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3. Glacier Mapping and Monitoring Using Multispectral Data

Author

Kääb, Andreas, Bolch, Tobias, Casey, Kimberly, Heid, Torborg, Kargel, Jeffrey S., Leonard, Gregory J., Paul, Frank, Raup, Bruce H., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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4. A world of changing glaciers: Summary and climatic context

Author

Kargel, Jeffrey S., Bush, Andrew B. G., Graham Cogley, J., Leonard, Gregory J., Raup, Bruce H., Smiraglia, Claudio, Pecci, Massimo, Ranzi, Roberto, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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5. New Zealand’s Glaciers

Author

Chinn, Trevor J., Kargel, Jeffrey S., Leonard, Gregory J., Haritashya, Umesh K., Pleasants, Mark, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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7. Introduction: Global Glacier Monitoring—a Long-Term Task Integrating in Situ Observations and Remote Sensing

Author

Zemp, Michael, Armstrong, Richard, Gärtner-Roer, Isabelle, Haeberli, Wilfried, Hoelzle, Martin, Kääb, Andreas, Kargel, Jeffrey S., Khalsa, Siri Jodha S., Leonard, Gregory J., Paul, Frank, Raup, Bruce H., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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8. Himalayan Glaciers (India, Bhutan, Nepal): Satellite Observations of Thinning and Retreat

Author

Racoviteanu, Adina E., Arnaud, Yves, Baghuna, I. M., Bajracharya, Samjwal R., Berthier, Etienne, Bhambri, Rakesh, Bolch, Tobias, Byrne, Martin, Chaujar, Ravinder K., Frauenfelder, Regula, Kääb, Andreas, Kamp, Ulrich, Kargel, Jeffrey S., Kulkarni, Anil V., Leonard, Gregory J., Mool, Pradeep K., Sossna, I., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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9. Glaciers and Perennial Snowfields of the U.S. Cordillera

Author

Fountain, Andrew G., Basagic, Hassan J., IV, Cannon, Charles, Devisser, Mark, Hoffman, Matthew J., Kargel, Jeffrey S., Leonard, Gregory J., Thorneykroft, Kristina, Wilson, Steve, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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10. Multispectral image analysis of glaciers and glacier lakes in the Chugach Mountains, Alaska

Author

Kargel, Jeffrey S., Beedle, Matthew J., Bush, Andrew B.G., Carreño, Francisco, Castellanos, Elena, Haritashya, Umesh K., Leonard, Gregory J., Lillo, Javier, Lopez, Ivan, Pleasants, Mark, Pollock, Edward, Wolfe, David F.G., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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15. The Chaotic Terrains of Mercury Reveal a History of Planetary Volatile Retention and Loss in the Innermost Solar System

Author

Rodriguez, J. Alexis P., primary, Leonard, Gregory J., additional, Kargel, Jeffrey S., additional, Domingue, Deborah, additional, Berman, Daniel C., additional, Banks, Maria, additional, Zarroca, Mario, additional, Linares, Rogelio, additional, Marchi, Simone, additional, Baker, Victor R., additional, Webster, Kevin D., additional, and Sykes, Mark, additional

Published
2020
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16. Geology and landscape evolution of the Hellas region of Mars

