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Global Warming Winter Storming. Ellen E. Martin Dept of Geological Sciences. Snow angel Ocala , Florida, Jan. 8, 2010. If global warming is really happening… Why was this winter so cold and wet? Winter 2010 -second coldest winter on record in Florida. Need to understand:
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Global Warming Winter Storming Ellen E. Martin Dept of Geological Sciences Snow angel Ocala , Florida, Jan. 8, 2010
If global warming is really happening… • Why was this winter so cold and wet? • Winter 2010 -second coldest winter on record in Florida
Need to understand: • the difference between climate and weather • what :global warming” means Snowstorm in Washington DC, Feb. 2010
Climate vs. Weather • Weather • The state of the atmosphere at a given time and place with respect to temperature, cloudiness, moisture, wind,pressure • Climate • 30 year average of atmospheric state (World Meteorological Organization) • “expected weather”
Global Warming • A tendency for the global mean surface temperature to increase • Average: • Land and ocean • All latitudes • All seasons
Global Mean Temperature 58°F Mean Temperature- Gainesville 72°F
Measured temperature record for past ~150 yrs
Northern Hemisphere Temperatures for the past 1000 yrs Medieval Warmth Little Ice Age
Time series, Alaska Kilimanjaro, Africa
Arctic Sea Ice- summer 1979 2000 http://www.youtube.com/watch?v=JMQ21p93JZc NASA Goddard Space Flight Center
Whether the world is getting warmer isn’t controversial • Political debate focused on whether the world is getting warmer due to: • - natural causes • or • - man-made greenhouse gases (the greenhouse effect)
Colder More ice Centuries Millions of years Millennia Zachos et al., 2001
So, why was this winter so cold? • El Niño
Vancouver Conditions in US during El Niño winters Vancouver
Strong evidence that the global mean surface temperature of earth is increasing • Global warming = climate = global • Cold winter in southeast US = weather = local • Related to El Niño conditions El Nino La Nina
From Goddard Space Institute http://data.giss.nasa.gov/gistemp/
Record of atmospheric CO2 from ice cores Record of atmospheric CO2 from direct measurements (Hawaii)
GreenhouseGases Ice core data IPCC 2007
Ice Core CO2 Record Modern rate of increased compared to past 400 ky
Earth’s Greenhouse Atmosphere Incoming Short wave energy Outgoing Long wave energy sT4 (S/4)(1-a) Ts = 58°F Earth
Global Carbon Cycle 826 +3/yr Reforestation 7 Deforestation +0.5/yr +1.5/yr 40,000,000 NASA- earthobservatory (~1990)
CO2 by Country Per capita 2002
Fate of Anthropogenic CO2 Consume all fossil fuels (2300) 2100 ppmV CO2 (CCD) Kump, Kasting and Crane
Temperature- Greenhouse Gas Correlation Correlation between temperature and CO2 concentration NOAA/NCDC
Anthropogenic Greenhouse Gases Gases Processes IPCC 2007
Climate System Atmosphere Cryosphere -ice Biosphere - vegetation Geosphere - land Hydrosphere -ocean