lightblueline

As Santa Barbara prepares to welcome James Hansen on February 5, we can read an interview he did which aired on February 2 on the program Living on Earth.

Dr. Hansen describes the scenario where ice sheet melting in the past resulted in a sea level rise at the rate of one meter every twenty years. When lightblueline talks about the vulnerability that climate change brings to coastal cities, this type of nonlinear process is precisely the target of our action. We are not predicting a seven meter rise in a century, even though this has happened in the past. We are predicting that the "business as usual" scenario of carbon generation will result in a global climate where we cannot be certain that the polar ice sheets will remain intact over the next several hundred years. The vulnerability to sea level rise is the same whether it takes seven decades or seventeen decades. We share a common future in Santa Barbrara that our children's children will face. We have only a few years to turn the situation around.

Here is an excerpt from the Hansen interview:

"CURWOOD: So your concern about the chance of loss of large sheets of ice and the considerable impact that that could have on sea level rise is echoed by, um, Ohio State University scientist Lonnie Thompson and he says that those issues are gorillas in the room that the IPCC isn't paying as much attention to as he thinks it ought to.

HANSEN: Well that's a very good point because IPCC addresses a lot of things but there are a small number which deserve very great attention. And this, I think, is the number one item just because of the inertia of the system. If we get it started it will become very difficult to stop it, perhaps impossible to stop it.

CURWOOD: Well, how do scientists relay the risk there when there is frankly a lot of uncertainty about what might happen?

HANSEN: Well, you know we do have a lot of information available to us both from paleoclimate; the history of the earth and how ice sheets responded in the past and also the new data from satellites, and on surface measurements on the ice sheets which shows that there are processes beginning to happen there, exactly the processes that we're afraid will accelerate. The last time a large ice sheet melted sea level went up at a rate of five meters per century. That's one meter every 20 years. And that is a kind of sea level rise, a rate which the simple ice sheet models available now just cannot produce because they don't have the physics in them to give you the rapid collapse that happens in a very nonlinear system."

You can read or listen to the whole interview here:

Living on Earth:Gorilla of Sea Level Rise