9409222 Hara Research will be undertaken in response to a one-time Program Announcement (NSF 93-101) for the Coastal Ocean Processes (CoOP) Coastal Air-Sea Chemical Fluxes pilot study. The NSF/CoOP Study will augment and collaborate with the ONR-sponsored Marine Boundary Layer (MBL) Advanced Research Initiative (ARI) project scheduled for 1995 off the coast of Monterey, California. The overall scientific project is interdisciplinary, with the NSF/CoOP efforts addressing chemical and biological parameters, while the ONR study focuses on physical oceanographic and meteorological parameters. This is a collaborative project between investigators from the Woods Hole Oceanographic Institution and from Scripps Institution of Oceanography. The research will improve our understanding of air-sea gas transfer under different environmental conditions at the air-sea interface. A new in situ instrument will be developed to measure the gas transfer velocity (k) on time scales of minutes to hours that are much shorter than conventional tracer techniques (days or longer). The instrument will be integrated into a small research catamaran called LADAS which is towed behind a research vessel. LADAS carries a scanning laser slope gauge, to measure the three-dimensional capillary-gravity wave spectrum, meteorological instruments, and a long-wave monitoring capability. Additionally a surface microlayer sampler will be installed on the catamaran to enable coincident measurements of the gas transfer velocity, small scale roughness, wind stress, and surface chemical parameters. LADAS will be deployed in several field experiments to determine air-sea gas transfer rates under realistic ocean conditions and especially to relate these observations over different spatial and temporal scales in coastal environments. Such analyses will not only provide a more accurate parameterization of gas transfer velocity by avoiding biases caused by long time averaging, but will also provid e insights as to the transient nature of gas flux. The correlation of surface roughness and gas flux will benefit future global remote sensing of air-sea gas exchange since surface roughness is one of sea surface parameters than can be remotely measured from aircraft and satellites.