Moderate Resolution Imaging Spectroradiometer (MODIS) Products and Potential Applications For Environmental and Climatic Monitoring in China

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Moderate Resolution Imaging Spectroradiometer (MODIS) Products and Potential Applications For Environmental and Climatic Monitoring in China Jianhe (John) Qu Center for Earth Observing and Space Research (CEOSR) School of Computational Sciences (SCS) George Mason University 4400 University Drive MS 5C3 Fairfax, VA 22030-4444 Phone: 301-614-5337 E-mail: jqu@gmu.edu 03/23/2002 COAA Scientific Workshop --J. Qu 1

OUTLINE 1. Introduction 2. MODIS Direct Broadcast System 3. MODIS Products Summary 4. MODIS Potential Applications in China 03/23/2002 COAA Scientific Workshop --J. Qu 2

1. Introduction One of key instruments on NASA, Terra & Aqua satellites (EOS mission) Terra was launched in 1999 (descending node, 10:30 a.m. ) and Aqua to be launched in 2002 (ascending node, 1:30 p.m. ) with 705 km polar orbits Sensor Characteristics: 2300 km (cross track) and 2000 km (5 min. granule along track) 36 spectral bands ranging from 0.41 to 14.385 µm Spatial resolutions: 250 m (bands 1-2) 500 m (bands 3-7) 1000 m (bands 8-36) 03/23/2002 COAA Scientific Workshop --J. Qu 3

1. Introduction MODIS-Long Term Global Climate Monitoring Instrument 1. Four more MODIS sensors are planned to be built in the future by NASA. 2. Visible/Infrared Imager Radiometer Suite (VIIRS) on the National Polar-orbiting Operational Environmental Satellite System (NPOESS) is a MODIS type instrument. http://www.ipo.noaa.gov/viirs.html 3. The NPOESS Preparatory Project (NPP) is a bridge between the NASA EOS program and NPOESS. It is a joint NASA/IPO risk reduction instrument project. One of instruments on the platform is VIIRS. http://www.ipo.noaa.gov/npp.html 03/23/2002 COAA Scientific Workshop --J. Qu 4

1. Introduction MODIS -The first interdisciplinary remote sensing sensor. which can be used to monitor Earth s land, ocean and atmosphere, including snow/ice. 03/23/2002 COAA Scientific Workshop --J. Qu 5

1. Introduction MODIS Improved Spatial Resolution The MODIS 250m-resolution multi-spectral observations clearly discriminate different types of vegetation and urban areas in this image. The subsets show MODIS near-infrared band 2 (859nm) at 250m resolution (top right) and the corresponding NOAA14 AVHRR 1km band 2 (bottom right) over the Choptank River and the Cambridge area, in the Delmarva Peninsula. The improved spatial resolution of MODIS data over the heritage AVHRR data is apparent. 03/23/2002 COAA Scientific Workshop --J. Qu 6

1. Introduction Following issues barrier to wider use of MODIS data MODIS datasets are too large for most users Native MODIS data files are stored in HDF-EOS (Hierarchical Data Format Earth Observing System), a complex file format that does not currently have wide support. MODIS land and ocean product imagery is in a new map projection called the Integerized Sinusoidal (ISIN) projection which is ill-suited for North American and Asia areas. Most existing GIS software cannot handle MODIS datasets yet. 03/23/2002 COAA Scientific Workshop --J. Qu 7

1. Introduction (Versions) Beta Products (Version 001) Early release product, minimally validated and may contain significant errors Available to allow users to gain familiarity with data formats and parameters Not appropriate as the basis for quantitative scientific publications Provisional Products (Version 003) Product quality may not be optimal Incremental product improvements are still occurring General research community is encouraged to participate in the QA Users are urged to contact science team representatives prior to use of the data in publications May be replaced in archive when the validated product becomes available Validated Products Formally validated product, although validation is still ongoing Uncertainties are well defined Ready for use in scientific publications, and by other agencies 03/23/2002 COAA Scientific Workshop --J. Qu 8

