Remote Sensing

Remotely Sensed Ammonia Emission From Fumarolic Vents Associated With A Hydrothermally Active Fault In The Salton Sea Geothermal Field, California

Airborne hyperspectral imaging surveys were conducted over a geothermally active region straddling the southeastern shore of the Salton Sea in Southern California. The imagery was acquired across the 7.613.5 mm longwaveinfrared region with a ground sample distance of approximately 1 m. Prominent thermal hot spots associated with fumaroles along a known fault line were observed to coincide with emission of free ammonia, presumed to originate from geothermally induced pyrolytic decomposition of nitrogenous compounds that permeate the lake water, sediment, and adjacent agricultural terrain. It is shown that the inferred fluxes of ammonia constitute a significant fraction (1025%) of the total atmospheric ammonia burden assessed for the Salton Sea environs and represent a previously unreported source for that locale.