Nasa study on Global Warming

[thegathering]

This is the study we've been waiting for for quite a while now.

http://www.nasa.gov/centers/goddard/...ld_warmth.html

One of the points states that:

Originally Posted by www.nasa.gov

The most important result found by these researchers is that the warming in recent decades has brought global temperature to a level within about one degree Celsius (1.8°F) of the maximum temperature of the past million years. According to Hansen, "That means that further global warming of 1 degree Celsius defines a critical level. If warming is kept less than that, effects of global warming may be relatively manageable. During the warmest interglacial periods the Earth was reasonably similar to today. But if further global warming reaches 2 or 3 degrees Celsius, we will likely see changes that make Earth a different planet than the one we know. The last time it was that warm was in the middle Pliocene, about three million years ago, when sea level was estimated to have been about 25 meters (80 feet) higher than today."

[KenWittlief]

it really bothers me that the history of the temperature of the earth is based on several assumptions and many second order effects

but they are talking in terms of one or two degrees, as if the earth has been instrumented with precision equipment for the last 10 million years.

[petek]

Originally Posted by KenWittlief

it really bothers me that the history of the temperature of the earth is based on several assumptions and many second order effects

True, but they're mainly based upon a well-tested, peer-reviewed and correllated proxy for temperature: the deuterium/oxygen isotopic ratio. First demonstrated by Willi Dansgaard in 1964, measurements of these trace gases trapped in ice core bubbles give a fairly accurate record of the temperature and atmospheric moisture content in the past. It may not be a direct measurement, but if it's good enough to be published in Science, Nature and a host of others, I figure it's good enough for me!

[KenWittlief]

well, yeah - but doesnt that tell you the temp of the area where the core sample was taken from? The earth is huge, almost beyond the ability of a human mind to comprehend.

I just find it hard to believe you can extrapolate the average temperature of the entire earth from ice core samples taken from several locations, over a period of millions of years

esp when our state of the art weathermen cannot tell me what the weather is going to be next week? Im not convinced we understand the climate of the earth as well as we think we do.

[Al Skierkiewicz]

Ken,
It didn't take much imagination to see the incredible melting of the glaciers in Alaska and Canada's Rocky Mountain ranges to know something is up. At several of the glaciers I visited, the retreat was measured in miles since just the 1950's. Even in the US, there are almost no glaciers left in Glacier National Park. In Barrow, the polar ice cap retreats more that 18 miles off shore during the summer, taking with it the local seal population on which the native people have depended for millenia. There is no doubt that warming is here, it's cause is what is in doubt. Considering the severe spike in temperature since 1900, it is hard not to imagine man has had something to do with it. Eighty foot rise in ocean levels means good bye to New York, Boston, L.A., most of Florida, Long Island, and most of the D.C. area as well. Pick your spot and it will likely be under water soon. I can only guess at the Pearl Harbor/Honolulu devastation but think of Island nations of the Pacific, Tahiti, Fiji, Guam, the Phillipines, the Solomons. Even Iwo Jima has more than 90% of the island only a few feet above sea level.

[KenWittlief]

back in the 1930's the mid west was hit with abnormal weather, that turned millions of square miles of farmland into a giant 'dust bowl'. People thought the midwest would end up being a desert. It didnt.

Back in the 1970s satellites showed the ozone layer covering the earth was collasping over antartica. Scientist said that within 50 years we would not be able to go outside without protective clothing, and that thousands of species would become extinct. Then the ozone layer recovered by itself, and they realized it was a natural cycle.

If we go back and look at what scientist have predicted in the past, we laugh at them now, so why the disconnect? Why do we laugh at them for getting it so wrong, but take ourselves so seriously?

[Al Skierkiewicz]

Originally Posted by KenWittlief

back in the 1930's the mid west was hit with abnormal weather, that turned millions of square miles of farmland into a giant 'dust bowl'. People thought the midwest would end up being a desert. It didnt.

