Understanding Earth's Deep Past: Lessons for Our Climate Future

摘要

The drive to better understand how Earth's climate has responded to natural and anthropogenic forcing over the geologically recent past has resulted in a plethora of observational and modeling paleoclimate studies seeking to understand climate dynamics associated with glacial and interglacial cyclicity. From these near-time paleoclimate studies the scientific community has developed a refined understanding of the complex--and often nonlinear--dynamics of the Earth's climate system and has delineated an array of environmental and ecological impacts that have accompanied climate change over the past few thousands to hundreds of thousands of years. The knowledge gleaned from this near-time archive has been of great importance for predicting Earth's immediate future climate. There is, however, a growing appreciation by the scientific community that the changes observed over the past few decades may lead to a degree of warming and associated climate, resource, and ecological changes well beyond those of the icehouse climate state in which humans evolved and currently live. Critical insights to understanding such changes are contained in the deep-time geological record that captures the response of the climate system to the full spectrum of internal and external forcings, and their feedbacks, experienced over Earth history.