5 August 2009

Climate Change in Your Backyard

Posted by Dan Satterfield

I’m involved on a conference call tomorrow with NOAA. It’s about the U.S. Global Change Report released earlier in the Summer. The call is to brief meteorologists in TV, and other weathercasters, about the contents of the report and to allow for questions about it.

Tom Karl, the head of the National Climate Data Center (and President of the AMS) will lead the call. Also on the call,  is Michael Savonis of the Federal Highway Administration. (Read the report linked below, and you will know why he is an important contributor.)

My small part is to talk about how to bring this information to the public on air, and online. (Yeah, I’m doing it now!) If you are an AMS Seal holder, or a weathercaster, who is a member of the American Meteorological Society in the Southeast USA, you probably have been contacted about it already.

Yes,  I know most of my readers here are not! (Much less in the Southeast USA) I will, however, put up the link here afterward, so you can listen to a recoding of the call. Most will likely hear it that way.

So, I thought I would share a couple of graphics from it here. This report marks one of the first instances where output from the global climate models has been down-scaled to estimate the actual changes, that will be seen in the next 80-90 years, if greenhouse gases continue to rise at the “business as usual” rate.

It’s a “here is what is likely to happen if we do not make major changes” report.  This report is the result of years of hard work by some very bright scientists.  They had to invent a new way of modeling the long term climate over a smaller region.

From IPCC Third Asses. Report. When CO2 increases are added into the models, they reproduce the past very well.

From IPCC Third Asses. Report. When CO2 increases are added into the models, they reproduce the past very well.

Global Climate Models (GCM’s) are  run for hundreds of years of model time, and unlike models I use everyday to predict the weather for the next few days, they have a very course resolution. If you made the GCM the same resolution as the weather models, it would take years to get a forecast out to 100 years!

This does not mean the GCM’s are no good. They actually present a stunningly accurate recreation of the past, but until now, we could not answer questions from viewers on the specific impacts in say Huntsville, Alabama, or New Orleans.

What the scientists did, was take the overall data from the GCM’s, and then apply those conditions to regional areas. They then ran the numbers using methods we already use with the higher resolution weather models.

One of these methods is called Model Output Statistics. (Wx geeks call it the MOS as in “on a rock”)  Simply put it looks at the model data, and predicts the high and low temperature. It does an amazingly good job most of the time.

So what does the future look like in climate terms. It’s NOT pretty. Here are two graphics from the report that speak for themselves. One shows how things have already changed. The second is what is to come.


The average number of days each year over 90 in Huntsville is expected to double. The number of days with very heavy rainfall has already increased by 20%.

When you get rid of the political propaganda  all over the internet these days, and just look at the Science, it’s a bit alarming isn’t it?