NASA to use Walvis Bay for climate change investigations

WINDHOEK: Local climate scientists will work with the United States (US) space agency NASA on a five-year campaign in Namibia to investigate how air pollution, man-made fires across Africa, and warming oceans may affect the climate.

Project leader, Dr Jens Redemann of the National Aeronautics and Space Administration (NASA) Ames Research Centre in Mountain View, California, told Nampa via email on Wednesday that a NASA aircraft, including a Wallops P-3 aircraft and an Armstrong ER-2 aircraft, will be used to conduct the investigation and will be flying out of the Walvis Bay operation’s base.

“We are currently planning an initial site visit to Namibian airports, universities and research stations between 23 February and 05 March 2015. We are trying to gauge the interest of local scientists and research outfits to see if our project can mutually benefit all interests,” he noted.

He said two new Aerosol Robotic Network (Aeronet) ground-sites will be established in St. Helena – a tropical island of volcanic origin in the South Atlantic Ocean – and Angola, respectively.

The project includes airborne and ground-based observations of radiation, aerosol and cloud microphysics above and below aerosol and clouds over the south-east Atlantic Ocean. Three campaigns with P-3 aircraft are slated for September 2016, August 2017 and October 2018, respectively.

Southern Africa produces almost a third of the earth’s biomass burning (BB) aerosol particles, yet the fate of these particles and their influence on regional and global climate is poorly understood.

Observation of Aerosols above clouds and their interactions (Oracles) is a five-year investigation with three Intensive Observation Periods (IOP) designed to study key processes that determine the climate impacts of African BB aerosols. Particles lofted into the mid-troposphere are transported westward over the south-east Atlantic, home to one of the three permanent subtropical Stratocumulus (Sc) cloud decks in the world.

Redemann emphasised that the proposed Oracles study area in the south-east Atlantic is a prime location to study aerosol-cloud interactions, because it hosts some of the largest aerosol optical depths (AOD) on the planet. Inter-model differences in aerosol and cloud distributions, as well as their combined climatic effects in the south-eastern Atlantic are partly due to the persistence of aerosols above clouds (AAC).

“The varying separation of cloud and aerosol layers to be sampled during Oracles allow for a process-oriented understanding of how variations in radioactive heating profiles impact cloud properties, which is expected to improve simulations for other remote regions experiencing long-range aerosol transport above clouds,” he added.

The campaign forms part of five projects under the umbrella of the agency’s Earth Venture initiative. Each project is funded at a cost of US dollars 30 million (about N.dollars 300 million) over five years.

The other four selected Earth Venture investigations are: Atmospheric chemistry and air pollution; ecosystem changes in a warming ocean; greenhouse gas sources; and melting Greenland glaciers.