From NASA’s website (h/t to David Archibald)
By Adam Voiland
NASA’s Earth Science News Team
Two satellite instruments aboard NASA’s Solar Radiation & Climate Experiment (SORCE) mission — the Total Solar Irradiance Monitor (TIM) and the Solar Irradiance Monitor (SIM) — have made daily measurements of the sun’s brightness since 2003.
The two instruments are part of an ongoing effort to monitor variations in solar output that could affect Earth’s climate. Both instruments measure aspects of the sun’s irradiance, the intensity of the radiation striking the top of the atmosphere.
Instruments similar to TIM have made daily irradiance measurements of the entire solar spectrum for more than three decades, but the SIM instrument is the first to monitor the daily activity of certain parts of the spectrum, a measurement scientists call solar spectral irradiance.
In recent years, SIM has collected data that suggest the sun’s brightness may vary in entirely unexpected ways. If the SIM’s spectral irradiance measurements are validated and proven accurate over time, then certain parts of Earth’s atmosphere may receive surprisingly large doses of solar radiation even during lulls in solar activity.
“We have never had a reason until now to believe that parts of the spectrum may vary out of phase with the solar cycle, but now we have started to model that possibility because of the SIM results,” said Robert Cahalan, the project scientist for SORCE and the head of the climate and radiation branch at NASA’s Goddard Space Flight Center in Greenbelt, Md.
Cahalan, as well as groups of scientists from the University of Colorado at Boulder and Johns Hopkins University, presented research at the American Geophysical Union meeting in San Francisco in December that explored the climate implications of the recent SIM measurements.
Cahalan’s modeling, for example, suggests that the sun may underlie variations in stratospheric temperature more strongly than currently thought. Measurements have shown that stratospheric temperatures vary by about 1 °C (1.8 °F) over the course of a solar cycle, and Cahalan has demonstrated that inputting SIM’s measurements of spectral irradiance into a climate model produces variations of that same magnitude.
Without inclusion of SIM data, the model produces stratospheric temperature variations only about a fifth as strong as would be needed to explain observed stratospheric temperature variations. “We may have a lot more to learn about how solar variability works, and how the sun might influence our climate,” Cahalan said.
Measuring Variation
As recently as the 1970s, scientists assumed that the sun’s irradiance was unchanging; the amount of energy it expels was even called the “solar constant.” However, instruments similar to TIM and SIM have made clear that the sun’s output actually fluctuates in sync with changes in the sun’s magnetic field.
Indeed, TIM and its predecessor instruments, whose records of irradiance began in 1978, show that the sun’s output varies by about 0.1 percent as the sun cycles through periods of high and low electromagnetic activity every eleven years or so. In practice, this cycling means the sun’s brightness, as measured by TIM, goes up a bit when large numbers of sunspots and accompanying bright spots called faculae are present on the sun, yet goes down slightly when sunspots and faculae are sparse, like they have been in the last few years as the sun has gone through an unusually quiet period.
However, there is a critical difference between the SIM and TIM, explains Jerry Harder, the lead SIM instrument scientist and a researcher at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado in Boulder. While the TIM lumps all wavelengths — including infrared, visible, and ultraviolet light — into one overall measurement, the SIM isolates and monitors specific portions of the spectrum.
Notably, this makes SIM the first space-based instrument capable of continuously monitoring the visible and near-infrared portion, parts of the spectrum that are particularly important for the climate. SIM also offers the most comprehensive view of the individual components that make up the sun’s total solar irradiance to date.
Some of the variations that SIM has measured in the last few years do not mesh with what most scientists expected. Climatologists have generally thought that the various part of the spectrum would vary in lockstep with changes in total solar irradiance.
However, SIM suggests that ultraviolet irradiance fell far more than expected between 2004 and 2007 — by ten times as much as the total irradiance did — while irradiance in certain visible and infrared wavelengths surprisingly increased, even as solar activity wound down overall.
The steep decrease in the ultraviolet, coupled with the increase in the visible and infrared, does even out to about the same total irradiance change as measured by the TIM during that period, according to the SIM measurements.
The stratosphere absorbs most of the shorter wavelengths of ultraviolet light, but some of the longest ultraviolet rays (UV-A), as well as much of the visible and infrared portions of the spectrum, directly heat Earth’s lower atmosphere and can have a significant impact on the climate.
Climate Consequences?
Some climatologists, including Judith Lean of the United States Naval Research Laboratory, Washington, remain skeptical of the SORCE SIM measurements. “I strongly suspect the SIM trends are instrumental, not solar,” said Lean, noting that instrumental drift has been present in every instrument that has tracked ultraviolet wavelengths to date.
