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TES Summary. The primary focus of TES is to make unique, global measurements from space of tropospheric O 3 and its precursors for: Assessment of pollution flow on a global scale. Evaluation of chemical reactions that cleanse the atmosphere on a global scale.
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TES Summary • The primary focus of TES is to make unique, global measurements from space of tropospheric O3 and its precursors for: • Assessment of pollution flow on a global scale. • Evaluation of chemical reactions that cleanse the atmosphere on a global scale. • Evaluation of the coupling between climate change and atmospheric chemistry on a global scale. • The primary TES measurements are vertical profiles of: • O3, CO, H2O and Temperature (nadir) • HNO3, O3, Temperature (limb) • TES INTEX-B Planning: http://es.jpl.nasa.gov/INTEX_B_2006/Intex_B_2006.html
TES Validation Priorities for INTEX-B: • Ozone • Lidar profiles of ozone under different atmospheric conditions during long, level flight legs along Aura nadir orbit track • In situ profiles of ozone along the Aura nadir orbit track. • Carbon Monoxide • Similar to ozone, getting in situ profiles under a variety of atmospheric conditions along the Aura nadir orbit track • Nitric Acid (Measured in the Limb) • Profiles starting at the maximum altitude of the aircraft will provide useful validation information at the lowest altitudes for which TES can measure HNO3. • Measurements along the Aura nadir orbit track should be sufficient to validate nitric acid. A flight along the TES limb track would be a much lower priority.
TES Observation Modes • Global Survey: • Standard operating mode – nadir profiles only • Every other day • Maximum of 3408 profiles over ~26 hours (16 orbits) • Distance between profiles ~186 km • Special Observations: • Step & Stare • 125 nadir profiles • Covers ~50 latitude • Distance between profiles ~45 km • Limb Only: • 62 limb profiles • Only time TES makes limb measurements
TES Ozone Profile Validation • TES biases high relative to ozonesondes in the upper troposphere • Improvement seen with updated radiance calibration • TES able to distinguish high/low abundances in both lower and upper troposphere • TES can detect large scale features in ozone profiles
TES CO adjusted to MOPITT a priori and MOPITT CO smoothed by TES AK 850 hPa 500 hPa 150 hPa Column
Instrument OverviewBasic Instrument Characteristics • Fourier Transform Spectrometer • Wavelength Range: 5 to 15.4 µm • One spectral scan every 4 or 16 s • Four optically conjugated 1x16 pixel detector arrays • Spatial sampling of 5x8 km nadir and 2.3 km (vertical) at the limb • 2-axis gimbaled pointing mirror • Instrument Mass - 328 kg (722 lb)
Level 1A: Produces geolocated interferograms. Level 1B: Produces radiometrically and frequency calibrated spectra with NESR (noise equivalent spectral radiance). Level 2: Produces VMR and temperature profiles. Level 3: Produces global maps. TES Algorithm Overview
Instrument OverviewInstrument Characteristics • Mid-Infrared Fourier Transform Spectrometer (Interferometer) • Four detector arrays, each covering a different spectral range and each with a set of selectable filters • 1A, 1900-3050 cm-1 (3.27 -5.263 µm), 5 selectable filters • 1A1, 1900-2250 cm-1, for GS nadir and limb measurements. • 2A, 1100 - 1950 cm-1 (5.128 - 9.091 µm), 4 selectable filters • 2A1, 1100-1350 cm-1, for GS nadir measurements. 2A1 and 2A4, 1670-1975 cm-1 , for GS limb measurements. • 1B, 820 - 1150 cm-1 (8.696 - 12.200 µm), 2 selectable filters • 1B2, 925-1170 cm-1, for GS nadir measurements. 1B1, 800-1065 cm-1, and 1B2 for GS limb measurements. • 2B, 650 - 900 cm-1 (11.11 - 15.38 µm), 1 filter • 2B1, 650-900 cm-1, for GS nadir and limb measurements. • Detectors actively cooled to ~65 K with a pulse-tube cooler • Interferometer • Of the Connes design with back-to-back cube corners • Passively cooled to 180 K • Maximum optical path difference of 33 cm. Limb views use the entire maximum optical path difference. Nadir Scans use an 8.25 cm maximum optical difference.
