This one is for Silke (from the Jet Propulsion Lab, via Hot Air)
Long-term climate records are a key to understanding how Earth's climate changed in the past and how it may change in the future. Direct measurements of light energy emitted by the sun, taken by satellites and other modern scientific techniques, suggest variations in the sun's activity influence Earth's long-term climate. However, there were no measured climate records of this type until the relatively recent scientific past.
Amazing. To actually think that the big ball that hangs in the daytime sky, and is, incidently, bright enough to blind us, could have an influence on the climate.
Alexander Ruzmaikin and Joan Feynman of NASA's Jet Propulsion Laboratory, Pasadena, Calif., together with Dr. Yuk Yung of the California Institute of Technology, Pasadena, Calif., have analyzed Egyptian records of annual Nile water levels collected between 622 and 1470 A.D. at Rawdah Island in Cairo. These records were then compared to another well-documented human record from the same time period: observations of the number of auroras reported per decade in the Northern Hemisphere. Auroras are bright glows in the night sky that happen when mass is rapidly ejected from the sun's corona, or following solar flares. They are an excellent means of tracking variations in the sun's activity.
The study covered a period from before the Global Climate Optimum, also known as the Medieval Warm Period, into the Little Ice Age.
The researchers found some clear links between the sun's activity and climate variations. The Nile water levels and aurora records had two somewhat regularly occurring variations in common – one with a period of about 88 years and the second with a period of about 200 years.
So the Sun can actually cause warming. Hard to imagine that a giant nuclear furnace responsible for keeping the Earth from becoming a ball of ice could actually, you know, go through phases that warm and cool the Earth.
So what causes these cyclical links between solar variability and the Nile? The authors suggest that variations in the sun's ultraviolet energy cause adjustments in a climate pattern called the Northern Annular Mode, which affects climate in the atmosphere of the Northern Hemisphere during the winter. At sea level, this mode becomes the North Atlantic Oscillation, a large-scale seesaw in atmospheric mass that affects how air circulates over the Atlantic Ocean. During periods of high solar activity, the North Atlantic Oscillation's influence extends to the Indian Ocean. These adjustments may affect the distribution of air temperatures, which subsequently influence air circulation and rainfall at the Nile River's sources in eastern equatorial Africa. When solar activity is high, conditions are drier, and when it is low, conditions are wetter.
But the majority of what is causing that wopping 1 degree Celcius change upward over the past 150 years couldn't possibly be the Sun now, could it? Has to be Mankind. Because otherwise, the global warming as caused by Mankind zealots could push to destroy the developed countries industrial bases, and make lots of money themeselves while pushing it, but not living the life. Just ask Al "I own several non global warming friendly houses, take limo's, fly all over the world, and owned a zinc mine" Gore.
More: Info on the Sun:
- The Sun's output is not entirely constant. Nor is the amount of sunspot activity. There was a period of very low sunspot activity in the latter half of the 17th century called the Maunder Minimum. It coincides with an abnormally cold period in northern Europe sometimes known as the Little Ice Age. Since the formation of the solar system the Sun's output has increased by about 40%.
- In what could be the simplest explanation for one component of global warming, a new study shows the Sun's radiation has increased by .05 percent per decade since the late 1970s
- The sun's energy output is 386 billion megawatts each second, this is caused by the process of nuclear fusion.
- the Sun's energy output is equivalent to about 4 trillion trillion 100 watt light bulbs!
Interesting.
Damn denialists! They’ll go to any extreme to prove Algore wrong. Even to the Nile.
Seriously, great little piece of information. But will it make the light of day in the MSM? This should be front page news and must be seriously considered before we slit our own economic throats on the jagged sword of Man Made Global Warming.
What chutzpah to think the world, nay the universe, revolves around man.
Teach, I’m not aware of any scientist who disputes the fact that the sun influences our climate. The question is whether the sun is the cause of the current warming trend and there was nothing in this report that suggests that. In fact this paper (linked below) by Damon and Laut shows that solar activity for the past fifty years does not correspond with the rise in average temperatures (see Figure 2).
http://stephenschneider.stanford.edu/Publications/PDF_Papers/DamonLaut2004.pdf
Incidentally, you stated in an earlier post that “the 30’s were warmer then it is todayâ€. Where did you get this information? According to figure SPM-3(Global average temperature) on page 6 of the IPCC’s Fourth Assessment Report Summary for Policymakers, that’s not correct.
http://www.ipcc.ch/SPM2feb07.pdf
Wikipedia also shows a graph of the instrumental temperature record which is different from your statement:
http://en.wikipedia.org/wiki/Image:Instrumental_Temperature_Record.png
Sorry for the double comment. Could you please remove one?
Right, because if the Sun had anything to do with it, as it has throughout history, that would invalidate the talking points that Mankind is the cause, so we should all immediately change how we live to the detriment of big business.
Or, we can play silly little games and buy “credits,” like Al Gore.
Sorry, but I refuse to listen to those, like AL Gore, who refuse to live the life they want everyone else to.
Teach, how does this article relate to the current debate on climate change? Nobody disputes the fact that the sun is a factor, it’s just not the cause of the current warming trend. Also, where did you get your information that “the 30’s were warmer than it is todayâ€.
Right, because the Sun couldn’t possibly have anything to do with this subject, despite being the primary driver of most every cool and hot spell in the history of the planet. That would be inconvenient to the the politics of global warming as caused by man.
Are you living the carbon neutral life?
As far as the 30’s goes, I do not see anything in the article about it. However, why not look up what the temps were in the 1930’s? I think you might be surprised.
Teach, if you look at the IPCC’s summary they have factored in the sun and it is not believed to be the cause of the current warming trend.
Regarding the temps in the 30’s, I was referring to an earlier post of yours where you stated that it was warmer in the 30’s than it is today. The links I provided above show that’s false. Here they are again:
Page 6 figure SPM-3 (Global average temperature)
http://www.ipcc.ch/SPM2feb07.pdf
http://en.wikipedia.org/wiki/Image:Instrumental_Temperature_Record.png
You know, quoting the IPCC’s report as gospel is not very good. There are so many fudged factors in the methods used to estimate out comes for the multitude of variables that none of the computer models produced so far can duplicate the findings. Several of the scientists initially linked to the project have bailed and the data of others has been cobbled together by a “committee”–never a good idea.
So, again, do we really want to slit our own economic throats over a piece of “research” that is gathering more scientific opponents as the days pass?
“Teach, if you look at the IPCC’s summary they have factored in the sun and it is not believed to be the cause of the current warming trend.”
“Not believed.” Ah, more of that deep scientific research in that political document. Science involves facts, not conjecture, and certainly not politics.
How is it possible that natural forces play no part, when the little ice age ended in the mid 1850’s, and the temps started going up? How many cars were there back then?