ORACLES and LASIC: New observational campaigns to improve understanding of the effects of Southern African Biomass Burning Aerosol on Radiation, Clouds and Climate.
Abstract
Southern Africa produces almost a third of the Earth's biomass burning (BB) aerosol particles. 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. The stratocumulus "climate radiators" are critical to the regional and global climate system. They interact with dense layers of BB aerosols that initially overlay the cloud deck, but later subside and are mixed into the clouds. These interactions include adjustments to aerosol-induced solar heating and microphysical effects, and their global representation in climate models remains one of the largest uncertainties in estimates of future climate. Hence, new observations over the SE Atlantic have significant implications for global climate change scenarios. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a five-year investigation between 2015 and 2019 with three Intensive Observation Periods (IOP), recently funded by the NASA Earth-Venture Suborbital Program. ORACLES is designed to improve understanding of aerosol-radiation-cloud-climate interactions in the SE Atlantic. These interactions will be studied using aircraft observations from the NASA P-3 and ER-2 aircraft, which will provide key aerosol and cloud property information to improve process and large-scale models. LASIC (Layered Atlantic Smoke Interactions with Clouds) is a DOE deployment of the ARM Mobile Facility to Ascension Island (June 2016 - October 2017) that will provide ground-based in situ and remote sensing observations of aerosols and clouds from Ascension Island (8S, 14W). BB aerosols from Africa frequently advect to Ascension Island where they mix down into the trade wind boundary layer and interact with clouds. This presentation will describe "first-light" observations from the 2016 ORACLES and LASIC deployments, focusing upon the absorptive and cloud nucleating properties of aerosols, their vertical distribution relative to clouds, the degree of aerosol mixing into clouds, and insights into processes that govern cloud property adjustments over the South-East Atlantic.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.A33L..01W
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3305 Climate change and variability;
- ATMOSPHERIC PROCESSESDE: 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSESDE: 3360 Remote sensing;
- ATMOSPHERIC PROCESSES