What is climate?

The word climate derives from the Greek word κλιμα, or inclination. Climate, in fact, is partly determined by the inclination of the sun’s rays on the Earth’s surface, which varies with the latitude and seasons. The term “climate” is often used as a synonym of meteorological “weather” even though their meanings are quite different. Meteorological weather is the set of meteorological elements that characterize the atmosphere at a precise moment. If we look out of the window we can immediately see what the weather is like. The climate, instead, is defined as the “set of meteorological phenomena (e.g. temperature, precipitation, winds, etc.) that characterize the average state of the atmosphere at a particular point of the Earth’s surface”, (according to the definition given by J. Hann an Austrian meteorologist). Due to the extreme variability of meteorological parameters, the World Meteorological Organization has established that, in order to identify climatic characteristics, and therefore the “average state of the atmosphere”, of a particular location, the minimum duration of the historical time-series of meteorological data must be at least 30 years. The discipline that studies the climate, its elements and its factors, and classifies the types of climate is called climatology.

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    Icebergs, ice packs and glaciers

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    Mean sea level rise foreseen by IPCC

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    Desertification

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    Life-cycle of different gases in the atmosphere

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    Save the air

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  • air

    The greenhouse effect

    Look

    ecosystems

    Deforestation

    Look
  • air

    Albedo

    Look

    air

    Future scenarios of an increase in the temperature

    Look
  • air

    Icebergs, ice packs and glaciers

    Look

    air

    Mean sea level rise foreseen by IPCC

    Look

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