geez....shhhh!....Don't the people at NASA really know that there is no "real" link between solar activity and the climate? What is the "real" message here?

The link obviously is more clearly due to all of the CO2 produced by the ancient peoples in burning fossil fuels. Oh, wait, that doesn't explain it, they were "in tune" with their environment unlike modern Americans.

Are they certain that there were no SUVs back then? Or activists traveling the globe concerned over auroras and water levels?

Interesting info though. Amazing the correlations that can be derived from two, seemingly disparate, pieces of data.

What?? You must be joking. A link between sun and climate? No way!! Everyone knows that only carbon dioxide, specifically that produced by humans, is the only mechanism that could possibly cause climate change. What are you trying to pull here, anyway?

And what's this about solar activity having some connection with the NAO? That can't be, either.

/sarc off

Seriously, wouldn't you expect solar activity to be linked to climate change? Duh!! It's either that or someone is burning fossil fuel on Mars, Jupiter, Titan, and Pluto. They seem to be having some climate change going on, also.

Very fascinating! I would sure like to read about the findings NASA found and how it relates to past climatic changes. Is there any more information or a link where one can find more about this? Or is this something that will be hidden away from the public?

I want to know what Jim Hansen has to say about this ! You remember him, that top NASA Godard official who said the Bush administration tried to silence his public statements regarding AGW, the same guy who told Tom Brokaw "the science is overwhelming !" I know......... the Bush administration must have coerced these NASA JPL guys into publishing this rubbish !

If I may quote Nelson (simpsons) "HAW-HAW"

Maybe they will relax this AGW crud once the elections are over. I hope..................

Kudos to you Laura for posting this!

Michael J.

(I was the Michael who has been posting in other threads, however, it looks like we have another so I will post as Michael J. from now on to avoid confusion.)

Laura,
That is the 1st time I read that the NAO exteneded its reach so far. I know some anthropologists (Dr Brian Fagan of UC comes to mind) have blamed several ancient Egyptian famines
on EL Nino. How these different teleconnections relate to eachother is a fairly new science. I think intuitively the Sun ties everything together; however, I would believe that the Pacific -due to its sheet size- holds the key. How well it can manage heat transfers and heat absorbtion is key to not only El Nino, but to the HCL (Thermohaline Circulation), and indirectly the NAO. Cloud cover, as least as it provides a negative temperature feedback, we are discovering may be in some way tied to longterm irradiance of the Sun.

There are still so many newer parameters, forcings, and feedbacks, that it could literally be decades before we discover The Rosetta Stone of our climate.

Is that a negative NAO or a positive NAO relative to the Indian Ocean when the solar activity is high? I'm confused.

At last an intelligent discussion about climate. This is the way to educate people, not fear mongering.

Hope springs eternal among the global warming delusionists! Did they even read the linked article? If so, they don't seem to have understood it.

To summarize: This particular study has no implications at all in terms of any significant net global effect on temperature. The fact that there may have been more (or less) precipitation in a certain region says nothing about how warm it was in that region and, given that it's the NAO we're talking about, any precipitation change in the area of the sources of the Nile would likely have been balanced by a countervailing change elsewhere.

While past variations in solar output have in the past certainly affected global temperature, they cannot be responsible for the present warming trend since a) direct solar measurements over the last fifty years show no significant irradiance changes and b) the pattern of atmospheric warming from increased greenhouse gases (a warming troposphere and cooling strosphere, which has been observed) is different from the even warming that would be expected with increased irradiance.

(Note to Michael: Yes, it's "hidden away" in plain view. The journal in question is subscription-only, but you can pay to download the individual article if you like, or look at it for free if you have a suitable university library anywhere close at hand.)

Steve Bloom,

50 years, eh? That's one heck of trend you have there. Tons of data in that 50 years. I see your back to drawing your line and then plotting your data. This new info doesn't fit your preconceived ideas; therefore, you throw it out.

I'm not sure where you get your info, but since you apparently have a limited source; I shall provide you with some links, so that you may educate yourself.

The study linked below addresses decadal long cycles in solar flux with the maxima coinciding with higher temperatures. Although the change in solar flux is only 0.1%, it's enough for them to discern a pattern over the last 50 years.

