2014 IRIS/SSA Distinguished Lecturers

Dr. Meredith Nettles

Associate Professor of Earth and Environmental Sciences
Lamont-Doherty Earth Observatory,
Columbia University,
Palisades, New York

Glacial Earthquakes: Using Seismic and GPS Observations to Map Changes in Glaciers and Ice Sheets Worldwide

The great ice sheets of Greenland and Antarctica are losing mass, transferring more than 500 billion tons of water to the ocean each year. Most of this ice enters the ocean from large outlet glaciers: rivers of ice draining giant ice reservoirs. Understanding the behavior of the outlet glaciers is critical for accurate prediction of sea-level rise. The outlet glaciers are changing rapidly, with large variations in flow speed, thickness, and extent. In Greenland, many of the largest glaciers also produce seismic signals the size of those from magnitude 5 earthquakes, strong enough to be recorded around the globe.

The number of glacial earthquakes is increasing, with six times as many earthquakes occurring in recent years as in the early 1990s. I'll discuss the discovery of these peculiar earthquakes, and show how combining earthquake data with GPS measurements from glaciers allows us to learn how the glaciers and ice sheets may be affected by changing environmental conditions. Ice, the tides, earthquakes, and meltwater combine in a fascinating and complex system with real implications for our lives, whether on the coast or in the middle of the continent.

Date Venue
Apr 07, 2014 7:00 PM OMSI Science Pub, The Hollywood Theatre, Portland, Oregon
Sep 23, 2014 6:00 PM New Mexico Museum of Natural History and Science, Albuquerque, New Mexico
Nov 12, 2014 2:00 PM American Museum of Natural History, New York, New York

Dr. Jean-Paul Ampuero

Assistant Professor of Seismology
California Institute of Technology,
Pasadena, California

Earth's Cocktail Party: Deciphering the Physics of Earthquakes With Networks of Seismic Arrays

Date Venue
May 10, 2014 2:00 PM Fernbank Science Center, Atlanta, Georgia
Oct 14, 2014 2:30 PM Noel Wein Public Library, Fairbanks, Alaska
Jan 31, 2015 9:00 AM Rutgers, The State University of New Jersey, Rutgers, New Jersey