Intro to Glaciology

Drs. Dan McGrath and Doug MacAyeal CSU/USGS Glacial Seismology School June 12, 2017 Outline • Brief history • The who, what, and where • Glacier mass balance • Glacier flow • Glacier hydrology • Glacial geology • Glacier and ice sheet mass balance; contribution to SLR A long history…. Ice and Glaciers Glaciers and Ice Sheets

NASA Earth Observatory Classifying glaciers

Thermal Landscape/Size

Tidewater glacier

Anderson and Anderson, 2010 Cirque Glaciers Valley Glaciers Ice Sheets Ice Caps Ice Shelves Sea Ice

Sea ice covers most Sea ice fringes the entire of the Arctic Ocean. continent of Antarctica. Glacier Mass Balance

Anderson and Anderson, 2010 Antarcticglaciers.org

Glacier mass balance Balance Profiles

Local Change in Ice mass thickness discharge with time balance Glacier mass balance

Cogley et al., 2011 How do we measure mass balance?

W. Colgan The Movement of Glacial Ice The Movement of Glacial Ice

Valley Glacier H = 130 m, θ = 5°

Ice sheet H =1300 m, θ = 0.5°

Ice rheology and Glen’s Flow Law

Velocity

Discharge Velocity Observations AIS Ice Velocity Ice Streams

Winberry et al., 2009 Glacier Hydrology

Vena Chu

Supraglacial Englacial Basal Hydrology and Ice velocity

Bartholomaus et al,. 2015 Bartholomaus et al., 2008 Crevasses

Colgan et al., 2016 Tidewater Glaciers Iceberg Calving

Benn et al., 2007 Anderson and Anderson, 2010 Luckman et al., 2016 Columbia Glacier, Alaska

http://earthobservatory.nasa.gov/Features/WorldOfChange/columbia_glacier.php Tidewater glacier cycle Marine Ice Sheet Instability

Cryoseismology

Podolskiy and Walter, 2016 Glacial Erosion Glacial Erosional Landscapes Glacial Erosional Landscapes Glacial Erosional Landscapes Depositional Landforms Drumlins Kettle Lakes

Ice sheet mass balance from 1992-2011. Shepherd et al., 2013.

Regional glacier mass balance from 2003- 2009. Gardner et al., 2013

Pritchard et al., 2009; Nature