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Landsat Data Gap Study Activities Remote Sensing Technologies Project http: //calval. cr. usgs. gov/ Landsat Data Gap Study Activities Remote Sensing Technologies Project http: //calval. cr. usgs. gov/ Greg Stensaas, USGS Gyanesh Chander, Jon B. Christopherson SAIC Date: April 11, 2007 U. S. Department of the Interior U. S. Geological Survey

Medium Resolution Satellite Characterization l USGS mission to assess and understand remote sensing data Medium Resolution Satellite Characterization l USGS mission to assess and understand remote sensing data u and its application to science societal benefits u l Landsat Data Gap USGS providing technical and operational assessment u USGS will provide an operational program u USGS and NASA DCWG “Data Characterization Working Group” l Using JACIE and Landsat characterization methodology u 2

System/Product Characterization l l System Characterization is related to understanding the sensor system, how System/Product Characterization l l System Characterization is related to understanding the sensor system, how it produces data, and the quality of the produced data Imagery and data attempt to accurately report the conditions of the Earth's surface at a given the time. u Assessed by product characterization categories: l l l Geometric/Geodetic: The positional accuracy with which the image represents the surface (pixel coordinates vs. known ground points) Spatial: The accuracy with which each pixel represents the image within its precise portion of the surface and no other portion Spectral: The wavelengths of light measured in each spectral "band" of the image Radiometric: The accuracy of the spectral data in representing the actual reflectance from the surface Dataset Usability: The image data and understanding of the data is easily usable for science application 3

Joint Agency Commercial Imagery Evaluation (JACIE) Team l JACIE team formed in 2000 – Joint Agency Commercial Imagery Evaluation (JACIE) Team l JACIE team formed in 2000 – USGS lead u National Aeronautics and Space Administration (NASA), National Geospatial Intelligence Agency (NGA), U. S. Department of Agriculture (USDA), and U. S. Geological Survey (USGS) l 6 th Annual Workshop - March 2007 – Fairfax, VA l Enhanced scope to include high & medium resolution sensors useful to the remote sensing community u U. S. and International Systems – Satellite and Aerial u Multiple sensor types and resolutions u Understand characterize new sensors l Provide imagery users with an independent assessment with respect to product quality and usability l Support understanding of new remote sensing data applications l Provides government/industry communication/cooperation model 4

Background l l l The Earth observation community is facing a probable gap in Background l l l The Earth observation community is facing a probable gap in Landsat data continuity before LDCM data arrive in ~2011 A data gap will interrupt a 34+ yr time series of land observations Landsat data are used extensively by a broad & diverse users u u u l Landsat 5 limited lifetime/coverage Degraded Landsat 7 operations Either or both satellites could fail at any time: both beyond design life Urgently need strategy to reduce the impact of a Landsat data gap u u Landsat Program Management must determine utility of alternate data sources to lessen the impact of the gap & feasibility of acquiring data from those sources in the event of a gap A Landsat Data Gap Study Team, chaired by NASA and the USGS, has been formed to analyze potential solutions 5

Data Gap Study Team Management l l l Landsat Data Gap Study Team (LDGST) Data Gap Study Team Management l l l Landsat Data Gap Study Team (LDGST) u Developing a strategy for providing data to National Satellite Land Remote Sensing Data Archive for 1 -4 years LDGST Technical and Policy sub-groups u Developing & analyzing a set of technical & operational scenarios for receiving, ingesting, archiving, and distributing data from alternative, Landsat-like satellite systems. u Conduct trade studies & assess the risk of the various scenarios & provide rough order magnitude costs for the alternatives u Develop Data Gap program recommendation to OSTP u USGS to develop operational program for Data Gap and LDCM Data Characterization Working Group (DCWG) u Technical group from three field centers (USGS EROS, NASA GSFC, NASA SSC) to evaluated data from IRS-P 6 and CBERS -2 sensors 6

