White weather balloons that some Costa Ricans mistook for UFOs (TT, Jan. 20), and daily launchings of a high-altitude aircraft from Juan Santamaría International Airport are expected to shed light on the phenomena of global warming and ozone layer depletion, as part of a mission by the U.S. National Aeronautics and Space Administration (NASA) in collaboration with Costa Rican experts.
The Costa Rica Aura Validation Experiment (CR-AVE), a three-point project, aims to validate information gathered by NASA s Earth-observing Aura satellite, launched in 2004, through two other methods, according to Jorge Andrés Díaz, director of the national remote sensor and aero-transporter investigation program of the National Center for High Technology (CENAT).
The weather balloons, or radio probes, and the NASA WB-57F aircraft that started taking off from JuanSantamaríaAirport last month, will gather data to validate information obtained from the satellite, Díaz said.
The mission, involving 130 scientists and 30 students from the University of Costa Rica (UCR) and Universidad Nacional (UNA), started Jan. 1, when students launched the first weather balloons, and will extend until Feb. 28, when the last probes will be launched.
Four biodegradable probes that measure ozone, water vapor, temperature, humidity and wind speed, and can reach an altitude of 100,000 feet, will be launched daily at six-hour intervals during this time, he said.
The probes, made of latex, eventually pop and fall into the ocean, where they disintegrate, Díaz explained.
A NASA aircraft blasted off from the National Hangar for Airborne Research, at the remote terminal at JuanSantamaríaInternationalAirport in the province of Alajuela, on Jan. 14.
From that day until Feb. 12, the NASA aircraft will make 12 or more flights, with one launch each day, NASA scientist Eric Jensen told journalists during a press conference before takeoff.
The aircraft can reach an altitude of 60,000 feet, approximately twice as much as a commercial aircraft, requiring its two pilots to wear spacesuits because of the low air density, which NASA scientist Paul Newman said is 5% of the density on land.
The small but large-winged aircraft will carry 29 instruments to confirm insights regarding ozone depletion in the tropics, Jensen announced at the press conference, during which U.S. Ambassador Mark Langdale and Fernando Gutiérrez, Costa Rican Minister of Science and Technology, also delivered speeches.
It will measure high-altitude clouds, showing how clouds change with pollution, Jensen explained.
Although CENAT s Díaz said the project will not have a direct impact on global warming and ozone layer depletion, he said it will yield understanding about the processes.
According to Jensen, high-altitude ice cloud formations may indirectly affect the amount of sunlight that reaches earth.
A team of biologists in Costa Rica last month published a study in the famed British journal Nature linking this cloud-cover, attributable to global warming, to the extinction of two frog species in the country and the reduction of amphibian populations in general (TT, Jan. 20).
Results of the NASA study are expected one to two years after obtaining preliminary insights at the end of this campaign, according to Newman.
Last year, another NASA mission in Costa Rica used similar weather balloons and a high-altitude aircraft, NASA s ER-2, to conduct hurricane research in the country (TT, July 1, 2005).
Costa Rica built the hangar at Juan Santamaría in 2001 to attract U.S. research campaigns in the future, according to a statement from the U.S. Embassy in San José.
Since then, seven NASA missions have used the facilities, including the Aura Validation Experiment.
