Overview
Dr. Jonathan “Johnny” Ryan is a glaciologist who is interested in ice sheet surface processes. His research has investigated several key components that influence the accumulation and ablation of ice sheets, including snowfall, clouds, melt-albedo feedbacks, and supraglacial hydrology. To conduct this research, Johnny primarily relies on satellite remote sensing. This expertise has earned him selection onto NASA’s ICESat-2 and Terra/Aqua/Suomi Science Teams. Johnny also conducts field research and has spent many summers surveying ice sheets and glaciers with uncrewed aerial systems (UAS) or drones. His primary research site is the Greenland Ice Sheet, where he has worked out of Kangerlussuaq and Uummannaq. He has also conducted research on the Northern Patagonia Icefield and the Oregon Cascades. By combining fieldwork with new satellite remote sensing technology, Johnny’s research bridges spatial and temporal scales to generate new insights into ice sheet surface processes. The significance of his research is reflected by recent first- and second-author publications in journals such as Nature, Environmental Research Letters, Science Advances, Nature Communications, and Geophysical Research Letters.
Current Appointments & Affiliations
Recent Publications
Contribution of surface and cloud radiative feedbacks to Greenland Ice Sheet meltwater production during 2002–2023
Journal Article Communications Earth and Environment · December 1, 2024 Greenland Ice Sheet meltwater runoff projections are essential for accurate forecasts of global sea-level rise. However, melt depends on complex interactions between climate warming, surface albedo, and clouds, which are challenging to simulate in models. ... Full text CiteRetreat of the Greenland Ice Sheet leads to divergent patterns of reconfiguration at its freshwater and tidewater margins
Journal Article Journal of Glaciology · September 16, 2024 Greenland's marine- and land-terminating glaciers are retreating inland due to climate warming, reconfiguring the way the ice sheet interacts with its proglacial environment. Here we use three decades of satellite imagery to determine whether the ice-sheet ... Full text CiteCommunity-scale changes to landfast ice along the coast of Alaska over 2000-2022
Journal Article Environmental Research Letters · February 1, 2024 Landfast sea ice that forms along the Arctic coastline is of great importance to coastal Alaskan communities. It provides a stable platform for transportation and traditional activities, protects the coastline from erosion, and serves as a critical habitat ... Full text Open Access CiteRecent Grants
Retrieval of glacier ice and snow properties over the Greenland Ice Sheet from ICESat-2
ResearchPrincipal Investigator · Awarded by National Aeronautics and Space Administration · 2025 - 2027View All Grants