HANDIX SCIENTIFIC INC — National Aeronautics and Space Administration SBIR Phase I: S1

Description

Aerosol extinction measurements are crucial to understanding the effects of atmospheric particles on ozone depletion (stratosphere), radiation (stratosphere and troposphere), visibility (troposphere) and public health (boundary layer).nbsp; Despite the acute need, no existing instrument can measure direct, in situ aerosol extinction profiles from the ground to the mid-stratosphere.nbsp; Satellite-based instruments, including NASArsquo;s new Stratospheric Aerosol and Gas Experiment III-ISS, report extinction globally but are currently validated by indirect measurements with ~40% uncertainty. nbsp;This uncertainty could be eliminated by measuring extinction directly with the balloon-borne Open-path Cavity Ringdown Spectrometer (BOPCRDS) we will develop in this project.nbsp; The BOPCRDS (expected precision is 0.05 Mm-1) will cost lt;$25,000, and its open-path configuration will enable it to measure ambient extinction (rather than extinction from dried particles or estimated from size distribution measurements) from 0-30 km altitude, thereby significantly advancing the current state-of-the-art.nbsp; During Phase I we will (1) design and build the BOPCRDS, (2) test it at -60 degrees Celsius and on a vibration table, (3) compare measurements against theory using gases with known extinction cross-sections, (4) deploy it during a SAGE III-ISS overpass and demonstrate its utility for satellite validation by comparing its measurements against the current state-of-the-art instruments. nbsp;In Phase II, we will develop a multi-wavelength, miniature BOPCRDS with expanded dynamic range and target price of $5,000.nbsp; Increased dynamic range could make the BOPCRDS useful for measuring stratospheric aerosol during volcanically active periods and tropospheric profiles in polluted regions.