US EPA

1605417 

Journal Article 

Risk of severe climate change impact on the terrestrial biosphere 

Heyder, U; Schaphoff, S; Gerten, D; Lucht, W 

2011 

1 

Environmental Research Letters
ISSN: 1748-9326 

6 

3 

034036 

10.1088/1748-9326/6/3/034036 

WOS:000295327900039 

http://stacks.iop.org/1748-9326/6/i=3/a=034036?key=crossref.69e02a2ee8b7b3fe4230432a8b696a37
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The functioning of many ecosystems and their associated
resilience could become severely compromised by climate change over the 21st century. We present
a global risk analysis of terrestrial ecosystem changes based on an aggregate metric of joint
changes in macroscopic ecosystem features including vegetation structure as well as carbon and
water fluxes and stores. We apply this metric to global ecosystem simulations with a dynamic
global vegetation model (LPJmL) under 58 WCRP CMIP3 climate change projections. Given the current
knowledge of ecosystem processes and projected climate change patterns, we find that severe
ecosystem changes cannot be excluded on any continent. They are likely to occur (in >90% of the
climate projections) in the boreal-temperate ecotone where heat and drought stress might lead to
large-scale forest die-back, along boreal and mountainous tree lines where the temperature
limitation will be alleviated, and in water-limited ecosystems where elevated atmospheric CO(2)
concentration will lead to increased water use efficiency of photosynthesis. Considerable
ecosystem changes can be expected above 3 K local temperature change in cold and tropical
climates and above 4 K in the temperate zone. Sensitivity to temperature change increases with
decreasing precipitation in tropical and temperate ecosystems. In summary, there is a risk of
substantial restructuring of the global land biosphere on current trajectories of climate
change. 

ecosystem change; DGVM; climate change; impact metric