According to the Instituto Meteorológico Nacional (IMN), November 2023 ended as the hottest November since 1940. Luis Alvarado, a climatology expert, indicated that there was an increase of more than 1.0 °C above normal.
In terms of the national average temperature, the situation, in general, has remained the same since May. That is, the entire country has experienced warmer-than-normal conditions.
“However, if we look at the records for only November, this year presented an increase that positions it as the hottest on record, at least since 1940,” Alvarado said.
In addition, according to temperatures since 2013, the trend for this month has been upward, whereas previous years had lower-than-normal temperatures. However, it is in 2023 that, for the first time, the limit of 1.0 °C is exceeded.
According to experts, this increase was mainly due to the influence of the El Niño phenomenon, climate change, and the rise in temperatures of the Atlantic Ocean and Caribbean Sea. The European observatory Copernicus announced on December 7 that November 2023 was the warmest November on record worldwide.
“The surface air temperature shows that the warmest November was exceeded by 0.85°C. Additionally, new records have been consistently set since June 2023, with each month being the warmest on record,” the observatory reported.
According to experts, in the next three months, temperatures will be 1 to 2 degrees higher in Costa Rica. The Central Pacific, North Pacific, and Central Valley will be the regions that will experience the greatest increase.
On the other hand, in relation to rainfall for the previous month, deficits and surpluses were recorded. “The case that drew the most attention was the surplus of 88% in the province of Guanacaste, due to the fact that this is not usual during an El Niño phenomenon,” commented Alvarado.
The phenomenon that caused the impacts of El Niño not to manifest themselves well was the extraordinary warming of the waters of the Caribbean Sea since October. The sea is 1.5 degrees Celsius warmer than normal.
According to the specialist, when the Caribbean or the Atlantic warm up in this way, they usually have the opposite effect, which is less rainfall in the Pacific and more in the Caribbean.
