2021 Heat Wave

	2021 Heat Wave This category is for heat waves in the year . Heat waves Heat In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is al ... {{Title year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
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picture info	Heat Wave A heat wave, or heatwave, is a period of excessively hot weather, which may be accompanied by high humidity, especially in oceanic climate countries. While definitions vary, a heat wave is usually measured relative to the usual climate in the area and relative to normal temperatures for the season. Temperatures that people from a hotter climate consider normal can be called a heat wave in a cooler area if they are outside the normal climate pattern for that area. The term is applied both to hot weather variations and to extraordinary spells of hot weather which may occur only once a century. Severe heat waves have caused catastrophic crop failures, thousands of deaths from hyperthermia, increased risk of wildfires in areas with drought, and widespread power outages due to increased use of air conditioning. A heat wave is considered extreme weather, and poses danger to human health because heat and sunlight overwhelm the human body's cooling system. Heat waves can usually be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]