2. MODIS Direct Broadcast System 1). The Direct Broadcast component of the EOS Terra and Aqua satellite broadcasts data via X-band to the ground. This page provides resources and links for organizations interested in production of calibrated radiances from the the MODIS instrument's direct broadcast data. 2). The data are transmitted directly to the ground in real time to stations within line-of-sight of the satellite as it passes overhead. This allows receivers in a more timely manner than from the Distributed Active Archive Centers (DAACs). 3). Most MODIS science algorithms are not designed for MODIS DB system. 4). There are more than 15 MODIS DB ground stations (9 in Beijing) in China right now, and the total MODIS DB station number will increase in the near future. 03/23/2002 COAA Scientific Workshop --J. Qu 9

2. MODIS Direct Broadcast System From: http://daac.gsfc.nasa.gov/daac_docs/direct_broadcast/db.html 03/23/2002 COAA Scientific Workshop --J. Qu 10

3.1 MODIS Product Summary (1) Data Product Description Average Size (Mb) Raw data MODIS instrument produces the raw data per day (70 Gb/day) MODAPS Data MODIS Data Production System (500Gb/day) Radiance Counts Level 1A Radiance Counts (MOD01) 407.5 Geo-location Level-1 A Geo-location data (MOD03) 61.7 Calibrated Radiance Level 1-B, Calibrated Radiance 1KM, HKM and QKM (295 Gb/day) Calibrated Radiance 1KM Level-1B Calibrated Radiance 1KM (MOD021KM) 259.5 Calibrated Radiance HKM Level-1B Calibrated Radiance HKM (MOD02 HKM) 165.5 Calibrated Radiance QKM Level-1B Calibrated Radiance QKM (MOD02 QKM) 171.7 Onboard calibration Level 1B Onboard Calibration/Engineering data (MOD02OBC) 60.5 Aerosol Products Level 2 Aerosol Products, Aerosol optical thickness, aerosol type, 10.7 aerosol mass concentration, particle size distribution, optical properties and radiative forcing (MOD04_L2). Water Vapor Products Water Vapor amounts (MOD05_L2). 11.5 03/23/2002 COAA Scientific Workshop --J. Qu 11

3.1 MODIS Product Summary (2) Data Product Description Average Size (Mb) Cloud Products Level 2 Cloud Product consists of cloud top physical parameters 45.9 like temperature pressure, cloud phase etc. and other derived parameters. This product consists of 46 parameters (MOD06_L2). Atmospheric Profiles Level 2 Atmospheric Profiles Consists of Parameters describing 33.7 total ozone burden, atmospheric stability, atmospheric temperature and moisture profiles (MOD07_L2). Cloud Mask Products Level 2 Could Mask Indicates whether a given field of view (FOV) 48.6 of the Earth surface is unobstructed by clouds, and in view is affected by cloud shadows (MOD35_L2). Surface Reflectance Surface Reflectance 500 m (MODIS 09A1 ) Surface Temperature Level-2 Land Surface Temperature (MOD11L2) Level-3 Land Surface Temperature 1km (MODIS11A1) 03/23/2002 COAA Scientific Workshop --J. Qu 12

3.1 MODIS Product Summary (3) Data Product Description Average Size (Mb) Land Cover Land Cover/Change (MOD12) Vegetation Index Thermal Anomalies/Fire Leaf Area Index Net Primary Production Albedo BRDF Vegetation Indices 500 m (MOD13A1) Vegetation Indices 1 km (MOD13A2) Thermal Anomalies/Fire (MOD14). 8-Day Thermal Anomalies/Fire (MOD14A). Leaf Area Index 1 km (MOD15A2). Net Primary Production (MOD17). Minimal Albedo (MOD43B3) Nadir BRDF Adjusted Reflectance (MOD43B3) Vegetation Cover Vegetation Cover Conversion (MOD44). 03/23/2002 COAA Scientific Workshop --J. Qu 13

3.1 MODIS Products Summary (4) Granule is the smallest aggregation of data which is independently managed (i,e., described, inventoried, retrievable). One granule (July 07, 2000 03:00-03:05 GMT) MODIS level-1b true color image shows the ground coverage. 03/23/2002 COAA Scientific Workshop --J. Qu 14

