A Brief Overview of Passive Microwave Experiments over Land

Transcription

1 A Brief Overview of Passive Microwave Experiments over and Richard de Jeu Dept. of Hydrology and Geo-Environmental Sciences Vrije Universiteit Amsterdam, the Netherlands

2 Outline Overview Discussion Future

3 Overview First experiments in aboratory > Validation of Theory Bare soil experiments > Sand/Gravel BARC experiment > different crops and bare soil > valuable database (data available at hydrolab.arsusda.gov) PERIOD GROUP/ PROJECT OC. RADIOM. FREQ. (Ghz) SURFACE REF 1968 Snow Edgerton et al NASA-JP ab.,x,ka Bare Blinn et al, NASA-JP ab Bare Njoku and Kong, Tex.Uni Texas Bare Newton, BARC Beltsville(US) TruckRad,C,X, Ka Agri.C Wang et al., 1983

4 Overview More Groups get involved: The Italians: The Swiss: > Multi freq. measurements above crops > vegetation study > Bare soil emissivity catalogue > Transmissivity measurements of a forest PERIOD GROUP/ PROJECT OC. RADIOM. FREQ. (Ghz) SURFACE REF 1980 Microrad Florence (IT) IROE,C,X,Ku,Ka Agri.C. Paloscia et al., U.Bern Var. PAMIR/ RASAM Ghz Var. Matzler (1994), Wegmuller et al, 1994

5 Overview Microwave experiments at NOPEX and EFEDA > Extensive ω-τ study Cal-Val experiments for SSM/I (REBEX) TMRS in Alaska PERIOD GROUP/ PROJECT OC. RADIOM. FREQ. (Ghz) SURFACE REF 1991 BARC Beltsville (US) RusRad,C Agri.C. Owe (Pers Comm) PORTOS Avignon (F) PORTOS,C, Agri, bare Wigneron et al REBEX Var. TMRS Ku,Ka Var. ich.edu/grs/ 1994 NOPEX Uppsala (SW) RusRad,C Agri.C. Owe (Pers Comm) 1994 EFEDA Tomelloso (SP) RusRad,C Vineyards Gouweleeuw, 2000

6 Overview Big S.Great Planes exp. (ground/air) Development of new Sensors DSD SWaMP- PERIOD GROUP/ PROJECT OC. RADIOM. FREQ. (Ghz) SURFACE REF 1997/99 SGP97/99 Washita (US) SMR,S Agri.C. susda.gov/sgp99 7/ 1999 ESSC Reading (UK) SWaMP- Bare Pearson et al., UMICH Michigan (US) DSD? mich.edu/grs/

7 Overview More Groups,..More Sensors > ong term measurements > High temporal resolution EWIS at Fauga PERIOD GROUP/ PROJECT OC. RADIOM. FREQ. (Ghz) SURFACE REF 2001 INRA Avignon (F) EMIRAD Corn, Bare Parde, ETH Eschikon (CH) EBARA/ MIRA,X Bare Schneeberger, MASMEX Alps (IT),C,Ka,Ku snow Macelloni et al., SMOSREX Fauga (F) EWIS Bare,Fallow De Rosnay et al

8 Overview > Simultaneous measurements of different sites > Important forest studies EBARA PERIOD GROUP/ PROJECT OC. RADIOM. FREQ. (Ghz) SURFACE REF 2003 VUA Wageningen (N) EBARA Bare,grass De Jeu et al 2003 REFEX Valencia (SP) AURA Vineyards Vall-llossera et al ETH Eschikon (CH) EBARA Grass Schwank et al 2004 BRAY es andes (F) EMIRAD Forest Wigneron et al 2005 ETH Julich (G) EBARA Forest Schwank et al

9 Discussion Impressive list of field observations Many groups are involved nowadays Improvement radiometers At least 7 field radiometers operational (or ready to use): 1. EWIS (CNES-CESBIO-ONERA, France) 2. EBARA (ETH, Swiss) 3. AURA (Univ. Catalunya, Spain) 4. DSD (Univ.Mich., USA) 5. SMR (NASA/GSFC, USA) 6. SWaMP- (ESSC, UK) 7. Multifreq. Rad (CNR-IFAC, Italy) 8. EMIRAD (Tech. Univ. Denmark) 9. Radiometer of Ontario group (Duke et al.)? 10. Radiometer of group from India (Singh et al.)?

10 Discussion At least a dozen airborne missions over a variety of land surfaces, for example: PBMR during FIFE, HAPEX MOBIHY PORTOS during PORTOS93, HAPEX SAHE EMIRAD during NOPEX ESTAR during SGP97 SGP99 PAS during SGP99 SMEX02 2DSTAR during SMEX03 SMEX04 EMIRAD in Airplane

11 Discussion Development of new airborne instruments and experiments: PMR +, NAFE (C. Rudiger/J. Walker) STAR-IGHT (U.Mich) MIRAMAP (private company at ESA) French ATR42 for SMOS cal-val?

12 Discussion However; We have to be careful not to do similar experiments Keep an open discussion Start comparison studies Use historical information ook for more collaboration

13 Future Do we need future experiments? Comparison studies between different sensors Measurements of urban areas > RFI problem Transmissivity studies Comparison of flux measurements with microwave??