Vegetation presents a key feature in our climate system as it affects both water and carbon cycle. Characterising large-scale vegetation dynamics can contribute to understanding complex interactions between plants and their abiotic resources. Monitoring vegetation using microwave satellite observations provides complementary information to the commonly used optical data due to the higher penetration depth of microwave radiation and their sensitivity to the vegetation water content. Therefore, microwave Vegetation Optical Depth (VOD) can be used to analyse water related processes governing vegetation growth. VOD is available from active and passive sensors and from different frequencies in the microwave domain, for vegetation monitoring most notably L-, C-, X-, and Ku-band. The sensitivity of VOD to the vegetation cover varies with frequency and sensor type. Thus, a comparison of multiple VOD datasets with respect to the targeted vegetation properties is necessary to make full use of microwave satellite observations for describing large-scale ecosystem dynamics.
Mean Ku-band VOD [unitless] 2002.06 - 2017.06 (click to enlarge)
Recently CLIMERS estimated the Gross Primary Production (GPP) using VOD data, and created the VOD Climate Archive (VODCA), a global VOD dataset spanning the last 30 years that is openly accessible on Zenodo.