Sharpening Landsat 8 Thermal Imagery for Field Scale ET Mapping.

Thermal infrared (TIR) remote sensing provides valuable information for mapping land surface energy flux and evapotranspiration (ET). Landsat 8 carries a TIR instrument with two thermal bands that can provide a more accurate estimate of land surface temperature (LST) than its ancestors. However, the 100 meters spatial resolution of Landsat 8 TIR bands is not substantially superior to Landsat 5 (120m) and Landsat 7 (60m). For the ET mapping at the field scale, a finer resolution of TIR data like Landsat shortwave sensors (30 m) is required. Recently, we developed a data mining sharpener (DMS) approach to improve spatial resolution in LST retrievals. The DMS approach has been tested to sharpen thermal band imagery for Landsat 5 and Landsat 7. In this presentation, we extend the approach to the recently launched Landsat 8 data. We will demonstrate the sharpening results from Landsat 8 over landscapes that have different crop types and soil background. The potential for the DMS approach to be used operationally for Landsat 8 will be discussed. The ET estimation from both original and sharpened TIR imagery will be compared and analyzed.