GEOPHYSICAL MONOGRAPH SERIES, VOL. 193, PP. 215-233, 2011
Abrupt Climate Change: A Paleoclimate Perspective From the World's Highest Mountains
Ice core records recovered from high-elevation, low-latitude ice fields, along with other proxy data, provide two primary
lines of evidence for past and present abrupt climate change. First, there is strong evidence from paleoclimate records from
within and around these glaciers for two widespread and spatially coherent abrupt events during the Holocene: a major isotopic
excursion centered on ∼5.2 ka B.P. marks the transition from early Holocene warmth to cooler conditions, and a major dust
increase occurs between 4.0 and 4.5 ka B.P. Both of these events were concurrent with structural changes in early civilizations.
Second, the continuing retreat of most midlatitude to low-latitude glaciers, many having persisted for millennia, signals
a recent and abrupt change in Earth's climate system. High-resolution ice core stratigraphic records of δ18O (temperature proxy) demonstrate that the current warming at high elevations in the middle to lower latitudes is unprecedented
for at least the last two millennia, even though they suggest that the early Holocene was much warmer at many sites. The remarkable
similarity between changes in the highland and coastal cultures of Peru and climate variability, especially with regard to
precipitation, implies a strong connection between prehistoric human activities and climate in this region. Well-documented
ice loss on Quelccaya in the Andes, Naimona'nyi in the Himalayas, and Kilimanjaro in eastern Africa paint a grim future for
recovery of tropical glacier histories. The current melting of high-altitude, low-latitude ice fields is consistent with model
predictions for a vertical amplification of temperature in the tropics.
Citation: Thompson, L. G. (2011), Abrupt climate change: A paleoclimate perspective from the world's highest mountains, in Abrupt Climate Change: Mechanisms, Patterns, and Impacts, Geophys. Monogr. Ser., vol. 193, edited by