Remote weather stations, like this one at Wolverine Glacier, collect data near each glacier so scientists can understand regional climate influence on the glaciers.
Louis Sass, III
Glacier mass balance; physical processes of glacier mass balance; feedback mechanisms on glacier mass balance; glacier influences on streamflow
I came to Alaska in 1999 to climb in the Alaska Range, and returned to work as an outdoor educator and mountain guide. At the time that was not part of a grand plan to intimately familiarize myself with glacier behavior, but I found myself increasingly interested in the physical processes of glacier change. Now I am the project lead for the Alaska portion of the Benchmark Glacier Project, a long-term project that quantifies seasonal mass changes on five glaciers in the US, three of which are in Alaska. My research focuses on accurately quantifying glacier change, understanding the physical processes that contribute to that change, and identifying feedback mechanisms that influence future changes. I work to understand how glaciers (and glacier change) influence surrounding ecosystems, both directly in terms of downstream runoff to rivers and oceans, and indirectly in terms of the overall ecosystem and landscape evolution. I am also interested in trying to make glacier science and glacier data more digestible and more approachable for land managers, decision makers, and the public.
Science and Products
Glaciers and Climate Project
Mountain glaciers are dynamic reservoirs of frozen water closely coupled to ecosystems and climate. Glacier change in North America has major socioeconomic impacts, including global sea level change, tourism disruption, natural hazard risk, fishery effects, and water resource alteration. Understanding and quantifying precise connections between glaciers and climate is critical to decision makers...
Gulkana Glacier
Gulkana Glacier is located in the high-latitude continental climate regime of Alaska’s Delta Mountains. Glacier observations began at this site in 1966.
Lemon Creek Glacier
Lemon Creek Glacier is located in the high-latitude maritime region of Alaska, at the southernmost tip of the Juneau Icefield. Glacier observations began at this site in 1953.
Wolverine Glacier
Wolverine Glacier is located in the high-latitude maritime climate regime of Alaska’s Kenai Mountains. Glacier observations began at this site in 1966.
Assessing the Vulnerability of Alaska’s Glaciers in a Changing Climate
Retreating glaciers are an iconic image of climate change;yet not all glaciers in Alaska are actively retreating, and a few glaciers are even advancing. While this contrasting behavior can be misleading for the casual observer, variable responses between glaciers in a changing climate are expected. Glaciers act as conveyor belts that transport snow and ice from high elevations, where it does not m
USGS Benchmark Glacier Project
Scientists with the USGS Benchmark Glacier Project study the process and impacts of glacier change, including sea-level rise, water resources, environmental hazards and ecosystem links. At the core of this research are mass balance measurements at five glaciers in the United States. Since the 1960s, these glaciers have been studied using direct observations of glaciers and meteorology. The project...
Wolverine Glacier Ecosystem Studies
This project is an extension of the long-term Wolverine Glacier Benchmark Glacier project and is improving our understanding of solutes and nutrients in glacier basins, and how they fuel downstream ecosystems.
Filter Total Items: 29
Sun setting on weather station at Wolverine Glacier
Remote weather stations, like this one at Wolverine Glacier, collect data near each glacier so scientists can understand regional climate influence on the glaciers.
Scientist with data notebook
Scientist uses radio-echo-sounding to study firn compaction on Wolverine Glacier, Alaska. Radio-echo sounding (RES) is a technique used by glaciologists to measure the internal structure, ice thickness and sub-ice morphology of glaciers. This tool is equivalent to X-rays for the medical profession and the physicists.
Scientist uses radio-echo-sounding to study firn compaction on Wolverine Glacier, Alaska. Radio-echo sounding (RES) is a technique used by glaciologists to measure the internal structure, ice thickness and sub-ice morphology of glaciers. This tool is equivalent to X-rays for the medical profession and the physicists.
Weighing type precipitation gage and new radar-based sensor
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. On October 19, 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage.
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. On October 19, 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage.
Upgraded Wolverine Glacier weather station, Alaska
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. In Ocotober 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage. The
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. In Ocotober 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage. The
Close up of the new radar precipitation sensor on the top of the pole
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. Close up of the new radar precipitation sensor on the top of the pole. The crazy looking thing in the middle of the picture is an aspirated temperature sensor.
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. Close up of the new radar precipitation sensor on the top of the pole. The crazy looking thing in the middle of the picture is an aspirated temperature sensor.
