Early snowmelt significantly enhances boreal springtime carbon uptake
Research output: Contribution to journal › Article
We determine the annual timing of spring recovery from spaceborne microwave radiometer observations across northern hemisphere boreal evergreen forests for 1979–2014. We find a trend of advanced spring recovery of carbon uptake for this period, with a total average shift of 8.1 d (2.3 d/decade). We use this trend to estimate the corresponding changes in gross primary production (GPP) by applying in situ carbon flux observations. Micrometeoro-logical CO2 measurements at four sites in northern Europe and North America indicate that such an advance in spring recovery would have increased the January–June GPP sum by 29 g·C·m−2 [8.4 g·C·m−2 (3.7%)/decade]. We find this sensitivity of the measured springtime GPP to the spring recovery to be in accordance with the corresponding sensitivity derived from simulations with a land ecosystem model coupled to a global circulation model. The model-predicted increase in springtime cumulative GPP was 0.035 Pg/decade [15.5 g·C·m−2 (6.8%)/decade] for Eurasian forests and 0.017 Pg/decade for forests in North America [9.8 g·C·m−2 (4.4%)/decade]. This change in the springtime sum of GPP related to the timing of spring snowmelt is quantified here for boreal evergreen forests.
|Research areas and keywords||
Subject classification (UKÄ) – MANDATORY
|Number of pages||6|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|Publication status||Published - 2017 Oct 17|