LDEO's Joerg Schaefer Explores Santiago's Water Crisis as Scholar in Residence
During his stay, he engaged with academics, students and key stakeholders like policymakers, legal experts and urban planners.
Joerg Schaefer, distinguished Lamont Research Professor and founding Director of the Cosmogenic Nuclide Group at the Lamont-Doherty Earth Observatory (LDEO), was the first of four Scholars in Residence selected by Columbia Global for a research stay in Santiago during 2025. Over the course of his stay in March, Schaefer leveraged a decade of collaboration with Chilean colleagues to advance understanding of how glacier retreat and climate change threaten water security in high‑altitude megacities.
As an adjunct professor in Columbia’s Department of Earth and Environmental Sciences and a senior fellow at the Center for Climate and Life, Schaefer has dedicated his academic career to understanding the response of glaciers and ice sheets to past and present warming. His research focuses on the impacts of ice-related hazards—such as tsunamis and glacial lake outburst floods—and the critical role of science in addressing these pressing environmental challenges.
In addition to his research and teaching roles, Schaefer co-directs Columbia Earth Networks’ “Decarbonization, Climate Resilience, and Justice” initiative, co-leads the undergraduate program in Sustainable Development, and serves as a Research Professor in Geochemistry at the Columbia Climate School.
A Mission to Address the Santiago Water Crisis
Schaefer’s residency in Santiago centered on a project inspired by a growing environmental and societal crisis: the rapidly intensifying water scarcity in high-altitude megacities that depend on snow and glacier melt, including Santiago, Bogotá, Lima, and Quito. His initiative built upon more than a decade of collaboration with Chilean geologist Esteban Sagredo, professor at Universidad Católica’s (UC) Institute of Geography, and Rodrigo Soteres, Postdoctoral Researcher at Universidad de Magallanes’ (UMAG) Centro de Investigación GAIA Antártica, with whom he has worked on the impacts of climate change on mountain environments and their implications for water availability and quality.
Schaefer’s Scholar‑in‑Residence project, “The Santiago Water Crisis,” aimed to advance a multi-pronged effort that included scientific research, policy dialogue, and the design of new educational programs for Columbia students. Key objectives of the residency were to hold public events and establish connections with local policymakers and stakeholders. The initiative also envisioned the creation of a field-based educational program for Columbia students, anchored in Santiago and Magallanes, to study ice melt and water management challenges in the Andes.
Apart from his long-standing partnership with colleagues at UC’s Department of Geography and UMAG, and a strong support network through the Santiago Center, Schaefer selected Santiago for this initiative due to its rapidly retreating glacier catchment, El Manzano; its growing urban population; and the increasing pressure from large-scale agricultural industries such as wine and avocado production.
“The future of these megacities literally dries up in our warming world, and the current scientific understanding of past, modern, and future ice melt—and thus dry‑season water supply—remains under‑constrained. It is our duty as scientists, educators, and citizens to invest more effort into improving the robustness of our predictions and the solutions we propose,” he assures.
Engaging with Chilean Institutions and the Public
Schaefer’s time in Santiago included a series of public events and meetings designed to foster interdisciplinary dialogue and strengthen local partnerships. On March 20, he delivered the lecture “Dialogues with Geography: Climate and Ice – From Rising Seas to the Mountain Water Crisis,” co-sponsored by the UC Institute of Geography, LDEO, and the Santiago Center. Held at the auditorium of UC’s School of History, Geography, and Political Science, the event was filled to capacity with students. The talk focused on the impact of global warming on glaciers, water systems, and sea level rise. Schaefer warned: “If rising temperatures linked to climate change are not curbed, by 2100, 80% of glaciers will have disappeared.”
On March 24, the UC Institute of Geography hosted a screening of “The Memory of Darkness, Light, and Ice,” a 2024 documentary directed by evolutionary biologist and documentary filmmaker Kathy Kasic. The 50-minute documentary features striking scientific discoveries on the vulnerability of the Greenland Ice Sheet by researchers including Schaefer and Columbia professor Dorothy Peteet. The film reflects on the importance of learning from the past to confront the future, as it states: “Our ability to look forward is strengthened by looking back.”
On March 27, the Santiago Center organized a working lunch with Schaefer and Rebecca Gustine, a Postdoctoral Research Scientist at LDEO, joined by key Chilean collaborators. The meeting included Schaefer’s long-time research partner Esteban Sagredo; Robert Currie (LAW’13), a Chilean environmental lawyer who helped draft Chile’s 2022 Climate Change Framework Law; and Nicolás Díaz, a specialist in architecture and urban studies, who addressed the growing demand for fresh water to cool data centers in Latin America and the risks posed by their unregulated use of wetland resources in Chile. The group discussed glacier retreat and water use in Chile from legal, scientific, and urban planning perspectives. Schaefer emphasized that while the evidence of climate-driven glacial melt has been clear for years, scientists must now collaborate more deeply with policymakers, legal experts, and urban planners to co-create sustainable solutions.
Schaefer’s research stay also laid the groundwork for a future Columbia University field program in Patagonia, including a partnership with the Patagonian Icefields Research Program co-directed by Rodrigo Soteres.