Wolverine Glacier weather station on the Kenai Peninsula, Alaska
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula.
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula.
Ablation stakes on Gulkana Glacier
Ablation stakes on Gulkana Glacier, Alaska. Late summer fieldwork on Gulkana Glacier reveals ablation stakes emerging from the ice. Measurements of the change in the height of the snow and ice at these stakes is one aspect of determining glacier mass balance.
Ablation stakes on Gulkana Glacier, Alaska. Late summer fieldwork on Gulkana Glacier reveals ablation stakes emerging from the ice. Measurements of the change in the height of the snow and ice at these stakes is one aspect of determining glacier mass balance.
Gulkana Glacier weather station
A scientist checks data collection on multiple sensors at the Gulkana Glacier weather station where snow blankets the glacier surface.
A scientist checks data collection on multiple sensors at the Gulkana Glacier weather station where snow blankets the glacier surface.
Ice core extracted from Wolverine Glacier, Alaska
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
Coring snow
A scientist prepares to extract a snow core from one of the Benchmark Glaciers. Cores are used to determine the density of the snow and ice on the surface of the glacier in order to determine the mass balance.
A scientist prepares to extract a snow core from one of the Benchmark Glaciers. Cores are used to determine the density of the snow and ice on the surface of the glacier in order to determine the mass balance.
Scientists use ground penetrating radar on Wolverine Glacier, AK
Researchers use ground penetrating radar to determine the depth of the snow on Wolverine Glacier. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, one of the "benchmark glaciers" in Alaska.
Researchers use ground penetrating radar to determine the depth of the snow on Wolverine Glacier. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, one of the "benchmark glaciers" in Alaska.
Wolverine Glacier
A researcher locates an ablation stake near a crevasse on Wolverine Glacier. These collapsible poles are used to measure snow and ice melt on the glacier surface.
A researcher locates an ablation stake near a crevasse on Wolverine Glacier. These collapsible poles are used to measure snow and ice melt on the glacier surface.
Scientist examines firn core
USGS scientist Louis Sass examines a full firn core taken on Wolverine Glacier, making observations of any notable dust or dirt layers in the snow and firn stratigraphy.
USGS scientist Louis Sass examines a full firn core taken on Wolverine Glacier, making observations of any notable dust or dirt layers in the snow and firn stratigraphy.
Collecting data at an ablation stake on Wolverine Glacier
USGS scientist, Chris McNeil, collects data at an ablation stake on Wolverine Glacier near the end of the glacial melt season.
USGS scientist, Chris McNeil, collects data at an ablation stake on Wolverine Glacier near the end of the glacial melt season.
Gulkana Glacier
Heavily crevassed glacial ice flows across scoured rock in late summer at Gulkana Glacier, AK.
Heavily crevassed glacial ice flows across scoured rock in late summer at Gulkana Glacier, AK.
Gulkana Glacier
Gulkana Glacier is located along the south flank of the eastern Alaska Range.
Gulkana Glacier is located along the south flank of the eastern Alaska Range.
Crevassed terminus of Gulkana Glacier
Heavily crevassed terminus of Gulkana Glacier, AK, near the end of the 2016 ablation (melt) season.
Heavily crevassed terminus of Gulkana Glacier, AK, near the end of the 2016 ablation (melt) season.
A scientist dumps DNA tracer into a moulin on Wolverine Glacier
A scientist dumps DNA tracer into a moulin on Wolverine Glacier to assess water flow through the glacier as part of research aimed at understanding glacier processes.
A scientist dumps DNA tracer into a moulin on Wolverine Glacier to assess water flow through the glacier as part of research aimed at understanding glacier processes.
Scientist with ablation stake
Scientist with ablation stake on Wolverine Glacier in Alaska. Scientist probes to determine snow depth near another ablation stake.
Scientist with ablation stake on Wolverine Glacier in Alaska. Scientist probes to determine snow depth near another ablation stake.
Measuring a snow core
Measuring a snow core. The layers that make up snow cores are measured to determine the density of the snow and ice.
Measuring a snow core. The layers that make up snow cores are measured to determine the density of the snow and ice.
South Cascade Glacier, northwestern Washington State
South Cascade Glacier, northwestern Washington State. South Cascade Glacier located in a north-northwest facing valley near the crest of the Cascade Range in northwest Washington state. In 1959 scientists with the USGS began collecting mass balance data on South Cascade Glacier, now one of five "benchmark glaciers" in the US.
