Wednesday, January 25, 2006

What we don't know about climate change 

Well, here's a baffling headline: "Baffled Scientists Say Less Sunlight Reaching Earth". The article is even more confusing:
After dropping for about 15 years, the amount of sunlight Earth reflects back into space, called albedo, has increased since 2000, a new study concludes.

That means less energy is reaching the surface. Yet global temperatures have not cooled during the period.

Increasing cloud cover seems to be the reason, but there must also be some other change in the clouds that's not yet understood.

"The data also reveal that from 2000 to now the clouds have changed so that the Earth may continue warming, even with declining sunlight," said study leader Philip R. Goode of the New Jersey Institute of Technology. "These large and peculiar variabilities of the clouds, coupled with a resulting increasing albedo, presents a fundamental, unmet challenge for all scientists who wish to understand and predict the Earth's climate."

If we don't understand the relationship between the amount of sunlight reaching the earth, cloud cover, and temperature, how is it that we know that an increase or decrease in carbon dioxide is responsible for changes in temperature?

Now, I appalled many of my conservative readers by suggesting a few weeks back that the precautionary principle should motivate us to prepare for global climate change. I accept the idea that the climate may be changing rapidly and in ways that are incompatible with the established patterns of human settlement and agriculture. We don't have to agree on why climate is changing to contend with the change. I therefore believe that we should invest heavily in crops that can thrive in climates that are hotter, colder, wetter or drier than those that prevail today. We need plans to resettle human populations that live in low-lying areas, such as on atolls and certain coastlines, in case the sea levels rise. We need to learn how to generate prodigious amounts of energy at reasonable cost, in case we need to spend a lot more money heating Europe or cooling Texas, Mexico or Vietnam.

But, however prudent it may be to plan for the consequences of climate change, I do not understand how it makes sense to try to avert climate change when we do not (apparently) understand the basic relationship between sunlight, cloud cover and temperature. How do we know that steps we take won't make it worse?


By Blogger Cassandra, at Wed Jan 25, 08:44:00 PM:

How do we know that steps we take won't make it worse?

That's what I keep wondering.  

By Blogger Lanky_Bastard, at Wed Jan 25, 09:07:00 PM:

Try this on for size. You get less sunlight inside a greenhouse than you do outdoors. The glass reflects a lot of wavelengths of light back out. It just feels warmer because the heat is contained. It's also why UV-activated sunglasses don't work in cars...but they still get plenty hot.

Of course increases in albedo may be more complicated. Science is often like that. At a minimum, the light reflected off the moon is a bizzare proxy for the measurement of Earth's atmospheric temperature.

The ancients didn't need to understand the subleties of microorganisms to know they should stay away from swamps to avoid malaria. We have enough knowledge to assert that increased greenhouse gases (ie CO2) will raise the Earth's temperature.  

By Blogger viking kaj, at Thu Jan 26, 03:41:00 AM:

Short term fluctuations of this type in both the earth's orbit, solar power, cloud cover, etc. are still only dimly understood. And the fact that we have such large populations living in low lying areas is a sign that our species right now is probably a little too successful for its own good. Nature tends to correct such imbalances lest we forget.

That said, the biggest long term challenge for the human species in my book is global cooling. 15,000 years ago a sheet of ice stood a mile and a half high directly over the spot where I am writing this. Any incredulous readers can take a walk in Central Park tomorrow to look at the evidence, it takes a lot of pressure to cut granite like that. The ancestors of the modern Europeans who insist we sign Kyoto were all living back then in a limited refuge in southern Spain (Iberia?), since the rest of their continent was basically uninhabitable north of the Alps. The only Wisconsin glacier any of us should want to see anytime soon is in the performance of their point guards. Until some climatologist can provide a definitive explanation, much less a creditable theory, of why we have ice ages then I just think all this global warming hooey is an effort to get more funding out of NOAA by some misguided neo-ludites who would should know better.

The one thing all the creditable climatologists seem to agree on is that we are in a presently in period of integlacial warming and that if the past is any indicator the next ice age should begin in another 10,000 years or so. I'm holding on to my Sorrels and down parkas for the time being, thank you very much.  

By Blogger Charlottesvillain, at Thu Jan 26, 09:13:00 AM:

It just keeps getting better and better. If legitimate, this kicks the last leg out from under Kyoto. Every assumption about the causes of climate change has been discredited, or at least called into sufficient question as to rule out drastic changes in practice.

