In Fall of 2015, the SLAP instrument was deployed to Winnipeg, Manitoba, Canada to collect data for freeze/thaw algorithm evaluation. Thirteen science flights were flown over a target area southwest of Winnipeg, MB, coincident with the study area used in SMAPVEX12.
A ground team consisting of members from NASA Goddard Space Flight Center, Agriculture Canada, Environment Canada, University of Guelph, George Mason University, and City University of New York collected in situ measurements while the SLAP instrument collected airborne data from the NASA Langley Research Center King Air B-200 aircraft. Pilot support was also provided by NASA Glenn Research Center.
Five lines were flown each flight to correspond with ground truth sample locations and each day two flights were conducted in frozen (AM) and thawed (PM) conditions.
Two additional "mow-the-lawn" (MTL) flights were flown to obtain full coverage of a 36x36 km SMAP pixel, the first in thawed and then the second in frozen conditions.
For more information on the ground truth sites, consult this presentation which includes field numbering and aerial photographs of the conditions.
The following table contains SLAP radiometer data that has been processed and calibrated and is provided in the following formats: