Articles by Andrew Dessler

Here’s why the scientific community thinks so

This is a "greatest hit" from my previous blog. It's a topic that comes up all the time, so I think it's worth a reprise.

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As George Bush said at a recent press conference: "the globe is warming. The fundamental debate: Is it manmade or natural?"

Why does the scientific community think humans are significantly contributing to today's warming?

To understand why, first recognize that whenever the climate shifts, there's a reason for it. It does not wander around like a drunken sailor.

Based on decades of research, we can identify the factors that have influenced climate in the past:

It’s time to move on

It's time for everyone to move past the Kyoto Protocol.

For those not familiar with the details, Kyoto imposes specific emission-reduction targets for each industrialized country over a five-year "commitment period" of 2008-2012. Targets were defined for total emissions of CO2 and five other greenhouse gases: the required emission reductions were 8 percent for the European Union and a few other European nations; 7 percent for the United States; 6 percent for Japan and Canada; and zero (i.e. hold emissions at their baseline level) for Russia and Ukraine. If all nations met their targets, the total emission reduction from these nations would be 5.2 percent below 1990 levels.

Should we worry about sudden climate shifts?

We hear a lot about climate "tipping points" in the news. You may very well be wondering what a tipping point is and whether it's something to be concerned about.

To understand a tipping point, imagine that you're sitting in a canoe and you start to lean your body over one side. The canoe will slowly rotate (I think the nautical term is "list") as you lean ever further -- until, that is, you lean just far enough, and suddenly the canoe flips over, sending you into the water. You've just encountered a tipping point.

The worry is that the climate will slowly warm as CO2 is added -- until we cross a tipping point, at which point the climate abruptly shifts into a new and possibly very different state. If this happens, it would likely be a disaster of Biblical proportions, unleashing unimaginable suffering and hardship.

It’s a poor indicator of progress on global warming

A recent news article about the Stern Report contained the following gem from a Bush administration spokeswoman:

The statement from spokeswoman Kristen Hellmer said the United States is "well on track to meet the president's goal to reduce greenhouse gas intensity of our economy 18 percent by 2012."

This statement makes it sound like the Bush administration is taking on the problem of climate change head-on, with an aggressive program to reduce emissions.

But it ain't so.