Of course there has been plenty of research over the past 15 years indicating serious questions about these assumptions, but it has been muzzled by the political factions.

So it sounds like we're back pretty much to square one. I guess it doesn't really matter as long as climate change is meted out in a gender neutral manner.  

By Blogger Lanky_Bastard, at Thu Jan 26, 12:51:00 PM:

Hold on people! You have a conservative blogger's dissection of a journalist's interpretation of a scientist's research. I'm afraid if I let this go to the 10th comment you'll have proven Gallileo was wrong and the Sun revolves around the Earth.

Here is a quote from the scientist himself.

"No doubt greenhouse gases are increasing," Goode said in a telephone interview. "No doubt that will cause a warming. The question is, 'Are there other things going on?'"

No doubt.  

By Anonymous Anonymous, at Thu Jan 26, 05:11:00 PM:

"...other things going on..."

A pretty neutral description of an extremely complex system of interactions.

1) We depend on the "greenhouse" effect to maintain this planet as a livable place. With no "global" warming caused by the atmosphere holding in heat, the planet would be much colder than it is, and pretty inhospitable. What is the "correct" amount of global warming? As Mr. Viking Kaj implies above, we have had "global warming" for most of the last 10K years, and that's not been ALL BAD!
2) The oceans are a tremendous sink for carbon dioxide. While there are literally millions of tons of CO2 in the atmosphere, this represents only a fraction of what is dissolved in the ocean. If ocean mean temperatures rises just a few degrees or salinity changes, great amounts of CO2, dwarfing human year-in-year-out production, would enter the atmosphere. What could cause that, hmmmm?
3)Although there are many good and very intelligent scientists doing good research and writing papers on "global warming" and the causes thereof, we truly don't understand all the variables in this system. Computer modeling has advanced tremendously in the last 15-20 or so years, but computer modeling, while requiring a tremendous amount of time and intellectual ability, is not "fundamental" research, and should not be confused as such. Hence many, frankly irresponsible, things have been said and published on global warming, based on "computer modeling". This is not science in the sense that it is the search for new knowledge, but an application of science to form, basically, conclusions without strong foundations. Intellectually demanding, but not necessarily correct (fake but accurate?, naaahhhh).
4) Be cautious about any claims that "irrefutably" prove that runaway 'global warming' is/is not taking place. No one really knows, and it is by no means "settled" science  

By Blogger KJ, at Thu Jan 26, 05:19:00 PM:

When climatologists can tell if it will rain on my way home, I'll start listening to their "computer modeling" about the world wide weather in 2050.  

By Blogger Lanky_Bastard, at Thu Jan 26, 11:22:00 PM:

I give up. No doubt the Earth will stop warming in the face of such united denial.  

By Blogger geoffrobinson, at Fri Jan 27, 10:14:00 AM:

The Sun's output varies.

I'm open to greenhouse gases being the cause. I'm even more inclined to believe that the Sun has been more active lately. Or a combination of the two.

I want to see the Sun's output vs. temps.  

By Anonymous Anonymous, at Fri Jan 27, 10:14:00 AM:

my only point is that no one "knows". I am not persuaded either way as to whether "runaway" global warming is or is not taking place.
We don't know enought about solar output to tell if it is cyclical on a large time frame (tens or hundreds of years). We DO know that there is an eleven year cycle of maxima to minima on sunspot activity. What does that mean with respect to weather? How does the solar wind affect our planet's weather, if at all?
When I was in college, oh so many years ago, the theme then was global cooling and ozone depletion caused by flourocarbons in the atmosphere. Those concerns have somewhat faded: the global cooling has passed out of fashion, and changes in freon types and production seem to be having some effect on ozone depletion.
We may really have a serious problem with man-made global warming, or there may be a serious problem with global warming (non-anthropomorphic) that can only be ameliorated by a high-tech, industry-intensive effort by men to remedy it and save us all from being par-broiled_.
I am only put off by the superstitious twaddle of people who ascribe various attributes to "Gaia" or some such "Earth Mother".  

By Blogger Charlottesvillain, at Fri Jan 27, 03:14:00 PM:

Lanky, based on current research, I'd give argument as good a chance of stopping it as any of the other measures that have been suggested.  

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