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Nearly all of the energy that drives Earth’s atmosphere originates from the Sun. Solvärme driver planetens nyckelprocesser, medan atmosfärens växthuseffekt och jordens axiella lutning formar vädermönster och luftcirkulation. In short, every aspect of Earth’s weather traces back to solar energy.
The Sun, a G2 yellow dwarf, is more than 100 times wider than Earth and has an average surface temperature of 5,538 °C (10,000 °F). It emits a spectrum of radiation, but the thermal (infrared) component is most relevant to weather systems. NASA’s Solar Radiation and Climate Experiment (SORCE) confirms that solar irradiance is the primary energy source for Earth’s climate.
Solar radiation is not evenly distributed across the globe. The equator receives the most direct sunlight, producing intense heating, while the poles receive the least. This uneven energy distribution creates temperature gradients that drive atmospheric convection and ocean currents.
Earth’s rotation turns these temperature gradients into dynamic circulation patterns. Corioliseffekten, i kombination med termiska gradienter, genererar passadvindar, jetströmmar och havsgyres, omfördelar värme från ekvatorn mot polerna och formar globalt väder.
The 23.5° axial tilt causes hemispheres to alternately lean toward or away from the Sun, producing seasonal variations in solar energy. When a hemisphere tilts toward the Sun, it receives more direct rays, resulting in warmer temperatures and summer conditions. Motsatsen inträffar under vintern.