Credit:  Microsoft Clip Arts

Credit: Microsoft Clip Arts

I am taking an online course on Climate Change from the University of Exeter in England. This was of special interest to me because my book (work in progress) is based on the premise of a new global ice age & how people would cope with this phenomenon.   Today was the first day of class & I found it really interesting.

Some of the things I learned today are the difference between weather (day to day or even hour to hour conditions around us such as the polar vortex my American friends have been complaining about so bitterly for the last week or so) & climate (generally a 30 year synopsis of the weather but it can be a much longer look at weather conditions on our planet).

I also learned about greenhouse gases (carbon dioxide, methane, ozone, water vapor, nitrous oxide & CFC’s) – what they are & how they effect our climate.  Greenhouse gases affect how the sun’s radiation is absorbed by the planet.  Small changes in greenhouse gases can have large changes on what happens to the sun’s radiation:

Not enough greenhouse effect:  The planet Mars has a very thin atmosphere, nearly all carbon dioxide.   Because of the low atmospheric pressure, and with little to no methane or water vapor to reinforce the weak greenhouse effect, Mars has a largely frozen surface that shows no evidence of life.*

Too much greenhouse effect:  The atmosphere of Venus, like Mars, is nearly all carbon dioxide.  But Venus has about 300 times as much carbon dioxide in its atmosphere as Earth and Mars do, producing a runaway greenhouse effect and a surface temperature hot enough to melt lead.*

*From IPCC

I’m looking forward to a lot more interesting information as the course continues.