APPLEx-2

Project Archive

Project Overview 

The overall objective of this project is to establish and evaluate a new national capability for microwave remote sensing in environmental research that will provide unprecedented information on soil moisture and allow for demonstrating a new satellite concept. Specifically, by combining different sensors, data can be collected at P- and L- band with approximately half the spatial resolution at P-band as for L-band at the same flying height. Apart from the airborne observations, simultaneous ground observations of soil moisture and ancillary data will be conducted for soil moisture retrieval. The APPLEx data sets will provide multi-temporal data to:

  • Evaluate soil moisture retrieval at 1km resolution using PPMR brightness temperature observations. 
  • Evaluate soil moisture retrieval at 1km resolution using combined PPMR/PLMR brightness temperature observations. 
  • Evaluate soil moisture retrieval at 100m resolution using PLIS or PPIS backscatter observations. 
  • Evaluate downscaling algorithms by integrating radar and radiometer observations at P- and/or L-band. 

Data collected during APPLEx-2 was mainly consist of: 

  • airborne P-/L- active and passive microwave observations, together with ancillary optical cameras; 
  • continuous near-surface (top 5 cm) soil moisture and soil temperature monitoring at 28 permanent stations within the flight area, with sensors at 5 cm depth increments to a depth of 25 cm and also at 40 cm. An additional 6 stations within the broader Yanco Study Area include profile (0-90 cm) soil moisture and soil temperature data; 
  • additional intensive measurements of near-surface (top 5 cm) and deeper (to 20 cm) soil moisture spatial variation, vegetation biomass, water content and reflectance, and surface roughness across four approximately 3 km × 3 km and 1 km x 1 km paddock to add an additional vegetation type. 

Location of the APPLEx-2 project

APPLEx-2 Group Photo 

Overview of Data Set 

An example from the APPLEx-2 campaign in October and November 2022.

PLEASE NOTE: The following data sets should be acknowledged According to the following:

APPLEx:

Walker, J. P., 2022.