Natural archives

Natural archives Tree-rings, peat bogs, sea- and... 

Keywords Air pollution, Alpine glaciers, Climate reconstruction, Ice core, Natural archives... 

However, in the Alps there are only a few glaciers suitable as natural archives. A prerequisite is that fim temperatures are well below 0°C and melt-water percolation is negligible in order to preserve the signal of past climate and environmental changes. Such conditions can be found above 4,000 m a.s.l. in the Northern part and above 4,300 m a.s.l. in the Southern part of the Alps [3]. Thus, potential sites for obtaining useful samples are limited to a few high-elevation areas, for instance the Bernese Alps, the Monte Rosa area, and the Mont Blanc area. 

Isotopic reconstruction of climatic conditions on the continents is difficult, because land ecosystems and climates exhibit great spatial and temporal heterogeneity. The most readily determined terrestrial climatic parameter is the isotopic composition of precipitation, which is in turn dependent largely but not exclusively on temperature. Relevant climatic information from meteoric precipitation is preserved in a variety of natural archives, such as (1) tree rings, (2) organic matter and (3) hydroxylbearing minerals. 

Seabird feathers may provide a proxy for oceanic mercury secular change (Monteiro and Furness, 1997). This unique dataset includes feathers retrieved from museum specimens of exclusively pelagic, piscivorous seabirds such as shearwaters and petrels. While there is scatter associated with the values, as should be expected from such a natural archive, an increase of —3 X between 1885 and 1994 can be seen in the mercury concentration of the feathers. Furness, Monteiro and co-workers have extended their work to include studies on the movement of mercury within hving birds and the relationship between prey concentrations of mercury and those observed in the bird s feathers (Monteiro et al., 1998 Monteiro and Furness, 2001), which aid in the interpretation of the feather record. This approach has so far been apphed to the NE... 

In a review focused on the findings of his team over the years, Heumann stressed the role of Antarctica as the natural archive of past events on the planet and highlighted the fact that the very sampling process may be a significant source of contamination of the materials collected due to their extremely low contents in... 

Thus, explanation of the ice-core records demands a creative interaction with other fields of earth system science. We identify two such fields as crucial. The first is global modeling, which is a standard approach to climate change problems (both present / future and past) and is being actively extended to include interactions of the biogeochemical cycles with climate. The second is Quaternary science in the broad sense, especially insofar as Quaternary paleo-environmental records have been standardized and compiled on a global scale. Quaternary scientists have amassed data from widely distributed natural archives such as marine and lacustrine sediments which, when suitably compiled, yield spatially extensive information about many aspects of climate, ecosystem composition, and even some indicators of atmospheric composition such as the... 

In conclusion, by insisting that the model results are routinely tested against the full spectrum of available palaeodata (from ice cores and other natural archives), we suggest that the study of past biogeochemical cycles can provide both a unique means to test complex earth system models and a powerful stimulus to their further development. 

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