what are heatwave disastrous impacts? нужен ответ

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Severe heat waves cause catastrophic crop failures, thousands of deaths from hyperthermia, and widespread power outages due to increased use of air conditioning.

Heat waves are the most lethal type of weather phenomenon, overall. Between 1992 and 2001, deaths from excessive heat in the United States numbered 2,190, compared with 880 deaths from floods and 150 from hurricanes.[10] The average annual number of fatalities directly attributed to heat in the United States is about 400.
In addition to physical stress, excessive heat causes psychological stress, to a degree which affects performance, and is also associated with an increase in violent crime.
Heat waves often lead to electricity spikes due to increased air conditioning use, which can create power outages, exacerbating the problem. During the 2006 North American heat wave, thousands of homes and businesses went without power, especially in California. In Los Angeles, electrical transformers failed, leaving thousands without power for as long as five days.[19] The 2009 South Eastern Australia Heat Wave caused the city of Melbourne, Australia to experience some major power disruptions which left over half a million people without power as the heat wave blew transformers and overloaded the power grid.
If a heat wave occurs during a drought, which dries out vegetation, it can contribute to bushfires and wildfires. During the disastrous heat wave that struck Europe in 2003, fires raged through Portugal, destroying over 3,010 square kilometres (1,160 sq mi) or 301,000 hectares (740,000 acres) of forest and 440 square kilometres (170 sq mi) or 44,000 hectares (110,000 acres) of agricultural land and causing an estimated €1 billion worth of damage.[20] High end farmlands have irrigation systems to back up crops with.
Heat waves can and do cause roads and highways to buckle, water lines to burst, power transformers to detonate, causing fires. See the 2006 North American heat wave article about heat waves causing physical damage.
http://en.wikipedia.org/wiki/Heat_wave