National Aeronautics and Space Administration Jet Propulsion Laboratory
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer TES Science Team Meeting – Feb 2009 TES Data User Session Susan Kulawik Ming Luo Greg Osterman TES Science Team Jet Propulsion Laboratory/California Institute of Technology
National Aeronautics and Space Administration Jet Propulsion Laboratory California Core Product. Institute of Technology Useful Range Level 1 B Radiances N/A Temperature 10 h. Pa to surface O 3 10 h. Pa to surface (nadir) 10 to 300 h. Pa (limb) CO 100 h. Pa to surface Tropospheric Emission Spectrometer TES Data Products Estimated Bias & Accuracy * Vertical Res. Validation papers On-orbit nadir comparisons with SHIS and AIRS: 290 -295 K range: Bias <0. 3 K and Std <0. 3 K. 265 -270 K range: Bias <0. 5 K, and Std ~0. 5 K bias <0. 6 K in lower trop, <0. 5 K in upper trop and stratosphere N/A Shephard et al. , 2007 1 km in lower trop; ~3 km at the tropopause (100 h. Pa); 3 km in limb Herman, Shephard, et al. , 2009 (in prep) 4 -6 km in nadir 13 -3 km in limb Worden et al. , 2007; Nassar et al. , 2008; Richards et al. , 2008; Osterman et al. , 2008 Boxe et al. , 2009 (in prep); Osterman et al. , 2009 (limb, in prep); 6 km in nadir Luo et al. , 2007 a, b; Lopez et al. , 2008; Ho et al. , 2009 (in prep) rms 1. 5 K in lower trop, 1 K in upper trop and stratosphere Nadir: 3 -10 ppb high bias for nadir in troposphere 7 -16 ppb upper limit rms with expected value for individual profile expected to be much smaller Limb: Low bias of 1015% in the lower strat High bias of 15 -35% in the upper strat 15 -30% rms in the strat 5 -10% global averaged low bias (15 -20% rms) compared to MOPITT. Slightly lower in mid-lat and slightly higher in tropics compared to insitu data with 10 -20% variability.
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer TES Data Products Core Product Useful Range Estimated Bias & Accuracy * Vertical Res. Validation papers H 2 O 200 h. Pa to surface Nadir: Lower troposphere (moist): 2 km in lower trop. ; ~4 km in the upper trop. (200 h. Pa); 3 km in limb Shephard et al. , 2008 6 km Worden et al. , 2006 8 -9 km Payne et al. , 2008, in review 0. 15 -0. 3 K low bias compared to AMSR-E (night) 0. 2 -0. 4 K low bias (day) 0. 5 -0. 8 K Std Dev for both night and day 30 -200 h. Pa depending on radiance noise, mean bias 50 h. Pa limited sensitivity at optical depths less than 0. 2 N/A Lampel, Kerola, in prep N/A Eldering et al. , 2008 10% high bias 30% rms 4 km M Coffey et al. , 2008 Bias: <5%, Std: , ~20 % Upper troposphere (dry) Bias: ~15%, Std: ~40% * HDO 200 h. Pa to surface CH 4 100 to 700 h. Pa; (peak sensitivity 200 -400 h. Pa) Sea Surface Temperature N/A Cloud Top Pres. N/A Cloud Eff. optical depth 20 to 900 h. Pa HNO 3 10 h. Pa to surface *Important to note that the TES statistics are NOT weighted by water vapor layer amounts HDO/H 2 O biased 5% high by 5% with a total expected error of 1. 5% 3 -4% high bias 1 -2% Std
National Aeronautics and Space Administration Jet Propulsion Laboratory California Core Product. Institute of Technology Useful Range Level 1 B Radiances N/A Temperature 10 h. Pa to surface O 3 CO Tropospheric Emission Spectrometer TES Data Products Estimated Bias & Accuracy * Vertical Res. Validation papers On-orbit nadir comparisons with SHIS and AIRS: 290 -295 K range: Bias <0. 3 K and Std <0. 3 K. 265 -270 K range: Bias <0. 5 K, and Std ~0. 5 K bias <0. 6 K in lower trop, <0. 5 K in upper trop and stratosphere N/A Shephard et al. , 2007 1 km in lower trop; ~3 km at the tropopause (100 h. Pa); 3 km in limb Herman, Shephard, et al. , 2009 (in prep) Research Products: rms 1. 5 K in lower trop, Ammonia 1 K in upper trop and stratosphere 10 h. Pa to. Methanol surface (nadir) Nadir: 4 -6 km in nadir 10 to 300 h. Pa (limb) 3 -10 ppb high bias for 13 -3 km in limb nadir in troposphere Carbon 7 -16 Dioxide ppb upper limit rms 100 h. Pa to surface with expected value for individual profile expected to be much smaller Limb: Low bias of 1015% in the lower strat High bias of 15 -35% in the upper strat 15 -30% rms in the strat 5 -10% global averaged low bias (15 -20% rms) compared to MOPITT. Slightly lower in mid-lat and slightly higher in tropics compared to insitu data with 10 -20% variability. 6 km in nadir Worden et al. , 2007; Nassar et al. , 2008; Richards et al. , 2008; Osterman et al. , 2008 Boxe et al. , 2009 (in prep); Osterman et al. , 2009 (limb, in prep); Luo et al. , 2007 a, b; Lopez et al. , 2008; Ho et al. , 2009 (in prep)
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Where to get TES Data/Documentation • The primary location for obtaining TES data is the Earth Observing System (EOS) Data Gateway https: //wist. echo. nasa. gov/api/. This site makes available earlier versions of the TES data. • A secondary location for obtaining TES data is the Langley ASDC data pool. The data pool has space limitations that make it somewhat dynamic, therefore older versions of TES data may not be available there. http: //eosweb. larc. nasa. gov/PRODOCS/tes/table_tes. html • Aura Data Validation Center – (Subsetting, validation data) http: //avdc. gsfc. nasa. gov/ • Documentation available at the Langley ASDC site and the TES website: http: //tes. jpl. nasa. gov/
