Savor the Cryosphere Patrick A
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Nova Southeastern University NSUWorks Marine & Environmental Sciences Faculty Department of Marine and Environmental Sciences Proceedings, Presentations, Speeches, Lectures 8-2017 Savor the Cryosphere Patrick A. Burkhart Slippery Rock University of Pennsylvania Richard B. Alley Pennsylvania State University Lonnie G. Thompson Ohio State University James D. Balog Earth Vision Institute/Extreme Ice Survey Paul Baldauf Nova Southeastern University, [email protected] See next page for additional authors Follow this and additional works at: https://nsuworks.nova.edu/occ_facpresentations Part of the Earth Sciences Commons NSUWorks Citation Burkhart, Patrick A.; Alley, Richard B.; Thompson, Lonnie G.; Balog, James D.; Baldauf, Paul; and Baker, Gregory S., "Savor the Cryosphere" (2017). Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures. 476. https://nsuworks.nova.edu/occ_facpresentations/476 This Article is brought to you for free and open access by the Department of Marine and Environmental Sciences at NSUWorks. It has been accepted for inclusion in Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures by an authorized administrator of NSUWorks. For more information, please contact [email protected]. Authors Patrick A. Burkhart, Richard B. Alley, Lonnie G. Thompson, James D. Balog, Paul Baldauf, and Gregory S. Baker This article is available at NSUWorks: https://nsuworks.nova.edu/occ_facpresentations/476 Savor the Cryosphere Patrick A. Burkhart, Dept. of Geography, Geology, and the Environment, Slippery Rock University, Slippery Rock, Pennsylvania 16057, USA; Richard B. Alley, Dept. of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA; Lonnie G. Thompson, School of Earth Sciences, Byrd Polar and Climate Research Center, Ohio State University, Columbus, Ohio 43210, USA; James D. Balog, Earth Vision Institute/Extreme Ice Survey, 2334 Broadway Street, Suite D, Boulder, Colorado 80304, USA; Paul E. Baldauf, Dept. of Marine and Environmental Sciences, Nova Southeastern University, 3301 College Ave., Fort Lauderdale, Florida 33314, USA; and Gregory S. Baker, Dept. of Geology, University of Kansas, 1475 Jayhawk Blvd., Lawrence, Kansas 66045, USA ABSTRACT Cryosphere,” a Pardee Keynote Symposium loss of ice will pass to the future. The This article provides concise documen- at the 2015 Annual Meeting in Baltimore, extent of ice can be measured by satellites tation of the ongoing retreat of glaciers, Maryland, USA, for which the GSA or by ground-based glaciology. While we along with the implications that the ice loss recorded supporting interviews and a provide a brief assessment of the first presents, as well as suggestions for geosci- webinar. method, our focus on the latter is key to ence educators to better convey this story informing broad audiences of non-special- INTRODUCTION to both students and citizens. We present ists. The cornerstone of our approach is the the retreat of glaciers—the loss of ice—as The cryosphere is the portion of Earth use of repeat photography so that the scale emblematic of the recent, rapid contraction that is frozen, which includes glacial and and rate of retreat are vividly depicted. of the cryosphere. Satellites are useful for periglacial environs on land, where ice, Science is grounded in observation, so sci- assessing the loss of ice across regions permafrost, or snow cover dominate, as ence education will benefit from display- with the passage of time. Ground-based well as ice-covered sea. Geographically, ing the recently exposed landscapes. We glaciology, particularly through the study arctic regions and the higher elevation por- close by prompting people to value the of ice cores, can record the history of envi- tions of alpine regions at lower latitudes cryosphere and to recognize the conse- ronmental conditions present during the are included. We assert that the retreat of quences of fossil fuel consumption. existence of a glacier. Repeat photography glaciers—the loss of ice—is emblematic of RETREAT OF GLACIERS vividly displays the rapid retreat of glaciers the recent, rapid contraction of the cryo- that is characteristic across the planet. This sphere. Because relatively few people visit Earth is losing ice. The instances of gla- loss of ice has implications to rising sea such places due to their remoteness, we cial retreat far exceed those of advance. level, greater susceptibility to dryness in note the difficulty that many non-special- Zemp et al. (2015) reported glaciological places where people rely upon rivers deliv- ists have in recognizing the scope of this and geodetic observations of over 5,200 ering melt water resources, and to the issue. Our response is to explain ice loss in glaciers from nineteen regions around the destruction of natural environmental tangible terms that feature multimedia, as world, showing that the rates of early archives that were held within the ice. well as to provide geoscience educators twenty-first–century ice mass loss are