Operation IceBridge

Operation IceBridge was a NASA field campaign that was the largest airborne survey of Earth's polar ice ever flown. Spanning 11 years, IceBridge produced an unprecedented three-dimensional view of Arctic and Antarctic ice sheets, glaciers and sea ice. Dozens of flights every year provided regular, multi-instrument insights into the behavior of Earth’s rapidly changing cryosphere.

Data collected by IceBridge helped scientists bridge the gap in polar observations of ice height between NASA's Ice, Cloud and Land Elevation Satellite (ICESat), which launched in 2003, and ICESat-2, which launched on September 15, 2018. ICESat stopped collecting science data in 2009, making IceBridge critical for ensuring a continuous series of observations. IceBridge surveyed the Arctic and Antarctic areas once a year, typically in the springtime before summer melting began. The first Operation IceBridge flights were conducted in March/May 2009 over Greenland and in October/November 2009 over Antarctica. Other smaller airborne surveys around the world, in particular Alaska, were also part of the IceBridge mission.

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Arctic

The extensive data IceBridge has gathered over the Greenland ice sheet during its operations have provided an improved picture of the surface, the bed and the internal structures of Greenland’s ice sheet and allowed scientists to create more accurate models of glacier contribution to sea level rise. As for sea ice, IceBridge’s measurements of the thickness of sea ice and its snow cover have assisted in improving forecasts for summertime melt, enhanced the understanding of variations in ice thickness distribution from year to year, and updated the climatology of the snow depth over sea ice.
  • Operation IceBridge - Greenland Glaciers
    2019.12.09
    Greenland’s more than 200 major outlet glaciers are constantly on the move, most of them draining ice from the central ice sheet. Jakobshavn is Greenland’s fastest-moving glacier, and the flow rate is variable with spurts of speed in the summer and additional variation from year to year. When an ice tongue such as the Jakobshavn calves, the glacier feeding that ice tongue typically accelerates. Reduced friction between the intact glacier and the bedrock, and reduced buoyancy from the seawater (which partially offsets the glacier’s downhill flow) mean less resistance to glacier movement. Warming conditions in the Arctic contribute to glacier acceleration in multiple ways. Warmer conditions can send meltwater to the glacier’s base, increasing lubrication and consequently glacier speed. During the winter, the rate of iceberg calving usually slows significantly; the glacier tongue advances, and its flow speed drops. Warm winters, however, may allow iceberg calving and high flow rates to continue. Since 2000, Greenland has lost some 739 gigatons of ice, and approximately 30 percent of that loss came from Jakobshavn and four other glaciers
  • Operation IceBridge - Icebergs
    2019.12.09
    Icebergs start as land ice—snow that has accumulated on land and, over the course of many years, has been compacted into ice. When this glacial ice flows downstream and reaches the sea, cracks in the ice are widened as warm water and air melt the ice from below and above, respectively. When these cracks become large enough, pieces break off like fingernail clippings and drift into the water as icebergs.
  • Operation IceBridge - Svalbard
    2019.12.09
    In its ninth year, Operation IceBridge operated three missions out of a base in Svalbard, Norway. The expanded reach across the Arctic Basin provided critical data to IceBridge's scientific mission.
  • Operation IceBridge - Western Greenland
    2019.12.09
    NASA’s Operation IceBridge images Earth’s polar ice in unprecedented detail to better understand processes that connect the polar regions with the global climate system. IceBridge utilizes a highly specialized fleet of research aircraft and the most sophisticated suite of innovative science instruments ever assembled to characterize annual changes in thickness of sea ice, glaciers, and ice sheets. In addition, IceBridge collects critical data used to predict the response of earth’s polar ice to climate change and resulting sea-level rise. In 2019, IceBridge was based out of Kangerlussuaq in western Greenland, surveying both sea ice and land ice. Flight lines include survey lines over the Jakobshavn and Kangerlussuaq glaicers, as well as surveyed several IceSat2 ground tracks in southern Greenland. The flights also revealed a startling amount of early spring melt ponts on Greenland's ice sheet.
  • Operation IceBridge - Greenland Sea Ice
    2019.12.09
    Arctic sea ice occupies an ocean basin mostly enclosed by land. Because there is no landmass at the North Pole, sea ice extends all the way to the pole, making the ice subject to the most extreme oscillations between wintertime darkness and summertime sunlight. Likewise, because the ocean basin is surrounded by land, ice has less freedom of movement to drift into lower latitudes and melt. Arctic sea ice generally reaches its maximum extent each March and its minimum extent each September.
  • Operation IceBridge - Spring Svalbard Sea Ice
    2019.12.09
    On April 7, 2017, Operation IceBridge flew the distinct Zig Zag East mission. This flight started in the rugged fjords of Svalbard, passed over hundreds of miles of sea ice en route to the North Pole, flew through the narrow Nares Strait, and finally returned the team back to Thule Air Base in Greenland. The clip below shows dramatic sea ice encountered as the mission crossed the Fram Strait (the primary pathway that sea ice from the Arctic Basin gets out to warmer ocean). This type of sea ice is commonly referred to as broken pack ice.
  • Operation IceBridge - Thule Ice Sheet Scenics
    2019.12.09
    Frozen sea ice outside of the Thule Air Base in Greenland provided project scientists a chance to get up close to locked icebergs and other features.
  • Operation IceBridge - Western Greenland Sea Ice
    2019.12.09
    NASA’s Operation IceBridge images Earth’s polar ice in unprecedented detail to better understand processes that connect the polar regions with the global climate system. IceBridge utilizes a highly specialized fleet of research aircraft and the most sophisticated suite of innovative science instruments ever assembled to characterize annual changes in thickness of sea ice, glaciers, and ice sheets. In addition, IceBridge collects critical data used to predict the response of earth’s polar ice to climate change and resulting sea-level rise. In 2019, IceBridge was based out of Kangerlussuaq in western Greenland, surveying both sea ice and land ice.

