Climate Science

ACS is committed to promoting awareness about climate science.

What Is Climate Science?

Climate in a narrow sense is usually defined as the “average weather,” or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period ranging from months to thousands or millions of years. The classical period is 30 years, as defined by the World Meteorological Organization. These quantities are most often surface variables such as temperature, precipitation, and wind.

What Is Climate Science

Why It Matters

2 ºF

Global temperature is up by 2 F since 1880

428 bn Mt

Ice sheets lose 428 billion metric tons of ice every year

414 ppm

Carbon dioxide is up at 415 parts per million

13.1%

Arctic ice is lost at 13.1 percent each decade

3.3mm

Sea levels rise 3.3 millimeters every year

Civilization as we know it is entirely dependent on burning fossil fuels—which are, in reality, fossilized sunshine—cheaply. Humans use fossil fuels cheaply because we treat the atmosphere as a cost-free dumping ground for the waste products of fossil fuel combustion, primarily carbon dioxide.

Earth’s climate will not tolerate the continued unconstrained use of fossil fuels. The atmospheric concentration of carbon dioxide has increased from 280 parts per million prior to the Industrial Revolution to more than 400 ppm today. As a result, Earth’s average temperature has increased by about 1 °C (1.8 °F). Models suggest that if atmospheric carbon dioxide doubles from preindustrial levels, Earth’s temperature could climb as much as 3.5–4.5 °C (6.3–8.1 °F), which would trigger catastrophic heat waves and ocean level rise and render many regions of the Earth unlivable.