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What Is Climate Science

Polar bear on iceberg. Melting ice and global warming. Climate change. 3D illustration

Climate, derived from the Greek klima meaning “inclination,” is the weather averaged over a long period of time, typically 30 years. The Intergovernmental Panel on Climate Change definition is:

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.

Various localities have widely varying climates depending on many different variables. The climate of the Earth as a whole is the average of the various climates around the globe.

Climate science is the effort by humans to understand the natural forces that control the climate. A planet’s climate is driven by the energy of the Sun falling on the planet’s surface, which varies widely depending on latitude and the season. Climate is ultimately determined by the complex interplay between that energy and the Earth’s atmosphere, oceans, and land masses.

Climate science is not a new discipline. Scientists have been thinking about why the Earth has the temperature it does for at least 200 years, starting with work done by French mathematician and physicist Joseph Fourier in the 1820s, who speculated that the Earth’s atmosphere played a role in trapping heat energy being reradiated from the planet’s surface. The Irish chemist John Tyndall first showed that water vapor, carbon dioxide, and other gases absorbed infrared radiation in the 1850s. And the Swedish chemist Svante Arrhenius showed in the 1890s that the increasing concentration of carbon dioxide in the atmosphere from burning coal could result in the eventual warming of Earth. Today, highly accurate and complex computer models running on supercomputers accurately account for how climate responds to changing conditions.