Posted on 04/10/2007 7:30:56 AM PDT by George W. Bush
Sunspots reaching 1,000-year high
By Dr David Whitehouse
BBC News Online science editor
Sunspots are plentiful nowadays
A new analysis shows that the Sun is more active now than it has been at anytime in the previous 1,000 years.
Scientists based at the Institute for Astronomy in Zurich used ice cores from Greenland to construct a picture of our star's activity in the past.
They say that over the last century the number of sunspots rose at the same time that the Earth's climate became steadily warmer.
This trend is being amplified by gases from fossil fuel burning, they argue.
'Little Ice Age'
Sunspots have been monitored on the Sun since 1610, shortly after the invention of the telescope. They provide the longest-running direct measurement of our star's activity.
The variation in sunspot numbers has revealed the Sun's 11-year cycle of activity as well as other, longer-term changes.
In particular, it has been noted that between about 1645 and 1715, few sunspots were seen on the Sun's surface.
This period is called the Maunder Minimum after the English astronomer who studied it.
Ice cores record climate trends back beyond human measurementsIt coincided with a spell of prolonged cold weather often referred to as the "Little Ice Age". Solar scientists strongly suspect there is a link between the two events - but the exact mechanism remains elusive.
Over the past few thousand years there is evidence of earlier Maunder-like coolings in the Earth's climate - indicated by tree-ring measurements that show slow growth due to prolonged cold.
In an attempt to determine what happened to sunspots during these other cold periods, Dr Sami Solanki and colleagues have looked at concentrations of a form, or isotope, of beryllium in ice cores from Greenland.
The isotope is created by cosmic rays - high-energy particles from the depths of the galaxy.
The flux of cosmic rays reaching the Earth's surface is modulated by the strength of the solar wind, the charged particles that stream away from the Sun's surface.
And since the strength of the solar wind varies over the sunspot cycle, the amount of beryllium in the ice at a time in the past can therefore be used to infer the state of the Sun and, roughly, the number of sunspots.
Latest warming
Dr Solanki is presenting a paper on the reconstruction of past solar activity at Cool Stars, Stellar Systems And The Sun, a conference in Hamburg, Germany.
He says that the reconstruction shows the Maunder Minimum and the other minima that are known in the past thousand years.
But the most striking feature, he says, is that looking at the past 1,150 years the Sun has never been as active as it has been during the past 60 years.
Over the past few hundred years, there has been a steady increase in the numbers of sunspots, a trend that has accelerated in the past century, just at the time when the Earth has been getting warmer.
The data suggests that changing solar activity is influencing in some way the global climate causing the world to get warmer.
Over the past 20 years, however, the number of sunspots has remained roughly constant, yet the average temperature of the Earth has continued to increase.
This is put down to a human-produced greenhouse effect caused by the combustion of fossil fuels.
This latest analysis shows that the Sun has had a considerable indirect influence on the global climate in the past, causing the Earth to warm or chill, and that mankind is amplifying the Sun's latest attempt to warm the Earth.
Well, if you’d lay off bringing in illegals......maybe we’ll accomodate a little warming.
Hey Al the sun beat you to it, now what?
ummm yeah, like I said it was between 1945-1950 that the temperature really dropped and then between 1950-1960 with the "with rapid (and sulfur-intensive) industrial activity" the temperature instead of continuing to fall actually rose slightly You are actually agreeing with my case
Lets make this simple, where's the correlation in the following?
Year | Sulfate Aerosols | Temperature change |
1900-1944 | Increased | Increased significantly |
1944-1950 | Increased | Decreased significantly |
1950-1960 | Increased | Increased slightly |
1960-1970 | Increased | Decreased |
1970-1980 | Increased | Steady cooler |
1981-2000 | Increased | Increased significantly |
2001-present | Increased | Steady warmer |
Let's go back and see what Dr. Tett said, exactly (I even underlined this part): "
Let's not, his "program" has already been debunked by me and others here
Where do you get the solar irradiance increase value?
