“Beyond 4 Degrees” Dr. David Karoly’s Assessment of Climate Change
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
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.
Karoly discusses the devastating effects of climate change on Australia
and the rest of the planet.
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.
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
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.
At the same time, the country is undergoing increasingly intense and
frequent heat waves.
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.
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.
recurring heat waves, droughts are also disturbing many parts of
Australia, leading to extremely destructive wildfires.