I am writing a series of articles talking about the causes and effects of climate change, and the three major industries that are contributing to greenhouse gas emissions that are causing climate change to occur (the energy sector, animal agriculture and the transportation industry).

Check out my article from last week to read about what climate change is and what is causing it.

This week, I'm tackling the effect the energy sector is having on the planet.

90 percent of the energy used in Americans’ everyday lives comes from non-renewable sources, such as coal and natural gas. Non-renewable energy sources are those which are not naturally replenished for a very, very long period of time after being extracted from the earth’s geosphere. When coal is burned to produce electricity, it emits carbon dioxide into the atmosphere. Natural gas is used for home heating, and it releases methane when it is extracted via hydraulic fracturing — aka fracking. Though methane is less common in the atmosphere than carbon dioxide, it is 86 times more potent of a greenhouse gas.

Coal and natural gas are the most prominent energy sources in the United States, and both are major greenhouse gas emitters.

Fortunately, there are alternatives to non-renewable fossil fuels. There are renewable energy sources available, including solar, wind and hydroelectric power. They do not emit greenhouse gases when used, and the power sources are virtually limitless. There is potential for the world to switch to 100 percent renewable energy sources, and some U.S. cities have already made the switch or have committed to it. San Francisco, California has committed to total renewable energy by 2030.

Mayor Ed Lee stated:

“We know that we are in a national city, a popular city, but we also want to be a city that contributes to the challenges of climate change and improves our world. If we can do that here, I suggest that we can do that anywhere.”

Cities such as Aspen, Colorado; Burlington, Vermont; and Greensburg, Kansas have already successfully transitioned to clean, green energy and have provided a model for other cities to follow — proving the environmental, economic and social benefits of the transition.

Check back next week for my next article on how animal agriculture is contributing to climate change.