See the charts posted by others above
Not quite wrong, inaccurate. I should have quantified. Your quote was qualitative and concerned the general compositon of the Asian aerosol. My statement was about emissions from India: "India's smoke does not have an appreciable sulfate component, for example." The Asian Brown Cloud (PDF) Excerpt:
"SO2 emissions (which are converted to sulfate aerosols) are 5 Tg/yr of sulfur for India, 28 Tg/yr for China and 25 Tg/yr for North America.
Again you are arguing my case for me against your argument that sulfate aerosols cooled the planet only between 1945-1980
unless you care to explain how 50 Mt/Tg per year of sulfate aerosols can cool the planet in 1970 yet even more in 2002 (56 Tg per year in just 3 regions - 70-80 tg total worldwide) of the same sulfate aerosols don't?
That graph tracks very, very closely up until mid-1975....
How has the drop in the earth’s magnetic fields (as the north magnetic pole began “streaking” away from the north Hudson Bay towards Siberia) correlate to that mid-70’s swing?
I don’t think post 241 said that there was a lag due to solar variability.
To buttress your case, you provide a link to a study by James Hansen and others. The study does not appear to consider the sun. If you don’t consider the sun, you won’t find a solar effect.
It's apparent that you have a need to think that it has been refuted. I will not try to dissuade you from needing to think in this manner. However, what I have placed there is standard scientific understanding of these topics. Refutation of standard scientific understanding is not accomplished by a couple of posts on a political discussion site -- no matter how smart the people posting may or may not be.
There clearly are parameters left out of the fool models that may EASILY serve to amplify the raw solar influence: for example, suppose that the additional solar activity translates to less cloud cover and lower albedo instead of ASSuming a constant albedo. That can EASILY account for the temperature rise of the last century.
You may be right. Demonstrate your supposition has the desired effect through the scientific process. Let other scientists examine your methods and evaluate your conclusions.
There certainly are time lags we know about, and there may easily be lag mechanisms we DONT yet know about that explain the temperature rise of the last 30 years and are a result of solar influence.
Scientist can only theorize based on what is known and observable. Anything beyond that is speculation.
In addition, the very recent NASA release of aerosol data suggests the apparent lag in temperature of the last 30 years may well simply be aerosols masking the additional solar irradiance, just as suggested by this graph years ago:
The same effect applies to being a counter-effect of GHG warming. And if correct, it is not good news regarding the eventual impact of GHG warming.
As far as that link, Ive seen that before and consider it a good site to get data (but not necessarily good interpretation), and the thing that stands out is that the cosmic measurements they show are ALL during a period of historically high solar activity, of course.
The current scientific understanding is that there has not been a significant increase in solar output since the 1950s. Apparently solar activity is high -- but it hasn't changed much since the 1950s. Proving that the Sun is the primary cause of currently observed warming must address that.
Of course youre not going to bother trying to refute the rest of that post:
I don't support Kyoto, so I don't care. I care about accurate presentation of scientifically-acquired knowledge.
And, I'm still wondering why you haven't come up with a 'splanation of how the IPCC published models have Earth's temperatures going down despite increased irradiance during the 20th century.
I'm not sure what you mean. The general pattern, and the models, have warming into the early 40s (with a solar component), cooling to the late 1970s, and warming since. Now, if you're thinking about the "blue bands" in the figure I posted from the IPCC SPM4, they show that pattern. According to The Role of the Sun in 20th Century Climate Change, there has not been an appreciable increase in solar irradiance in the latter half of the 20th Century (which I've said before). So the blue (natural forcing) bands shouldn't show a temperature increase due to natural forcings from the 1950s to present, because there hasn't been a natural forcing observed that would cause a temperature increase.
Ah well -- have fun with this...
I think not.
And good luck to Dr. Solanki and his collaborators.
For the information of others:
New Experiment to Investigate the Effect of Galactic Cosmic Rays on Clouds and Climate
"Spots! Spots!...."
Maybe there was a blip in the early '60s, but the 1970s stayed cool. After all, when were those "global cooling" stories written?
Surely you don't want to discuss long-term trends on timescales less than a decade.
Let's not, his "program" has already been debunked by me and others here
Feel free to think so.
unless you care to explain how 50 Mt/Tg per year of sulfate aerosols can cool the planet in 1970 yet even more in 2002 (56 Tg per year in just 3 regions - 70-80 tg total worldwide) of the same sulfate aerosols don't?
