In September, 2004 341 millimetres (13.4 in) mm of rain was recorded in Dhaka in 24 hours.In the Indian subcontinent, a cloudburst usually occurs when a monsoon cloud drifts northwards, from the Bay of Bengal or Arabian Sea across the plains, then onto the Himalayas and bursts, bringing rainfall as high as 75 millimetres per hour. The skillful forecasting of rainfall in hilly regions remains challenging due to the uncertainties in the interaction between the moisture convergence and the hilly terrain, the cloud microphysics, and the heating-cooling mechanisms at different atmospheric levels. Weather forecast models also face a similar challenge in simulating the clouds at a high resolution. While satellites are extensively useful in detecting large-scale weather systems and rainfall, the resolution of the precipitation radars of these satellites are usually smaller than the area of cloudbursts, and hence they go undetected. It is not essential that cloudbursts occur only when a cloud clashes with a solid body like a mountain, they can also occur when hot water vapor mingles into the cold resulting in sudden condensation. Rapid precipitation from cumulonimbus clouds is possible due to the Langmuir precipitation process in which large droplets can grow rapidly by coagulating with smaller droplets which fall down slowly. Cloudbursts are also responsible for flash flood creation. The results of cloudbursts can be disastrous. ĭuring a cloudburst, more than 20 millimetres (0.79 in) of rain may fall in a few minutes. The associated convective cloud can extend up to a height of 15 kilometres (9.3 mi) above the ground. the Swedish weather service SMHI defines the corresponding Swedish term "skyfall" as 1 millimetre (0.039 in) per minute for short bursts and 50 millimetres (2.0 in) per hour for longer rainfalls. However, different definitions are used, e.g. Rainfall rate equal to or greater than 100 millimetres (3.9 in) per hour is a cloudburst. ![]() Though this idea has since been disproven, the term remains in use. The term "cloudburst" arose from the notion that clouds were akin to water balloons and could burst, resulting in rapid precipitation. At times, a large amount of runoff from higher elevations is mistakenly conflated with a cloudburst. However, cloudbursts are infrequent as they occur only via the orographic lift or occasionally when a warm air parcel mixes with cooler air, resulting in sudden condensation. 25 mm of the precipitation corresponds to 25,000 metric tons per square kilometre (1 inch corresponds to 72,300 short tons over one square mile). Cloudbursts can quickly dump large amounts of water, e.g. ![]() A cloudburst is an extreme amount of precipitation in a short period of time, sometimes accompanied by hail and thunder, which is capable of creating flood conditions.
0 Comments
Leave a Reply. |