LDGST Membership Edward Grigsby, NASA HQ, Co- Chair Ray Byrnes, USGS HQ, Co- Chair LDGST Membership Edward Grigsby, NASA HQ, Co- Chair Ray Byrnes, USGS HQ, Co- Chair Garik Gutman, NASA HQ, Co- Chair Jim Irons, NASA GSFC, Community Needs Working Group Lead Bruce Quirk, USGS EDC, System Capabilities Working Group Lead Bill Stoney, Mitretek Systems, Needs-to-Capabilities Working Group Lead Vicki Zanoni, NASA HQ Detail, Team Coordinator and Synthesis Working Group Lead Mike Abrams, JPL Bruce Davis, DHS (NASA detailee) Brad Doorn, USDA FAS Fernando Echavarria, Dept. of State Stuart Frye, Mitretek Systems Mike Goldberg, Mitretek Systems Sam Goward, U. of Maryland Ted Hammer, NASA HQ Chris Justice, U. of Maryland Jim Lacasse, USGS EDC Martha Maiden, NASA HQ Dan Mandl, NASA GSFC Jeff Masek, NASA GSFC Gran Paules, NASA HQ John Pereira, NOAA/NESDIS Ed Sheffner, NASA HQ Tom Stanley, NASA SSC Woody Turner, NASA HQ Sandra Webster, NGA Diane Wickland, NASA HQ Darrel Williams, NASA GSFC 7

DCWG Team Membership NASA Stennis - Tom Stanley * - Mary Pagnutti (SSAI) * DCWG Team Membership NASA Stennis - Tom Stanley * - Mary Pagnutti (SSAI) * - Robert Ryan (SSAI) - Ross Kenton (SSAI) - Kara Holekamp (SSAI) NASA GSFC - Jim Irons ** - Brian Markham * - John Barker - Ed Kaita (SSAI) * - Raviv Levy (SSAI) - Julia Barsi (SSAI) - Jen Sun (SSAI) ** DCWG Chair * Co-chairs USGS EROS - Greg Stensaas * - Jon Christopherson (SAIC) * - Gyanesh Chander (SAIC) - Jim Storey (SAIC) - Mike Choate (SAIC) - Pat Scaramuzza (SAIC) Univ of Md Dept of Geography - Sam Goward Univ of Arizona - Kurt Thome SDSU - Dennis Helder - Dave Aaron USDA (FAS) - Bob Tetrault 8

Footprint Comparison Landsat ALI Resource. Sat LISS III ALOS ASTER/SPOT Resource. Sat AWi. FS Footprint Comparison Landsat ALI Resource. Sat LISS III ALOS ASTER/SPOT Resource. Sat AWi. FS CBERS MUXCAM CBERS IRMSS Rapid. Eye CBERS-3, 4 WFI-2 DMC 9 Note: For purposes of scene size comparison only. Locations do not represent actual orbital paths or operational acquisitions.

Requirements and Capabilities Analysis l Minimum acceptable specifications were derived to support basic global Requirements and Capabilities Analysis l Minimum acceptable specifications were derived to support basic global change research given available sources of Landsat-like data u 2 x Annual Global Coverage u Spatial Resolution Systems Considered üIRS Resource. Sat – 1, 2 (India) u Spectral Coverage üCBERS – 2, 2 A, 3, 4 (China & Brazil) u Data Quality üRapid Eye – 1, 2, 3, 4, 5 (Germany) üDMC (Algeria, Nigeria, UK, China) üTerra/ASTER (US & Japan) üHigh-resolution U. S. commercial systems üIKONOS, Quickbird, Orb. View-3 üALOS (Japan) üSPOT – 4, 5 (France) üEO-1/ALI (US) 10

Narrowed to 2: Resource. Sat and CBERS l India’s Resource. Sat-1 u u High Narrowed to 2: Resource. Sat and CBERS l India’s Resource. Sat-1 u u High Resolution Linear Imaging Self. Scanner (LISS-IV) – 5. 8 m - RGB u Medium Resolution Linear Imaging Self. Scanner (LISS-III) - 23 m - VNIR SWIR u Advanced Wide Field Sensor (AWi. FS) 56 m – VNIR SWIR u l Launched October 2003 Follow-on planned China-Brazil’s CBERS-2 u Launched October 2003 u HRCCD (High Resolution CCD Camera) VNIR u IRMSS (Infrared Multispectral Scanner) SWIR u WFI (Wide-Field Imager) - VNIR u Follow-on planned 11

Relative Spectral Response (RSR) Profiles Relative Spectral Response (RSR) Profiles

