In southern Africa, recent work has established and refined the potential of rock hyrax middens (accumulations of urine and faecal pellets) as stratified, continuous paleoenvironmental archives containing a range of climate and vegetation proxies (Chase et al., 2009; Gil-Romera et al., 2007; Meadows et al., 2010; Scott and Woodborne, 2007).
Africa2k was part of the 2k Network under PAGES' Focus 2: Regional Climate Dynamics - Last two millennia. It was established in Corvallis, Oregon, USA, at the PAGES YSM/OSM meeting on 7 July 2009.
It is known that Africa is vulnerable to climate change, mainly through impacts on precipitation and through changes in the frequency and magnitude of climate extremes. This vulnerability is linked to widespread poverty, mismanagement of natural resources, conflicts and dependence on rain-fed agriculture.
Assessments of climate variability in Africa are difficult due to the sparse spatial coverage and often short time span of available instrumental records, and the prevalence of semi- to hyper-arid environments in the extra-equatorial regions over the last two millennia. These dry climates have generally precluded the long-term existence of lakes and wetlands, which in temperate and tropical regions typically preserve long records of environmental change. The result is a regional dataset characterized by spatially disjunctive, temporally discontinuous records, often with unreliable chronological control and ambiguous palaeoenvironmental significance.
Considering the facts above and the potential impacts of future climate change, Africa2k aimed to:
1. Conduct an audit of existing palaeoenvironmental archives, compile and evaluate the significance of published material
2. Collate these data to construct a pan-African synthesis of climate change spanning the last 2 kyr, and
3. Use this synthesis to identify key areas for future work, including new archives that can provide reliable palaeoenvironmental information at annual to multi-decadal time scales. This will provide a basis for direct comparisons with general circulation model simulations (GCMs), and for assessing the range of natural climate variability within which humans and ecosystems have been operating effectively, and the extent to which climates may exceed this envelope under potential future scenarios.