Coughlin, K. and Tung, K.K. 2004. Eleven-year solar cycle signal throughout the lower atmosphere. Journal of Geophysical Research 109: 10.1029/2004JD004873

On a centennial scale, the following authors state (in their own words) "the weight of evidence suggests that solar changes have contributed to small climate oscillations occurring on time scales of a few centuries, similar in type to the fluctuations classically described for the last millennium: the so-called Medieval Warm Period (900-1400 A.D.) followed on by the Little Ice Age (1500-1800 A.D.)." It's also interesting to note that the sun could also be responsible for the latest warming where the temperatures haven't even reached the maximum temperatures achieved during the Medieval Warm Period when carbon dioxide concentrations were 100 ppm less than today. How does that happen, Steve?

Bard, E. and Frank, M. 2006. Climate change and solar variability: What's new under the sun? Earth and Planetary Science Letters 248: 1-14.

These are only two of dozens of papers on the subject. However, if you limit your sources of information, I can see where you might miss these types of papers.

There are/were not DIRECT measurements of solar irradiation over the past 50 years, since orbiting satellites have only been around since the late 1970's, and the first satellites sent up to explicitly monitor the sun have only been there a few years. Measurements from ground based instruments, especially those in use 50 years ago, with the atmospheric interference, can not be considered reliable.

Remember, the eruption of Mt.Pinatubo is estimated to have blocked only 1%-2% on incoming solar radiation, yet it was sufficient to drop global temperatures by 1-2 Deg F. It is also interesting to note, according to the Global Volcanism Program operated by the Smithsonian, that since Pinatubo there have been no significant eruptions to recharge the stratospheric volcanic aerosol load, and at no time since monitoring began has the aerosol loading been so low. Now the scientist I spoke to would not comment regarding the effect on GW other than to say that more solar radiation is reaching the surface of the earth than just a decade ago. HMMMMM....... 1%-2% is not a very big number.

Also interesting to note is that solar scientists have been reporting unusually high solar activity given that we have just passed the solar minimum in the 11 year cycle. Only a month ago a new huge eruption was reported on the sun's South Pole, which they said is even a bit unusual during the solar maximum. Solar scientists are predicting activity during the upcoming solar maximum to be anything from near normal to extremely high; the focus, of course, is the potential impact (danger to) on electric power grids and orbiting satellites, not GW. However, the point is that only small changes are needed to affect the system - after all we are talking about an increase of only 150ppm (approximate - relative to the starting reference) of CO2. And before anyone says that represents a doubling of CO2, doubling a small number is still a small number.

The point is that other factors should not be so readily dismissed, and although the climatologists seem to do so, I have not heard any of the solar scientists or volcanologists come forward to say that these factors can absolutely be ruled out.

To Steve
Hope does, in fact, spring eternal with those of us who have not bought into the fear mongering of politically-driven speculation. The gloom that you are looking for would have to subordinate the role that the sun plays in our climate to that of controllable CO2 emissions. Hope you enjoy the gloom, while I'll opt to cast my lot with weather cycles. Has it been only 30 years since we were warned about global cooling?

Except there is some fairly clear paleoclimate data brought out recently that points to atmospheric carbon being a following indicator, not a cause of global warming (shhhhh, don't tell anyone about the small fraction of GHG CO2 is, H2O is far and away the dominant GHG). Ooops, don't forget that cleanup of air pollution over the last few decades has to a large part removed the aerosol pollutants, which increase cloud cover (that pesky H2O GHG again) and contribute to cooling. Less cloud cover, less reflection of solar energy and the climate gets warmer. WOW! What a concept.

Oh well, just don't accept any data that predates TWC and you will be alright.....

Paul, I fear you may be chasing a false dichotomy.

The measured influence of solar variations is one of the complicating factors in understanding changes in the atmosphere, including AGW. The question is not whether or not such solar variations occur. The question, instead, concerns the relative magnitude of their contribution -- especially in the context of the greenhouse effect forcing that results from the skyrocketing atmospheric CO2 emissions.

I think one takeaway is that whatever effect solar variability may have, that effect is additive to the measured and predicted effects of increased CO2 emissions.

Kamatu:

Thanks for bringing up a very good point that reduced pollution has cut down on clouds thereby allowing more sun energy to reach the earth. I forgot all about that concept. Wonder what the reply will be since I would be willing to bet my last dollar that the AGW proponents of today, at least those old enough, were the same people in the 70's protesting about how we, mostly America I would guess by the way, were killing the planet by polluting. Kinda ironic isn't it.