on November 19. Until the end of October it was unremarkable season until Mid-Atlantic coast of the United States did not come out \»sandy\»… he Formally entered the land is not even a hurricane, as it did in August, \»Isaac\», devastated Southeast Louisiana and killed seven people. At the same time, \»sandy\» had a monstrous force equal to the energy of the five atomic bombs.
Officially, the hurricane season in the Atlantic ends November 30, but most likely, it already ended. According to the National center tracking hurricanes in Miami, for 162 years of observations of only five hurricanes hit the U.S. in the month of November. \»Now in the ocean there is no active region, can generate hurricane — continues the thought spokesman Center Dennis Feltgen.
This season has arisen 19 tropical storms and hurricanes, which is much higher than the average multiyear average (12). Out of the 19 storms 10 became hurricanes. Recall, a tropical storm becomes a hurricane when the wind steadily reaches 118 km/H.
Preseason predictions are a little different. So, the Colorado state University forecast of 13 storms, and 5 of them hurricanes, while the National office for the atmosphere and the ocean waited 15 storms, 7 of which could become hurricanes.
The team from Colorado state University participates in the preparation of forecasts for the hurricane season since 1984. \»It was a very unusual year, \» says meteorologist Phil Klotzbach from the University of Colorado, because there are a lot of tropical storms, but most of them were short-lived and weak.
Surprisingly, neither \»sandy\»or \»Isaac\» were not strong hurricanes — 3rd or more hazard category scale the Saffir-Simpson (>177 km/h). Only unremarkable \»Michael\» in September gained the force of a hurricane 3 category, and then only for a few hours, when he was in the open ocean, says a scientist from Colorado.
\»In theory, nobody would have never thought to predict this season, \» says Klotzbach, in which only 1 out of 10 storms became strong.\»
One of the factors that unexpectedly influenced the emergence of a large number of storms, was the failure of the development of the long-predicted El niño, the expert believes. El niño is manifested in the warming of tropical waters of the Pacific ocean and at the same time tend to suppress hurricane activity in the Atlantic basin.
This event is expected in the middle of hurricane season, but, according to the latest prediction Center climate forecasts NOAA, probably will not arrive this winter.
The season started vigorously, with four storms in may and June, that was the first time since 1851. In July, the ocean was completely silent, but then brought eight storms in August, setting a new record since 2004.
\»Isaac struck Louisiana on August 28 and brought damage to $ 2 billion. Only two tropical cyclone occurred in September, usually the most active month of the year month of the season, and none of them came to the United States.
As it turned out, it was all just a prelude to violence \»sandy\», which in the United States and 121 people were killed (only 199) and suffered damages in $ 50 billion. This hurricane was the second most costly natural disaster in U.S. history after hurricane Katrina in 2005.
\»Sandy came ashore in the area of Atlantic city (new Jersey), but not as a hurricane and post-tropical cyclone — a hybrid of hurricane and cyclone middle latitudes. The zone of influence of storm winds swept 1500 km of the Eastern coast of the US.
One measure of the activity of the hurricane season is \»the accumulated cyclone energy, or ACE (Accumulated Cyclone Energy). ACE is an indicator, which combines a number of factors, how long the cyclones exist, and what they have intensity.
\»ACE this year is 129 units, \» says Phil Klotzbach,whereas on average the figure is 92. The higher the value of the ACE (248 units) was noted in the record-breaking 2005, when raging hurricanes \»Katrina\», \»Rita\» and \»Wilma\».
As for the hurricane season in the Eastern Pacific, he was on the active side, with 17 storms, 10 of which became hurricanes. On average, there occurs 15 storms, eight of which are stronger hurricanes.