Optical depth, size distribution and flux of dust from Owens Lake, California

A joint United States/Russian/French collaborative experiment was undertake n in March 1993 and March 1996. Projects LODE I and II (Lake Owens Dust Exp eriments) took place on the anthropogenically desertified playa (dry lakebe d) and surrounding regions of Owens Lake, in east-central California. One o f the five parts of Project LODE was to determine relationships between opt ical depth and flux of dust emitted from the dry lake. Project LODE II incl uded subsequent dust plume measurements and size distributions obtained thr ough April 1996, to further refine the flux measurements for distinct miner al aerosol source regions at Owens Lake. Size distributions of dust aerosol were determined and aerosol optical dept hs were calculated from sunphotometer solar extinction measurements taken d ownwind in plumes coming from the emissive areas of Owens Lake. This source was visually observed for 10 measured dust storms. The plume mass was calc ulated to be 1.5 x 10(9) g using ground-based measurements and greater than or equal to 1.6 x 10(9) g from satellite data. Project LODE II results wer e found to be consistent with LODE I results for the south end of the playa , but flux values were found to be reduced for the northeastern portion of the playa by comparison. Vertical flux values estimated by sunphotometry we re found to be consistent with values estimated via a micrometeorological m ethod. Copyright (C) 1999 John Wiley & Sons, Ltd.