South Cascade Glacier, northwestern Washington State. South Cascade Glacier located in a north-northwest facing valley near the crest of the Cascade Range in northwest Washington state. In 1959 scientists with the USGS began collecting mass balance data on South Cascade Glacier, now one of five "benchmark glaciers" in the US.
Science and Products
Glaciers and Climate Project
Mountain glaciers are dynamic reservoirs of frozen water closely coupled to ecosystems and climate. Glacier change in North America has major socioeconomic impacts, including global sea level change, tourism disruption, natural hazard risk, fishery effects, and water resource alteration. Understanding and quantifying precise connections between glaciers and climate is critical to decision makers...
Gulkana Glacier
Gulkana Glacier is located in the high-latitude continental climate regime of Alaska’s Delta Mountains. Glacier observations began at this site in 1966.
Lemon Creek Glacier
Lemon Creek Glacier is located in the high-latitude maritime region of Alaska, at the southernmost tip of the Juneau Icefield. Glacier observations began at this site in 1953.
Wolverine Glacier
Wolverine Glacier is located in the high-latitude maritime climate regime of Alaska’s Kenai Mountains. Glacier observations began at this site in 1966.
Assessing the Vulnerability of Alaska’s Glaciers in a Changing Climate
Retreating glaciers are an iconic image of climate change;yet not all glaciers in Alaska are actively retreating, and a few glaciers are even advancing. While this contrasting behavior can be misleading for the casual observer, variable responses between glaciers in a changing climate are expected. Glaciers act as conveyor belts that transport snow and ice from high elevations, where it does not m
USGS Benchmark Glacier Project
Scientists with the USGS Benchmark Glacier Project study the process and impacts of glacier change, including sea-level rise, water resources, environmental hazards and ecosystem links. At the core of this research are mass balance measurements at five glaciers in the United States. Since the 1960s, these glaciers have been studied using direct observations of glaciers and meteorology. The project...
Wolverine Glacier Ecosystem Studies
This project is an extension of the long-term Wolverine Glacier Benchmark Glacier project and is improving our understanding of solutes and nutrients in glacier basins, and how they fuel downstream ecosystems.
Filter Total Items: 29
Sun setting on weather station at Wolverine Glacier
Remote weather stations, like this one at Wolverine Glacier, collect data near each glacier so scientists can understand regional climate influence on the glaciers.
Remote weather stations, like this one at Wolverine Glacier, collect data near each glacier so scientists can understand regional climate influence on the glaciers.
Scientist with data notebook
Scientist uses radio-echo-sounding to study firn compaction on Wolverine Glacier, Alaska. Radio-echo sounding (RES) is a technique used by glaciologists to measure the internal structure, ice thickness and sub-ice morphology of glaciers. This tool is equivalent to X-rays for the medical profession and the physicists.
Scientist uses radio-echo-sounding to study firn compaction on Wolverine Glacier, Alaska. Radio-echo sounding (RES) is a technique used by glaciologists to measure the internal structure, ice thickness and sub-ice morphology of glaciers. This tool is equivalent to X-rays for the medical profession and the physicists.
Weighing type precipitation gage and new radar-based sensor
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. On October 19, 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage.
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. On October 19, 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage.
Upgraded Wolverine Glacier weather station, Alaska
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. In Ocotober 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage. The
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. In Ocotober 2020, USGS scientists upgraded the power system to a Lithium battery bank and installed a radar-based precipitation sensor (Lufft WS-100) to compare with the weighing based precipitation gage. The
Close up of the new radar precipitation sensor on the top of the pole
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. Close up of the new radar precipitation sensor on the top of the pole. The crazy looking thing in the middle of the picture is an aspirated temperature sensor.
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula. Close up of the new radar precipitation sensor on the top of the pole. The crazy looking thing in the middle of the picture is an aspirated temperature sensor.
Wolverine Glacier weather station on the Kenai Peninsula, Alaska
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula.
The Wolverine Glacier weather station was installed in 1968, and at 3250 ft is the highest elevation long-term weather record on the Kenai Peninsula.
Ablation stakes on Gulkana Glacier
Ablation stakes on Gulkana Glacier, Alaska. Late summer fieldwork on Gulkana Glacier reveals ablation stakes emerging from the ice. Measurements of the change in the height of the snow and ice at these stakes is one aspect of determining glacier mass balance.
