Despite devastating rains a week ago and the approach of a tropical storm, Costa Rica and all of Central America continues to experience drought conditions. The reason is El Niño conditions in the Pacific that can result in the destruction of crops, less electricity and more fires, according to meteorologists at the Instituto Meteorológico National.
“I think we will have problems with agriculture and the generation of hydroelectricity because we don’t have water. Also, I think we will have a lot of fires in February or March of next year. All these effects are related to El Niño,” said Werner Stolz España, the chief forecaster.
The El Niño condition warms the ocean temperature and brings higher air surface pressures, which causes less rains in Central America.
“We will have an El Niño phenomenon this year. When we have this phenomenon, the important thing to notice is the precipitation. When you have El Niño, you don’t have rain. This is typical, and the effects are very, very strong, not just here in Costa Rica but in all Central America. It’s very,very dry conditions in Central America,” said Stolz in an interview.
As of July 27, San José had 12 days without rain. This lack of rain has been typical across Central America with regions experiencing a surplus of dry days. The Caribbean has had the most rain, with Limón having 15 percent of the total amount of rain in the country at that time, the institute said.
“This July is a record of drought. We have in San José this moment about 30 millimeters of rain. That’s about 10 percent of the normal value for this month. We have a very strong deficit of rain not only in the Central Valley but Guanacaste too. In Liberia we had 22 dry days. This is a characteristic of all Central America. In the last five weeks, El Salvador has had 30 dry days,” said Stolz.
He was speaking before a low pressure system drenched the Caribbean, Turrialba and the northern zone.
Despite the heavy downpours in the Caribbean mountains, the Central Valley, the Pacific coast and farmers in Guanacaste could have used more rain.
The cantons to the south of the province of Puntarenas, Golfito and Corredores, are the only places without rain less than the average. The average general deficit was 30 percent for the country. In the Central Valley the deficit increased from 7 percent in May to 30 percent in June, according to institute statistics.
As the days get drier, the temperature is increasing and the wind patterns are changing, the forecaster said..
“Another thing that is very significant is the temperature. We have two or three more degrees than the average. That’s very, very hot days. We have an abnormal wind. Very strong winds all day. When we have strong winds, we don’t have rain in
Central and Pacific parts of the country,” said Stolz.
El Niño started in June and is predicted to last seven or eight months.
The weather institute has a technical group called the El Niño commission. This group talks about the behavior of weather and implements mitigation plans to help the country deal with El Niño. The commission has already set a plan up for this year.
All the data is compiled into a monthly report by the meteorologist at the Instituto Meteorológico Nacional.
On a daily basis, this group handles the weather forecast for both the continental and maritime parts of the country.
The team of six persons run the weather data through three model forecast systems. They are the Global Forecast System and Weather Research and Forecast System from the United States and the ETA model, based on the seventh letter of the Greek alphabet, from Brazil.
Next, the team receives three satellite images that gives members pictures of the clouds all over the country. Automatic meteorological stations give them a readout for the wind, relative humidity, temperature, atmospheric pressure, rain and solar radiation.
With the data, the team conducts weather briefings to create the forecast for the current and next day. Despite changing conditions in Costa Rica and the unstableness of the tropics, the weather report is usually 75 percent accurate, the forecaster said.
“We have a global view of the atmosphere of the country and around Central America. With this picture we can defect hurricanes in real time. We receive images each 30 minutes. We can see in advance hurricanes, tropical waves, tropical storms, heavy rains, cold fronts from the North American countries. We see these images and compare with maps generated with the General Forecast System,” said Stolz.
A radiosonde is sent up everyday at 6 a.m. from Alajuela to predict thunderstorms.
“We launch a radiosonde to do predictions of thunderstorms. We can see with this graphic if the atmosphere is stable or unstable. It’s a good product because we have real data of our atmosphere, but it’s very expensive. It costs about $200 a day to run.”
Meteorologists at the institute are trained at the Universidad de Costa Rica. The university offers a bachelor’s degree, licenciatura, master’s degree and post-doctorate degrees in atmosphere science.
In the event of a national disaster, the country has the national emergency commission to provide aid.
“They are similar to Fema in the United States,” said Stoltz, referring to the Federal Emergency Management Agency. “They attend to all the floods, earthquakes and so on.”