with- Warming of the atmosphere due to rising with information for doing so themselves. out precedent, at least for the few-century concentrations of greenhouse gases We presented this topic as “Savor the observational period. The compilation released by the combustion of fossil fuels Cryosphere,” a Pardee Keynote of Zemp et al. (2008) shows that, since is causing this retreat. We highlight multi- Symposium at the 2015 Annual Meeting of 1900, retreating glaciers have been more media productions that are useful for the GSA in Baltimore, Maryland, USA. common than advancing ones (see http:// teaching this story effectively. As geosci- Archival interviews are available at https:// www.grid.unep.ch/glaciers/img/5-1.jpg). ence educators, we attempt to present the www.youtube.com/watch?v=d1-jzYuea9E, These inventories are based upon a variety best scholarship as accurately and elo- and a webinar is available at https:// of different approaches to measurement; quently as we can, to address the core chal- attendee.gotowebinar.com/recording/ hence, we present both remote and close lenge of conveying the magnitude of 5467381313092358658 (no charge to observation. anthropogenic impacts, while also encour- register to see the information). Our aging optimistic determination on the part approach here is to document glacial Space-Based Observation of students, coupled to an increasingly retreat, noting that rising air temperature is Satellites are useful for studying glaciers informed citizenry. We assert that under- the principal cause of it (coupled with for many reasons. Ice loss can be assessed standing human perturbation of nature, warming sea water and changes in ocean by repeat gravimetry, which quantifies then choosing to engage in thoughtful sci- currents in areas with tidewater glaciers), changes in ice mass, or by altimetry, which ence-based decision-making, is a wise then to review the implications of ice loss, contributes to measuring changing surface choice. This topic comprised “Savor the and finally to present the legacy that the elevation, coupled together with repeat GSA Today, v. 27, doi: 10.1130/GSATG293A.1. © The Geological Society of America, 2017. 160°W 120°W 60°W 20°W 20°E 60°E 100°E 140°E 180° 80°N 80°N 60°N 60°N 40°N 40°N 20°N 20°N 0° 0° 20°S 20°S 40°S 40°S 60°S 60°S 80°S 80°S Extreme Ice Survey 160°W 120°W 60°W 20°W 20°E 60°E 100°E 140°E 180° Penn State Ice and Climate Research Center Byrd Polar Research Center Coordinate System: World Flat Polar Quartic Central Meridian: 0°0'0" Figure 1. Global distribution of glaciers studied by the co-authors. imagery that displays changes in coverage Kääb et al. (2012) used satellite laser altim- authors assess findings from six conti- area (Gardner et al., 2013). As we shall see, etry and a global elevation model to report nents, where inquiry spans the study of ice comparison between results determined by widespread loss of ice in the Himalayas. sheets, ice caps, and mountain glaciers. various tools lends confidence to the find- While one recent study suggested slight The researchers at the Byrd Polar and ings. Remote sensing is advantageous growth of the Antarctic ice sheet as an Climate Research Center (BPCRC) and because glaciated terrain is remote and ongoing response to the increase in snow- Penn State Ice and Climate Exploration difficult to access (Luthcke et al., 2008). fall at the end of the last ice age (Zwally et have extracted, or helped to extract, ice Kääb (2008) also notes that spaceborne al., 2015), a study using a wider range of cores at the sites indicated. The ice cores techniques are sustainable for global-scale analytical techniques (Shepherd et al., provide histories of annual net balance and monitoring of glaciers because satellites 2012) indicates shrinkage at both poles. of precipitation chemistry. The Extreme can remain operational for decades. Several additional studies as summarized Ice Survey provides extensive archives of These observations provide robust docu- by Scambos and Shuman (2016) support time-lapse photography for a multitude of mentation of ice loss. Arendt et al. (2013) and extend the record of Antarctic mass glaciers, which reveal changes in the lat- reported a mass-balance for glaciers in the loss. Jacob et al. (2012) used GRACE eral extent and thickness of ice. Gulf of Alaska of -65 ± 11 Gt/a from 2003 results to calculate global ice change of Examples of ice loss are abundant and to 2010 from the Gravity Recovery and -536 ± 93 Gt/a between 2003 and 2010 by well documented. Since 1974, investigators Climate Experiment (GRACE), which summing the mass balance of twenty gla- at the BPCRC have monitored glaciers in compared well with their determination of ciated regions around the planet. Thus, South America, Africa, and Asia. In -65 ± 12 Gt/a from the Ice, Cloud, and satellites are very useful for assessing Tanzania, the total surface area of the ice land Elevation Satellite (ICESat) based changes in glaciers, both regionally and fields on top of Mount Kilimanjaro upon glacier elevation changes.