The current level of sulfate aerosols certainly does havea cooling effect. But now, the warming from GHGs has significantly increased, overriding the cooling contribution from the sulfate aerosols. That's how the climate scientists explain it. I just repeat what they're saying.
Quote: "The rapid warming that has taken place since 1970 is, according to the model, attributable to a heating effect from greenhouse gases and a cooling effect from sulphate aerosols. Fundamentally we showed that climate models cannot simulate the observations unless forcing factors additional to greenhouse gases are included."
Here is what it said: "Someone is forgetting some very basic thermodynamics. The heat source may have reached a constant temperature, but the Earth isn't necessarily at equilibrium with the new warmer environment yet. Comment by Awatson 21 Jul 2005. AaroninCarolina: "This echoes my earlier point about a time lag in response to solar irradience changes"..
To buttress your case, you provide a link to a study by James Hansen and others. The study does not appear to consider the sun. If you dont consider the sun, you wont find a solar effect.
An examination of climate forcings relevant to current observations, which is what the Hansen paper contains, considers that which is changing and how those changes will affect climate. While there may have been a slight increase in solar activity influencing temperature up to the 1950s, there has not been a climatically significant change since then. Since there is no observational evidence that changing solar activity is influencing current global temperature trends, there is no solar forcing change to examine.
Dang, I need to get on 6 meters for some DX. BTW, I’m an amateur radio operator.
This thread had legs. Some real good debate going on here. I have been spending some time reading the links and trying to get up to speed on the new data that has been gathered concerning the sun. From what I understand there are two factors to consider with respect to 'solar brightness'. Activity on the sun (sunspots) which causes solar output to vary up and down has an approximate 11 year cycle. We are currently at the end of the cycle and waiting for cycle 24 to begin. When there are very few sunspots during a cycle the Solar radiance is lower (Marauder Minimum). The Solar radiance during the last 5 cycles has been peaking at roughly the same elevated peak levels and also dropping to roughly the same elevated low levels. So other then the time exposure of these elevated levels (as compared to levels from the mid 1800's) you are making the claim that there is no other upward driving force to temperature. Well there is another Cycle with respect to sunspots that has a periodicity of 70 to 90 years and Lassen called it a Long Term Variation. Here is his description of the Variation.
A different solar parameter showing long-term changes is the length of the approximately 11-year sunspot cycle. This quantity is far from being constant. It is known to vary with solar activity so that high activity implies short solar cycles whereas long solar cycles are characteristic for low activity levels of the Sun. Gleissberg (1944) demonstrated that the variation occurred in a systematic manner with a periodicity of 70-90 years similar to, but not exactly in phase with the variation of the magnitude of the sunspot number.
That could be the other forcing factor. Yes, the peak Solar Radiance has been roughly the same for the past 5 Solar Cycles, but the frequency which those peaks are occurring at is greater. So more peaks means more peak Solar Radiance in a given time period.
I now have a 1X3, but I won't put it out on here. I'm not active anyway and it just gives people another way to look you up and hassel you, so I hold that back.
10 meters QRP was my favorite thing during the 11 year cycles in the past.
Nowadays, I just work my NEXTEL walkie talkie with Mrs. Waspman... Phhhhht!!! (well, they put a frankenpine up in our back yard almost!)
Enjoyed your comment, MarkL!!!(wide grin)
Great job of plumbing up the envirowhacko’s!!!
BTw, I have a couple of Radio Handbooks, the 1st edition from 1935 and the 14th or 15th editionsfrom 1957/59. I think in both, I know the latter, there is a claim that there could be a larger 22 year sunspot cycle too.
BTw, I have a couple of Radio Handbooks, the 1st edition from 1935 and the 14th or 15th editionsfrom 1957/59. I think in both, I know the latter, there is a claim that there could be a larger 22 year sunspot cycle too. About activity being the highest from the 1950’s onward, I do remember reading about TV Dxing back in the 1950’s where people in the Eastern US pulled in stations as far away as Cuba and Hawaii. In the late 1930’s, when the sun got active, some TV researchers in New York managed to watch BBC 405 line television in the 40 - 45 Mc band from across the Atlantic.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.