Focus 2 - Theme: Reconstruction Methods

Climate reconstructions from different methods and proxy datasets over the last millennia show general similarity in their depiction of large-scale mean temperature evolution, particularly at the decadal- to centennial timescale (Mann et al. 2008). There are, however, important differences at the interannual and multi-centennial- to millennial scale. It is unclear how much these differences result from the selection of specific proxy datasets, the potential inability of proxies to resolve information at all timescales, or from the algorithms themselves (National Research Council Report 2006).

A better understanding of strengths and weaknesses of reconstruction procedures is essential and will reduce uncertainties and potential biases, ultimately leading to a more accurate knowledge about the past climate. More detailed climate field reconstructions will provide this crucial understanding and substantially benefit studies of future climate, particularly those focusing on the regional level targeted within PAGES Focus 2. Reconstruction methods developed for the last millennia may ultimately be employed also on longer timescales during the Holocene and the last glacial cycle.

Working Groups

> CLIVAR/PAGES Intersection





Mann, M.E., Zhang, Z., Hughes, M.K., Bradley, R.S., Miller, S.K., Rutherford, S. and Ni, F., 2008: Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia, Proceedings of the National Academy of Sciences, 105: 13252–13257.
National Research Council, 2006: Surface Temperature Reconstructions for the Last 2,000 Years, The National Academy of Sciences: 160.