Climate Change in Eurasia: Perspectives over Space and Time

Abstract

A prominent physical geographer offers a brief primer on climate change in general and then brings spatial and temporal perspectives to bear in an assessment of the past, present, and future changes of climate over Eurasia. More specifically, he addresses climate change and feedbacks for Eurasia over longer (tectonic forcing, >105 years), intermediate (Earth's orbital relations, 104-105 years), and shorter timeframes (<104 years), emphasizing that climates change more or less continuously in response to many forcing factors (solar output, Earth's eccentric orbit, rotational tilt, precession, and interactive atmosphere-ocean-land systems, including human impacts). Although these factors operate at different rates and timescales, they may coincide at times to promote rapid change. The nesting of the current, three-decade pattern of warming within longer centennial- and millennial-scale cycles of warming and cooling since the Holocene Optimum (itself a warm interglacial stage within warm and cold cycles in the late Cenozoic over the last 50 million years) shows that the recent rapid warming since 1980 is not unique in Earth history, although it does warrant concern and raises questions of global significance.