Intro to Glaciology

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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 .

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What Glaciers Are Telling Us About Earth's Changing Climate
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1 Overview 2 Mass Balance Equations
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