Tropical cyclone pools

The Northwest Pacific Basin is the most active on the planet. On average, 25.7 tropical cyclones of tropical storm forces occur here each year or more (about a third of all), among them, between 1968 and 1989 , an average of 16 reached typhoon strength ^[3] . This basin occupies a vast territory north of the equator and west of the 180th meridian , including the South China Sea ^[1] . This pool is active throughout the year, although the number of tropical cyclones that occur between February and March is minimal ^[4] .

Tropical cyclones of this basin often affect China , Japan , South Korea , the Philippines and Taiwan , to a lesser extent Vietnam , Indonesia and numerous islands of Oceania , and the continental coast of the PRC takes the first place in the world in the number of cyclones that land on land ^[5] . A large number of cyclones also affects the Philippines, where 6-7 tropical cyclones annually land on land ^[6] .

The Northeast Pacific Basin is divided into two parts, which are part of the area of ​​responsibility of various organizations.

The north-central Pacific sub-basin is located between 140 ° and 180 ° west longitude north of the equator ^[1] . The hurricane season here lasts from June 1 to November 30 ^[7] . The Central Pacific Hurricane Center ^{[1] is} responsible for warning of cyclones in this sub-basin, previously the Joint Hurricane Warning Center, now known as the United American Naval Typhoon Warning Center, performed this function. In this region, an average of 4-5 tropical cyclones occurs or enters the region annually ^[7] . Since there are no large land areas, cyclones rarely go to land, but this still happens sometimes, as in the case of Hurricane Inika, which went to Hawaii in 1992 ^[8] and Hurricane Ayoki, which went to Johnston Atoll in 2006 ^{[ 9]} .

The northeastern Pacific sub-basin is the second most active region and is characterized by the largest number of tropical cyclones per unit area. The hurricane season here lasts from May 15 to November 30 ^[10] . In the period 1971–2005, 15–16 tropical storms arose here annually, including 9 hurricanes and 4–5 strong hurricanes (from the 3rd category on the Saffir – Simpson scale ) ^[10] . Tropical cyclones in this area hit the west coast of Mexico and, less commonly, California or northern Central America. Although not a single hurricane in the modern period came to land in California, it may have happened with the 1858 hurricane in San Diego ^[11] ; Nevertheless, several hurricanes of the 20th century brought winds of at least 8 points on the Beaufort scale to this area ^[11] .

This pool includes the North Atlantic Ocean , the Caribbean and the Gulf of Mexico . The National Hurricane Center in Miami, which has the status of one of the regional specialized meteorological centers, is responsible for monitoring this pool ^[12] . The number of tropical cyclones here varies somewhat from year to year, usually ranging from 1 to 25 tropical storms per year ^[3] . On average, 11 tropical cyclones per year receive their own name, of which 6 reach hurricane strength, and 2 have a level of severe hurricane ^[13] . Most of these cyclones form from June 1 to November 30 .

Tropical cyclones in this area hit the Atlantic coast of the United States , Mexico , Central America , the West Indies and Bermuda , sometimes Venezuela and the islands of Macaronesia . Many of the strongest Atlantic hurricanes are Cape Verdian-type hurricanes that form off the west coast of Africa and the Cape Verde Islands . Sometimes tropical cyclones, which turn into extratropical , reach the shores of Europe, for example, such was the hurricane Gordon, which reached Spain and the British Isles in September 2006 ^[14] . Hurricane Vince, which land on land in southwestern Spain in October 2005 with the power of tropical depression, is the only tropical cyclone in the modern period that reached Europe as a tropical cyclone ^[15] .

This basin is divided into two halves by India and includes the Bay of Bengal and the Arabian Sea , of which the Bay of Bengal dominates in activity (5-6 times). In general, this pool is the least active in the world; only 4-6 tropical cyclones are formed here annually. The tropical cyclone season here has two peaks: in April – May, before the monsoons , and in October – November, immediately after the monsoons ^[16] . Although the number of tropical cyclones is relatively small, it was here that cyclones, record in the number of victims, were formed, in particular the 1970 Cyclone Bhol , which led to the death of 500 thousand people. The tropical cyclones of this basin affect India, Bangladesh, Sri Lanka, Thailand, Myanmar and Pakistan. Very rarely, tropical cyclones reach the Arabian Peninsula or Somalia , but the 2007 Gonu cyclone was one of these cyclones; it made significant damage in Oman .

In this basin, an average of 9 tropical cyclones are formed annually ^[3] . Very few of these cyclones reached category 5; one example was the Larry cyclone in 2006 ^[17] .

The activity of tropical cyclones in this area threatens the northern coast of Australia and the islands of Oceania. Tropical storms rarely reach southern Australia, such as Brisbane , or New Zealand , usually only fully or partially turning into an extratropical cyclone ^[18] .

Seven tropical cyclones occur annually in this basin, and sometimes tropical cyclones come from other basins, in particular from the South Pacific ^[3]. Only about 5 cyclones reach the fifth category every year ^{[19] [20]} .

The tropical activity of this basin threatens Australia and Indonesia . According to the Australian Bureau of Meteorology , a stretch of Western Australia from the city of Exmaus to the city of Broome is more likely to suffer ^[21] .

In this region, in 1999, the highest wind speed on Earth at 74 m / s was recorded within the boundaries of the Vance cyclone ^[22] .

Despite half a century of observations, the study of tropical cyclones became a priority of the regional specialized meteorological center on Reunion only since 1999 , when Meteo-France increased the center’s staff for this purpose ^[23] .

Cyclones forming in this basin can affect Madagascar , Mozambique , Mauritius , Reunion , Comoros , Tanzania and Kenya ^[23] . About 10 tropical cyclones form annually in this basin. The victims of tropical cyclones are very significant, on average up to 80 people die from them annually ^[3] .

In other areas, tropical cyclones form very rarely, so they do not belong to any officially defined basin.

South Atlantic Ocean

One of the areas where tropical cyclones sometimes occur is the southern part of the Atlantic Ocean. The only tropical storm cyclones in the area were the Katarina cyclone , which land on land in Brazil in 2004 , and the tropical storm Anita, land on land in Brazil in 2010 .

Mediterranean Sea

Sometimes cyclones , like tropical ones, occur in the Mediterranean Sea . However, whether they should be considered tropical cyclones is a subject of controversy, since they also have the features of subtropical cyclones and even polar depressions . These cyclones arise outside the tropics over the open sea from cyclones with a cold core, like subtropical cyclones of the Atlantic basin. The water temperature in August-September is quite high (from +24 to +28 ° C) to maintain a tropical cyclone, which requires minus a temperature of +20 ° C. Similar convection systems arose here in September 1947 , September 1969 , January 1982 , September 1983, and January 1995 . The last cyclone developed a clear eye of the storm and reached a wind speed of 40 m / s and atmospheric pressure of 975 mbar. Although it had the structure of a tropical cyclone, it existed at a surface temperature of 16 ° C, which indicates that it could be a polar depression ^[24] .