NASA/USGS LDSGT technical group with Dr. Navalgund, the director of ISRO SAC, Ahmedabad, India NASA/USGS LDSGT technical group with Dr. Navalgund, the director of ISRO SAC, Ahmedabad, India NASA/USGS LDSGT technical group at IRSO HQ in Bangalore, India June 10 -20, 2006

NASA/USGS technical group with Dr. Camara, the director of INPE, Brazil USGS Deputy Director NASA/USGS technical group with Dr. Camara, the director of INPE, Brazil USGS Deputy Director and NASA Program Executive with INPE Director 14 Oct 23 -26, 2006

Technical Report Sections • Background and Sensor overview • Data Characterization • Science Utility Technical Report Sections • Background and Sensor overview • Data Characterization • Science Utility • Mission Assessment • Many Appendixes Section 4 Science Utility 4. 1 Land Cover Trends Project 4. 2 Emergency Response Burn Mapping and MTBS Projects 4. 3 FEWS International Crop Monitoring Project 4. 4 Forest and Rangeland Project 4. 5 AWi. FS and Landsat Inter-Comparison Project 4. 6 Viability of IRS-P 6 Datasets for NLCD Products 4. 7 Global Agriculture Monitoring project (GLAM) Project 4. 8 Cropland Acreage Estimation and Mapping with USDA/NASS 4. 9 Use of AWi. FS data for Global Crop Production Assessments 4. 10 Use of AWi. FS Imagery for Wildfire Mapping in the USDA Forest Service 15

Technical report completed - 90 question Comparison of Resource. Sat, CBERS, and Landsat 16 Technical report completed - 90 question Comparison of Resource. Sat, CBERS, and Landsat 16

CBERS Downlink at EROS 17 CBERS Downlink at EROS 17

L 5 TM and CBERS-2 CCD Image Pairs Gobi (Dunhuang) desert test site Data L 5 TM and CBERS-2 CCD Image Pairs Gobi (Dunhuang) desert test site Data acquired on Aug 25, 2004 (20 min apart) L 5 TM WRS Path = 137 Row = 032 Nadir looking L 5 TM WRS Path = 219 Row = 076 Nadir looking Acquisition Date: Dec 29, 2004 CBERS-2 CCD Path = 154 Row = 126 Acquisition Date: Dec 30, 2004 CBERS-2 CCD Path = 23 Row = 55 sidelooking (off-nadir-look-angle=-6. 0333) L 5 TM WRS Path = 217 Row = 076 Nadir looking Acquisition Date: Nov 16, 2005 CBERS-2 CCD Path = 151 Row = 126 Acquisition Date: Nov 16, 2005

CBERS Status and Plans l CBERS-2 u Data has suffered anomalies no longer available CBERS Status and Plans l CBERS-2 u Data has suffered anomalies no longer available l CBERS-2 B to be launched in late 2007 u Test Downlinks u Calibration cooperation u And more? 19

L 7 ETM+ and IRS-P 6 Image Pairs 740 km All scenes collected June L 7 ETM+ and IRS-P 6 Image Pairs 740 km All scenes collected June 19 th, ’ 05 Centered over Mesa/Phoenix, AZ 141 x 141 km 181 x 185 km Swath Widths AWi. FS: 740 km Landsat: 181 km LISS-III: 141 km

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AWi. FS Extensively Evaluated l By DCWG Partners: EROS, NASA SSC, NASA GSFC u AWi. FS Extensively Evaluated l By DCWG Partners: EROS, NASA SSC, NASA GSFC u l By USDA NAS and FAS u u l Application focused USGS EROS evaluating applications also AWi. FS Weaknesses u l Technical characterization Less resolution; No Band 1 or Band 7 AWi. FS Strengths u u Broad Coverage and Rapid Repeat (5 days!) Radiometric Resolution (10 bits) Cost & Timeliness Generally High Quality 22

AWi. FS/Resource. Sat Plans l Further testing u l Archiving USDA AWi. FS purchases AWi. FS/Resource. Sat Plans l Further testing u l Archiving USDA AWi. FS purchases u l In discussion now Further analysis as Landsat Data Gap source u u u l Especially Applications Test Downlinks RFI evaluations Data Gap planning Indian Remote Sensing is moving ahead u u Resource. Sat-2 to launch in 2008 Resource. Sat-3 in planning for 2013 timeframe 23