3.2 MODIS Atmosphere Products (1) The MODIS Cloud Mask The MODIS Cloud Mask product (MOD35_L2) is a daily, global Level 2 product generated at 1-km and 250-m (at nadir) spatial resolutions. The algorithm employs a series of visible and infrared threshold and consistency tests to specify confidence that an unobstructed view of the Earth's surface is observed. An indication of shadows affecting the scene is also provided. The 250-m cloud-mask flags are based on the visible channel data only. Radiometrically accurate radiances are required, so holes in the Cloud Mask will appear wherever the input radiances are incomplete or of poor quality. The MODIS Aerosol Product The MODIS Aerosol Product (MOD04_L2) monitors the ambient aerosol optical thickness over the oceans globally and over a portion of the continents. Further, the aerosol size distribution is derived over the oceans, and the aerosol type is derived over the continents. Daily Level 2 data produced at the spatial resolution of a 10 10 1-km (at nadir)-pixel array. 03/23/2002 COAA Scientific Workshop --J. Qu 15

3.2 MODIS Atmosphere Products (2) The MODIS Precipitable Water product The MODIS Precipitable Water product (MOD05_L2) consists of column water-vapor amounts. During the daytime, a near-infrared algorithm is applied over clear land areas of the globe and above clouds over both land and ocean. Over clear ocean areas, water-vapor estimates are provided over the extended glint area. An infrared algorithm for deriving atmospheric profiles is also applied both day and night for Level 2. MODIS Cloud Product (MOD06_L2) The MODIS Cloud Product (MOD06_L2) combines infrared and visible techniques to determine both physical and radiative cloud properties. Daily global Level 2 data are provided. Cloud-particle phase (ice vs. water, clouds vs. snow), effective cloud-particle radius, and cloud optical thickness are derived using the MODIS visible and near-infrared channel radiances. Atmospheric Profile Products(MOD07_L2) total-ozone burden, atmospheric stability, temperature and moisture profiles, and atmospheric water vapor. 03/23/2002 COAA Scientific Workshop --J. Qu 16

3.3 MODIS Land Products Summary 1. MOD09 Surface Reflectance 2. MOD11 Land Surface Temperature and Land Surface Emissivity 3. MOD12 Land Cover/Change 4. MOD13 Vegetation Indices 5. MOD14 Thermal Anomalies/Fire 6. MOD15 Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation (FPAR) 7. MOD43 Bidirectional Reflectance Distribution Function and Albedo 8. MOD44 Vegetation Cover Conversion/Continuous Field 9. MODMGGA Global Geolocation Angle http://edcdaac.usgs.gov/modis/dataprod.html 03/23/2002 COAA Scientific Workshop --J. Qu 17

3.3 MODIS Data Summary (Land Products) Global MODIS Daily Land Surface Reflectance Global daily MODIS land surface reflectance true color (band 01, 04 and 03, image (2000313) Credit to: MODLAND team. 03/23/2002 COAA Scientific Workshop --J. Qu 18

3.3 MODIS Data Summary (Land Products) Global MODIS 8 Days Land Surface Reflectance Global 8 day MODIS land surface reflectance true color (band 01, band 04 and band 03,image (started 2000313). Credit to: MODLAND team. 03/23/2002 COAA Scientific Workshop --J. Qu 19

3.3 MODIS Product Summary (Land Products) 250 m 16 days (starting Aug. 13, 2001) EVI coverage in USA continental regions. 03/23/2002 COAA Scientific Workshop --J. Qu 20