Ken,
As I remember it, this was as much a fundamental error on the farming methods used as on the actual conditions of the time. The loss of natural grasses on the Great Plains led to widespread wind erosion.

Originally Posted by KenWittlief

Back in the 1970s satellites showed the ozone layer covering the earth was collasping over antartica. Scientist said that within 50 years we would not be able to go outside without protective clothing, and that thousands of species would become extinct. Then the ozone layer recovered by itself, and they realized it was a natural cycle.

I believe this hole continues to grow, but it's rate has been slowed now that certain flurocarbons have come into use in vehicle and home cooling systems. It certainly is difficult to predict long term effects with short term data.

Originally Posted by KenWittlief

If we go back and look at what scientist have predicted in the past, we laugh at them now, so why the disconnect? Why do we laugh at them for getting it so wrong, but take ourselves so seriously?

As in many things, the truth lies somewhere between what we are told and what we have believed in the past. I would rather be overly right in this case and compensate for the effect of man on the rising temperature then to do nothing. Falling back on Boy Scout lore (sorry but it does influence me) one should leave a place in better shape then it was when we first visited. "Take only pictures, leave only memories." And know that even boot prints can effect the local environment under certain conditions.

[Adam Y.]

It's a really complicated situation. Too many variables to deal with that I don't think anyone knows what is going to happen.

[KenWittlief]

Originally Posted by Al Skierkiewicz

Ken,
...As in many things, the truth lies somewhere between what we are told and what we have believed in the past. I would rather be overly right in this case and compensate for the effect of man on the rising temperature then to do nothing. ....

tbe reports I have seen about this being the worst thing in a million years say its already too late to stop it.

the temp is going to rise, the ocean is going to rise and there is nothing anyone can do at this point to stop it

if people believe these predictions then what effect is this going to have on peoples lives? will the price of property plummet in florida and other costal areas? Will Great Britain become like iceland when the gulf stream stops bringing warm weather that far north?

These predictions could have enormous financial impact on the lives of millions of people, and it doesnt matter whether they are correct or not. If people believe they are correct that is all it will take.

And we already have the state of california suing several automobile manufacturers for hundreds of millions of dollar for causing global warming. This is only the start.

[thegathering]

And we already have the state of california suing several automobile manufacturers for hundreds of millions of dollar for causing global warming. This is only the start.

Just imagine how many more lawsuits like this would follow. People are already starting to point fingers now instead of trying to stop it. California is pointing fingers at automakers instead of at the people that drive cars and their own government not providing enough public transportation.

If more doomsday reports come out, we can all expect that nothing will get done from the blame being passed around.

We almost need Captain Planet here to educate people how to save energy and reduce the amount of impact humanity is having on the environment.

[Al Skierkiewicz]

Originally Posted by KenWittlief

if people believe these predictions then what effect is this going to have on peoples lives? will the price of property plummet in florida and other costal areas? Will Great Britain become like iceland when the gulf stream stops bringing warm weather that far north?

Ken,
I can only tell you that I am happy to be sitting at 535 ft. above Sea Level.

[petek]

Originally Posted by KenWittlief

well, yeah - but doesnt that tell you the temp of the area where the core sample was taken from?

Yes - at the time that point in the core was the surface of the area in question. These gas bubbles are snapshots of the atmosphere at the time they became entrapped by snowfall.

Originally Posted by KenWittlief

I just find it hard to believe you can extrapolate the average temperature of the entire earth from ice core samples taken from several locations, over a period of millions of years

Ain't science wonderful? The mind-boggling intuition, effort and discoveries of scientists have amazed me just about every day since I was a kid.

Originally Posted by KenWittlief

esp when our state of the art weathermen cannot tell me what the weather is going to be next week?

The point is, we are discussing climate, not weather. Weather is short-term, chaotic and still largely beyond our ability to model. Climate is, in effect, the integral of weather - it is the long term averaged effect of weather, the activities of the sun, plants, animals and everything. It can be modeled with some degree of accuracy and testability.