found in a variety of paleoenvironments (ocean, atmosphere, and land). Several potential causes for these events have been proposed, but without a more detailed understanding of the relative phasing of these events from region to region, definitive causal mechanisms cannot be constructed.

Of greatest consequence to humans is the fact that subdued versions of these events are documented during our current interglacial (the Holocene, which began ~11,500 years agoa). While subdued relative to earlier events, they are still sufficient to significantly perturb natural systems and still operate at rapid rates (years to decades). Thus, one of the most important tasks for paleoclimatologists is to improve our understanding of Holocene climate, for it is within the Holocene that the boundary conditions for modern natural climate variability can be identified and from which the relative importance of natural versus anthropogenic climate forcing can be assessed.

Patterns in climate variability can be identified on the interannual to millennial scale. This finding is particularly encouraging since one of the end goals of climate change research is predictability. However, deconvolving predictable patterns at the regional scale and determining the temporal baseline from which predictability can be assessed will require more dense spacing of paleodata.

Few instrumental records precede the era of anthropogenic involvement; thus, it is necessary to supplement and hindcast these data with paleoclimate records. The intended meaning of hindcast is to extend instrumental time series back prior to their onset date using proxy records. The assumption is made that a transfer function of some type links the instrumental and proxy records allowing this process. Fortunately, many paleodata series afford detailed views of pertinent climate indicators (e.g., temperature, precipitation, El Niño-Southern Oscillation (ENSO), monsoon). On the other hand, since there are no true analogs in the paleoclimate record for modern or future climate, it is essential to utilize both modern observational and paleoclimate records to solve this complex problem.

New advances in paleoclimate research reaffirm the necessity to view climate change over varying timescales; utilize a variety of globally distributed paleoclimate records that monitor change throughout the Earth system; and focus attention on well-dated, highly resolved multivariate paleoclimate records. These paleodata are essential for understanding global environmental change and its potential impact on humans, assessing human influence on the global environment and for the evaluation of predictive climate models.

The research imperatives for paleoclimate are to:

  • Document how the global climate and the Earth's environment have changed in the past and determine the factors that caused these changes. Explore how this knowledge can be applied to understand future climate and environmental change.

a

Assumed format is calendar years unless specified as 14C years.



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