Isramart : Carbon expert reminds us that global change is happening now

Isramart news:
This number shows Earth’s collective 3 trillion-plus metric tons of combined greenhouse gases in the atmosphere.
You’ll notice that it is a BIG number. And it’s already outdated. This picture was captured yesterday. Look at the counter today on the web, and the number will be bigger.

The volume of greenhouse gases is constantly ticking upward. Much faster than a watch. Steady as an oil derrick. As ominously as a time bomb.

“It keeps on going up while we’re talking and discussing possible policy; it keeps going up,” says Ronald Prinn, co-director of the MIT Joint Program on the Science and Policy of Global Change, the group behind this carbon counter and one of two major entities that measure global greenhouse gases in the atmosphere.

“Things are happening. We’re burning fossil fuels. We’re producing greenhouse gases and adding to the stockpile in the atmosphere,”

In New York City, this carbon counter looms large in Manhattan, thanks to a near-70-foot billboard topped by the moving meter that was launched by Deutsche Bank’s Asset Management Division to raise awareness about climate change. The billboard, just outside Penn Station and Madison Square Garden, was erected this summer, and stands as a reminder to all who pass by, such as those attending the United Nations Climate Summit this week.

The summit, a prequel to the Copenhagen Conference in December, brought together US President Barack Obama and China’s President Hu Jintao, who both explained some measures their countries would take to curb climate change. It offered jolting pronouncements, like the one from the Intergovernmental Panel on Climate Change (IPCC) that scientists’ models leave “no space” for inaction.

We talked with Dr. Prinn, a professor of Atmospheric Science who directs the MIT Center for Global Change Science, about those latest projections and the basic science behind them.

First, he explained, the carbon counter in NYC presents an aggregate of the 40 greenhouse gases, the largest one, far and way, being carbon dioxide in the atmosphere worldwide.

What does this number really mean? The atmosphere is so big, it seems like it could handle a certain amount of carbon.

Indeed, nature has ways to process or absorb carbon, replies Prinn. But there are limits and we’re testing them. Since the industrial age began (say 1750), the world has been adding carbon to the air from the burning of fossil fuels – coal, oil, gasoline — faster than natural elements can absorb it. The Earth’s forests and oceans, which serve as carbon “sinks,” are being tapped out. And we’ve been aggravating the situation by chopping down the forests that can capture and hold carbon.

So the carbon cycle is out of whack, and the excess is building up in the air. Carbon dioxide, the most prevalent greenhouse gas, builds up for a long time because it can persist in the atmosphere for more than 100 years.

To restore balance we need to find non-polluting energy solutions, get off fossil fuels and re-examine agriculture, too, because cattle contribute a potent greenhouse gas, methane, Prinn said.

What happens if we don’t?

“If we decide to do nothing for the next 90 years, if we decided that we don’t care about global warming, we can increase this (carbon) number by factors of two to three.”

You mean it would…”Yes, a doubling or tripling.”

Dr. Ronald Prinn, director of the MIT Center for Global Change Science

In terms of temperature, that amount of carbon in the air would mean Earth would be on average about 10 degrees Centigrade warmer by 2100 or – get ready to be singed – 18 to 20 degrees Fahrenheit.

This new, hotter prognosis is the result of recent analysis, published on MIT’s website in May, showing that global warming is occurring much faster than previously thought.

Under such change, both arctic poles would be nearly or completely melted. Their extinction would mean the oceans would rise dramatically, enough to put Bangladesh under water – along with parts of Florida and significant portions of both US coastlines.

Calamitous changes would face areas in the Southwest US and Mexico which would be too hot and dry for many crops; border disputes would break out across the globe between nations fighting over water and arable land.

“I think that for us to do nothing about this issue would be irresponsible to future generations, it would be saying we don’t care,’’ says Prinn. “In fact the people who would see this happening would be children born today, it’s a good chance at least in the rich countries they’ll be alive in 2100. Significant fractions of them will experience these big changes and stresses on the planet.”

And yet, “one has to be careful not to say that this would be the end of humanity.”

To a scientist, says Prinn, this is a problem requiring immediate action, but not one that calls for panic or incendiary rhetoric.

We have to take it a step at a time. First we slow the meter, he says. Then we stabilize it. Then we try to turn it back.

Our generation’s job is to slow it, to examine the 20 or so low-emissions energy solutions on the table – nuclear power, wind power, solar generation, conservation – and move in the right direction.

Then the next generation can use the latest technology, which could be much improved, to roll the numbers back in coming decades.

It took awhile for Earth to get to this point, he said. Carbon dioxide, the most abundant and one of the most persistent greenhouse gases can reside in the atmosphere for 120 years; methane, the second most significant greenhouse gases, can last nine years. So it will take many changes to work off the overload.

“Under no circumstances is this to say it’s the end of humanity,’’ reiterates Prinn. “It is a wake-up call. It’s time to slow that counter down and make it steady. Then we can talk about lowering it.”