Many New Sources are Coming l 17 countries have mid to hi res. satellites Many New Sources are Coming l 17 countries have mid to hi res. satellites in orbit u Should be 24 countries by end of decade Optical: 31 in orbit, 27 planned Radar: 4 in orbit, 9 planned (all foreign) l In-Orbit or currently planned resolutions: l l Very High Hi-Medium Low-Medium (0. 4 m-1 m) 13 (1. 8 m-2. 5 m) 9 (4 m-8 m) 14 (10 m-20 m) 10 (30 m-56 m) 7 24

CEOS Calibration-Validation Sites l World-wide Cal/Val Sites for African Desert Sites u u u CEOS Calibration-Validation Sites l World-wide Cal/Val Sites for African Desert Sites u u u l l Monitoring various sensors Cross calibration Integrated science applications Site description Surface Measurements FTP access via Cal/Val portals Prime Sites for data collection Supports GEO Tasks ALOS Cal/Val sites 25 Landsat Super sites

USGS System Characterization l l l Satellite Characterization and Calibration u US system calibration USGS System Characterization l l l Satellite Characterization and Calibration u US system calibration and characterization group u Part of Joint Agency Commercial Imagery Evaluation (JACIE) Team u Working on Landsat Data Gap Assessment Aerial Mapping Sensor Characterization and Calibration u Film Camera Calibration – Optical Science Lab u Digital Aerial System and Product Characterization u Digital Camera Calibration - Medium Format Camera Calibration Lab u In situ Calibration/Characterization for both analog and digital sensors u USGS Quality Assurance Plan for Digital Aerial Imagery Satellite and Aerial System characterization and calibration sites u In situ range specifications and range development u Ground Instrumentation supporting product validation • http: //calval. cr. usgs. gov/ 26

Questions? l Looking at other systems u l 5 Posters available u u u Questions? l Looking at other systems u l 5 Posters available u u u l DMC Surrey. Sat report completed Landsat Data Gap JACIE Commitment to Commercial Remote Sensing Question of Scale Geometric Calibration of Medium Format Digital Cameras What About Digital Imagery OSL tour if interested 27

Backup Slides 28 Backup Slides 28

Team Strategy Objective l Recommend options, using existing and near-term capabilities, to store, maintain, Team Strategy Objective l Recommend options, using existing and near-term capabilities, to store, maintain, and upgrade science-quality data in the National Satellite Land Remote Sensing Data Archive u Consistent with the Land Remote Sensing Policy Act of 1992 Approach l Identify data “sufficiently consistent in terms of acquisition geometry, spatial resolution, calibration, coverage characteristics, and spatial characteristics with previous Landsat data…” u Consistent with Management Plan for the Landsat Program Process l l Identify acceptable gap-mitigation specifications Identify existing and near-term capabilities Compare capabilities to acceptable specifications Synthesize findings and make recommendations 29

CBERS- Sensor Compliment l CBERS satellite carries on-board a multi sensor payload with different CBERS- Sensor Compliment l CBERS satellite carries on-board a multi sensor payload with different spatial resolutions & collection frequencies u u u l l HRCCD (High Resolution CCD Camera) - VNIR IRMSS (Infrared Multispectral Scanner) - SWIR WFI (Wide-Field Imager) - VNIR The CCD & the WFI camera operate in the VNIR regions, while the IRMSS operates in SWIR and thermal region In addition to the imaging payload, the satellite carries a Data Collection System (DCS) and Space Environment Monitor (SEM) 30

China Brazil Earth Resources Satellite CBERS l CBERS-1, was launched on Oct. 14, 1999 China Brazil Earth Resources Satellite CBERS l CBERS-1, was launched on Oct. 14, 1999 u u u l CBERS-2 (or ZY-1 B) was launched successfully on Oct. 21, 2003 from the Taiyuan Satellite Launch Center u l The spacecraft was operational for almost 4 years The CBERS-1 images were not used by user community On Aug. 13, 2003, CBERS-1 experienced an X-band malfunction causing an end of all image data transmissions The spacecraft carries the identical payload as CBERS-1 CBERS Orbit u u u u Sun synchronous Height: 778 km Inclination: 98. 48 degrees Period: 100. 26 min Equator crossing time: 10: 30 AM Revisit: 26 days Distance between adjacent tracks: 107 km 31

