 In the transition from the last glacier ice age which ended 16,000 years ago to our present day, there was a short period of intense cold.  This event occurred 11,000 years ago and is known as the Younger Dryas event.  The event lasted 1000 years and temperatures dropped 7 degrees Celsius!

 The Younger Dryas caused the extinction of many large mammals across N. America including Saber Toothed Cats, Mammoths, and Mastodons.  One possible explanation is that warming temperatures shut down the Atlantic Conveyor creating a dramatic climate event lowering global temperatures.

 We are currently in an interglacial period. Past data would suggest that we should be heading into a cooling period however….

GasFormulaContribution Water VaporH2OH2O36 – 72% Carbon DioxideCO 2 9 – 26% MethaneCH 4 4 – 9% OzoneO3O3 3 -7%

 The atmospheric lifetime of CO2 is estimated to be between 30 to 95 years.  An increase in CO2 causes an increase in temperature resulting in an increase in water vapor. It is this water vapor that contributes to most of the warming.  Methane is 72 times stronger than CO2 at absorbing heat however it is present in smaller concentrations and has a shorter life in the atmosphere

 Climate change means different “things” for different regions of the world.  Higher latitudes will experience greater temperature changes.  Computer models forecast drier conditions for much of the western and central United States.