Scientists from the USA’s National Aeronautics and Space Administration (NASA) arrived last week in Namibia to observe and measure how aerosol particles interact with clouds and change their ability to warm or cool the earth.
The scientists will be based in Walvis Bay and will for the next three years work with students from the Namibia University of Science and Technology and scientists from the Gobabeb Research and Training Centre. Further, the university personnel will give logistical support in the fieldwork and collaborate in data analysis and modelling.
The coast of Namibia is one of three places on earth with persistent low-level clouds, and the only such location with a steady supply of tiny aerosol particles in the form of smoke from inland fires that mix with the clouds. NASA’s Observations of Aerosols Above Clouds and their Interactions (ORACLES) mission will observe and measure how these particles interact with clouds and change their ability to warm or cool the planet.
“This is the perfect natural laboratory to study aerosol-cloud interactions, which are some of the largest uncertainties in the prediction of future climate,” said Jens Redemann, ORACLES principal investigator at NASA’s Ames Research Center in Moffett Field, California, in a statement issued yesterday by the US Embassy in Windhoek.
It is not the first time that NASA has worked with Namibian scientists or institutions. The Gobabeb Research and Training Centre in the Namib Desert has previously worked with NASA using the desert as an analogue for the surface of other planets, providing ground-based remote sensing of the atmosphere.
“Human activities currently are estimated to be responsible for perhaps half of all the aerosol particles in the atmosphere,” said Robert Wood, a cloud scientist at the University of Washington in Seattle and ORACLES deputy principal investigator.
“Smoke particles both reflect sunlight back to space, thus cooling the earth, and absorb sunlight, which has the opposite effect of warming the earth. When aerosols encounter clouds, they also change the properties of the clouds they are ingested into.”
Changes in the properties of the cloud layer caused by aerosols could also have an effect on regional coastal fisheries by altering the amount of sunlight reaching the ocean surface that drives currents and ocean upwelling.
“Science is a great unifier,” said Bernadette Squire Luna, ORACLES project manager at Ames. “We are building relationships with Namibian scientists that will outlast this project and will lead to yet more science and more interactions. We’re connecting our countries in a very grass-roots way.”
The scientists also have two research aircraft that will be used in the study.
NASA’s P-3 aircraft, managed by the agency’s Wallops Flight Facility in Wallops Island, Virginia, carries five remote sensing instruments and flies through the cloud and aerosol layers at up to 20,000 feet to gather direct measurements from more than a dozen cloud and aerosol probes attached to the wings and inlets on the windows.
NASA’s ER-2 aircraft, managed by the agency’s Armstrong Flight Research Center in Edwards, California, will fly at 65,000 feet with instruments that make measurements similar to those acquired from satellites.
ORACLES flights will complement and validate current satellite observations of aerosols and clouds, and test instruments that may fly on future satellites by making detailed observations that are impossible to make from space with current capabilities.
ORACLES is a collaborative research effort that involves more than a hundred scientists from five NASA centers, two national laboratories, 10 U.S. universities, and five African research institutions. It’s a multi-year NASA Earth Venture suborbital investigation to probe earth system processes that are not completely understood. These flights from Namibia are the first of several planned field seasons for the mission. Earth Venture investigations are part of NASA’s Earth System Science Pathfinder program managed at the agency’s Langley Research Center in Hampton, Virginia.