“If these SIM measurements indicate real solar variations, then it would mean you could expect a warmer surface during periods of low solar activity, the opposite of what climate models currently assume,” said Gavin Schmidt, a climate modeling specialist at NASA’s Goddard Institute for Space Studies in New York City.
It would also imply that the sun’s contribution to climate change over the last century or so might be even smaller than currently thought, suggesting that the human contribution to climate change may in turn be even larger than current estimates.
However, the surprising SIM measurements correspond with a period of unusually long and quiescent solar minimum that extended over 2007 to 2009. It may not be representative of past or future solar cycles, solar scientists caution.
Researchers will surely continue puzzling over the surprising SIM results for some time, but there is already considerable agreement on one point: that the need for continuous SIM and TIM measurements going forward has grown more urgent.
Modeling studies are showing that our climate depends critically on the true solar spectral variations. “If we don’t have the instruments up there to watch this closely, we could be arguing about spectral irradiance and climate for decades,” said Cahalan.
A new TIM instrument is slated to launch on the Glory satellite this February, but a replacement for the SORCE SIM instrument — called the Total and Spectral Solar Irradiance Sensor (TSIS) — likely won’t fly until 2014 or 2015. This could create a gap between the current SIM and its replacement, a situation that would present a significant obstacle to identifying any possible longer-term trend in solar spectral irradiances, and thus to nailing down the sun’s role in long-term climate change.
“Both instruments — TIM and SIM — are absolutely critical for understanding how climate works. We neglect either of them at our peril,” said Cahalan.
Solar activity – including sunspots and accompanying bright areas called faculae – vary over the course of a solar cycle and affect solar irradiance. Credit: NASA
Related Links:
SORCE Website
http://lasp.colorado.edu/sorce/index.htm
AGU Session: Solar Variability and Climate
http://www.agu.org/cgi-bin/sessions5?meeting=fm10∂=GC13E&maxhits=400
=====================================================================
Additional information:
Leif Svalgaard writes in email:
This is legit.
It is a confusing graph. It shows how much the spectral emission has
changed between 2004 and 2007. Since solar activity was decreasing one
expected UV to decrease. Instead it increased. The increase was offset
by a decrease in IR, leaving TSI almost constant. That the near UV
goes up when solar activity goes down I pointed out some time ago
[before the LASP people noticed it], see the lower two panels of
http://www.leif.org/research/Erl70.png (provided below)
There are all kinds of ramifications, see the talks in Session 4 at:
http://lasp.colorado.edu/sorce/news/2010ScienceMeeting/agendas.html#speakers
Interesting, considering that strong UV stimulates plankton to create clouds according to another NASA publication
The study finds that in summer when the Sun beats down on the top layer of ocean where plankton live, harmful rays in the form of ultraviolet (UV) radiation bother the little plants. UV light also gives sunburn to humans.
When plankton are bothered, or stressed by UV light, their chemistry takes over.
……
DMS then filters from the ocean into the air, where it breaks down again to form tiny dust-like particles. These tiny particles are just the right size for water to condense on, which is the beginning of how clouds are formed. So, indirectly, plankton help create more clouds, and more clouds mean that less direct light reaches the ocean surface. This relieves the stress put on plankton by the Sun’s harmful UV rays.
A contribution to albedo similar to the effect expected from galactic cosmic rays.
So the answer to Gavin is to hold his horses and ask the plankton.
ASSUME – a word that makes an ASS of U and ME
Tom Woods might be the man to watch, he presented at the May conference that Leif promotes. He concentrates on the Extreme UV wave lengths which show a marked decline compared with the last minimum.
Low EUV is responsible for our record low Thermosphere, which may be the trigger for the current observed negative AO & NAO oscillations.
“W Abbott says:
December 22, 2010 at 4:18 am
Robin is right, I can’t reconcile Leif’s comment with the graph. I also don’t understand why a decrease in the shortest UV wavelengths would increase Stratospheric warming or O3 quantities above 45km. Stephen Wilde, I think hits the nail on the head, but I don’t understand the mechanism in the upper stratosphere. Can you explain Stephen?”
I can only refer you to this and hope I’m not boring those who have already seen it:
http://climaterealists.com/index.php?id=6645
“How The Sun Could Control Earth’s Temperature”
with the proviso that I think it goes beyond solar protons on their own.
W Abbott says:
December 22, 2010 at 4:18 am
Robin is right, I can’t reconcile Leif’s comment with the graph.
Yes it is confusing. The plot shows positive differences for the UV region and negative for the infrared, and agrees with Leif’s plots. The explanation says the opposite, decrease in UV and increase in IR. Very sloppy in either case.
If we are to vote, I vote for Leif’s explanation.
