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WARMING UP
JANUARY 4, 1996
TRANSCRIPT
British meteorologists report that the Earth's surface was higher than the average in 1995. Scientists have long debated the warming phenomenon and what causes it. Paul Hoffman, the editor-in-chief of "Discover Magazine" explains.
PAUL HOFFMAN, Discover Magazine: (New York) The British Meteorological Office has been measuring the average temperature of the Earth from the 1850's, and what they've found is that 1995, despite the cold we've just had the last month, was the warmest year on record. It was warmer than 1990, which was the last previous record, and that the last five years are the warmest five-year period that we've ever had during these measurements. And that's interesting, because in 1991, we had the Mount Pinatubo, which is a volcano that went off, and--
CHARLAYNE HUNTER-GAULT: In the Philippines.
PAUL HOFFMAN: Right. And it had a cooling effect. All the particles that it spewed out reflected sunlight away from the Earth, so even with the cooling, which scientists estimate was about 2 degrees, you still had global warming taking place.
CHARLAYNE HUNTER-GAULT: But how much warming is it? I mean, only .07 of a degree higher, is that much?
PAUL HOFFMAN: .07 of a degree higher, but you have to take into effect the fact that Mount Pinatubo lowered the temperatures, and the thing that's happening you've seen a one-degree rise in the temperature just in this century. If you look back to when we had the last Ice Age, the last Ice Age ended about 10,000 years ago, and the average temperatures of the Earth were only between somewhere between 5 and 7 degrees cooler than they are now, yet, we had ice everywhere. I mean, Long Island was created when glaciers melted and dropped it off, so it doesn't take very much of a change in temperature to really have widespread effects on the Earth's climate.
CHARLAYNE HUNTER-GAULT: Like what? What kinds of effects?
PAUL HOFFMAN: Well, what you're going to see and you're seeing right now is parts of the Antarctic ice shelf are breaking off. We had a 1000 square mile piece that broke off this year. You have ice slowly melting, sea levels rising. You have places like the Maldive Islands that's only a meter above sea level that could be completely underwater. I mean, here where I am in New York, if global warming actually takes place in the 21st century according to some models, you'll have a lot of Manhattan that's underwater. You have growing patterns changing around the world. It's not all bad effects either. You may have parts of the world where it's hard to grow crops now because the growing season isn't long enough where you'll actually be able to do that. You'll have the monsoon cycle in Southeast Asia affected and maybe you would have drought there. I mean, it doesn't take very much to change the climate. The big debate is, is mankind influencing global warming, or is it just a natural cycle?
CHARLAYNE HUNTER-GAULT: And mankind, by mankind, you mean certain kinds of emissions and things like that?
PAUL HOFFMAN: Absolutely.
CHARLAYNE HUNTER-GAULT: Explain that.
PAUL HOFFMAN: Yes. What the greenhouse effect is all about is carbon dioxide that's building up in the atmosphere when we burn coal, when we build--burn wood, and what happens is that carbon dioxide traps sunlight, and it's called the greenhouse effect because it's just the way greenhouse glass, you know, traps sunlight in, in a greenhouse. Okay. The question, though, is the sun also fluctuates just a little bit in intensity, and we have volcanoes that go off, and even though global warming is taking place, is it really due to these manmade emissions, or is it due to a natural cycle of the Sun?
CHARLAYNE HUNTER-GAULT: Right.
PAUL HOFFMAN: And slowly, the consensus of scientists is that there's a manmade element to this. And if you turn back the clock to 1988, you had only one scientist, a guy named Jim Hanson here at the Goddard Space Institute, saying that global warming was due primarily to human beings, and now you have the UN that just a few months ago a panel of scientists said that there's definitely a human element, so you see the consensus slowly coming around to the human contribution.
CHARLAYNE HUNTER-GAULT: So this study today, how does it affect the debate, because there are still those who are very skeptical, if not downright dismissive, of the very idea of global warming, let alone of human, the human element here?
PAUL HOFFMAN: Well, I mean, you're right, Charlayne. I mean, this does not prove that global warming is taking place. I mean, it's like going to a casino and you throw a few sixes in a row, you don't know that the dice is rigged. But this is one more little piece of evidence that global warming is taking place.
CHARLAYNE HUNTER-GAULT: How do you think this is likely--I mean, you say that the debate is going on and it's certainly been lively in the literature that I've read--how do you think this is going to affect policy action on this? Because those who are in the camp that say this is very much the effect of human beings want governments to take action. Those who say that this is natural causes and nothing substantial has really happened in the temperature over the years say nothing should happen. How--
PAUL HOFFMAN: Well, it's certainly ammunition for those that would like more government regulation of industry. The difficult thing--
CHARLAYNE HUNTER-GAULT: To keep them from burning coals and--
PAUL HOFFMAN: Exactly. To move away from fossil fuels to other forms of energy. The difficulty is it's very hard to roll back the clock. I mean, even environmentalists who think we should stop the burning of fossil fuels, it's going to be very difficult. I mean, we have countries like China, where the population is exploding, that would like to achieve a greater standard of living. They're going to burn fossil fuels. Is it unfair of us in the West who have already achieved a certain standard of living to say to them, hey, you can't do that? I mean, these are problems that even if we agreed we wanted to roll back global warming would not be easy to solve.
CHARLAYNE HUNTER-GAULT: Well, what about the people in areas like Upstate New York, where you are--you are in New York, but Upstate and the Midwest, who've been submerged under mountains of snow for the last few weeks, does this matter to them? I mean, or should it?
PAUL HOFFMAN: Well, again, you know, what happens on a given day in terms of the temperature doesn't really relate to global warming. It's like my casino analogy. I could get six sixes in a row and it doesn't mean the dice is rigged. That's going to happen sometime. We're still going to have cold spells. We're still going to have warm spells. But what it means is on average the temperature is going to go up, and it will change growing patterns in New York and certainly in coastal areas in New York and in Long Island if the people that say global warming is taking place and if, indeed, the temperatures rise a few more degrees in the 21st century, you will see coastal areas that are underwater.
CHARLAYNE HUNTER-GAULT: All right. Big "if's." We'll continue to follow this. Thank you, Paul Hoffman, for being with us.
PAUL HOFFMAN: Thank you, Charlayne.
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