Past and Present Climates

This week has been extremely beneficial to understanding the past of the climate.  I was so astonished to see how far we could go in a class to seeing the earth and how little of a time humans have been on earth.  It really puts things into perspective for me.  I did not know that the earth is continuously flowing between a patter of cold and warm times and that we currently are in an ice age.  One thing I found particularly interesting was when we looked at the different aspects between the sun and the earth.  I learned that the change in distance between the energy intensity from the sun and the distance of the sun is not linear.  Rather, once there is a certain distance from the sun it is much colder and remains that way as the distance increases.  Another thing that I found interesting was the fact that 31% of solar radiation from the sun is reflected back into space.  I had no idea that the reflectivity of the surface (ex. changing the land from forests to a corn field) could make the earth more reflective.  I also had the idea that all greenhouse gas is bad but I learned that the greenhouse effect is responsible for 33 degrees Celsius for warming of the earth and that is critical to our survival.  Without this added warmed the earth would be at 18 degrees Celsius.  It was very helpful for me to get the big picture of climate change and to understand the patterns of earth’s climate.  It was also very informative to learn about the different ways in which we know about past climate.