“Beyond 4 Degrees” Dr. David Karoly’s Assessment of Climate Change   
 
“Beyond 4 Degrees” Dr. David Karoly’s Assessment of Climate Change  
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Hallo, eco-friendly viewers, and welcome to Planet Earth: Our Loving Home. On this edition of our program we speak with renowned Australian climate scientist David Karoly.

David Karoly is professor of meteorology in the School of Earth Sciences at the University of Melbourne, Australia and an Australian Research Council Federation Fellow specializing in the fields of greenhouse climate change, ozone depletion and climate variations associated with the El Niño-Southern Oscillation.

An internationally-recognized expert on global warming, he is a member of the United Nations Intergovernmental Panel on Climate Change, a Co-coordinating Lead Author for the Panel’s 2001 Third Assessment Report, and a Lead Author for the Panel’s 2007 Fourth Assessment report as well as a review editor.

Today, Professor Karoly discusses the devastating effects of climate change on Australia and the rest of the planet.

Dr. Karoly (m): The summers of 2007,2008, 2009 had less sea ice in the Arctic than any other year. We’ve also seen increases in melting of the ice sheet in Greenland.
So what we’ve seen is increases in melting and the retreat of the glaciers.
So that the ice is moving faster down to the water. What that means potentially is destabilization of the Greenland Ice Sheet and more rapid melting of ice, which will contribute to faster sea level rise.

Dr. Karoly (m): We’re also seeing at high latitudes in the Northern Hemisphere on land, melting of permafrost areas, close to the surface of the ground that are permanently frozen that don’t actually melt in summertime.
 
And what we’re finding is those areas of frozen ground are actually melting for the first time in recorded history. That’s destabilizing buildings but it’s also having another amplifying feedback because trapped in this frozen ground are large amounts of essentially vegetation material and methane that’s trapped under the ground.

When it melts, it releases the methane and that also can amplify the rate of warming because methane is a very effective greenhouse gas, much more effective per kilogram of methane than carbon dioxide. So releasing methane from melting permafrost is another factor that increases the rate of climate change.

HOST: Global warming’s dangerous impact on Australia is becoming increasingly apparent with each passing year.

Dr. Karoly (m): Here in Australia we've experienced massive reductions in rainfall in the southeast and the southwest, which is having impacts on agriculture.

HOST: At the same time, the country is undergoing increasingly intense and frequent heat waves.

Dr. Karoly (m): We had in winter, in August, a heat wave not in this same area but in a different part of Australia, in Queensland and  New South Wales and then we again experienced record temperatures, records not just for 30 years or 50 years but records for the whole of the observational data for more than 100 years and the remarkable thing, this is really what surprised me and many other climate scientists, was that normally the hottest time of the year in most parts of the world is in summer.

Summer in Australia is January and February. The interesting thing is that there were a number of cities and towns that had their hottest day of the year in this heat wave in August, hotter than any time in January or February, the normal hottest time of the year.

So to have the hottest day of a year in the middle of winter is really unusual, it’s just unheard of in many of these areas.      

HOST: Besides recurring heat waves, droughts are also disturbing many parts of Australia, leading to extremely destructive wildfires.

For more information on Professor David Karoly,
please visit
www.EarthSci.UniMelb.edu.au

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