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Summary

DescriptionNASA cloudeffects.jpg	Deutsch: Hohe Wolken sind oft dünn und nicht sehr reflektierend. Sie lassen einen Großteil der Sonnenwärme durch, und da sie sehr hoch liegen, wo die Lufttemperatur bitterkalt ist, strahlen diese Wolken nicht viel Wärme ab. Die Tendenz hoher Wolken ist, die Erde zu erwärmen. Niedrige Wolken sind oft dicht und reflektieren viel Sonnenlicht zurück in den Weltraum. Sie liegen dabei auch niedriger in der Atmosphäre, wo Temperaturen wärmer sind, und strahlen deshalb mehr Wärme ab. Die Tendenz niedriger Wolken ist, die Erde zu kühlen. English: The main difference between high and low clouds is that the high clouds are colder. This means that they radiate less energy into space than the lower, warmer clouds. Therefore, high clouds work to "trap" more energy than the low clouds. High clouds are not good at reflecting shortwaves. But, they are very good at blocking longwaves. This also traps heat. Thus, high clouds will cause a warming of the Earth's surface. Low clouds are excellent reflectors. But, they don't stop the longwave energy from escaping to space. Therefore, low clouds help to cool the Earth.
Date	April 2004
Source	http://www.nasa.gov/audience/forstudents/5-8/features/F_The_Role_of_Clouds.html
Author	NASA
Other versions	Derivative works of this file: NASA cloudeffects.svg

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