The Science

What is the climate threat?

With over 400 parts per million of CO2 in the atmosphere, Earth’s average temperature has already increased by about 1 degree Celsius since the industrial age began. Scientists and politicians agree that 2 degrees Celsius is the absolute limit, but globally greenhouse gas emissions continue to rise.This raises the probability of runaway feedback loops that would produce an irreversible shift to a new, hotter global climate, resulting in dramatic sea level rises, ocean acidification, devastation of coastal cities, and agricultural havoc.

Scientists have known for several decades that greenhouse gases such as CO2 and methane emitted by human activity (industry, transportation, home heating and electricity generation etc.) accumulate in the atmosphere and increase the greenhouse effect, which raises the average global temperature. As a result, arctic ice has been melting at alarming rates, sea levels are rising, and our oceans are acidifying. With over 400 parts per million of CO2 in the atmosphere, Earth’s average temperature has already increased by about 1 degree Celsius (3.6 Fahrenheit) since the industrial age began. Scientists and politicians agree that 2 degrees Celsius is the absolute limit, but globally greenhouse gas emissions continue to rise. This raises the probability of runaway feedback loops that would produce an irreversible shift to a new, hotter global climate, resulting in devastation of coastal cities and agricultural havoc. The scientific evidence is overwhelming.

 Resources about climate change

Climate Change. Evidence and Causes. From the National Academy of Sciences.