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Documentation & Readers • TES Quick Start Guide – In development • TES Data User’s Guide v 4. 0 – Completed will be available within a couple of weeks on the TES web sites • TES L 2 Data Product Specification v 11. 8 – Provides information on all TES Level 2 data fields • TES L 2 Validation Report v 4. 0 – Nearly complete (available in April 2009) • L 2 Data Readers (in IDL) available at the Langley ASDC • Ozone “C-Curve” flag routines (IDL) available at ASDC soon
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer TES Nadir Observations TES Footprint 5 x 8 km Global Survey footprints 180 km apart Every 2 days… ~703 and counting Step & Stare footprints 45 km apart Special observation ~1747 run as Feb 2009 Transect footprints 12 km apart Special observation ~192 run as of Feb 2009
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Stare 32 scans at same target Special observation ~65 run as of 2/2009 Tropospheric Emission Spectrometer TES Special Observations Step & Stare footprints 45 km apart Special observation ~1747 run as Feb 2009
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Elevated CO and O 3 over SE Texas observed from TES on Aug 23, 2006 Step & Stare footprints 45 km apart Special observation ~1747 run as Feb 2009
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Using Satellite Data to Study Air Pollution and Potential Health Impacts - Continued Aura Contribution: Using OMI/MLS products to map tropospheric ozone along with the ability of TES to provide vertical information on ozone and carbon monoxide in the troposphere to help the EPA to understand air pollution events Transect footprints 12 km apart Special observation ~192 run as of Feb 2009 TES Contribution: TES provided special observations across the US/Mexico border near San Diego and El Paso Future Work: The work in this project is a first step and provides insight into how the NASA satellite data might be used with EPA tools and health data for studying air pollution events and their health impacts TES special observation near San Diego on June 9, 2007 showing high levels of ozone in the lower troposphere on the US side of the border 10
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer TES Stare Observations • Stare observations used mostly for validation (ARC-IONS, other ozonesonde sites) Stare 32 scans at same target Special observation ~65 run as of 2/2009
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Scans Start Date/ First Run ID Tropospheric Emission Spectrometer Global Survey Changes Sequences August 22, 2004 / First GS Run ID 2026 (First 4 GS runs were 4 orbits only) 3 Limb/ 2 Nadir 1152 sequences (72 per orbit) (First full GS is Run ID 2147/Sep 20, 2004) May 21, 2005 / Run ID 2931 January 10, 2006 / Run ID 3239. 3 Nadir 1152 sequences (72 per orbit) 1136 sequences (71 per orbit) June 6, 2008 / Run ID 7370. 3 Nadir 960 sequences (60 per orbit) July 30, 2008 / Run ID 8187. 3 Nadir 768 sequences (48 per orbit) May 27, 2008 AGU Joint Assembly Maximum Number of TES L 2 Profiles Along-Track Distance between Successive Nadir Scan Locations Maximum of 4608 L 2 profiles (1152 sequences x (3 Limb Scans+ 1 Nadir Scan)) Maximum of 3456 L 2 profiles (1152 sequences x 3 nadir scans) Maximum of 3408 L 2 profiles (1136 sequences x 3 nadir scans) Maximum of 2880 L 2 profiles ~544 km ~182 km No measurements (960 sequences x 3 nadir poleward of 60°S latitude. scans) Maximum of 2304 L 2 ~182 km profiles No measurements (768 sequences x 3 nadir poleward of 50°S, 70°N scans) latitude. 12
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Visualization of TES Special Observations http: //tes. jpl. nasa. gov/visualization/l 2 plots/ May 27, 2008 AGU Joint Assembly 13
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology May 27, 2008 Tropospheric Emission Spectrometer Special Observation Visualizations 2008 AGU Joint Assembly 14
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Run ID Table http: //tes. jpl. nasa. gov/datacalendar/
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Visualization of GS, Time Trends
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology • Tropospheric Emission Spectrometer TES Level 2 Data Version 3 The Version 3 TES data includes: – – – Limb profiles valid into the upper troposphere Improvements to the temperature retrievals (updated CO 2 spectroscopy) Improvements to the methane retrievals Species dependent quality control information Use of GMAO GEOS-5. 1. 0 products in L 2 retrievals – O 3, CO, H 2 O, HDO, TATM , SST validated with known biases – CH 4, Limb Products provisionally validated – F 04_04 in filename • TES Version 3 data products began processing January 2007 – Complete reprocessing completed (Sep 2004 – Sep 2008) • TES data and documentation can be found: – – Langley Atmospheric Science Data Center (http: //eosweb. larc. nasa. gov/) Aura Validation Data Center (http: //avdc. gsfc. nasa. gov/) TES L 2 Data User’s Guide available at both sites TES L 2 Validation Report available at both sites
