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DEPARTMENT OF GEOMATIC ENGINEERING Progress and Plans for MODIS validation and new algorithm development Jan-Peter Muller , University College London Professor of Image Understanding and Remote Sensing MODIS & MISR Science Team Member (NASA EOS Project), HRSC (ESA Mars Express) CoI with contributions from Catherine Naud, SJ Chan, Chris Doll, Jung-Rack Kim, Zhenhong Li, Mercedes Sole-Chomorro (UCL) Objectives for next 3 years Develop automated algorithms for the extraction of geophysical parameters from MODIS using geomatic engineering, image understanding (IU) techniques and 3D radiative transfer theory Develop extensions of existing MOD43 global BRDF/Albedo product to take topography into explicit account Develop new products for the climate modelling community based on fusion of MODIS and SRTM near-global topography Develop fused MODIS-MISR products to exploit the complementarity between their spectral and angular aspects (clouds, aerosols, surface BRDF/albedo) Develop fused MODIS-DMSP products to explore the anthrogenic components of global change Develop global validation strategies using independent data-sets as well as inter- comparison between different sensors on the same EO platform. Publish individual validation case studies on the web to provide a detailed reference for product users. Validation of Cloud and Water Vapour Properties from the NASA Terra MODIS and MISR instruments (EU-CLOUDMAP2) Long time series inter-comparisons of cloud-top heights and cloud fractions from ground-based active and passive instruments at ARM-SGP, OK and Chilbolton Radar Observatory, UK Good agreement between thermal IR all-sky camera and MODIS cloud fractions All cases per cloud situation: good agreement between MISR, radar and MERIS for single level (non-broken) clouds (#: large box indicates high cloud whilst smaller boxes indicate mid-level cloud) Validation of Aerosol Properties from the NASA Terra MODIS and MISR instruments with street-level urban pollution A E R O S O L D A T A URBAN AEROSOL DATA SATELLITE AEROSOL RS DATA Cloud-free atmosphere retrievals MODIS AEROSOL P RODUC T MIS R AEROSOL PRODUCT L.A PM-10 & PM-2.5 ( µ g/m 3 ) London PM-10 & PM-2.5 ( µ g/m 3 ). GROUND BASED AERONET DATA AOT Validation 30-arc-second Global Population Dataset (LANDSCAN) 30-arc-second Global elevation data (GTOPO30) AOT Ångström exponent AOT R E S U L T S: Inter-comparison MISR /MODIS AOT vs. PM-2.5 for L.A.& London 0 0.3 0 .35 0 10 20 30 40 50 60 70 0 0.1 0.2 0.3 0.4 0.5 0.6 MODIS AOT MIS R AOT MISR AOT 13-11-00 14-2.01 24-1-01 29-5-01 13-2-01 30-5-01 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 0 5 10 15 20 25 30 35 40 45 MODIS AOT 16-3-01 17-4-01 3-4-01 0 0.2 1.4 1.6 1.8 2 0 10 20 30 40 50 MISR AOT MISR AOT MODIS AOT PM -2.5 24-hour aver. PM -2.5 24-hour aver. PM -2.5 24-hour aver. Los Angeles, 25th Nov. 2000 London, different dates • MISR seems to correlate better with PM2.5 than MODIS • Larger number of stations would give less uncertainty on the results R E S U L T S: Inter-comparison MODIS/MISR AOT vs. PM-10 and PM-2.5 for L.A. 13th Nov. 2000 North Sea London English Channel 17th April 2001 North Sea London English Channel MODIS AOT M ISR AOT Locations of the monitoring stations within the London urban area •Difficult to obtain total coverage over the London urban area due to cloud cover • PM10 and PM2.5 is given in 24h and hourly averages • PM2.5 is reported at only two stations in central London: Marylebone and Bloomsbury R E S U L T S: Inter-comparison MISR /MODIS AOT vs. Global elevation dataset Hill-shaded DEM (GTOPO30), California (U.S.A) MODIS AOT 17 th Jan 2001 MISR AOT 4th Feb 2001 • Good visual