Environmental change on the 'Roof of the World': what do Tibetan lake sediment records tell us? Event
- Time:
- 16:00 - 17:00
- Date:
- 22 February 2012
- Venue:
- Building 44, Room 2103
Event details
The Tibetan Plateau including the Himalayas is the most topographically imposing feature on Earth and is inextricably linked to Asian climatic, hydrological and ecological systems. Furthermore, perturbations in the environment of the Tibetan Plateau have a profound effect on global climate as the plateau acts as an atmospheric nexus between the tropics and higher latitudes.
http://www.aber.ac.uk/en/iges/staff/academic-staff/andrew.henderson/
As a result, it has the potential to influence the large‐scale atmospheric circulation of the monsoon over Asia, and more widely over the northern Hemisphere, but it is itself sensitive to climate change. Some palaeoclimate records indicate the Asian monsoon does not always respond linearly to climate change. The main driver of large‐scale monsoon changes over the Holocene is the slow decrease in summer insolation as a result of changes in Earth's orbit. Superimposed on this trend, monsoon records show abundant evidence for abrupt, stepwise changes on timescales of a century and shorter. The mechanisms behind this behaviour are currently poorly understood with new records essential for documenting the degree to which abrupt changes are spatially and temporally coherent. As predictive models do not yet simulate the past abrupt changes in the Asian monsoon, they cannot be trusted to project such abrupt changes realistically in the future. In this talk I will present evidence for past changes in the monsoon system over a range of timescales from lake sediment archives from the Tibetan Plateau and discuss how they fit with the traditionally held view of the Asian monsoon system as whole.
Image: http://onorbit.com/node/3702