Antarctic

IceBridge conducted missions over Antarctica from a base of operations either in Punta Arenas, Chile, Ushuaia, Argentina, Hobart, Tasmania, or New Zealand.

The surveys were conducted from NASA’s DC-8 airborne science laboratory and periodically NASA's GV, or P3-Orion aircraft. The DC-8, managed by NASA’s Armstrong Flight Research Center in Palmdale, California, carried IceBridge’s full instrument suite.

  • Operation Ice Bridge - Pine Island Glacier
    2019.12.09
    Pine Island Glacier is one of many outlet glaciers around the perimeter of Antarctica, but observations have shown that this glacier is worth extra attention. It is, along with neighboring Thwaites Glacier, one of the main pathways for ice entering the Amundsen Sea from the West Antarctic Ice Sheet and one the fastest-retreating glaciers in Antarctica. Collectively, the region contains enough vulnerable ice to raise global sea level by 1.2 meters (4 feet). Operation IceBridge routinely surveyed the glacier during its annual missions over the continent.
  • Operation Ice Bridge - Antarctic Airborne Topographic Mapper
    2019.11.22
    The Airborne Topographic Mapper (ATM), developed at NASA Wallops Flight Facility in Wallops Island, Va., is a scanning laser altimeter that measures changes in ice surface elevation. It accomplishes this by reflecting lasers off the ice surface and measuring the time it takes light to return to the aircraft, usually flying between 1000 and 2000 feet above the ground. By combining this timing data with detailed information about the aircraft’s position and attitude from GPS and inertial navigation systems, ATM can measure topography to an accuracy of as small as four inches. By flying ATM over the same swath of ground previously covered by ICESat, researchers can maintain a record of changes. In addition, the precise data from ATM’s navigation system can be fed to pilot displays in the cockpit or even electronically sent to the automatic pilot system, keeping the aircraft aligned with the planned survey track. This keeps the aircraft along the planned ATM survey swath and also benefits the other IceBridge instruments by minimizing aircraft roll and horizontal acceleration.
  • Operation IceBridge - Antarctic Transits
    2019.12.09
    NASA is carrying out its sixth consecutive year of Operation IceBridge research flights over Antarctica in 2014 to study changes in the continent’s ice sheet, glaciers and sea ice. For several weeks, researchers flew aboard NASA’s DC-8 research aircraft out of Punta Arenas, Chile.
  • Operation IceBridge - Crew Activity Oboard
    2019.12.09
    NASA's P-3B and DC-8 airborne laboratories have been the workhorses of Operation IceBridge. These aircraft house several sophisticated instruments for measuring snow depth, ice elevation and thickness, surface temperature, bed topography and other characteristics of sea ice, ice sheets and glaciers.
  • Operation IceBridge - Instrument Panels
    2019.11.25
    NASA's P-3B and DC-8 airborne laboratories have been the workhorses of Operation IceBridge. These aircraft house several sophisticated instruments for measuring snow depth, ice elevation and thickness, surface temperature, bed topography and other characteristics of sea ice, ice sheets and glaciers. The airborne laboratories have been joined by other aircraft, such as NASA's C-130 Hercules, King Air B-200 and HU-25C Falcon, the Gulfstream G-V owned by the National Science Foundation and operated by NCAR’s Research Aviation Facility, the University of Texas Institute for Geophysics' (UTIG) chartered Kenn Borek Basler BT-67, and a variety of small planes used by researchers from the University of Alaska-Fairbanks (UAF). These aircraft increase the number of instruments IceBridge can field at one time, greatly expand the geographic area covered and add a higher-altitude perspective on polar ice.
  • Operation IceBridge - A68 Ice Island
    2019.12.09
    Operation IceBridge, NASA’s longest-running aerial survey of polar ice, flew over the northern Antarctic Peninsula on Oct. 16, 2018. During the survey, designed to assess changes in the ice height of several glaciers draining into the Larsen A, B and C embayments, IceBridge senior support scientist Jeremy Harbeck spotted a very sharp-angled, tabular iceberg floating among sea ice just off of the Larsen C ice shelf.
  • Operation IceBridge - Antarctic Fissures
    2019.12.09
    Ice shelves are the floating parts of ice streams and glaciers, and they buttress the grounded ice behind them; when ice shelves collapse, the ice behind accelerates toward the ocean, where it then adds to sea level rise.
  • Operation IceBridge - Ice Shelf
    2019.12.09
    Larsen C, a floating platform of glacial ice on the east side of the Antarctic Peninsula, is the fourth-largest ice shelf on the coast of Antarctica.
  • Operation IceBridge - Antarctic Icebergs
    2019.12.09
    Tabular icebergs float near the Weddell Sea in Antarctica

