The following HTML text is provided to enhance online
readability. Many aspects of typography translate only awkwardly to HTML.
Please use the page image
as the authoritative form to ensure accuracy.
between one-third and one-half of terrestrial biological
production is used or dominated by human action (Vitousek et al.,
1997), and human-induced land-use changes are difficult to
anticipate, the prediction of future vegetation distributions is a
difficult undertaking. However, even in the absence of local-scale
ecosystem forecasting skill, there is value in assessing the
large-scale response of modeled ecosystems to uninitialized
climate-model forecasts. Such models can be used to assess the
future, large-scale response of terrestrial carbon sinks to altered
climate or to anthropogenic inputs, for instance, or the effects of
large-scale, vegetation-related albedo or surface roughness changes
on climate. As longer time series of the relevant vegetation data
become available for testing ecosystem-climate models, and these
models are more rigorously validated and improved, the value of
their forecasts will increase, particularly to the societies and
institutions that depend most directly on ecosystems.