Our Earth’s Future – Climate Change
I just completed an online course about climate change offered by the American Museum of Natural History in New York City. The course is five modules and you have two weeks at you own pace to complete each module. Dr. Tillinger starts out by discussing simple questions. What is science? What is climate? The course goes on to explain in detail how the climate is created. For example the course explains how the tilt of the earth affects the seasons and the amount of sunlight received. It explains how the spinning of the earth affects winds and ocean currents. The greenhouse effect was explained and how our earth would be 60 degrees colder if not for greenhouse gases and how the burning of fossil fuels has caused an increase in these gases that force the system to change.
A module was dedicated to climate models. It explained forcings and feedbacks and how a small forcing with some positive feedback can have a large effect. Another module was dedicated to people and wildlife currently affected by climate change and strategies seeking to mitigate these problems. The last module is titled “Mitigate, Adapt, or Suffer” and discussed what could happen in the future. The biggest variable is how we will act in terms of releasing more greenhouse gases.
What stuck with me most was the module on how greenhouse gases are affecting the oceans. The warming of the ocean makes the ocean expand and raises the level of the sea. Melting ice sheets and glaciers change the salinity and density and that leads to changes in the shallow and deep ocean currents. The oceans absorb not only a tremendous amount of heat but also a tremendous amount of carbon dioxide. This absorbed carbon dioxide leads to ocean acidification.
The course cannot go into great detail on all aspects of climate but it did encourage me to investigate certain topics further. I was curious about the Milankovich cycles and how the changing shape of Earth’s orbit along with tilt and wobble play into the climate and where we are in those cycles.
If you are interested in the scientific aspects of climate change then I suggest a course such as this to gain a better understanding of this important topic.
Gary Keir
