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("Greenhouse Effect" OR "Växthuseffekt") 1650+ documents
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What does (greenhouse Effect Or Växthuseffekt) mean? Let's check what the community at Wikipedia thinks
På svenska: Denna artikel behandlar endast växthuseffekten som fysikaliskt fenomen. Att senare tiders klimatförändringar främst beror på människans utsläpp av växthusgaser behandlas i artikeln global uppvärmning.Växthuseffekten (eller drivhuseffekten) är den uppvärmning av jordytan som åstadkoms av jordens atmosfär. Effekten beror på att en del av den värme som strålar ut från jordytan värmer upp luften i atmosfären i stället för att stråla ut i rymden. Jorden blir därigenom varmare än den skulle ha varit om den hade saknat atmosfär. I större eller mindre grad uppträder samma effekt också på andra planeter som är försedda med atmosfär. Lär dig mer på Wikipedia
In English: The greenhouse effect occurs when greenhouse gases in a planet's atmosphere trap some of the heat radiated from the planet's surface, raising its temperature. This process happens because stars emit shortwave radiation that passes through greenhouse gases, but planets emit longwave radiation that is partly absorbed by greenhouse gases. That difference reduces the rate at which a planet can cool off in response to being warmed by its host star. Adding to greenhouse gases further reduces the rate a planet emits radiation to space, raising its average surface temperature. The Earth's average surface temperature would be about −18 °C (−0.4 °F) without the greenhouse effect, compared to Earth's 20th century average of about 14 °C (57 °F), or a more recent average of about 15 °C (59 °F). In addition to naturally present greenhouse gases, burning of fossil fuels has increased amounts of carbon dioxide and methane in the atmosphere. As a result, global warming of about 1.2 °C (2.2 °F) has occurred since the industrial revolution, with the global average surface temperature increasing at a rate of 0.18 °C (0.32 °F) per decade since 1981.The wavelengths of radiation emitted by the Sun and Earth differ because their surface temperatures are different. The Sun has a surface temperature of 5,500 °C (9,900 °F), so it emits most of its energy as shortwave radiation in near-infrared and visible wavelengths (as sunlight). In contrast, Earth's surface has a much lower temperature, so it emits longwave radiation at mid- and far-infrared wavelengths (sometimes called thermal radiation or radiated heat). A gas is a greenhouse gas if it absorbs longwave radiation. Earth's atmosphere absorbs only 23% of incoming shortwave radiation, but absorbs 90% of the longwave radiation emitted by the surface, thus accumulating energy and warming the Earth's surface. Learn more at Wikipedia
