Dr. Christopher R. Webster (Group Leader), Stephanie
Blueford (Secretary)
Dr.
Lance E. Christensen,
Gregory J. Flesch, Dr. Robert L. Herman,
J. Jesse Landeros,
Dr. Ram Vasudev,
Aaron Milam, Kasey Truong, Dr. Chris Tarsitano, Katy Modarress, James E. Swanson, W. Stephen Woodward
JPL's Atmospheric Laser Spectroscopy Group seeks to understand the photochemistry,
dynamics, and evolution of Earth and planetary atmospheres through interpretation of in-situ
measurements of gas, particulate, and mineral composition using state-of-the-art
laser spectrometers built by the group. Over the last 20 years we have conceived,
designed, and built a variety of tunable diode laser (TDL) and Quantum-Cascade
(QC) laser spectrometers that have flown on balloon, aircraft, and spacecraft
platforms. Laboratory spectroscopy and instrument miniaturization programs
have produced high-sensitivity spectrometers weighing less than a kilogram.
For Earth studies of stratospheric chlorine and nitrogen photochemistry, and of
atmospheric transport, we have used tunable laser absorption to make atmospheric
measurements of numerous gases including balloon measurements of NO, NO2,
O3, H2O, CO2, CH4, N2O,
13CH4, HDO, HCl, HNO3; and aircraft measurements of HCl, NO2, N2O,
CH4, H2O, CO, 13CO2, and O3.
Studies of cirrus origin and atmospheric transport resulted from our recent
measurements of water isotopes HDO, H216O, H217O,
and H218O in and out of clouds. Field missions include: BLISS (balloon,
12 flights); ALIAS (ER-2-aircraft,
~350 flights); JPL-Laser Hygrometer (ER-2 aircraft,
~50 flights; DC-8 aircraft, 30
flights); ALIAS-II (balloon, 11 flights); ALIS
for isotopic CO2. These instruments have participated in 11 major field campaigns for
NASA (AASE-II, SPADE, ASHOE, STRAT, POLARIS, CAMEX-3, SOLVE, CAMEX-4,
CRYSTAL-FACE, Pre-AVE, AVE) from 1991 through
2004 out of
Texas, California, Maine, Alaska, Florida, Brazil, Hawaii, New Mexico, Fiji, New Zealand, Sweden,
and Costa Rica.
For planetary applications, we have developed spectrometers based on mid-IR
and near-IR TDLs, and room-temperature QC lasers: the PIRLS instrument for the
Cassini Titan Probe; the MIRLS instrument for
Mars photochemistry developed for lander and Mars Airplane applications.; two
near-IR laser spectrometers for Mars
H2O
and CO2 sent to Mars as part of the Mars 98
Surveyor's (MVACS) payload; and several under consideration as part of
Mars Scout and Mars Science Laboratory (MSL) instruments. In addition, we are developing
room-temperature mid-IR Quantum Cascade Laser Spectrometers
for Mars, Titan, Venus, and Europa, and are part of JPL's Grand
Challenge Project studying biogenic
gases and their isotopic ratios as signatures of extraterrestrial
life.
