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Nonlinear climate change and Andean feedbacks: an imminent turning point?

Bush, M. B.; Hanselman, J. A. and Gosling, W. D. (2010). Nonlinear climate change and Andean feedbacks: an imminent turning point? Global Change Biology, 16(12) pp. 3223–3232.

DOI (Digital Object Identifier) Link: http://dx.doi.org/10.1111/j.1365-2486.2010.02203.x
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Abstract

A 370 000-year paleoecological record from Lake Titicaca provides a detailed record of past climate change in which interglacial periods are seen to have some elements of commonality, but also some key differences. We advance a conceptual feedback model to account for the observed changes that includes previously ignored lake effects. Today Lake Titicaca serves to warm the local environment by about 4–5 °C and also to increase rainfall. We observe that as water levels in the lake are drawn down due to warm, dry, interglacial conditions, there is a possible regional cooling as the lake effect on local microclimates diminishes. Positive feedback mechanisms promote drying until much of the lake basin is reduced to salt marsh. Consequently, the usual concept of upslope migration of species with warming would not be applicable in the Altiplano. If, as projected, the next century brings warmer and drier conditions than those of today, a tipping point appears to exist within ca. 1–2 °C of current temperatures, where the relatively benign agricultural conditions of the northern Altiplano would be replaced by inhospitable arid climates. Such a change would have profound implications for the citizens of the Bolivian capital, La Paz.

Item Type: Journal Article
Copyright Holders: 2010 Blackwell Publishing Ltd
ISSN: 1354-1013
Keywords: aridity; charcoal; conservation; fossil pollen; grayscale; Lake Titicaca; positive feedback; warming
Academic Unit/Department: Science > Environment, Earth and Ecosystems
Interdisciplinary Research Centre: OpenSpace Research Centre (OSRC)
Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 25981
Depositing User: William Gosling
Date Deposited: 07 Jan 2011 11:35
Last Modified: 16 Nov 2012 16:37
URI: http://oro.open.ac.uk/id/eprint/25981
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