John A says:
December 22, 2010 at 2:12 am
“Am I the only person to see that Gavin Schmidt’s response is a non sequitur to the data presented?”
Gavin is a always good for a ‘it’s worse then we thought quote’.
Lee Kington:
‘If the SIM measurements were correct thus the assumptions installed in the models incorrect then the affect attributed to those assumptions would need be attributed to another influence. ‘
Colour (or color if you prefer) me confused as well. Please check your English before hitting ‘post comment’?
By the way, you mean ‘effect’ not ‘affect’.
The Gavinian Task (aka The Sisyphean Task):
“If these SIM measurements indicate real solar variations, then it would mean you could expect a warmer surface during periods of low solar activity, the opposite of what climate models currently assume,” ………..said Gavin Schmidt
Step 1: Maintain that the science is settled.
Step 2: Use computer models of climate as the summum bonum of climate science.
Step 3: Recognize new research in the real world conflicts with model assumptions.
Step 4: Skip next step.
Step 5: Announce planned revisions to computer model (summum bonum).
Step 6: Avoid questions about Step 5.
Step 7: Bash “Deniers.”
Step 8: Incorporate new research in climate model & interpret it as supporting AGW.
Step 9: Maintain that the science is settled.
Stephen Wilde says:
December 22, 2010 at 5:41 am
………..
What happens in upper stratosphere is important, I’d say very important.
Polar vortex in the Arctic often is split up, and this appears to affect not only stratosphere but troposphere too. In contrast the Antarctica’s vortex is pretty solid, only one case of sudden stratospheric warming SSW was recorded since 1950 (in 2002, science is puzzled by the event, but there is an explanation for it).
Polar vortex is frequently (but not all the time) under the influence of the geomagnetic field, I suspect it depends on the extent of ionisation.
http://www.vukcevic.talktalk.net/MF-PV.htm
Leif, can you or anyone else comment on this?
Prof. Haigh has previously authored journal articles suggesting that the way the sun influences climate is that at solar minima (and likely longer periods of inactivity as well) there is a greater reduction in UV than in total radiation. This reduction causes less ozone to be created in the stratosphere, which in turn makes the stratosphere marginally cooler. In turn, this allows cooler weather from the poles to drift a bit toward the equator, thus causing an overall cooling for the earth as a whole.
It seems that this new evidence contradicts the earlier idea. Now, it seems, we have MORE UV when the sun in inactive. If Haigh’s earlier idea is accurate — and I may well not understand her work well enough — then we should have been seeing WARMING in the stratosphere and a warming earth. But the satellite measures don’t show warming.
So either Haigh’s first theory is wrong; or the new measurements are wrong; or there is another mechanism going on — perhaps for some reason the increased ozone might cause more cloudiness, thus causing COOLING?
This is real science, and real science goes through periods of confusion before what is happening is more fully understood. Or maybe it’s just me that doesn’t understand. I’d like to hear from some experts on there three possibilities just noted.
anna v said at 5:45 am
If we are to vote, I vote for Leif’s explanation.
Second! All in favor?
Also I vote we always assume Gavin Schmidt’s responses to be lame assumptions.
I’m gobsmacked by:
If I read this right it was known fact that the stratosphere varied by 1C over a sunspot cycle. At the same time the vaunted GCMs only produced 0.2C of stratosphere variation.
Ahem. The model was then known to be flawed before the SIM data became available by the mere fact that measured stratospheric temperature change didn’t agree with modeled output.
Must be another one of those travesties that don’t make it onto the IPCC sheeple summary.
Leif-
I told you about a year ago on a different board that you guys were clueless as to what was really happening on the sun, and your models reminded of the human genome scientists before the genome were sequenced (I was one – we were wrong on many fundamental points). Solar guys will be proved wrong again and again over the coming decade, I expect. Nothing like data.
To use a political analogy “It’s the sun, stupid!”
At the beginning of the computational era, computers were a good thing for kids, as they had to write their own programs and it helped them, for example, to learn the Pythagoras Theorem while writing a program to solve the equation of that theorem.
However, now, they have stopped thinking because everything is already done, so with X-Box, Twii, or whatever games, pornography, etc all these gadgets are like drugs for kids, specially for these Nasa kids.
Of course.. no-one knows..
The people with agenda launch themselves on the unknown..
The science is definitely NOT settled!
What if..
What if.. human beings thoughts.. change the magnetic field of the earth..
What if.. this then changes the effect of the sun on the earth..
Annomalies are fascinating.
We do not know everything.. and to admit that is a good first step in science.
I am suggesting something quite radical for science.
What if we are not victims to a system we do not understand..
but rather.. the ultimate power..