Author

Tanaka, Kenneth L and Leonard, Gregory J

Subjects
Lunar And Planetary Exploration
Abstract

Hellas basin on Mars has been the site of volcanism, tectonism, and modification by fluvial, mass-wasting, and eolian processes over its more than 4-b.y. existence. Our detailed geologic mapping and related studies have resulted in the following new interpretations. The asymmetric distribution of highland massifs and other structures that define the uplifted basin rim suggest a formation of the basin by the impact of a low-angle bolide having a trajectory heading S 60 deg E. During the Late Noachian, the basin was infilled, perhaps by lava flows, that were sufficiently thick (>1 km) to produce wrinkle ridges on the fill material and extensional faulting along the west rim of the basin. At about the same time, deposits buried northern Malea Planum, which are interpreted to be pyroclastic flows from Amphitrites and Peneus Paterae on the basis of their degraded morphology, topography, and the application of a previous model for pyroclastic volcanism on Mars. Peneus forms a distinctive caldera structure that indicates eruption of massive volumes of magma, whereas Amphitrites is a less distinct circular feature surrounded by a broad, low, dissected shield that suggests generally smaller volume eruptions. During the Early Hesperian, an approx. 1- to 2-km-thick sequence of primarily fined-grained, eolian material was deposited on the floor of Hellas basin. Subsequently, the deposit was deeply eroded, except where armored by crater ejecta, and it retreated as much as 200-300 km along its western margin, leaving behind pedestal craters and knobby outliers of the deposit. Local debris flows within the deposit attest to concentrations of groundwater, perhaps in part brought in by outflow floods along the east rim of the basin. These floods may have deposited approx. 100-200 m of sediment, subduing wrinkle ridges in the eastern part of the basin floor. During the Late Hesperian and Amazonian, eolian mantles were emplaced on the basin rim and floor and surrounding highlands. Their subsequent erosion resulted in pitted and etched plains and crater fill, irregular mesas, and pedestal craters. Local evidence occurs for the possible former presence of ground ice or ice sheets approx. 100 km across; however, we disagree with a hypothesis that suggests that the entire south rim and much of the floor of Hellas have been glaciated. Orientations of dune fields and yardangs in lower parts of Hellas basin follow directions of the strongest winds predicted by a recently published general circulation model (GCM). Transient frost and dust splotches in the region are, by contrast, related to the GCM prediction for the season in which the images they appear in were taken.

Published
1995

17. Hellas basin, Mars: Formation by oblique impact

Author

Leonard, Gregory J and Tanaka, Kenneth L

Subjects
Lunar And Planetary Exploration
Abstract

Hellas, a 2,000-km-diameter, roughly circular multiring impact basin in the southern highlands of Mars, has a pronounced southeastern lobe of rim material that extends for some 1,500 km. This lobe and a system of ridges concentric to the southern part of the basin (including part of the lobe) were interpreted to be formed by an oblique impact that was inclined in the direction of the lobe. Our preliminary geologic mapping of the Hellas region (lat -20 to -65 deg, long 250 to 320 deg) at 1:5,000,000 scale gives this hypothesis additional supporting evidence, including a symmetric distribution of basin ejecta and volcanic centers across the inferred trend of the impact. Furthermore, measurements of relief indicate that the downrange ejecta may be about twice as thick as they are elsewhere around the rim.

Published
1993

19. Erratum to “New insights into the Late Amazonian zonal shrinkage of the Martian south polar plateau” [Icarus 248 (2015) 407–411]

Author

Rodriguez, J. Alexis P., primary, Leonard, Gregory J., additional, Platz, Thomas, additional, Tanaka, Kenneth L., additional, Kargel, Jeffrey S., additional, Fairén, Alberto G., additional, Gulick, Virginia, additional, Baker, Victor R., additional, Glines, Natalie, additional, Miyamoto, Hideaki, additional, Jianguo, Yan, additional, and Oguma, Midori, additional

Published
2015
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21. Glacier mapping and monitoring based on spectral data

Author

Andreas Kääb, Bolch, Tobias, Casey, Kimberly A., Heid, Torborg, Kargel, Jeffrey S., Leonard, Gregory J., Paul, Frank, Raup, Bruce H., University of Zurich, Kargel, Jeffrey S, Leonard, Gregory J, Bishop, Michael P, Kääb, Andreas, and Raup, Bruce H

Subjects
10122 Institute of Geography, 910 Geography & travel

22. Evolution and Controls of Large Glacial Lakes in the Nepal Himalaya.

Author

Haritashya, Umesh K., Kargel, Jeffrey S., Shugar, Dan H., Leonard, Gregory J., Strattman, Katherine, Watson, C. Scott, Shean, David, Harrison, Stephan, Mandli, Kyle T., and Regmi, Dhananjay

Subjects
GLACIERS, LAKES, REMOTE sensing, EARTH sciences, BIOGEOCHEMICAL cycles, CLIMATOLOGY, CLIMATE change
Abstract