Ablation stakes on Gulkana Glacier, Alaska. Late summer fieldwork on Gulkana Glacier reveals ablation stakes emerging from the ice. Measurements of the change in the height of the snow and ice at these stakes is one aspect of determining glacier mass balance.
Gulkana Glacier weather station
A scientist checks data collection on multiple sensors at the Gulkana Glacier weather station where snow blankets the glacier surface.
A scientist checks data collection on multiple sensors at the Gulkana Glacier weather station where snow blankets the glacier surface.
Ice core extracted from Wolverine Glacier, Alaska
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
Coring snow
A scientist prepares to extract a snow core from one of the Benchmark Glaciers. Cores are used to determine the density of the snow and ice on the surface of the glacier in order to determine the mass balance.
A scientist prepares to extract a snow core from one of the Benchmark Glaciers. Cores are used to determine the density of the snow and ice on the surface of the glacier in order to determine the mass balance.
Scientists use ground penetrating radar on Wolverine Glacier, AK
Researchers use ground penetrating radar to determine the depth of the snow on Wolverine Glacier. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, one of the "benchmark glaciers" in Alaska.
Researchers use ground penetrating radar to determine the depth of the snow on Wolverine Glacier. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, one of the "benchmark glaciers" in Alaska.
Wolverine Glacier
A researcher locates an ablation stake near a crevasse on Wolverine Glacier. These collapsible poles are used to measure snow and ice melt on the glacier surface.
A researcher locates an ablation stake near a crevasse on Wolverine Glacier. These collapsible poles are used to measure snow and ice melt on the glacier surface.
Scientist examines firn core
USGS scientist Louis Sass examines a full firn core taken on Wolverine Glacier, making observations of any notable dust or dirt layers in the snow and firn stratigraphy.
USGS scientist Louis Sass examines a full firn core taken on Wolverine Glacier, making observations of any notable dust or dirt layers in the snow and firn stratigraphy.
Collecting data at an ablation stake on Wolverine Glacier
USGS scientist, Chris McNeil, collects data at an ablation stake on Wolverine Glacier near the end of the glacial melt season.
USGS scientist, Chris McNeil, collects data at an ablation stake on Wolverine Glacier near the end of the glacial melt season.
Gulkana Glacier
Heavily crevassed glacial ice flows across scoured rock in late summer at Gulkana Glacier, AK.
Heavily crevassed glacial ice flows across scoured rock in late summer at Gulkana Glacier, AK.
Gulkana Glacier
Gulkana Glacier is located along the south flank of the eastern Alaska Range.
Gulkana Glacier is located along the south flank of the eastern Alaska Range.
Crevassed terminus of Gulkana Glacier
Heavily crevassed terminus of Gulkana Glacier, AK, near the end of the 2016 ablation (melt) season.
Heavily crevassed terminus of Gulkana Glacier, AK, near the end of the 2016 ablation (melt) season.
A scientist dumps DNA tracer into a moulin on Wolverine Glacier
A scientist dumps DNA tracer into a moulin on Wolverine Glacier to assess water flow through the glacier as part of research aimed at understanding glacier processes.
A scientist dumps DNA tracer into a moulin on Wolverine Glacier to assess water flow through the glacier as part of research aimed at understanding glacier processes.
Scientist with ablation stake
Scientist with ablation stake on Wolverine Glacier in Alaska. Scientist probes to determine snow depth near another ablation stake.
Scientist with ablation stake on Wolverine Glacier in Alaska. Scientist probes to determine snow depth near another ablation stake.
Measuring a snow core
Measuring a snow core. The layers that make up snow cores are measured to determine the density of the snow and ice.
Measuring a snow core. The layers that make up snow cores are measured to determine the density of the snow and ice.
South Cascade Glacier, northwestern Washington State
South Cascade Glacier, northwestern Washington State. South Cascade Glacier located in a north-northwest facing valley near the crest of the Cascade Range in northwest Washington state. In 1959 scientists with the USGS began collecting mass balance data on South Cascade Glacier, now one of five "benchmark glaciers" in the US.
South Cascade Glacier, northwestern Washington State. South Cascade Glacier located in a north-northwest facing valley near the crest of the Cascade Range in northwest Washington state. In 1959 scientists with the USGS began collecting mass balance data on South Cascade Glacier, now one of five "benchmark glaciers" in the US.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government