China-Brazil Earth Resources Satellite (CBERS 1 -2) l l l l l CBERS-1 launched China-Brazil Earth Resources Satellite (CBERS 1 -2) l l l l l CBERS-1 launched on October 14, 1999; CBERS-2 on October 21, 2003; CBERS 2 B to be launched in 2006 Revisit time is 26 days Orbital altitude/inclination: 778 km/98. 5 degrees Nodal crossing: 10: 30 a. m. System life: 2 years Data only downlinked to Brazil and China, may commercialize in future Each satellite has 3 cameras (see below) Availability of data and products, data policy, and pricing is TBD Website: http: //www. cbers. inpe. br/en/ 32

The USGS Center for EROS Director, R. J. Thompson, visiting with Jose Bacellar from The USGS Center for EROS Director, R. J. Thompson, visiting with Jose Bacellar from Brazilian National Institute for Space Research (INPE) after a successful China-Brazil Earth Resources Satellite (CBERS-2) data downlink l “CBERS in a box” works - The CBERS-2 capture and processing system is a small computer that can perform the following tasks l ingest the raw data l show the image data in a “moving window” display l record the raw data in the computer’s hard disk l process the raw data to level 1 products l generate quick looks to populate the Data Catalog of the system l make the level 1 data available to the users

The first China-Brazil Earth Resources Satellite (CBERS-2) data downlink at USGS Center for EROS The first China-Brazil Earth Resources Satellite (CBERS-2) data downlink at USGS Center for EROS in support of the Landsat Data Gap Study

Challenges and Future Plans l l l CBERS-2 High Density Data Recorder (HDDR) is Challenges and Future Plans l l l CBERS-2 High Density Data Recorder (HDDR) is not in use due to power limitations The IRMSS stopped working in Apr 2005 due to power supply failure Limited coincident Landsat/CBERS image-pairs u u u l l l CBERS-2 B test downlink at USGS EROS Analyze IRMSS data Evaluate the raw data (artifacts, noises) u u u l Evaluate the relative calibration of the CCD data Evaluate Bias estimates Night time acquisitions Perform similar cross-calibration experiment u u l Limited data distribution policies outside the country Limited documentation available No L 7 data downlink in Brazil Data processed from INPE and CRESDA Temporal scale (image pairs from 2003 -2005) Perform joint field Vicarious calibration campaign 35

Resource. Sat-1 Overview l RESOURCESAT-1 carries three sensors u u u l l High Resource. Sat-1 Overview l RESOURCESAT-1 carries three sensors u u u l l High Resolution Linear Imaging Self-Scanner (LISS-IV) Medium Resolution Linear Imaging Self-Scanner (LISS-III) Advanced Wide Field Sensor (AWi. FS) All three cameras are “push broom” scanners using linear arrays of CCDs RESOURCESAT-1 also carries an On-board Solid State Recorder (OBSSR) with a capacity of 120 Giga-Bits to store the images 36

Resourcesat-1 (IRS P 6) l l The RESOURCSAT-1 satellite was launched in to the Resourcesat-1 (IRS P 6) l l The RESOURCSAT-1 satellite was launched in to the polar sun-synchronous orbit (altitude of 817 km) by PSLV-C 5 launch vehicle on October 17, 2003 with a design life of 5 years RESOURCSAT-1 is also called IRS-P 6 u Most advanced Remote Sensing Satellite built by ISRO u Tenth satellite of ISRO in IRS series u Other ISRO operational satellites are IRS 1 -C, IRS 1 -D, IRS P-2, IRS P-3 37

Advanced Wide Field Sensor (AWi. FS) l l The AWi. FS with twin cameras Advanced Wide Field Sensor (AWi. FS) l l The AWi. FS with twin cameras is a moderate-resolution sensor offering a GSD of 56 m at nadir Quantization: 10 bits Combined ground swath is 740 km with five day repeat cycle Operates in four spectral bands – three VNIR one SWIR VITAL FACTS: • • Instrument: Pushbroom Bands (4): 0. 52 -0. 59, 0. 62 -0. 68, 0. 77 -0. 86, 1. 55 -1. 70 µm Spatial Resolution: 56 m (near nadir), 70 m (near edge) Radiometric Resolution: 10 bit Swath: 740 km Repeat Time: 5 days Design Life: 5 years 38

