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| Titel |
Trends in 20th Century Global Rainfall Interception as Simulated by a Dynamic Global Vegetation Model: Implications for Global Water Resources |
| VerfasserIn |
Steve Murray, Colin Prentice |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250040435
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| Zusammenfassung |
| In order to monitor and forecast regions of potential freshwater stress and surplus, a
comprehensive understanding and quantification of the global hydrological cycle and its
components is needed. Such work should lead to better constrained estimates of
freshwater fluxes and facilitate the identification of regions requiring enhanced water
management.
The research described here aims to quantify the contribution of climate- and
CO2-induced changes in the physical properties of the land surface, mediated by biological
processes. Global climate change is expected to bring about substantial latitudinal and
altitudinal shifts in vegetation cover. Shifts in species distribution, the potential of increased
leaf area index (LAI) but also reduced stomatal conductance in response to rising
concentrations of CO2, and variability in precipitation, can all influence rates and
spatial variability of the interception-throughfall balance. These effects will have
implications for runoff generation and the partitioning between ‘green’ and ‘white’ water
fluxes.
The Land Processes eXchange Dynamic Global Vegetation Model (LPX-DGVM, a
development of the LPJ model) was evaluated in terms of its interception component and
used to simulate trends in global relative throughfall from 1901-2006, as this is directly
relevant for runoff. We estimate that mean global annual runoff was reduced by 164 ±18
km3/year during the twentieth century as a result of biophysical changes controlling relative
throughfall generation. Widespread decreases in relative throughfall of typically between 0
and -1% are evident between 1901-1953 and 1954-2006. Changes of up to |
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