Alaska

In Alaska, 5 percent of the land is covered by glaciers that are losing a lot of ice and contributing to sea level rise. To monitor these changes, a small team of NASA-funded researchers has been flying scientific instruments on a bright red, single-engine plane since spring 2009. While scientists at the Goddard Space Flight Center managed the two larger yearly field campaigns in the Arctic and Antarctica, monitoring Alaskan glaciers fell on a smaller team based at the University of Fairbanks, Alaska.
  • Operation IceBridge - Alaskan Glaciers
    2019.12.09
    In Alaska, 5 percent of the land is covered by glaciers that are losing a lot of ice and contributing to sea level rise. To monitor these changes, a small team of NASA-funded researchers has been flying scientific instruments on a bright red, single-engine plane since spring 2009. While scientists at the Goddard Space Flight Center managed the two larger yearly field campaigns in the Arctic and Antarctica, monitoring Alaskan glaciers fell on a smaller team based at the University of Fairbanks, Alaska.
  • Operation IceBridge - Alaskan Landscape
    2019.12.09
    In Alaska, 5 percent of the land is covered by glaciers that are losing a lot of ice and contributing to sea level rise. To monitor these changes, a small team of NASA-funded researchers has been flying scientific instruments on a bright red, single-engine plane since spring 2009. While scientists at the Goddard Space Flight Center managed the two larger yearly field campaigns in the Arctic and Antarctica, monitoring Alaskan glaciers fell on a smaller team based at the University of Fairbanks, Alaska.
  • Operation IceBridge - Alaskan Operations
    2019.12.09
    In Alaska, 5 percent of the land is covered by glaciers that are losing a lot of ice and contributing to sea level rise. To monitor these changes, a small team of NASA-funded researchers has been flying scientific instruments on a bright red, single-engine plane since spring 2009. While scientists at the Goddard Space Flight Center managed the two larger yearly field campaigns in the Arctic and Antarctica, monitoring Alaskan glaciers fell on a smaller team based at the University of Fairbanks, Alaska.
  • Flying Alaskan Glaciers
    2019.03.29
    Flying low over some of the most dramatic landscapes on the planet, a cadre of scientists and pilots have been measuring changes in Alaskan glaciers as part of NASA’s Operation IceBridge for almost a decade. The team has seen significant change in ice extent and thickness over that time. Data from the mission was used in a 2015 study that put numbers on the loss of Alaskan glaciers: 75 billion tons of ice every year from 1994 to 2013. Last summer, Chris Larsen and Martin Truffer, both of the University of Alaska Fairbanks, flew with University of Arizona's Jack Holt and University of Texas student Michael Christoffersen.