Resource. Sat-1 (IRS-P 6) l l l Resource. Sat-1 was launched on October 17, Resource. Sat-1 (IRS-P 6) l l l Resource. Sat-1 was launched on October 17, 2003 by Indian Remote Sensing (IRS) Orbital altitude/inclination: 817 km/98. 69 degrees Nodal crossing: 10: 30 a. m. System life: 5 years Three instruments devoted to land imaging u u u l Space Imaging has distribution rights outside of India u l Linear Imaging Self-Scanner (LISS-IV) Linear Imaging Self-Scanner (LISS-III) Advanced Wide Field Sensor (AWi. FS) LISS-III and LISS-IV are $2, 750/scene; AWi. FS is $850/scene Website: http: //www. spaceimaging. com/prod ucts/irs/ 39

Image boundaries of scenes used 40 Image boundaries of scenes used 40

AWi. FS USDA Data Holdings 41 AWi. FS USDA Data Holdings 41

Disaster Monitoring Constellation (DMC) l l l l l DMC is a constellation of Disaster Monitoring Constellation (DMC) l l l l l DMC is a constellation of microsatellites being developed by Surrey Satellite Technology Limited (SSTL) that would provide daily global coverage A five satellite constellation could collect 400 -600 scenes/day Four satellites are currently operational; Al. SAT-1 was launched on November 28, 2002; UK-DMC, Nigeria. Sat-1, and BILSAT-1 were launched on September 27, 2003 An enhanced satellite for China will be launched in 2005 Orbital altitude/inclination: 686 km/98 degrees Nodal crossing: 10: 30 a. m. System life: 5 years Data characteristics are satellite dependent Availability of data and products, data policy, and pricing is TBD Website: http: //www. sstl. co. uk/ 42

DCWG Summary l l The DCWG concluded that preliminary results for IRS-P 6 and DCWG Summary l l The DCWG concluded that preliminary results for IRS-P 6 and CBERS-2 datasets do not indicate any irresolvable issues The IRS-P 6 satellite is a more mature system and better able in the near-term to provide useful datasets CBERS-2 IRMSS results are more problematic due to lack of information on data formats, processing, and operational modes, instrument inoperability (since 2005), and the lack of an identical sensor slated for the CBERS-2 B follow-on in 2007 Additional DCWG characterizations are necessary to better understand the sensors and correct for systematic errors, improve accuracies 43

LDGST Summary l There is no substitute for Landsat u u l l Single LDGST Summary l There is no substitute for Landsat u u l l Single source of systematic, global land observations Alternate sources may reduce the impact of a Landsat data gap We are characterizing multiple systems to understand which data sets may be compatible with the Landsat data record and can potentially supplement the Landsat data archive, but no decisions have been made yet Landsat Data Gap Study Team will: u u u Finalize recommendations and strategy for implementation Present findings to U. S. civil agency management and the White House Office of Space and Technology Policy Implement recommendations 44

Characterization & Data Gap Summary (1) l There are many instruments providing image data Characterization & Data Gap Summary (1) l There are many instruments providing image data for civil science purposes u u l l l USGS support of Global Earth Observing System of Systems and CEOS Office of the President OSTP - NASA/USGS Future of Land Imaging Team and LDGST Some available candidate remote sensing systems may be able to meet at least some of the needs of the Landsat user community. Technical advances have enabled the creation of many multispectral satellites All the data has value but it needs to be well understood u u System characterization and calibration needed l Cal parameter files and metadata important Product verification and validation needed l Cross calibration and international test areas must be used 45

Characterization & Data Gap Summary (2) l l l USGS is currently assessing Resource. Characterization & Data Gap Summary (2) l l l USGS is currently assessing Resource. Sat-1 (AWi. FS, LISS-III LISS-IV), and Surrey. Sat DMC, and working with INPE to access CBERS-2 Technologies are becoming robust enough to fill niches and cheap enough to cover many areas; however, there are major issues to be address: u Resolution and required bands – SWIR bands? u Accuracy and stability u Calibration concerns/Cross calibration concerns u Data acquisition u Data availability Cross calibration requires a stable base with cross band coverage (GEOSS GEO task) u l Strong need for a base, long term mission (Landsat) Precise high resolution data provides a great compliment to global assessment and is a must for ER 46