Spectral Compatibility of VIIRS Vegetation Index EDR with MODIS and AVHRR

Tomoaki Miura, University of Hawaii, tomoakim@hawaii.edu (Presenter)

Vegetation indices (VIs) are widely used in long-term measurements of vegetation changes and have become indispensable tools in climate, biogeochemical, and ecological studies. Two VIs, the “top-of-atmosphere (TOA)” normalized difference vegetation index (NDVI) and the atmospherically-corrected “top-of-canopy (TOC)” enhanced vegetation index (EVI), have been selected as an Environmental Data Record (EDR) to the Visible/Infrared Imager Radiometer Suite (VIIRS) sensor on the upcoming Joint Polar Satellite System (JPSS) and its preparatory project (NPP) missions. The development and provision of long-term data records require the effective integration of new sensor technologies and improved algorithms to better characterize global and climate change impacts on ecosystems. In the present study, we examined compatibility of the planned VIIRS VI EDR to the MODIS and AVHRR counterparts using a globally-distributed set of Hyperion scenes. Hyperion scenes were convolved to simulate VIIRS, MODIS, and AVHRR spectral bandpasses at 1 km spatial resolution. These convolved data were processed into TOA- and TOC-NDVI for VIIRS, MODIS, and AVHRR, TOC-EVI for VIIRS and MODIS, and TOC-EVI2 (a two-band version of EVI, without a blue band) for VIIRS, MODIS, and AVHRR, and compared to assess the impacts of differences in spectral bandpasses and atmospheric correction schemes on their cross-sensor compatibility. The highest compatibility were observed for VIIRS and MODIS NDVI of which relationship was nearly independent of atmospheric correction schemes, and for VIIRS and MODIS EVI2. The worst compatibility was observed for VIIRS TOA-NDVI vs. MODIS TOC-NDVI due primarily to different atmospheric correction schemes. VIIRS EVI was higher than MODIS EVI with their difference increasing non-linearly with index values, due primarily to disparities in their blue bandpasses. NDVI and EVI2 between VIIRS and AVHRR showed good compatibility, but their relationships were subject to large bias errors.

Presentation Type:  Poster

Session:  Other   (Wed 10:00 AM)

Associated Project(s): 

• Miura, Tomoaki: Evaluation and Validation of NPP VIIRS Vegetation Index EDR for Earth System and Climate Sciences ...details

Poster Location ID: 197