No, the Antarctice ice sheet is NOT shrinking.

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Qev
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Post by Qev » Sun Apr 16, 2006 3:18 am

Living things can greatly affect the environment, and even the geology of planets, and humans are no different from any other living species in this regard. We sometimes forget that the world isn't some inert stage that we just act on.
Don't just stand there, get that other dog!

randall cameron
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Post by randall cameron » Sun Apr 16, 2006 10:56 am

But! how much is man compared to the earth cycles and sun cycles.
I do not think anyone knows. I have seen research indicating that a single major volcanic eruption dwarfs the annual man-made production of greenhouse gases, and there are many other factors at work, both natural and man-made, such as the effects of particulates and cloud cover that are really poorly understood.

Prudence dictates that we assess the costs and benefits of significantly reducing our output of greenhouse gases, and similarly look at the costs of adapting to global warming. Either way, we need to do some serious long-range planning to mitigate the consequences and manage the costs, because warming is clearly happening.

Even if the US signed onto Kyoto, it would only slow things down a bit. Several nations in Europe are nowhere near meeting their Kyoto targets (others are, however). And emerging large economies like China, India, Brazil, Mexico and Indonesia are right to argue that the OECD were allowed to emit greenhouse gases throughout the 19th and 20th centuries on the way to building their present economies, so why should emerging economies be prohibited from doing the same, when the cost disadvantage of being environmentally friendly might prevent them from catching up?

Of course, at the end of the day, carbon-based fuels are going to be exhausted sooner or later whether we curb our emissions or not. That means we need to invest in new technology for large scale solar power, make a breakthrough in fusion power, or we are going to find ourselves building more nuclear reactors and wondering where to put the waste.

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Qev
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Post by Qev » Mon Apr 17, 2006 5:55 pm

randall cameron wrote:I do not think anyone knows. I have seen research indicating that a single major volcanic eruption dwarfs the annual man-made production of greenhouse gases, and there are many other factors at work, both natural and man-made, such as the effects of particulates and cloud cover that are really poorly understood.
I've heard that before, as well, however bear in mind that 'major' volcanic eruptions are rare events, while human output of greenhouse gases is both continuous, and increasing. And that single volcanic eruption has significant effects on the planet's climate... so what is our constant input doing?
Prudence dictates that we assess the costs and benefits of significantly reducing our output of greenhouse gases, and similarly look at the costs of adapting to global warming. Either way, we need to do some serious long-range planning to mitigate the consequences and manage the costs, because warming is clearly happening.
Definitely! I doubt we'll ever turn the Earth into a twin of Venus (that's going a bit far), but that doesn't necessarily mean we're going to like how it does end up. :) And even if we aren't causing the warming, the consequences of it are not going to change any.
Even if the US signed onto Kyoto, it would only slow things down a bit. Several nations in Europe are nowhere near meeting their Kyoto targets (others are, however).
Even if they were meeting their Kyoto targets, it would only mean that they're slowing the rate that their greenhouse gas emissions are increasing, and not actually reducing the rate at which they're being emitted. Every little bit helps, though, I suppose...
Of course, at the end of the day, carbon-based fuels are going to be exhausted sooner or later whether we curb our emissions or not. That means we need to invest in new technology for large scale solar power, make a breakthrough in fusion power, or we are going to find ourselves building more nuclear reactors and wondering where to put the waste.
If we're smart, we'll put the waste right back into the reactor. :)
Don't just stand there, get that other dog!

Martin
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Post by Martin » Wed Apr 19, 2006 7:32 pm

Sunlight reaching Earth has been growing dimmer, which may seem surprising given all the international concern over global warming. At first glance, less sunlight might hardly seem to matter when our planet is stewing in greenhouse gases. But the discovery of global dimming has led several scientists to revise their models of the climate and how fast it's changing.

The good news is that pollution controls have slowed and possibly even halted global dimming during the last decade. The bad news—and the ironic twist is—is that without pollution, more sunlight is reaching Earth, revealing the full impact of global warming. Although all climate models have important uncertainties, the unsettling implication is that, with dimming fading away in many regions, global temperatures may rise even faster than most models have predicted.

Martin
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Post by Martin » Wed Apr 19, 2006 7:35 pm

Climate change skepticism, it seems to me, has a number of different sources. Firstly, there are what one might call arguments from common sense. It seems obvious that if meteorologists have trouble forecasting the weather three weeks from now, how on Earth can they claim to predict it three decades hence?

The answer to this, of course, is that scientists are forecasting not weather but average weather (i.e., climate). It is much easier to predict averages than individual values. The casino owners have no more knowledge than the gambler where the ball will fall on any particular turn of the wheel. But the owners know the averages are in their favor and can predict with mathematical precision the monthly take from each roulette table.

In fact, only three factors determine the planet's energy balance: the sun's output, the Earth's reflectivity, or albedo, and the thermal properties of the atmosphere, which are affected by the level of certain trace gases like carbon dioxide and water vapor. Reduced to its essentials, the greenhouse effect is a problem in 19th-century classical physics, and the basic theory was worked out with pencil and paper in the 1890s. To say that increasing CO2 levels leads to more heat trapped in the atmosphere is really no more scientifically controversial than saying you'll feel warmer if you put on a sweater.

The difficulty arises when you try to work out what this extra heat energy will do. Will it lead to increased rainfall, or more cloud, or higher winds? It will raise temperatures, but by how much? This is where the complex computer models and the (legitimate) scientific arguments come in—accompanied by the occasional science filmmaker!

What's required is another industrial revolution. America is rather good at these. Britain led the first (coal and steam), but America has pioneered the rest (the internal combustion engine, telecommunications, computers). Each one only adds to our prosperity, and it will be the same once again.

But there is an important difference from previous industrial revolutions. This one requires political leadership; the market on its own won't do it. To combat global warming, the world desperately needs U.S. leadership.

I am optimistic enough to believe that we won't have to wait much longer. The pace of global warming is now quickening to the point where it will soon be obvious to everyone. When you can discuss the question sitting at a pavement café in London in November in your short sleeves shirt, you just know something is up, and all skepticism becomes moot. Global warming is nothing less than a fact, and it has to be faced.

harry
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Post by harry » Thu Apr 20, 2006 7:54 am

hello all

Global warming

Is man's actiion the last straw that breaks the camels back.

The question that come to mind is with global warming do other living things get an advantage.

Increase C02 increases plant and sea life production and therfore may increase oxygen.

Increase temp should increase the rain cycle less dry areas

I could be wrong.
Harry : Smile and live another day.

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