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.
If sunspot activity is markedly reduced over several solar cycles, that indicates the sun's output is lower. I.e., Maunder Minimum and Little Ice Age. They certainly know that. Any other effects don't have an experimental evidence as a forcing factor. Cloud cover - yes. It's the main uncertainty. I certainly hope it starts ramping up soon.
And to think all these ice core data and tree ring data really gives us an accurate picture of previous climates is just bazaar.
IN this marketplace, some data is more meaningful and interpretable than others. Ice core data is extremely reliable as a CO2 concentration indicator and quite reliable for temperatures (stable oxygen isotopes, particularly from polar ice). Tree rings are certainly more problematic as temperature proxies but still indicate climate variation related to both temperature and hydrologic conditions.
Though we are philosophically different on this issue, don't dismiss what scientists can learn just because you don't want them to learn something you don't want to know.
There are people who strongly disagree with that assessment. Here is one for instance.
Heard on Coast last night that the Little Ice Age following in short order the Black Death is related. Agriculture causes global warming and when 1/2 the population died agriculture also dropped way back, so the global warming effect dropped off and there it is—Little Ice Age. It was mentioned by an eminent atmospheric scientist several decades ago that we would be 5000 years into an ice age now—almost all conditions are right—except for global warming brought on by agriculture.
for starters.
No, they say that because we've allowed the situation develop, where through preferential funding and publishing for those climatological and meteorological researchers (to those willing to wave the AGW banner), we're getting the skewed results of that corruption of (what used to be) a large scientific field.
Corruption is extremely dangerous, insidious, and a hallmark of the Left, e.g. former Senator Tim Worth (D-CO) "What we've got to do in energy conservation is try to ride the global warming issue. Even if the theory of global warming is wrong, to have approached global warming as if it is real means energy conservation, so we will be doing the right thing anyway in terms of economic policy and environmental policy."
Talk about your basic, bastardized morals! They openly would have their ends "justify" whatever expedient means, in defiance of truth, as they may deem is required.
You can float anywhere on that little raft.
HF
Huh??? ROTFLMPO
Great environazi quotes, too, by the way.
If I make comparisons for my clients, as a bookkeeper, I better have the facts and figures to make such a presentation.
Where are the records for a 1,000 years ago for the sun?????
I sometimes cannot believe what people will accept for “statistics”.
For some idiotic reason deluded minds like cogitator don’t want to believe that when the sun has increased in output by 0.3% over the last 200 years or so that it is NO surprise that the earth has warmed by about 0.3% during that same period of time.
More and more evidence of the historical influence of the sun won’t sway them because, I guess, they believe the output of the sun is nearly constant.
I believe, though, that the sun has varied in the past by enough to account for all the climate change Earth has experienced... including the last century. The CO2 rise is quite likely the result, not the cause, of the temperature rise - at least ice core data suggests that strongly since it lags the temperature by about a millenium.
The 80s-90s temp rise is more than the sun’s but the sun took a sharp temp rise from 1900 or so until about 1950 and been relatively constant since then. There may simply be a lag of several decades in the Earth’s temperature in response to the Sun’s radiation.
The next two solar cycles have been predicted by scientists now, and it seems the coming one may be high temp, the next one (15+ years from now) may be the lowest of the last 100 years. After that, who knows, but I am one who is hoping that it stays on the warmer side of the last 100yrs rather than sliding back to the Middle Ages type of event, or an even lower level of activity. Ice Ages begin that way, and we certainly don’t want to see global temperature 8C colder.
To prove they're wrong or significantly inaccurate, you have to show why. Merely thinking they're wrong is insufficient, and the scientists already know where the main uncertainties are. Attribution cannot be done without models.
It is peculiar to me that you would seek to prove that Lindzen's conclusions are erroneous when he dissents from IPCC conventional wisdom by presenting the IPCC's own charts as proof against him.
I was addressing your statement here: "You know enough about Dr. Lindzen, I am quite sure, to know that he meant that some amount of warming as a result of increasing GHG's is undeniable, but not the main force behind the recent warming."
The IPCC chart shows, as a summary of current research and knowledge, that nothing else -- especially that which is classified as "natural" -- could be the main force behind the recent warming other than greenhouse gas radiative forcing.
So if Lindzen thinks as you think he does -- and I believe what you wrote is reasonably accurate -- I have strong confidence, at or above the 90% level, that he's basically wrong. And I've shown just one of many reasons why.
thanks.
warming up mars too, no doubt.
tracking btt
You’re right! I agree. Global warming or lack thereof is caused by the sun! (Book of Revelations Ver. 6.0) But we have the media morons, academic effetes, political demagogues, and assorted other lunatics who think it’s caused by too many styrofoam cups, or whatever floats their boat.
True.
Level of sunspot number is an indicator of the average irradiance of the sun, but you have to take an decade long average to mean anything, as you certainly know.
All sunspot cycles have times with no, or very few, sunspots, but the immediate solar irradiance doesn’t change with number of the sunspots. The sun would be cold right now if that were true. Even during the Maunder minimum, when there were very few sunspots seen for many decades at a time, the irradiance of the sun was definitely no lower than 99.5% of the present.
I’m beginning to see emerging in the scientific literature solar mechanisms which can account for changing solar irradiance cycles. In particular, there recently was published a proposed mechanism for the natural 100,000yr and 41,000yr cycles. There are defintely others in addition to the 11/22yr solar cycle, too.
At this time, I’m getting more and more convinced that cycles having to do with the sun and others (like earth’s ocean subsurface currents and the CO2 source/sink resulting from that, biological influences, etc.) are responsible for the bulk of the temperature changes on Earth, as well as most of the CO2 changes seen throughout history, including the most recent increase.
Take a look at the last 8 years’ data. What is the “trend” of the temperature?
In actuality, a .3% rise in 200 years IS fairly constant. However, nearly constant is not the same as constant, and .3% can be significant.
All in all, I know that there is nothing I, or anybody else can do to change what is going to happen. So I will continue to live my life as I see fit, not worried about my “carbon footprint” and maybe slather on some more sunscreen.
My point is that the skeptical argument "it hasn't warmed since 1998" is predicated on the high temperature of 1998, which GISS notes (the link I provided) was 0.2 C degrees above the trendline. The trend from 1990 to 2007 is nearly uniformly up. If 1998 wasn't there to skew everything, it would be dead obvious to anyone.
From Goddard Institute of Space Studies:
The point above 0.6 is for 2005.
Ping for reference.
Post 198 provides one answer.
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