HR: 11:05h
AN: PP52A-04 INVITED     [Abstracts]
TI: Advancing Into the Past: How Proxies and Models Explore Climate Before the Instrumental Record.
AU: * Ammann, C M
EM: ammann@ucar.edu
AF: Climate and Global Dynamics Division National Center for Atmospheric Research, 1850 Table Mesa Drive, Boulder, CO 80305 United States
AB: In recent years, advances in extracting information from the various high-resolution (annual or seasonal) paleo archives around the world have continued to extend our record of climate. Many of these records allow us to analyze and interpret not only the mean state, but also the variability in the climate system and how it changed over time. With this shift in focus comes the potential to evaluate aspects of climate variations from a more regional perspective and, thus, the records gain in relevance for decision makers involved with environmental issues. Coupled Ocean-Atmosphere Climate System Models have propelled our understanding of numerous aspects of the Earth's climate system. Using histories of external forcing factors (such as volcanic eruptions and solar activity changes), models are capable of reproducing significant parts of past climate variations on a variety of time scales. Coupled climate models can provide us with physical concepts of how certain patterns of past climate changes might have developed. It is well known that the instrumental record is too short to sample the full range of natural variations and an extension using high-resolution proxies is very valuable. Additionally, models are essential tools to study mechanisms of how climate is responding to various forcing agents. Through close comparison of long histories as reconstructed from proxies with long transient simulations forced with best estimates of external agents such as explosive volcanism, solar activity changes as well as human induced changes to the atmospheric composition or the land surface, we can not only extend the record of climate and its variations back in time, but we can also use the `power of history' to calibrate assessments of future climate changes.
DE: 7538 Solar irradiance
DE: 3344 Paleoclimatology
DE: 3210 Modeling
DE: 1600 GLOBAL CHANGE (New category)
DE: 1620 Climate dynamics (3309)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting