Reports of increased tree mortality and forest decline due to climate extremes have been accumulating during past decades, raising concerns about forest health under ongoing climate change. Currently, there is no coherent and systematic assessment of trends and patterns in global tree mortality. Existing forest inventory (FI) data are often not openly accessible and/or the underlying sampling protocols vary among countries and make merging of databases difficult.
While the spatial resolution in ground-based data is good to detect tree mortality, the temporal resolution of FI is often poor and grid density low. Remote-sensing (RS) products, on the other hand, provide a better spatial coverage but the resolution is often too low to detect mortality of individual trees. Our task force aims to facilitate merging of existing FI databases that can become a ground-truthing tool for RS approaches, where FI provides the fine-scale information that is integrated over larger scales with RS. We aim to stimulate/catalyze international cooperation in order to detect changes in tree mortality patterns and taken as indicator for forest health.
In this presentation, we describe our approach and explain the concepts. We also highlight the achieved progress during the last few years. We will give an oral presentation interspersed with short interviews.