Signs of Climate change OLLI WEST: EARTH CLIMATE – WEEK 4 Signs of Climate change Tuesday October 7th, 2014 Paul E. Belanger, Ph.D.

OLLI WEST: Signs of Climate change Last weeks field trip / web page and slides PowerPoint of week 3 – cover elements today Signs of climate change: Past Present Future CO2 emissions; CH4 emissions

OLLI WEST: Signs of Climate change (cont.) We are changing the climate: CO2 CH4 And resulting temperatures

Climate Changes from Ocean Sediment Cores, since 5 Ma Climate Changes from Ocean Sediment Cores, since 5 Ma. Milankovitch Cycles the last time inferred temperatures will have been this high – once equilibrium is reached, will have been 3-5 million years ago or more 41K 100 K * we are now about here 3.0Ma 4.0Ma 2.0Ma 1.0Ma 5.0Ma When CO2 levels get below ~400-600 ppm Orbital parameters become more important than CO2

U.S. CO2 Emissions have come down http://www.texog.com/blog/2012/07/23/shale-boom-helps-us-achieve-largest-co2-reductions-in-the-world/ http://www.c2es.org/facts-figures/us-emissions/electric-power

Lest we forget: CO2 is still going up * 400 ppm http://en.wikipedia.org/wiki/Keeling_Curve

What about Methane? http://www.esrl.noaa.gov/gmd/aggi/aggi.html http://clathrates.blogspot.com/2012/04/threat-of-methane-release-from.html