The primary cause of global warming is burning fossil fuels for electricity. Fossil fuels are non-renewable resources found in the Earth’s crust, deriving from the prehistoric remains of plants and animals. Because of its high energy efficiency, burning these resources is the most common form of producing electricity. However, burning fossil fuels has drastic effects on our environment. Because toxic air pollutants are released into the atmosphere, the main being carbon dioxide, it creates a phenomenon known as the greenhouse effect. The greenhouse effect occurs when large quantities of greenhouse gasses, namely carbon dioxide, are released into the atmosphere which generates heat. Over the past couple of centuries, the greenhouse effect has gradually increased Earth’s temperatures resulting in what we know today as global warming.