Understanding the controls of the greening of terrestrial vegetation of northern Eurasia.

Pawlok Dass, University of Massachusetts Amherst, pawlokdass@geo.umass.edu (Presenter)
Michael Rawlins, University of Massachusetts, Amherst, rawlins@geo.umass.edu
Youngwook Kim, University of Montana-NTSG/FLBS, youngwook.kim@ntsg.umt.edu
John S Kimball, University of Montana, johnk@ntsg.umt.edu

Terrestrial ecosystems of northern Eurasia are greening, yet few studies have provided definitive attribution for this trend. While prior studies point to increasing temperatures as the principle driver, influences from moisture and other environmental drivers are more unclear. We assess how changes in temperature, precipitation, cloudiness and forest fires contribute to the observed changes in Gross Primary Productivity (GPP) across northern Eurasia. Observational data spanning the period 1982 - 2008 are examined. Our results confirm prior studies which have suggested that air temperature is the dominant driver of GPP trends across this region. Annual temperature explains up to 30% of the variation in GPP while other environmental drivers explain less than 20%. Each driver influences productivity most strongly during summer, i.e. the peak of the growing season. Warming over the period examined, even without a sustained increase in precipitation has lead to a productivity increase of 72% and 74% for the GIMMS and VIP GPP datasets respectively. On the other hand, productivity decreased across 2% and 4% of this region for the respective datasets, primarily over the dryer grasslands in the south-western part of the region. For this area, precipitation positively correlates with GPP, as does cloudiness, showing that while most of northern Eurasia is resilient, the south-western part is vulnerable to drought stress.

Presentation: 2015_Poster_Dass_41_79.pdf (1573k)

Presentation Type:  Poster

Session:  Theme 4: Human influence on global ecosystems   (Mon 4:30 PM)

Associated Project(s): 

• Rawlins, Michael: Synthesis and Integration of Recent Research Characterizing the Carbon Cycle of Northern Eurasia ...details

Poster Location ID: 41