“…It is important to note that since 2012, we did not have a season that exceeded 16 cyclonic events such as hurricanes or tropical storms”

Last November the hurricane season officially ended; without doubt one of the most devastating of recent times. The balance shows that it has been clearly one of the most critical in terms of the number of extreme weather events, such as tropical storms, hurricanes, and cyclones, as well as in terms of destruction in the Atlantic zone, the Caribbean Sea, and the Gulf of Mexico.

One of the most prolific seasons in tropical storms left 17 tropical storms, of which 10 of them became hurricanes, six of major category, classified by the speed of their extreme winds, and the rest categorized either as three, four or five.

“It has been one of the busiest seasons of recent years; it could even be along the seventh position of the strongest seasons in history. It is important to note that since 2012, we did not have a season that exceeded 16 cyclonic events such as hurricanes or tropical storms”, indicated the director of forecasts of the Institute of Hydrology, Meteorology and Environmental Studies from Colombia, IDEAM, Christian Euscátegui.

Hurricane seasons are classified through the “accumulated cyclonic energy index”, which is the result of measuring the combined intensity and the length of the storms. According to the National Oceanic and Atmospheric Administration, NOAA, this 2017 season has been the seventh most active in history, according to the record that has been registered since the mid-nineteenth century in 1851 and is the strongest since 2005.

The intensity of a storm season is not necessarily directly related to the degree of destruction it generates; during some seasons, tropical storms and hurricanes do not touch land, thus the destruction is considerably reduced. Euscátegui points out that “beyond being one of the most prolific seasons of recent years, it was also one of the most destructive; it will always be remembered by Harvey, Irma and María”.

Facing the increase in strength, intensity, and number of extreme weather events, we tend to think that, thanks to climate change, the tendency is that each year the season will be much stronger than the previous year; however, the head of forecasts at IDEAM indicated that “Climate change could have an influence on this season, however, it is important to mention that in order to be able to assert it, we must do deeper studies; it is not correct to attribute everything to climate change before obtaining enough scientific evidence to be able to confirm  it with all certainty”.

He adds that “there is not necessarily a tendency for each season to be stronger; the 2018 season will not necessarily be more intense and destructive than that of 2017. What can be warned, with absolute certainty, is that to the extent that ocean waters in the Caribbean Sea and the Atlantic Ocean become warmer, there will be a greater probability of having a more intense season, which should be acknowledged by the risk management entities of the different countries and therefore be prepared in advance for the likelihood of this type of events will occur “.

Rare and new climatic events in 2017

The year 2017 was not only marked by one of the strongest hurricane seasons in history, but it also provided evidence of rare phenomena never seen before. Such rare events can also lead to think about extreme changes in the behavior of ocean temperatures.

Irma is the first tropical storm in history that climbs to the category of hurricane in the Atlantic Ocean before reaching the Caribbean Sea, where the waters are warmer, according to Patrick Galois from Météo France, the French meteorological service.

Irma also breaks all records of duration; more than 33 hours with winds exceeding 295 km / h, basic condition to be categorized in five (5), the maximum position of the Saffir-Simpson scale (the scale in which climatic events are measured). In the past, the longest extreme climatic event ever recorded was Typhoon Haiyan, which in 2013 left more than seven thousand dead in the Philippine archipelago.

Not only Irma was the first to form in the Atlantic and the longest in category five, but according to the Center for Disaster Management and Technological Risk Reduction in Karlsruhe, Germany, it was the most devastating hurricane in economic terms, leaving material losses for over $10 billion dollars.

Furthermore, and to sum up, Harvey also broke records regarding the amount of water rain; while hurricanes usually move at an average speed of 25/30 km / h, Harvey was stuck on the city of Houston. In the capital of Texas, the fourth most populated city in the United States, the highest rainfall ever recorded was 1,219 mm, occurred in 1978 thanks to Tropical Storm Amelia; Harvey, however, contributed a new rainfall record with 1,252 mm according to the National Hurricane Center.

Finally, Irma and José became the first two simultaneous active hurricanes of category four; situation that did not occurred since 2010 and that previously had only appeared in 1935.

Puerto Rico, Barbuda, Dominica, South Florida, Houston, and other places in the Caribbean and the Gulf of Mexico were destroyed by the onslaught of a strong 2017 season; reason why the names of Harvey, María, and Irma will never be heard again. Hurricane lists, generated by the Atlantic, Caribbean Sea and Gulf of Mexico Hurricane Committee, composed by all countries in the Caribbean, Central America, northern South America, and the southern United States, have decided that, thanks to its evident destruction, never again will a hurricane be known by those names.

Latin American Post | Alberto Castaño Camacho

Copy edited by Susana Cicchetto