Data Visualizations

Throughout the mission, NASA's Scientific Visualization Studio worked closely with mission scientists to create a suite of visualizations, animations, and images in order to promote a greater understanding of data gathered during OIB campaigns.
  • Operation IceBridge Flight Lines 2009-2019
    2019.12.12
    For ten years from 2009 to 2019, the planes of NASA’s Operation IceBridge flew above the Arctic and Antarctic, gathering data on the height, depth, thickness, flow and change of sea ice, glaciers, and ice sheets. Designed to bridge the gap between NASA’s two Ice, Cloud, and land Elevation Satellites, ICESat and ICESat-2, IceBridge made its final flight in November 2019, one year after ICESat-2’s successful launch. The fleet of aircraft carried more than a dozen instruments, from ice-penetrating radar and elevation-mapping lasers to optical and infrared cameras. This visualization shows the flight lines of each yearly campaign from 2009 to 2019, created from navigational data obtained from the flights.
  • Greenland View of Three Simulated Greenland Ice Sheet Response Scenarios: 2008 - 2300
    2019.06.19
    The Greenland Ice Sheet holds enough water to raise the world’s sea level by over 7 meters (23 feet). Rising atmosphere and ocean temperatures have led to an ice loss equivalent to over a centimeter increase in global mean sea-level between 1991 and 2015. Large outlet glaciers, rivers of ice moving to the sea, drain the ice from the interior of Greenland and cause the outer margins of the ice sheet to recede. Improvements in measuring the ice thickness in ice sheets is enabling better simulation of the flow in outlet glaciers, which is key to predicting the retreat of ice sheets into the future. Recently, a simulation of the effects of outlet glacier flow on ice sheet thickness coupled with improved data and comprehensive climate modeling for differing future climate scenarios has been used to estimate Greenland’s contribution to sea-level over the next millennium. Greenland could contribute 5–34 cm (2-13 inches) to sea-level by 2100 and 11–162 cm (4-64 inches) by 2200, with outlet glaciers contributing 19–40 % of the total mass loss. The analysis shows that uncertainties in projecting mass loss are dominated by uncertainties in climate scenarios and surface processes, followed by ice dynamics. Uncertainties in ocean conditions play a minor role, particularly in the long term. Greenland will very likely become ice-free within a millennium without significant reductions in greenhouse gas emissions. Three visualizations of the evolution of the Greenland Ice Sheet between 2008 and 2300 based on three different climate scenarios are shown below. Each scenario is described briefly in the caption under each visualization. Each of the three visualizations are provided with a date and colorbar as well as without. The regions shown in a violet color are exposed areas of the Greenland bed that were covered by the ice sheet in 2008. The data sets used for these animations are the control (“CTRL”) simulations and were produced with the open-source Parallel Ice Sheet Model (www.pism-docs.org). All data sets for this study are publicly available at https://arcticdata.io (doi:10.18739/A2Z60C21V).
  • Jakobshavn Regional View of Three Simulated Greenland Ice Sheet Response Scenarios: 2008 - 2300
    2019.06.19
    The Greenland Ice Sheet holds enough water to raise the world’s sea level by over 7 meters (23 feet). Rising atmosphere and ocean temperatures have led to an ice loss equivalent to over a centimeter increase in global mean sea-level between 1991 and 2015. Large outlet glaciers, rivers of ice moving to the sea, drain the ice from the interior of Greenland and cause the outer margins of the ice sheet to recede. Improvements in measuring the ice thickness in ice sheets is enabling better simulation of the flow in outlet glaciers, which is key to predicting the retreat of ice sheets into the future. Recently, a simulation of the effects of outlet glacier flow on ice sheet thickness coupled with improved data and comprehensive climate modeling for differing future climate scenarios has been used to estimate Greenland’s contribution to sea-level over the next millennium. Greenland could contribute 5–34 cm (2-13 inches) to sea-level by 2100 and 11–162 cm (4-64 inches) by 2200, with outlet glaciers contributing 19–40 % of the total mass loss. The analysis shows that uncertainties in projecting mass loss are dominated by uncertainties in climate scenarios and surface processes, followed by ice dynamics. Uncertainties in ocean conditions play a minor role, particularly in the long term. Greenland will very likely become ice-free within a millennium without significant reductions in greenhouse gas emissions. Three visualizations of the evolution of the Jakobshavn region of the Greenland Ice Sheet between 2008 and 2300 based on three different climate scenarios are shown below. Each scenario is described briefly in the caption under each visualization. Each of the three visualizations are provided with a date, colorbar and a distance scale as well as without. The regions shown in a violet color are exposed areas of the Greenland bed that were covered by the ice sheet in 2008. The data sets used for these animations are the control (“CTRL”) simulations and were produced with the open-source Parallel Ice Sheet Model (www.pism-docs.org). All data sets for this study are publicly available at https://arcticdata.io (doi:10.18739/A2Z60C21V).