Glacier recession driven by climate change produces glacial lakes, some of which are hazardous. Our study assesses the evolution of three of the most hazardous moraine-dammed proglacial lakes in the Nepal Himalaya—Imja, Lower Barun, and Thulagi. Imja Lake (up to 150 m deep; 78.4 × 106 m3 volume; surveyed in October 2014) and Lower Barun Lake (205 m maximum observed depth; 112.3 × 106 m3 volume; surveyed in October 2015) are much deeper than previously measured, and their readily drainable volumes are slowly growing. Their surface areas have been increasing at an accelerating pace from a few small supraglacial lakes in the 1950s/1960s to 1.33 km2 and 1.79 km2 in 2017, respectively. In contrast, the surface area (0.89 km2) and volume of Thulagi lake (76 m maximum observed depth; 36.1 × 106 m3; surveyed in October 2017) has remained almost stable for about two decades. Analyses of changes in the moraine dams of the three lakes using digital elevation models (DEMs) quantifies the degradation of the dams due to the melting of their ice cores and hence their natural lowering rates as well as the potential for glacial lake outburst floods (GLOFs). We examined the likely future evolution of lake growth and hazard processes associated with lake instability, which suggests faster growth and increased hazard potential at Lower Barun lake. [ABSTRACT FROM AUTHOR]

Published
2018
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23. Remote sensing of recent glacier changes in the Canadian Arctic

Author

Sharp, Martin, Burgess, David O., Cawkwell, Fiona, Copland, Luke, Davis, James A., Dowdeswell, Evelyn K., Dowdeswell, Julian A., Gardner, Alex S., Mair, Douglas, Wang, Libo, Williamson, Scott N., Wolken, Gabriel J., Wyatt, Faye, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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24. Quality in the GLIMS Glacier Database

Author

Raup, Bruce H., Khalsa, Siri Jodha S., Armstrong, Richard L., Sneed, William A., Hamilton, Gordon S., Paul, Frank, Cawkwell, Fiona, Beedle, Matthew J., Menounos, Brian P., Wheate, Roger D., Rott, Helmut, Shiyin, Liu, Xin, Li, Donghui, Shangguan, Guodong, Cheng, Kargel, Jeffrey S., Larsen, Chris F., Molnia, Bruce F., Kincaid, Joni L., Klein, Andrew, Konovalov, Vladimir, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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25. Digital Terrain Modeling and Glacier Topographic Characterization

Author

Quincey, Duncan J., Bishop, Michael P., Kääb, Andreas, Berthier, Etienne, Flach, Boris, Bolch, Tobias, Buchroithner, Manfred, Kamp, Ulrich, Khalsa, Siri Jodha Singh, Toutin, Thierry, Haritashya, Umesh K., Racoviteanu, Adina, Shroder, John F., Raup, Bruce H., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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29. Radiative Transfer Modeling in the Cryosphere

Author

Furfaro, Roberto, Previti, Alberto, Picca, Paolo, Kargel, Jeffrey S., Bishop, Michael P., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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33. Monitoring Glacier Changes on the Antarctic Peninsula

Author

Arigony-Neto, Jorge, Skvarca, Pedro, Marinsek, Sebastián, Braun, Matthias, Humbert, Angelika, Júnior, Cláudio Wilson Mendes, Jaña, Ricardo, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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37. Glaciers in China and Their Variations

Author

Shiyin, Liu, Donghui, Shangguan, Junli, Xu, Xin, Wang, Xiaojun, Yao, Zongli, Jiang, Wanqin, Guo, Anxin, Lu, Shiqiang, Zhang, Baisheng, Ye, Zhen, Li, Junfeng, Wei, Lizong, Wu, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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38. Remote Sensing of Glaciers in Afghanistan and Pakistan

Author

Bishop, Michael P., Shroder, John F., Jr., Ali, Ghazanfar, Bush, Andrew B. G., Haritashya, Umesh K., Roohi, Rakhshan, Sarikaya, Mehmet Akif, Weihs, Brandon J., Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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39. European Alps

Author

Paul, Frank, Arnaud, Yves, Ranzi, Roberto, Rott, Helmut, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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42. Norway