A study of earth magnetics may show us something, at present, quite unbelievable.
“John says:
December 22, 2010 at 6:26 am”
John raises various good questions to which I would reply as follows:
What seems to be happening is that there is a disjunction in the ozone responses at around 45km. Below that level ozone does indeed decline when the sun is quiet as expected. Above that level ozone increases which is unexpected.
That disjunction can be resolved if one acknowledges ozone creation as declining in the lower levels (ozone reducing) when the sun is quiet whilst ozone destruction declines in the higher levels (ozone increasing) when the sun is quiet. That produces the observed data.
Now more ozone is associated with warming so in theory those changes should give cooling below 45km but they do not.
I have previously posted a link that says that the stratosphere overall stopped cooling in the mid 90s and may now be warming slightly despite the decreasing ozone below 45km.
That issue can be resolved by proposing that the processes above 45km are dominant (now more ozone and so warming) with the result that the levels below 45km are forced to warm up too despite the reducing ozone below 45km.
The opposite when the sun is more active.
All that fits observations perfectly and provides the necessary reverse sign response to solar forcing to cause equatorward shifting jets (requiring a warmer stratosphere) when the sun is quieter.
The shifting of the jets then alters cloud amounts and albedo to change the amount of energy entering the oceans and thereby skew the El Nino/La Nina dominance in favour of net warming or net cooling of the troposphere.
Interesting factoid: OZONE IS ALWAYS FORMED IN THE UPPER ATMOSPHERE AS HIGH ENERGY UV HITS IT!
Thus the “ozone hole” is ONLY a matter of degree, not actual dissapearance of Ozone.
AND, if you look at standard Meteorology books, you will find that Ozone and it’s subsquent decay, are part of the energy transfer from the sun into the overall atmosphere, and thus the incoming UV does have an effect.
To whit: If the UV goes down, less energy into the ATM, goes up, more.
So indeed the total solar irradiance needs to account for all of these.
Max
“If these SIM measurements indicate real solar variations, then it would mean you could expect a warmer surface during periods of low solar activity, the opposite of what climate models currently assume,” said Gavin Schmidt, a climate modeling specialist at NASA’s Goddard Institute for Space Studies in New York City.
It would also imply that the sun’s contribution to climate change over the last century or so might be even SMALLER than currently thought, suggesting that the human contribution to climate change may in turn be even larger than current estimates.
Why just the last century,
http://i446.photobucket.com/albums/qq187/bobclive/400yearsofsunspots.gif
Robinson says:
December 22, 2010 at 2:43 am
You are right: The WHOLE spectrum works, without exceptions. No cherry picking.
Stephen Wilde says:
December 22, 2010 at 1:40 am
My insisting on the following and posted, many times here in WUWT has been fruitful:
What if the water cycle is not closed but opened?. During summer time above the pole and due to increased radiation, atmosphere’s oxygen is turned into Ozone (O3), which during winter time and specially when there are proton flares from the sun or increased cosmic rays, as during solar minimums (mainly composed of protons-90%-, which, btw, we must remember are Hydrogen Nucleii), then these react with ozone to produce water 2H+ O3=H2O+O2 and increase the “Ozone Hole” once again ….
It has been theorized for quite some time that the Sun’s changing influence on the stratosphere is rather readily measured. I can’t see where this is new news. What is important to “feet on the ground” measurements is whether or not stratospheric temperature changes have any influence on the troposphere and our Earth’s quite powerful intrinsic drivers of tropospheric temperatures. My hunch is that Earth’s overwhelmingly stronger and noisier intrinsic mechanisms bury any stratospheric influence in our tropospheric temperature noise.
This is very significant. Higher frequency light carries more energy than lower frequency light, (E=hF) so reductions in UV band light by a factor of 6 results in a sizeable reduction in the amount of solar energy being delivered to the Earth…
vukcevic says:
December 22, 2010 at 6:13 am
You have found the CAUSE, others describe the details and still others their dreams.
I can’t seem to post in Tips… no “leave a reply” field?
http://apnews.myway.com/article/20101221/D9K8JAUG0.html
Transportation experts said that after many years without heavy snowfall, underinvestment has left Heathrow and dozens of other airports across Britain and Ireland without enough equipment or personnel to cope with big storms.
Well, yeah… why would they invest in snowfall equipment when winters in Britain were a “thing of the past?” Unintended consequences of pretending that you know things that you don’t.
Some of you might be interested that DR. Svalgaard only yesterday (on SC24 blog) stated:
I think there will be several low cycles, but this is guesswork.
May be he has come round to recognise value of my formula:
http://www.vukcevic.talktalk.net/LFC11.htm
I doubt it, but you never know.