correlation between AOT retrievals and topography for both California • Strong temperature inversions in the L.A valley is one of the causes of long, low visibility episodes and higher health risks • San Joaquin Valley is trapped between the Sierra Nevada Mountains and the coastal range where pollution concentrations are high Land Surface Albedo Properties from MODIS instrument Anthropogenic activities from the DMSP OLS instrument Night-time Lights as an indicator of human activity Excellent at identifying human activities in developed parts of the world Also highlights human activity at sea such as shipping fleets and off-shore gas fields. Clear economic component when analysing the data Mapping CO 2 from night-time lights MODIS 16-day broadband albedo at 1km over Europe Anthropogenic signatures in MODIS Albedo Multi-spectral image 1 m resolution DEM NDVI 1 m pan image Example Application of IU techniques to Mars Reliable tree and building detection using the fusion of multi- spectral and Digital Surface Model information and both supervised and unsupervised classification. 3D radiative transfer can then be applied to the 3D landscape objects to understand better the spectral and angular signatures seen by MODIS Automated crater detection in MGS-MOC images Automated building detection from 1m IKONOS Such automated high-level feature extraction based on image understanding techniques will be applied to MODIS products to try to extract climate change signatures -0.20 -0.16 -0.12 -0.08 -0.04 -0 Albedo Mapping economic activity from night-time lights MERIS and Radar CTH (km) MISR, MODIS and Radar CTH (km) Cloud situation Date and location overpass (UT) overpass (UT) Low continuous 2003-02-15, SGP 16:58 1.9 2.0 17:30 2.2 0.8 2.1 2003-05-11, CFARR 10:42 CTHs too variable 11:10 1.0 0.6 1.1 Low broken 2003-06-12, CFARR 10:35 1.7 1.6 11:10 1.5 0.9 2.0 CFARR Mid-level continuous 2003-06-07, SGP 16:39 4.3 4.6 17:30 4.5 6.1 4.7 Mid-level broken 2003-06-09, SGP 17:15 4.9 6.2 17:15 5.4 7.1 6.2 2003-05-15, SGP 17:01 5.0 11.7 17:25 9.0 10.6 11.6 High multi- layer SGP DATE Time (UT ) ASTIC CF (%)/manual ASTIC image ASTIC Cloud mask Comments 19 June 2003 11:14:06 60.8/100 2003 03 July 2003 11:22:06 80.3 05 July 2003 11:14:06 61.1/100 06 July 2003 11:51:06 71.8/92 2003 08 July 2003 11:44:06 58.1/100 Excellent agreement between MOD05 and GPS Precipitable Water Vapour Barnsley, M.J., P.D. Hobson, A.H. Hyman, W. Lucht, J.P. Muller, and A.H. Strahler, Characterizing the spatial variability of broadband albedo in a semidesert environment for MODIS validation, Remote Sensing of Environment, 74 (1), 58-68, 2000. Doll, C.N.H., J.P. Muller, and C.D. Elvidge, Night-time imagery as a tool for global mapping of socioeconomic parameters and greenhouse gas emissions, Ambio, 29 (3), 157-162, 2000. Li, Z.H., J.P. Muller, and P. Cross, Comparison of precipitable water vapor derived from radiosonde, GPS, and Moderate- Resolution Imaging Spectroradiometer measurements, Journal of Geophysical Research-Atmospheres, 108 (D20), art. no.-4651, 2003. Muller, J.P., A. Mandanayake, C. Moroney, R. Davies, D.J. Diner, and S. Paradise, MISR stereoscopic image matchers: Techniques and results, Ieee Transactions on Geoscience and Remote Sensing, 40 (7), 1547-1559, 2002. Naud, C., J.P. Muller, and E.E. Clothiaux, Comparison of cloud top heights derived from MISR stereo and MODIS CO2-slicing, Geophysical Research Letters, 29 (16), art. no.-1795, 2002. Naud, C., J.P. Muller, M. Haeffelin, Y. Morille, and A. Delaval, Assessment of MISR and MODIS cloud top heights through intercomparison with a back-scattering lidar at SIRTA, Geophysical Research Letters, 31 (4), art. no.-L04114, 2004. Sample publications (2000-2004)
