font] for today, nor its role in shaping climate change in the future.
…[/font][/font]
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