Climate change is enforcing physiological changes in Arctic ecosystems

Abstract Remote sensing and site-level observations have shown unprecedented changes in Arctic ecosystems owing to climate warming. These include greening browning trends vegetation as well species composition both the tundra boreal forests. Here, we leveraged solar induced chlorophyll fluorescence (SIF) study ecosystem phenology across pan-Arctic domain from 2000–2020. Ecoregions, a proxy for plants’ functional traits, were single most important variable explain spatial phenological heterogeneity observed SIF trends. We unique regional responses change affecting timing of spring photosynthesis onset, magnitude peak productivity during growing season fall senescence. While, Photosynthetic activity early showed increasing vast majority pan-Arctic, it tends decline at end nearly half land area, including parts North America but more significantly central Siberia. The highlight role biodiversity sensitivity emphasizes need better representations sub-biomes community level information process models projections. results also importance understanding carbon uptake towards predicting dynamics arctic with accelerated climate.