Seminars and Colloquia
Earth and Climate Science
Monitoring glacier changes using space-borne radar remote sensing
Thu, Aug 06, 2020,
03:30 PM
at Webinar
Dr. Saurabh Vijay
Byrd Polar & Climate Research Center, The Ohio State University.
Our planet Earth is dynamic in nature. There takes place a number of dynamic processes on Earth such as glacier ice flow, crustal movements, and volcanic eruptions. Although field experiments are important to study these processes, they have limitations related to the accessibility of study sites and the continuity of observations. Over the years, remote sensing has emerged as an alternative tool potentially closing the gaps of field-based observations. So far, I primarily pursued my academic research on glacier changes using satellite remote sensing techniques. There are two fundamental questions which I sought the answers for:
i) How do glaciers change (ice dynamics and mass change) over seasonal to decadal time scales?
ii) What are the external (e.g. atmosphere, ocean) and system inherent factors (e.g. topography) that govern these changes?
In this talk I will show two case studies: mountain glaciers of the Indian Himalaya-Karakoram region and ocean-terminating glaciers of Greenland. In the first case study, I will show glacier mass change rates of more than 3700 glaciers located in Himachal Pradesh, J&K and Ladakh regions during first decade of early 21st century (2000-2012). My studies report that the glaciers in Himachal Pradesh lost mass more rapidly compared to other two regions in this period indicating the climate variability in the Karakoram–Himalaya. In addition, I also found the role of supraglacial debris and lakes that affect local changes on a glacier catchment scale and influences the glacier response to the climate change. In the second case study I will show the seasonal ice dynamics of Greenland’s ocean terminating glaciers. These glaciers significantly lose mass by discharging ice to oceans, which depends on ice flow, and contribute to global sea level. In this talk, I will show Greenland-wide changes in the ice flow of 221 glaciers on seasonal scales using Sentinel-1 space-borne radar mission. I will present how an advanced time-series analysis approach can reveal the general nature of these glaciers and related physical mechanisms that drive seasonal variations. This talk will also highlight my future science and measurement goals for glacier research in these regions and how a dedicated radar remote sensing lab, which, I wish to establish, can potentially resolve other dynamics processes (e.g. land subsidence in the coastal cities of India) apart from glacier changes.
