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
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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
“We may have a lot more to learn about how solar variability works, and how the sun might influence our climate,” Cahalan said.
That’s a huge understatement. When are these people going to get with the program and learn to start out with what you don’t know before you try and wax about what little you do?
As Piers Corbyn consistently forecasts seasonal U.K. weather conditions to 85% accuracy [see London Mayor Boris Johnson’s recent commentary], a “structured top-down” approach using historical sunspot data available over 400 years trumps “bottom-up” Met Office fiddle-diddle every time.
Since Edward Lorenz originated Chaos Theory c. 1964, elaborated by Benoit Mandelbrot’s Fractal Geometry a decade later, climatologists have systematically ignored the fact that complex dynamic systems (components exceeding three elements) are non-random but indeterminate, unforeseeable not due to esoteric statistical artifacts amenable to super-computer resolution but to an ineluctable “butterfly effect” whereby “sensitive dependence on initial conditions” plus self-similarity on every scale renders detailed extrapolations meaningless.
Despite Lorenz and Mandelbrot, however, long-term climate cycles, patterns, remain largely foreseeable. Over some 2.6 million years to date, recurrent Pleistocene glaciations have averaged 102,000 years, separated by interglacial remissions of median 12,250 years. Continental ice-sheets began thinning some 14,400 years before present (YBP), inducing our current Holocene Interglacial Epoch which if not for an anomalous 1,500-year Younger Dryas “cold shock” would have ended about AD 450, coincident with the Fall of Rome.
Whether recent solar inactivity presages a 40-year “dead sun” Dalton Minimum similar to that of 1790 – 1830 or a 70-year Maunder Minimum analogous to 1645 – 1715, when Louis XIV’s wine glazed over in his Palace of Versailles, geophysical history strongly hints a pending regression to Ice Time. Warmists’ fixation on ignorant and genuinely stupid AGW reflects a societal death-wish akin to that of murderous jihadi terrorists whose vicious “1010” mindset such power-hungry elitists’ academic-bureaucratic-political Iron Triangle will stop at nothing to endorse.
Scooter says
A) TSI is ‘assumed’ constant so some folks say there is no impact on climate
—————-
TSI is measured to be constant; no assumptions required.
Wilky says:
December 22, 2010 at 8:08 am
Bravo! You got it buddy! It’s Max Planck…..
John Blake says:
December 22, 2010 at 8:29 am
Since Edward Lorenz originated Chaos Theory c. 1964, elaborated by Benoit Mandelbrot’s Fractal Geometry a decade later, climatologists have systematically ignored the fact that complex dynamic systems (components exceeding three elements) are non-random but indeterminate, unforeseeable not due to esoteric statistical artifacts amenable to super-computer resolution but to an ineluctable “butterfly effect” whereby “sensitive dependence on initial conditions” plus self-similarity on every scale renders detailed extrapolations meaningless.
This is wrong: There are laws in nature. Randomness it is a justification of ignorance, an argument for the politician to cheat the fool, or an elaborated lie by a conspirator, but never science.
You choose: Jump into an abyss and save yourself by randomness.
“anna v says:
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.”
============================================
So back to the graph.
1. Supposing the 0-axis is: ‘Solar Irradiation in 2004’.
The black line: ‘EXPECTED difference in spectral irradiance from 2004 to 2007’.
The blue line: ‘MEASURED difference in spectral irradiance from 2004 to 2007’.
While a decrease was expected, the black line gives positive values.
So, the best interpretation of the graph seems that the black line gives ‘the AMOUNT OF DECREASE in spectral irradiation from 2004 to 2007’.
The graph thus shows much more decrease in UV than expected and a slight increase in visible light.
2. Leif’s statement, that a decrease was expected and an increase was measured, creates a problem.
Whatever the vertical axis exactly means, an increase and a decrease in UV should be on opposing sides of the 0-line.
What do I miss here?
Wilky, quantify the reduction. Let me see the maths. And let’s be precise. You mean “…at the outer most edge of Earth’s atmosphere”. What gets to the top of our heads is a whole nother set of maths with so many variables you would run out of letters in the expression.
OK, the caption above is confusing.
Ffrom the figures in the publication, accompanying the abstract the description of the first plot reads:
The difference (2004–2007) in solar spectral irradiance (W m−2 nm−1) derived from SIM data4 (in blue), SOLSTICE data8 (in red) and from the Lean model5 (in black). Different scales are used for values at wavelengths less and more than 242 nm…
Now the plot can be understood as consistent with diminishing UV since it is the difference between two dates (2004 -2007) and not the usual anomalies we have been perverted by climate scientists to expect. Positive means 2007 is less than 2004.
So I see a conflict with the plots Leif supplied above, which show an increase in UV in the same interval for some part of the spectrum, if I am reading them correctly.