Author

Andreassen, Liss M., Paul, Frank, Hausberg, Jon Endre, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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46. A digital glacier database for svalbard

Author

König, Max, Nuth, Christopher, Kohler, Jack, Moholdt, Geir, Pettersen, Rickard, Kargel, Jeffrey S., editor, Leonard, Gregory J., editor, Bishop, Michael P., editor, Kääb, Andreas, editor, and Raup, Bruce H., editor

Published
2014
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47. Quality in the GLIMS glacier database

Author

Shangguan Dong-hui, Bruce Raup, Matthew J. Beedle, Siri Jodha Singh Khalsa, Roger Wheate, Frank Paul, Bruce F. Molnia, Fiona Cawkwell, Joni L. Kincaid, Cheng Guodong, Gordon S. Hamilton, Jeffrey S. Kargel, Brian Menounos, Andrew Klein, Helmut Rott, Christopher F. Larsen, Xin Li, Richard L. Armstrong, Vladimir Konovalov, Liu Shiyin, William A. Sneed, University of Zurich, Kargel, Jeffrey S, Leonard, Gregory J, Bishop, Michael P, Kääb, Andreas, and Raup, Bruce H

Subjects
National Snow and Ice Data Center, geography, geography.geographical_feature_category, Database, Spatial database, Multispectral image, Glacier, Shuttle Radar Topography Mission, computer.software_genre, Consistency (database systems), 10122 Institute of Geography, Data quality, Environmental science, Satellite imagery, 910 Geography & travel, computer
Abstract

Global Land Ice Measurements from Space (GLIMS) is an international initiative to map the world’s glaciers and to build a geospatial database of glacier vector outlines that is usable via the World Wide Web. The GLIMS initiative includes glaciologists at 82 institutions, organized into 27 Regional Centers (RCs), who analyze satellite imagery to map glaciers in their regions of expertise. The results are collected at the U.S. National Snow and Ice Data Center (NSIDC) and ingested into the GLIMS Glacier Database. A concern for users of the database is data quality. The process of classifying multispectral satellite data to extract vector outlines of glaciers has been automated to some degree, but there remain stages requiring human interpretation. To quantify the repeatability and precision of data provided by different RCs, we designed a method of comparative image analysis whereby analysts at the RCs and NSIDC could derive glacier outlines from the same set of images, chosen to contain a variety of glacier types. We carried out four such experiments. The results were compiled, compared, and analyzed to quantify inter-RC analysis consistency. These comparisons have improved RC ability to produce consistent data, and in addition show that in the lower reaches of a glacier, precision of glacier outlines is typically 3 to 4 pixels. Variability in the accumulation area and over parts of the glacier that are debris covered tends to be higher. The ingest process includes quality control steps that must be passed before data are accepted into the database. These steps ensure that ingested data are well georeferenced and internally consistent. The GLACE experiments and ingest time quality control steps have led to improved quality and consistency of GLIMS data. This chapter presents the GLACE experiments and the quality control steps incorporated in the data ingest process. More recent similar studies are referenced.

Published
2014

48. Introduction: Global Glacier Monitoring—a Long-Term Task Integrating in Situ Observations and Remote Sensing

Author

Gregory J. Leonard, Siri Jodha Singh Khalsa, Richard L. Armstrong, Michael Zemp, Isabelle Gärtner-Roer, Frank Paul, Bruce Raup, Martin Hoelzle, Andreas Kääb, Jeffrey S. Kargel, Wilfried Haeberli, University of Zurich, Kargel, Jeffrey S, Leonard, Gregory J, Bishop, Michael P, Kääb, Andreas, and Raup, Bruce H

Subjects
Background information, geography, Glacier mass balance, 10122 Institute of Geography, geography.geographical_feature_category, Remote sensing (archaeology), Satellite remote sensing, Glacier, Ice caps, 910 Geography & travel, Remote sensing, Task (project management), Term (time)
Abstract

