Collaborative Research: Pattern and Timing of Full-Glacial Conditions in the Southern Hemisphere

New evidence shows that some environmental changes, such as the end of the last ice age, happened so fast that they are difficult to attribute to a direct cause. This project explores the possibility that such abrupt changes are underpinned by tipping points, perhaps with little direct or specific trigger. If the ocean and atmosphere system are found to behave in this manner, it would require substantial modifications to current models upon which society relies to estimate longer term changes in Earth’s surface environment. This is of significant importance because of the enormous effect the environment has on society, including agriculture, health, national security, and coastal planning among other things. This project also contributes to workforce development and public education through the involvement of students and outreach activities. Traditional explanations for abrupt environmental change are deterministic with a specific cause or mechanism leading to a largely predictable result. However, recent evidence suggests that some abrupt environmental changes are so fast that they have tipping points. This project examines whether Earth’s environment during the last ice age shows characteristics of a nearly intransitive system with rapid jumps between two or more semi-stable states. The research will 1) synthesize existing records of environmental change in the southern hemisphere covering the descent into and jump out of the ice age; 2) develop new records of environmental change (glacial, geochemical and sedimentological proxies from lake and periglacial deposits) from a key Southern Hemisphere location, the Falkland Islands, and 3) model the drivers of Earth system change over this period using the synthesis and new data as metrics for an Earth System model. This information will be used to test whether the patterns and rates of environmental change are consistent with a nearly intransitive system. Broader impacts include the training of students for the workforce of the future and public outreach through the production and distribution of an educational brochure. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.