Lets ask the plankton.
“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.
Where I am from, data trumps models any day. This example illustrates the problem with climate science, Data Doesn’t Matter!
One thing very important in this statement is the revaluation that the climate models take into account solar activity. I have never seen any reference in climate modeling that shows the effects of the Solar Cycle. We are told over and over that the sun does not matter! When did this change and now solar variability is part of the global climate equation? Every climate model I have seen, showed an increase in global temp through the solar cycles without even a blip. So now the sun is important? Who knows maybe next it will be cloud cover, solar magnetic fields, or cosmic radiation ….. one can only hope.
Re: ““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.”
Ad hoc modeling is great for public relations, but in science, theorists are supposed to also consider competing models when they observe such a fundamental error in their model.
Re: “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.”
This is the characteristic behavior of the plasma glow discharge in the laboratory. This is what a Crooks Tube with a spherical geometry will do when the current density (delivered by an electron drift) is altered. Increase or decrease the current density, which we would observe as an increase in the magnetic field, and you can expect the spectra to change.
We all intuitively know, without any scientific degree, that as you pass electrical current through an object, its temperature and color will change. It is the thermonuclear core model for the Sun which distracts people from latching onto the simplest inference.
The entire HR diagram is a contorted view of the fundamental operating modes of a plasma. This diagram’s axes are misleading. Don Scott explains the minor tweaks necessary to convert the HR diagram into a plot of plasma’s fundamental operating modes, and illustrates how this slight adjustment resolves numerous stellar observations which are enigmatic to the conventional thermonuclear model:
http://www.electric-cosmos.org/hrdiagr.htm
But, of course, a person would have to concern themselves with the observed behavior of laboratory plasmas in order to fully grasp how simple this competing model is. A person has to be willing to imagine that conventional theory is wrong before they can grasp the link between the Sun and plasma physics fundamentals.
Ultimately, what’s most compelling about the electric sun model is that the model can be tested against the observed behavior of a glow discharge, as explained within engineering textbooks — like JD Cobine’s “Gaseous Conductors”.
Those who take the time to pursue this avenue of investigation will find that the Sun’s behavior can be fully explained with laboratory plasma physics. Arguments that we cannot see the Sun’s power source — its electron drift — are disingenuous because measuring an electron drift would not be a simple matter to begin with.
The decision to completely ignore the fact that we can create a completely functional and new solar model — an electric sun model — as Don Scott has attempted to do, is a decision which will ultimately come to haunt conventional thinkers. This is time lost for all of us, guys. We’re spinning our wheels, for the sole reason that the theorists are preferring certain inferences over others.
The public expects these models to be built. They do not care who started the work. They want functional, predictive solar models — not ad hoc models. And so long as theorists continue to ignore the vital role that this electron drift plays, as evidenced by the magnetic field which they observe, the solar models will continue to perplex them.
LazyTeenager says:
December 22, 2010 at 8:45 am
“Scooter says
A) TSI is ‘assumed’ constant so some folks say there is no impact on climate
—————-
TSI is measured to be constant; no assumptions required.”
Sometimes your laziness seems to get the upper hand, LazyTeenager.
http://en.wikipedia.org/wiki/Solar_variation
Robin Kool says:
December 22, 2010 at 3:46 am
Did UV decrease or increase?
The graph shows the difference between UV in 2007 and 2004. This difference is positive, hence UV [the near UV not the extreme UV] increased from 2004 to 2007.
Richard P says:
December 22, 2010 at 9:32 am
I have never seen any reference in climate modeling that shows the effects of the Solar Cycle. We are told over and over that the sun does not matter! When did this change and now solar variability is part of the global climate equation? Every climate model I have seen, showed an increase in global temp through the solar cycles without even a blip.
Solar activity has always been in the climate models. That you haven’t seen this is because you haven’t looked. The reason you haven’t heard much about it is that the influence of the Sun is so small [but definitely there] that it doesn’t make any significant difference compared to the other changes.
The North Magnetic Pole was at 81.3°N 110.8°W in 2001. In 2010, it is located at 84.97°N and 132.35°W. It has been reported that the wandering pole is moving toward Russia at 40 miles per year.
Since earth’s magnetic north and dynamic core are shifting and these are tied to the sun’s magnetic field and orbital forcing, it would seem that regional climate would change to due to the changes in the position of magnetic north. Europe and parts of Asia will be closer to magnetic north and become colder as it advances to Siberia.
Any thoughts?
http://news.nationalgeographic.com/news/2009/12/091224-north-pole-magnetic-russia-earth-core.html
“We may have a lot more to learn about how solar variability works, and how the sun might influence our climate,” Nah ya dont, the IPCC said it doesnt affect the climate, now move along…
If the extra UV warms the stratosphere, what does that do to surface temps?
