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This episode is a presentation of climate science and how we know global warming is happening. The 3 speakers are all scientists and climate experts. This was titled the Science of Climate change, and was presented last week by the Center for American Progress. You can see the entire video at the CFAP website here. You can download their slides there also. (Michael MacCracken’s slides were especially good.)

Basically, they discuss climate change science and risk management, as well as some of the finer points on how the IPCC publishes its data. There is a question and answer session at the end. They write on the CFAP site:

An overwhelming quantity of direct observations and analyses published by scientists in various disciplines around the world demonstrates that human activity has warmed the planet and altered the climate. The severity of the projected impacts of continuing on our current greenhouse gas emissions path has only increased in recent years.

The speakers are Christopher Field, of the Carnegie Institution of Washington, and Professor of Biology and Environmental Earth System Science at Stanford University, and a coordinating lead author for the IPCC’s Fourth Assessment. The second is Michael MacCracken, Chief Scientist for Climate Change Programs, Climate Institute, and co-author/contributing author for various chapters in the IPCC assessment reports. The event was moderated by Joe Romm, Senior Fellow, Center for American Progress and prolific blogger at ClimateProgress.org.

Some of their initial points about how we know climate change is happening:

• Average ground temperatures are going up
• Ocean temperatures are going up
• Sea ice cover is decreasing
• Mountain glaciers and permafrost are melting
• Sea level is rising
• A lot of plant and animal species are moving
• Arctic sea ice is retreating

You can download this episode here, or listen below or subscribe on the right.