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer TES Level 2 Data Version 4 • The Version 4 TES data will include: – Limb profiles valid into the upper troposphere – Improvements to the temperature retrievals (updated CO 2 spectroscopy) – Improvements to the methane retrievals – Species dependent quality control information – Use of GMAO GEOS-5 products in L 2 retrievals • Validation analyses are underway
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology • Version 4 Processing Began processing in September 2008 – – – – • Tropospheric Emission Spectrometer Labels in filename F 05_05 and F 05_06 Difference in label depends on the GMAO GEOS version used in the retrievals Special Observations before October 3, 2008 (Run ID 9168) use GMAO GEOS-5. 1. 0 Special Observations after October 3, 2008 (Run ID 9168) use GMAO GEOS-5. 1. 0 Global Surveys before September 30, 2008 (Run ID 9131) use GMAO GEOS-5. 1. 0 Global Surveys after September 30, 2008 (Run ID 9131) use GMAO GEOS-5. 1. 0 Problem found in some ozone retrievals at high surface pressures (>1030 h. Pa) and in the reporting of some water error matrices Restart V 04 processing in March 2009 with updated L 2 retrieval code – – Label in filename will be F 05_07 Differentiate GEOS-5. x. 0 version by date/run ID Processing should be complete late in 2009 Data with label F 05_05/F 05_06 remain publicly available until F 05_07 is processed for a given run ID – usable in scientific analyses
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer TES Level 2 Data Version 4: Validation Update • The Version 4 TES data has undergone preliminary validation analyses (processing began in early Sep 2008) • Improvements to nadir temperature key feature of V 04 data – Bias improved to less than 0. 5 K compared to sondes at nearly all altitudes – Bias at 400 h. Pa is ~0. 7 K – See R Herman et al. poster presentation on Wednesday • TES nadir methane retrievals processed as “representative tropospheric VMR” are biased 3 -4% high relative to aircraft data – See V Payne et al. , presentation – Wed 4: 45 • Minor changes to ozone retrievals – – High bias of 3 -10 ppbv (sondes) in V 02 data V 02, V 03 and V 04 data consistent More successful quality retrievals in V 04 Fewer cases with anomalous high ozone at surface in V 04 • V 04 carbon monoxide, nadir water, HDO, limb products consistent with V 03
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Tropospheric Emission Spectrometer Recommendations when using TES ozone data • V 02 data is a thoroughly validated version of the TES nadir ozone product • V 03 data is largely consistent with V 02 (as suggested by lidar and total column comparisons) – Some spatial differences (observed in monthly maps). – Differences in the occurrence of high surface/very low mid troposphere ozone cases (referred to as “C-curve” cases) observed in comparisons to ozonesondes • V 04 data validation is currently ongoing, early results suggest: – Higher number of good ozone profiles compared to V 03 – A decrease of more than 50% in C-curve cases compared to V 03 – There will be a full sonde validation analysis for V 04 data and could be expanded to include the TES limb ozone product
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology • • • Recommendations when using TES ozone data C-curve ozone profiles in TES data occur in ~5% of the V 03 ozone retrievals C-curve profiles tend to be a problem in the following cases: – – • Tropospheric Emission Spectrometer Tropical observations Locations very close to land/sea boundaries Mountainous terrain Desert terrain In these observing locations, the data user should use both the ozone master quality flag and test for C-curve cases The V 03 TES ozone master quality flag does not include a condition for Ccurve cases. – No C-curve flag in the V 03 data product – Pseudo-code for a C-Curve flag is available in the TES L 2 Data User’s Guide • The V 04 TES ozone master quality flag also does not include a condition for C-curve cases – There is a C-curve flag included in the data product based on the pseudo-code described in the Data User’s Guide.
National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology • Tropospheric Emission Spectrometer Recommendations when using TES ozone data Lin Zhang at Harvard University has developed an alternate test for C-curve profile in the TES ozone product – Preliminary tests with V 03 data show it to be very effective at screening out potentially anomalous high surface ozone values – Pseudo-code for this version of the flag will be included in the Data User’s Guide • TES ozone profiles flagged as C-curve cases are likely anomalous, but not necessarily always that way. – The flag could screen out actual cases of high ozone in the lowest portion of the troposphere.
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