3.4 MODIS Ocean Product Summary Ocean Product Group 1 Sea Surface Temperature 4 Day, Night, 4µm, 11µm, (skin, bulk) 2 Water-leaving radiance 11 nlw412-678, τ a,865, /atmos correction eps, models 3 Chlorophyll Case 1 and 2 6 empirical, semi-anal., 2 MODIS, SeaWiFS 4 Fluorescence 5 Included Parameters FLH, efficiency, IPAR, ARP, baseline Level-2 5'_Granules swath, 1km swath, 1km Level-3 Global Daily/Weekly/Monthly 4.6 km, 36 km, 1 degree 4.6 km, 36 km, 1 degree swath, 1km 4.6 km, 36 km, 1 degree swath, 1km 4.6 km, 36 km, 1 degree 5 Sediments & Optical Attenuation 2 Total S. S., K 490 swath, 1km 4.6 km, 36 km, 1 degree 6 Coccoliths & Calcite 3 Coccolith Calcite, chl correction swath, 1km 4.6 km, 36 km, 1 degree 7 Phycobilipigments 2 PEB, PUB (beta) swath, 1km 4.6 km, 36 km, 1 degree 8 Bio-optical Properties 7 9 Ocean Net Primary Production 6 a CDOM, a λ,412-550, a total, a chl, 2 weekly analytical, empirical annual, MLD, PAR swath, 1km Total 42 parameters, Fields include means, flags, QA et al. 4.6 km, 36 km, 1 degree 03/23/2002 COAA Scientific Workshop --J. Qu 21 NA 4.6 km, 36 km, 1 degree

4. MODIS Potential Applications in China Potential Applications of Natural Resource/ Disaster and Environment Monitoring (1) Land Surface Use and Coverage Study (2) Natural Resource Assessment (3) Meteorological and Environmental Monitoring (4) Natural Disaster Observation 03/23/2002 COAA Scientific Workshop --J. Qu 22

4. MODIS Potential Applications in China A simple example of a land surface products that can be produced on a bi-weekly bases is the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). Vegetation indices have a long history of use throughout a wide range of disciplines. Some examples are listed below: 1) Global biogeochemical, climate, and hydrological modeling 2) Net primary products and carbon balance study 3) Crop monitoring 4) Drought and fire detection 5) Landscape disturbances (fire scars and volcanic et al.) 6) Land cover and land cover change monitoring 7) Publican health issues 03/23/2002 COAA Scientific Workshop --J. Qu 23

4.1 MODIS Potential Applications in China Description: A thick haze of aerosols coves eastern China in this true-color MODIS image from November 9, 2001. Although there are many naturally occurring aerosols, this is China's most developed, industrialized region, and the aerosols are most likely pollution. Beneath the haze, the Yellow River can be seen running northeast and emptying into Bo-Hai Bay (upper right). (Credit to NASA Visible Earth) 03/23/2002 COAA Scientific Workshop --J. Qu 24

4.2 Dust Storm Monitoring Dust storm occurred every spring in last decade over northern parts of China and Mongolia. This picture shows the dust coverage in Beijing at 10:30AM March 20, 2002 (Picture courtesy China News Agency). 03/23/2002 COAA Scientific Workshop --J. Qu 25

4.2 Dust Storm Monitoring Dust storm in XiAn March 20, 2002 (Picture courtesy China News Agency). 03/23/2002 COAA Scientific Workshop --J. Qu 26

4.2 Dust Storm Monitoring Using MODIS Dust cloud over China. A large dust plume during March 17, 2002 shows in this image (from NASA Visible Earth and image courtesy Jacques Descloitres). 03/23/2002 COAA Scientific Workshop --J. Qu 27

4.2 Dust Storm Monitoring Dust cloud over Sea of Japan during March 19, 2002 (from NASA Visible Earth and image courtesy SeaWiFS project). 03/23/2002 COAA Scientific Workshop --J. Qu 28

4.3 MODIS Applications in Western China Region 1. Most of the China Western China regions are remote areas. 2. There are limited environmental and meteorological observation stations in these regions. 3. Chinese government has spent a lot of effort to develop the Western China Region. 4. MODIS will be very useful tool for environmental monitoring and transportation system designing. 03/23/2002 COAA Scientific Workshop --J. Qu 29

Acknowledgments We would like to express gratitude to the MODIS science teams, Remote Sensing Information Partner (RSIP) program and MODIS Data Support Team (MDST) at NASA/GSFC/GDISC. MODIS specification and product information was obtained from the MODIS Web Page http://modis.gsfc.nasa.gov Some MODIS images were obtained from the NASA Visible Earth Web Page http://visibleearth.nasa.gov/ 03/23/2002 COAA Scientific Workshop --J. Qu 30