Monitoring agricultural soil moisture extremes in Canada using passive microwave remote sensing

Abstract Current methods to assess soil moisture extremes rely primarily on point-based in situ meteorological stations which typically provide precipitation and temperature rather than direct measurements of soil moisture. Microwave remote sensing offers the possibility of quantifying surface soil moisture conditions over large spatial extents. Capturing soil moisture anomalies normally requires a long temporal record of data, which most operating satellites do not have. This research examines the use of surface soil moisture from the AMSR-E passive microwave satellite to derive surface soil moisture anomalies by exploiting spatial resolution to compensate for the shorter temporal record of the satellite sensor. Four methods were used to spatially aggregate information to develop a surface soil moisture anomaly (SMA). Two of these methods used soil survey and climatological zones to define regions of homogeneity, based on the Soil Landscapes of Canada (SLC) and the EcoDistrict nested hierarchy. The second two methods (ObShp3 and ObShp5) used zones defined by a data driven segmentation of the satellite soil moisture data. The level of sensitivity of the calculated SMA decreased as the number of pixels used in the spatial aggregation increased, with the average error reducing to less than 5% when more than 15 pixels are used. All methods of spatial aggregation showed somewhat weak but consistent relationship to in situ soil moisture anomalies and meteorological drought indices. The size of the regions used for aggregation was more important than the method used to create the regions. Based on the error and the relationship to the in situ and ancillary data sets, the EcoDistrict or ObShp3 scale appears to provide the lowest error in calculating the SMA baseline. This research demonstrates that the use of spatial aggregation can provide useful information on soil moisture anomalies where satellite records of data are temporally short.

[1]  Computing the monthly Palmer Drought Index on a weekly basis: A case study comparing data estimation techniques , 2005 .

[2]  N. Guttman On the Sensitivity of Sample L Moments to Sample Size , 1994 .

[3]  R. Jeu,et al.  The European heat wave 2003: early indicators from multisensoral microwave remote sensing? , 2009 .

[4]  Yang Hong,et al.  Precipitation Extremes Estimated by GPCP and TRMM: ENSO Relationships , 2007 .

[5]  G. W. Snedecor STATISTICAL METHODS , 1967 .

[6]  F. F. Pruski,et al.  Climate‐induced changes in erosion during the 21st century for eight U.S. locations , 2002 .

[7]  N. Guttman COMPARING THE PALMER DROUGHT INDEX AND THE STANDARDIZED PRECIPITATION INDEX 1 , 1998 .

[8]  R. Jeu,et al.  Multisensor historical climatology of satellite‐derived global land surface moisture , 2008 .

[9]  D. Nychka,et al.  Bayesian Spatial Modeling of Extreme Precipitation Return Levels , 2007 .

[10]  T. McKee,et al.  THE RELATIONSHIP OF DROUGHT FREQUENCY AND DURATION TO TIME SCALES , 1993 .

[11]  Li Li,et al.  A preliminary survey of radio-frequency interference over the U.S. in Aqua AMSR-E data , 2004, IEEE Transactions on Geoscience and Remote Sensing.

[12]  N. Guttman ACCEPTING THE STANDARDIZED PRECIPITATION INDEX: A CALCULATION ALGORITHM 1 , 1999 .

[13]  Toby N. Carlson,et al.  Decoupling of surface and near‐surface soil water content: A remote sensing perspective , 1997 .

[14]  Randal D. Koster,et al.  Soil Moisture Memory in Climate Models , 2001 .

[15]  B. Bonsal,et al.  Historical comparison of the 2001/2002 drought in the Canadian Prairies , 2007 .

[16]  Heather McNairn,et al.  Evaluation of soil moisture derived from passive microwave remote sensing over agricultural sites in Canada using ground-based soil moisture monitoring networks , 2010 .

[17]  W. Alley The Palmer Drought Severity Index: Limitations and Assumptions , 1984 .

[18]  Paul Harker,et al.  Agroclimatic Atlas of Alberta, 1971-2000 , 2006, Cartogr. Int. J. Geogr. Inf. Geovisualization.

[19]  Richard R. Heim,et al.  BEGINNING A NEW ERA OF DROUGHT MONITORING ACROSS NORTH AMERICA , 2002 .

[20]  F. Kogan,et al.  Global Drought Watch from Space , 1997 .

[21]  E. Wood,et al.  A simulated soil moisture based drought analysis for the United States , 2004 .

[22]  A. Shepherd,et al.  Impact of climate change scenarios on the agroclimate of the Canadian prairies , 2003 .

[23]  M. Palecki,et al.  THE DROUGHT MONITOR , 2002 .

[24]  Michael J. Hayes,et al.  Appropriate application of the standardized precipitation index in arid locations and dry seasons , 2007 .

[25]  R. Srinivasan,et al.  Development and evaluation of Soil Moisture Deficit Index (SMDI) and Evapotranspiration Deficit Index (ETDI) for agricultural drought monitoring , 2005 .

[26]  Vijendra K. Boken,et al.  Monitoring and Predicting Agricultural Drought: A Global Study , 2005 .

[27]  Arno Schäpe,et al.  Multiresolution Segmentation : an optimization approach for high quality multi-scale image segmentation , 2000 .

[28]  J. K. Henshall,et al.  Soil structural quality, compaction and land management , 1997 .

[29]  A. Berg,et al.  Relationships of pest grasshopper populations in Alberta, Canada to soil moisture and climate variables , 2007 .

[30]  S. Quiring,et al.  An evaluation of agricultural drought indices for the Canadian prairies , 2003 .

[31]  A. Barr,et al.  Evaluation of the Palmer Drought Index on the Canadian Prairies , 1996 .

[32]  Mary S. Lear,et al.  Spatial distribution of soil moisture over 6 and 30 cm depth, Mahurangi river catchment, New Zealand , 2003 .