Seminar: Dr. Jonathan Martin – University of Florida

UNC-CH’s Department of Earth, Marine, and Environmental Sciences is proud to host a guest seminar by Dr. Jonathan Martin. This event is scheduled for Wednesday, October 27th, at 12:30 pm. This seminar is both in-person, in room G201 on the ground floor of Murray/Venable Hall on UNC campus in Chapel Hill NC and will be broadcasted live online via Zoom (Meeting ID: 994 3817 3742).

Presenter Affiliation: Professor, Department of Geological Sciences at the University of Florida

Title: High Latitude Hydrology: Water in a changing World

Abstract: Continued retreat of continental ice sheets from the Last Glacial Maximum (LGM) to today exposed ~15% of Earth’s previously glaciated land surface.  During that retreat and again now as current anthropogenic warming accelerates melting, glacial meltwater has delivered solutes, including nutrients, to the ocean and exchanged greenhouse gases with the atmosphere.  This meltwater is not the only source of solutes and gases, however; non-glacial streams draining the exposed deglaciated landscapes interact with the exposed, fine-grained, glacial sediment and generate solute and gas exports that are distinct from meltwater exports.  Differences in export fluxes depend on many factors including weathering reaction mechanisms, biogeochemical cycling, stream water concentrations, and discharge magnitudes.  In this talk, I will compare chemical compositions of streams draining multiple glacial and deglaciated watersheds in southwestern and southern Greenland to evaluate their relative solute exports and gas exchange and examine the landscape processes that affect export magnitudes.  The goals of this project are to understand causes of geochemical differences between watershed types to improve assessments of changes in ocean and atmospheric chemistry during past deglaciations and predictions of these changes associated with enhanced melting in a future warmer world.