Leif Svalgaard says:
December 22, 2010 at 9:59 am
The graph shows the difference between UV in 2007 and 2004. This difference is positive, hence UV [the near UV not the extreme UV] increased from 2004 to 2007.
On the other hand, the NASA release states:
“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.”
This is the opposite of the graph so no wonder there is some confusion…
I’m trying myself to make sense of the various graphs that Jerry Harder presents. Here are some more: http://www.agci.org/dB/PPTs/10S1_0615_JHarder.pdf [see slide 6]
Like, what is the interpretation of ‘difference between 2004 to 2007’ ?
The obvious one is difference = value in 2007 – value in 2004. But what if they actually mean difference = value in 2004 – value in 2007 ? If they mean that, then there would be nothing earth-shaking about the UV, it just behaved as expected. What do y’all think?
Leif has mentioned this solar inclusion model fact several times on WUWT in the past. Thanks to his generous sharing and suggested links from several others, most of us who read up on these things have known that solar influences are part of computer climate models. The models I think have this one right. Not so much other parameters and variables though.
———————-
Leif,
I note the overall picture of SSI magnitude is shown on Page 4 of the presentation of the paper by Harder et al (http://lasp.colorado.edu/sorce/news/2010ScienceMeeting/doc/Session3/3.02_Harder_SSI.pdf )
I take from Harder,
1) They use SSI data from SIM for period of 4 years , mid 2004 to mid 2009
2) The 4 yr period corresponds mostly to the a declining portion of SC 23 and the extended minimum between SC 23 & 24 as follows:
a. Begins at almost midpoint in the decline of SC 23 from maxima
b. Ends at about 6 months after the minima between SC 23 and SC 24
3) My take over this period is the delta SSI for various solar wavelength bands are:
a. Delta SSI due to UV is approximately: -1.0 Watts per m squared
b. Delta SSI due to VIS is approximately: +0.7 “ “ “ “
c. Delta SSI due to NIR is approximately: +0.3 “ “ “ “
d. Approximate Total delta SSI: 0.0
Therefore, the inference from the main post article “SORCE’s Solar Spectral Surprise – UV declined, TSI constant” that from 2004 to 2007 UV increased seems to be at odds with Harder et al.
So I am slightly confused.
John
Leif Svalgaard says:
December 22, 2010 at 10:03 am
The reason you haven’t heard much about it is that the influence of the Sun is so small [but definitely there] that it doesn’t make any significant difference compared to the other changes.
WOW!…so that shiny round thing above us in the sky it is just an ornament?
Leif Svalgaard says:
December 22, 2010 at 10:03 am
The reason you haven’t heard much about it is that the influence of the Sun is so small [but definitely there] that it doesn’t make any significant difference compared to the other changes.
Leif, that is because the models only take into account the TSI/4 changes and assume that 1 W/m2 change in insolation has the same effect as 1 W/m2 change in IR absorption by CO2. But solar (UV) has effects in the stratosphere, including changes in jet stream position (clouds, rain patterns), not seen by increased GHGs, and an inverse correlation with low cloud cover (whatever the mechanism behind it). Thus the influence may be much more than currently implied in the climate models. Some interesting literature:
http://www.agu.org/pubs/crossref/2005/2005GL024393.shtml
or subscription free:
http://www.somas.stonybrook.edu/downloads/pubs/hameed/HameedLee.pdf
“We may have a lot more to learn . . . ”
If only more scientists believed that. Hubris is a large part of the problem with science these days.
It my interesting highly opinionated observation, over the course of reading many climate blogs, that the warm-earther theorists (aka “modelers”) seem to always dismiss instrumental data that does not agree with their speculations (that’s what a model really involves, after all — unsubstantiated speculation in search of grant money) as being due to a fault of the instrument. Although it is likely, on the other hand, that the Establishment’s instruments are usually set up to measure those parameters that are called for to substantiate said models.
Same old, same old.
My conclusion: Let’s defund the suckers.
I think I’m right in saying that the level of solar activity is in the models just as Leif says but it is limited to simple TSI which changes hardly at all.
What is not in the models is any accurate representation of changes in the composition of photons, wavelengths and particles coming from the sun. That is what this article is just beginning to consider.
Nor any representation of the variable atmospheric responses to changes in that composition over long periods of time.
Nor any representation of differential warming and cooling at different levels in the atmosphere attributable to such changes in composition.
Nor any representation as to how the net latitudinal position of the air circulation systems changes beyond normal seasonal variability over multiple decades or centuries.
Nor any direct link between the size and intensity of the polar vortices in response to those changes in composition.
So there is lot to play for and a lot of unsettled science.