Global Warming

Effects of climate change on agriculture
Agriculture is outside his area, he has looked at a lot of agriculture.
Average global temperatures: 30 second video put out by NASA. Year will change, colors indicate if they were warmer or cooler during the reference period (1950-1980).... Most places were cooler in 1984 than in 1980. This is what the thermometers tell us. Goes through 2012. We all know that the earth is warming.
First period of warming: 1900-1940
Starting in 1970 - current period of warming, much more rapid.
This winter in Michigan has been unusual.
Natural Variation cannot explain current warming.
The cause of the warming is not the same both times.
When people say it is due to natural variation they say that the earth is receiving more energy from the sun.
Recently, while Earth had been warming fastest solar change has decreased.
This warming period is different than any in the last 800,000 years.
        1. Its at least 10-20 times faster (Than in the last 8 cycles)
        2. It's happening while solar input is decreasing.
>95% of current warming is due to human activities
        1. Fossil Fuels use (85%)
        2. Cutting down Forests -- Takes away carbon sponge (15-20%)
If we remain on our current course future climate change will be severe
Will a 5 degree temperature rise matter?
YES.
We don't know what will happen when it was 5 degrees warmer
If it is 5 degrees cooler we know what happens because it makes a huge difference for life on earth.
About 40% of the Earths surface is used for cropland and pasture
-- About 25% of land surface is too dry for agriculture use.
UN food and agriculture organization estimates 1.02 billion hungry people worldwide
How might climate change affect agriculture?
      1. Increase yields due to
          -CO2 ferilization effect (corn is not effected, but it does effect soybeans, rice, and wheat)
          -Longer growing seasons
      2. Decrease yields due to
          -Increased temperatures
          -Increased droughts
          -Increased flooding
          -Decreased nutritional quality
          -Pest problems
          -Decreased irrigation
Much of the US has been experiencing a severe drought
Severe rainstorms have already become more common.
Flooding is also likely to reduce future yields.
Crop pests are likely to increase with warming
To some extent adaptation measures can mitigate the adverse effects of climate change: Irrigation, planting dates,
Next time buy a fuel efficient car.
Wind power in Michigan could supply 12 times current statewide electricity demand
A small portion of the Sahara desert could supply all of the world's electricity.
The true costs of wind and solar are already lower than coal-generated electricity.