Presentation on theme: "Scaling and Assimilation of Soil Moisture and Streamflow (SASMAS): project overview and preliminary results G Willgoose (U. Leeds, UK), H Hemakumara (U."— Presentation transcript:
Scaling and Assimilation of Soil Moisture and Streamflow (SASMAS): project overview and preliminary results G Willgoose (U. Leeds, UK), H Hemakumara (U. Newcastle, Australia) C Rudiger (U. Melbourne, Australia) B Jacobs, J Kalma (U. Newcastle, Australia) J Walker (U. Melbourne, Australia) G Hancock, P Saco (U. Newcastle, Australia) P Houser (NASA Goddard, Hydrology Section)
Validation of the soil moisture products from Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) … 50km pixels. Development of scaling relationships for soil moisture Estimating the spatial distribution and averages of soil moisture in large catchments by assimilating near surface moisture measurements and streamflow measurements Estimation of temporal variation of soil moisture Assimilating streamflow measurements to estimate soil moisture (specifically for forested areas) TODAY: Focussing on preliminary data from SASMAS1 field campaign in October, 2003. SASMAS Objectives
Merriwa SASMAS Location Rainfall: 500-1000 mm Pan Evaporation: 1800 P/E: 0.3-0.6 Daily Temp: 16-30 (summer) 3-17(winter)
Soils and Geology Basalt Sandstone Soils Clay Silts
Typical Data from Permanent Sandstone Monitoring Site
SASMAS 01 Sampling 40 x 50km area North of Goulburn River within unforested region 4 teams over 3 days Sampled area about scale of AMSR pixel 225 soil moisture samples sites (4 gravimetric, 5 theta probe (TDR)), 194 veg samples
Vegetation Soil Moisture and Biomass Correlations (?) No Apparent Correlation Weak Positive Correlation
Results from Ground observations Avg MC, v/v (0-6cm) = 0.141 Avg MC, v/v (0-1cm) = 0.109 AMSR-E moisture values (v/v) using old (invalid?) NASA algorithm Nov 7 – 0.15 Nov 8 – 0.15 Nov 9 – 0.15 AMSR Validation: Preliminary Results Comparison good (subject to the revised NASA AMSR-E inversion algorithm). No vegetation moisture correction in ground observations.
Conclusions Several additional field campaigns planned in 2004. Probably less extensive vegetation sampling allowing a greater density of soil moisture measurements. SASMAS 01 has delivered an extensive distributed soil moisture, soil temperature and vegetation data set for semi-arid conditions for dry (extreme drought) springtime conditions. Future campaigns will concentrate on wetter conditions. Currently have 16 months of distributed continuous data soil moisture at 26 sites and 3 depths, and soil temperature, with nested catchments with runoff data. Data for scaling studies of soil moisture and assimilation of distributed soil moisture from river discharges. Website with data and publications: (www.civag.unimelb.edu.au/~jwalker/data/sasmas)www.civag.unimelb.edu.au/~jwalker/data/sasmas Funding: Australian Research Council, NASA.