Over the past five decades – and as the climate warms – prolonged periods of winter cold In Puerto Rico have been reducedwhich has consequences in areas such as agriculture and the control of disease vector populations.
A recent analysis of the independent organization Climate Centralwhich examined winter cold spells in 240 locations in USA between 1970 and 2023, he found that these periods, in San Juan, decreased by four days.
First of all, the report findings reaffirm “that we have changed the climate”stressed the climatologist Rafael Mendez Tejedawho has studied the increase in hot days in the archipelago.
The report warned that, in 98% of the places studied, the longest cold spells in winter have been shortened, and cold periods have been reduced by six days on average.
The analysis of Climate Central – an entity that is dedicated to studying and reporting on the climate change– defines a cold winter spell as, “at least two consecutive days from December to February with average temperatures below the normal average winter temperature of 1991-2020 at that location.”
Méndez Tejeda mentioned that “We must take into consideration that the temperature variation in the United States is greater than in Puerto Rico”since the differences in the archipelago are less extreme.
The conclusions of the analysis add to other research on increases in temperature. A previous analysis by Climate Central showed that the nights and early mornings in Puerto Rico they have become warmer. Specifically, between 1970 and 2020, the minimum temperature in San Juan registered an increase of 3.4 degrees.
Meanwhile, a study by Méndez Tejeda, published in 2017, concluded that hot days have practically tripled compared to cold days. Also, he found that, between 1950 and 2014, the temperature in the archipelago has increased 8 degrees Fahrenheit.
This increase responds to the rise in ocean temperature and greenhouse gases, which contribute to climate change. He greenhouse effect refers to how heat is trapped in the atmosphere by these gases, which include carbon dioxide, methane, nitrous oxides, and water vapor.
“The pollution we have had in the atmosphere causes the Earth to continue warming, because the atmosphere cannot cool down”highlighted Méndez Tejeda.
For its part, Emanuel Rodriguezmeteorologist National Weather Service (SNM), pointed out that there are a clear trend that the temperatures recorded at the San Juan meteorological station, active since 1899, have increased over time.
2023 was the hottest year in the history of the Earth and the third warmest recorded in Puerto Rico, with an average temperature of 82.2 degrees Fahrenheit. By comparison, the hottest years in the archipelago were 1983 and 1980, both with an average temperature of 82.3 degrees Fahrenheit, according to SNM data.
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The outlook, until at least the beginning of summer, does not look better ”Emanuel Rodríguez, meteorologist
Last January ended as the second hottest on record, at 80.1 degrees Fahrenheit. The year that recorded the hottest January was 2014, when the average temperature reached 80.2 degrees Fahrenheit, the meteorologist said.
And it is expected that the next few months the temperature will also be warmer than usual.
“Last year, we had a maritime heat wave, which has not ended. What this produced is that, from May until today, we continue to see temperatures above average. The outlook, until at least the beginning of summer, does not look better. It should remain warmer than usual, except for some days that are very cloudy or very rainy,” Rodríguez explained.
Climate Central warned that shorter winter cold spells have consequences that extend into spring and summer. In agriculture, for example, these sustained periods are important for certain crops and guarantee the production of fruits in spring and summer.
Furthermore, the temperature influences the reproduction of some animals. Cold periods, in fact, serve to control populations of disease vectors, such as mosquitoes and ticks.
“What would it mean if we have been hot since January or February? “That we are going to have greater mosquito infestations, that we are going to have a greater number of insects”stressed Méndez Tejeda.
In the future, the climatologist warned that cold days are expected to continue to reducewhile the periods of hot days lengthen.
“The trend is to have a few cold days a year, but those few days are colder,” warned Méndez Tejeda. “And while, in the winter, the number of hot days is going to be extensive, winter is moving to technically disappear into spring and spring into summer.”