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Chapter 06
In the second approach, TiP considers three different time scales (Fig. 3) overlapping with each other, and affecting each other from long-term to short-term. The phase of plateau formation is the longest-term scale involving the last several ten millions to millions of years during which uplift and related climate. change are the outstanding research topics. Change of environmental conditions forced the development and diversification of specifically adapted ecosystems. Reconstruction of temporal and spatial uplift history requires understanding of plateau formation processes. Proxy data for palaeoelevation may contribute more direct information. The Late Cenozoic climate evolution and environmental response deals with a system where the Tibetan Plateau had approximately been at its present elevation and had reached its current spatial extent, forming boundary conditions for climate and ecosystem development. During this phase, neotectonic activity has been an important factor and monsoon dynamics developed into a significant driving force shaping the landscape especially during glacial/interglacial cycles. The third and shortest time scale is the phase of human impact and Global Change. When humans became part of the ecosystems some 8,000 years ago, a new quality of interactions and feedbacks became apparent. Understanding the human impact on the different ecosystems and on the water cycle with the potential future consequences requires knowledge on the specific evolution of the entire geo-biosphere system including humans themselves, related to all the time scales considered in TiP.
Time Scales
... human impact and Global Change
10 10
... Late Cenozoic
climate evolution
10
of...
10 10
Climate and Study of Glaciers
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climate evolution
human impact
ecosystems
plateau formation
Fig.2: Interaction of the three forcing mechanisms of TiP, Plateau formation, climate evolution, human impact, and their effects on ecosystems.
plateau formation
10* 10' 10"
years
Fig. 3: The three time scales of TiP; peaks characterise time periods of highest impact
The subsequent science plan is subdivided into the three time scales shown in Fig.3. 3.1 Plateau formation and environmental impacts
Tip aims to reveal the impact of plateau formation on climate and ecosystems on a time-scale of millions to several tens of millions of years. The plateau formation will be deduced from geodynamic processes and proxies of elevation history. TiP will use lacustrine and terrestrial archives to reconstruct the palaeo-environmental evolution and relate these results to the evolution of the plateau.
Tibetan Plateau: Formation-Climate-Ecosystems
