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HR: 1340h
AN: H33F-1222 Poster
TI: SMOS ground validation in Australia : results from summer and winter campaigns
AU: *Rudiger, C
EM: crudiger@unimelb.edu.au
AF: Dept. of Civil Engineering, Monash University, Clayton, VIC, Australia
AU: Walker, J P
EM: jeff.walker@monash.edu
AF: Dept. of Civil Engineering, Monash University, Clayton, VIC, Australia
AU: Kerr, Y H
EM: yann.kerr@cesbio.cnes.fr
AF: Cesbio, Toulouse, France
AU: Kim, E J
EM: ed.kim@nasa.gov
AF: NASA - Goddard, Greenbelt, MD, USA
AB: With the recent launch of the Soil Moisture and Ocean Salinity (SMOS) mission the remote sensing community is becoming engaged in airborne campaigns for their validation. This study covers two aspects, the actual ground validation and also the requirements of spatial coverage. Both campaigns covered an extensive area of up to 20 independent SMOS footprints and the relationship of the large scale averages with the SMOS observations is presented here. The latter point is necessary, given the financial and logistical constraints on the area that can be covered by airborne simulators, giving scientifically sound advice on the fractional footprint coverage requirements by campaigns for these low resolution sensors a paramount importance. Using high resolution airborne data from two extensive airborne campaigns in south-eastern Australia the fractional coverage requirement for L-band passive microwave satellite missions is assessed using a sub-sampling technique of the flight lines through a passive microwave footprint. It is shown that a minimum 50% coverage of the total footprint size will typically be required to ensure that the correct footprint mean is estimated with an expected sampling error of less than 4K; the design sensitivity of SMOS.
DE: [1855] HYDROLOGY / Remote sensing
DE: [1866] HYDROLOGY / Soil moisture
SC: Hydrology (H)
MN: 2010 Fall Meeting

HR: 0815h
AN: H31K-02
TI: The Soil Moisture Active Passive Experiments (SMAPEx) for SMAP Algorithm Development (Invited)
AU: *Panciera, R
EM: panr@unimelb.edu.au
AF: Civil and Environmental Engineering, The University of Melbourne, Melbourne, VIC, Australia
AU: Walker, J P
EM: jeff.walker@monash.edu
AF: Civil Engineering, Monash university, Melbourne, VIC, Australia
AU: Ryu, D
EM: dryu@unimelb.edu.au
AF: Civil and Environmental Engineering, The University of Melbourne, Melbourne, VIC, Australia
AU: Gray, D
EM: dgray@eleceng.adelaide.adu.au
AF: School of Electrical and Electronic Engineering, The University of Adelaide, Adelaide, VIC, Australia
AU: Jackson, T J
EM: tom.jackson@ars.usda.gov
AF: Hydrology and Remote Sensing Laboratory, United States Department of Agriculture, Beltsville, VIC, Australia
AU: Yardley, H
EM: hyardley@eleceng.adelaide.adu.au
AF: School of Electrical and Electronic Engineering, The University of Adelaide, Adelaide, VIC, Australia
AB: The availability of global L-band observations from passive (the recently launched SMOS), and active (such as the PALSAR) microwave sensors has boosted the interest in making joint use of the two techniques to improve the retrieval of global near-surface soil moisture at unprecedented resolutions. The Soil Moisture Active Passive (SMAP) mission (scheduled launch, 2014) will fully exploit this synergy by providing concurrent active (radar) and passive (radiometer) microwave observations, resulting in passive-only, active-only and a merged active-passive soil moisture products at spatial resolutions of respectively 40km, 3km and 9km. The Soil Moisture Active Passive Experiments (SMAPEx) are a series of airborne field experiments specifically designed for algorithm development for SMAP and currently ongoing in the context of the SMAP pre-launch cal/val activities for Australia. Four SMAPEx campaigns are scheduled across the 2010-2011 seasonal cycle, with the first campaign (SMAPEx-1) successfully conducted on moderately wet winter conditions (July 5-10, 2010) and the second campaign (SMAPEx-2), scheduled for the summer (December 4-8,2010). SMAPEx is making use of a novel SMAP airborne simulator, including an L-band radar and radiometer to collect SMAP-like data over a well monitored semi-arid agricultural area in the Murrumbidgee catchment in south-eastern Australia. High resolution radar and radiometer observations collected during SMAPEx are supported by extensive ground sampling of soil moisture and ancillary data, allowing for testing of a variety of algorithms over semi-arid agricultural areas, typical of the Australian environment but similar to large areas of the central continental USA, including radiometer-only, radar-only, merged active-passive, downscaling and radar change-detection algorithms. In this paper a preliminary assessment of the performance of the radar-only and radiometer-only retrieval algorithms proposed as baseline for SMAP is presented. The soil moisture retrieved from active and passive microwave airborne observations collected during the SMAPEx-1 campaign is compared with extensive spatial data collected at focus areas. The quality of the individual retrievals is discussed in relation with different land surface conditions, ranging from intensive cropping to dryland grassland areas.
DE: [1866] HYDROLOGY / Soil moisture
DE: [6969] RADIO SCIENCE / Remote sensing
SC: Hydrology (H)
MN: 2010 Fall Meeting