This book focuses on the complexities of glaciers as documented via satellite observations. The complexities drive much scientific interest in the subject. The essence—that the world’s glaciers and ice caps exhibit overwhelming retreat—is also developed by this book. In this introductory chapter, we aim at providing the reader with background information to better understand the integration of the glacier-mapping initiative known as Global Land Ice Measurements from Space (GLIMS, http://www.glims.org ) within the framework of internationally coordinated glacier-monitoring activities. The chapter begins with general definitions of perennial ice on land and its global coverage, followed by a section on the relation between glaciers and climate. Brief overviews on the specific history of internationally coordinated glacier monitoring and the global monitoring strategy for glaciers and ice caps are followed by a summary of available data. We introduce the potential and challenges of satellite remote sensing for glacier monitoring in the 21st century and emphasize the importance of integrative change assessments. Lastly, we provide a synopsis of the book structure as well as some concluding remarks on worldwide glacier monitoring.

Published
2014

49. Remote Sensing of Glaciers in the Canadian Cordillera, Western Canada

Author

Roger Wheate, Etienne Berthier, John J. Clague, Erik Schiefer, Joseph M. Shea, Brian Menounos, Tobias Bolch, University of Zurich, Kargel, Jeffrey S, Leonard, Gregory J, Bishop, Michael P, Kääb, Andreas, and Raup, Bruce H

Subjects
geography, geography.geographical_feature_category, Thinning, Elevation, Glacier, Shuttle Radar Topography Mission, 10122 Institute of Geography, Remote sensing (archaeology), Period (geology), Physical geography, 910 Geography & travel, Digital elevation model, Volume loss, Geology
Abstract

We review the use of spaceborne imagery and digital elevation models (DEMs) to evaluate glacier thinning and retreat in the Canadian Cordillera, an area that includes the provinces of British Columbia (BC), Alberta, and Yukon Territory. Glaciers in Alberta and British Columbia lost 11.1 ± 3.8 % of their area over the period 1985–2005, which represents an approximate annual shrinkage rate of 0.55 %. For the period 1985–1999 the average thinning rate of sampled glaciers was 0.78 ± 0.19 m/year water equivalent (w.e.), which equates to an annual volume loss of 22.48 ± 5.53 km3. Mean annual ice loss in the Yukon between 1977 and 2007 was 5.5 ± 1.7 km3/year, while the average mass balance for Yukon glaciers over this period was −0.45 ± 0.09 m/year. We also summarize changes in glacier extents and surface elevation from 1965 to 2005, and include examples of surging glaciers in the Yukon and glacier hazards in British Columbia.

Published
2014

50. Remote sensing of rapidly diminishing tropical glaciers in the northern Andes

Author

Jorge Luis Ceballos, Andrew Klein, Christian Huggel, Adina Racoviteanu, Yves Arnaud, Joni L. Kincaid, Walter Silverio, Todd Albert, University of Zurich, Kargel, Jeffrey S, Leonard, Gregory J, Bishop, Michael P, Kääb, Andreas, and Raup, Bruce H

Subjects
Glacier mass balance, geography, 10122 Institute of Geography, geography.geographical_feature_category, Remote sensing (archaeology), Range (biology), Tropical climate, Deglaciation, Period (geology), Tropics, Glacier, 910 Geography & travel, Remote sensing
Abstract

This chapter presents an overview of some of the changes recently observed on glaciated areas in the tropical Andes of South America. Tropical glaciers are exceptional indicators of shifts in tropical climate, and the Andes are home to almost 99 % of the world’s tropical ice cover (Kaser et al. 1996). Many of the glaciated cordilleras in the northern Andes are mere remnants of what existed 50 years ago. Here we present a history of deglaciation of the Quelccaya Ice Cap in Peru, the largest body of ice in the tropics, which has lost approximately 30 % of its total area in the last 35 years; the Cordillera Blanca, a glaciated range in Peru, which has lost over 20 % of its area in the same period; glaciers in Colombia that have lost between 20–50 % or more of their area in the last few decades; Tres Cruces, a glaciated area in Bolivia, which has lost over half of its area; and one glacier in Venezuela that has lost over 90 % of its area. These changes are quite representative of overall glacier retreat throughout the tropical Andes.

Published
2014

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