  • Three Simulated Greenland Ice Sheet Response Scenarios: 2008 - 2300
    2019.06.19
    The Greenland Ice Sheet holds enough water to raise the world’s sea level by over 7 meters (23 feet). Rising atmosphere and ocean temperatures have led to an ice loss equivalent to over a centimeter increase in global mean sea-level between 1991 and 2015. Large outlet glaciers, rivers of ice moving to the sea, drain the ice from the interior of Greenland and cause the outer margins of the ice sheet to recede. Improvements in measuring the ice thickness in ice sheets is enabling better simulation of the flow in outlet glaciers, which is key to predicting the retreat of ice sheets into the future. Recently, a simulation of the effects of outlet glacier flow on ice sheet thickness coupled with improved data and comprehensive climate modeling for differing future climate scenarios has been used to estimate Greenland’s contribution to sea-level over the next millennium. Greenland could contribute 5–34 cm (2-13 inches) to sea-level by 2100 and 11–162 cm (4-64 inches) by 2200, with outlet glaciers contributing 19–40 % of the total mass loss. The analysis shows that uncertainties in projecting mass loss are dominated by uncertainties in climate scenarios and surface processes, followed by ice dynamics. Uncertainties in ocean conditions play a minor role, particularly in the long term. Greenland will very likely become ice-free within a millennium without significant reductions in greenhouse gas emissions. Three visualizations of the evolution of the Jakobshavn region of the Greenland Ice Sheet between 2008 and 2300 based on three different climate scenarios are shown below. The camera zooms in slowly as the ice sheet retreats and pulls out to a view of the entire ice sheet in the year 2300. Each scenario is described briefly in the caption under each visualization. Each of the three visualizations are provided with a date, colorbar and a distance scale as well as without. The regions shown in a violet color are exposed areas of the Greenland bed that were covered by the ice sheet in 2008. The data sets used for these animations are the control (“CTRL”) simulations and were produced with the open-source Parallel Ice Sheet Model (www.pism-docs.org). All data sets for this study are publicly available at https://arcticdata.io (doi:10.18739/A2Z60C21V).
  • A possible second large subglacial impact crater in northwest Greenland
    2019.02.11
    It is increasingly rare to find new large impact craters on Earth, let alone such craters buried beneath ice. This study by MacGregor et al. describes a possible impact crater buried beneath two kilometers of ice in northwest Greenland. The circular structure is more than 36 kilometers wide, and both its shape and other geophysical properties are consistent with an impact origin. If eventually confirmed as an impact crater, it would be only the second found beneath either of Earth’s ice sheets. The first was the Hiawatha impact crater, which is also in northwest Greenland and only 183 kilometers away from this new structure, so this team also evaluated whether these two craters could be related. They are similarly sized, but the candidate second crater appears more eroded and ice above it is much less disturbed than above the Hiawatha impact crater. Statistical analysis of the frequency of two unrelated but nearby large impacts indicates that it is improbable but not impossible that this pair is unrelated. This study expands knowledge of the impact history of the Earth and raises the question as to how many other impact craters buried beneath ice have yet to be found.
  • Operation IceBridge 2011 Arctic Flight Paths and Change in Elevation Data over Greenland
    2011.03.28
    With the aircraft resources of NASA's Airborne Sciences Program, Operation IceBridge is taking to the sky to ensure a sustained, critical watch over Earth's polar regions. Flight lines (black) are shown for the 2011 campaign over Arctic sea ice and Greenland's land ice. Many flights target outlet glaciers along the coast where NASA's Ice, Cloud and land Elevation Satellite (ICESat) shows significant thinning. Blue and purple colors, respectively, indicate moderate to large thinning. Gray and yellow, respectively, indicate slight to moderate thickening. Since its launch in January 2003, the ICESat elevation satellite has been measuring the change in thickness of ice sheets. This image of Greenland shows the changes in elevation over the Greenland ice sheet between 2003 and 2006.
  • West Antarctic Glacier Ice Flows and Elevation Change
    2011.11.02
    This animation shows glacier changes detected by ATM, ICESat and ice bridge data in the highly dynamic Amundsen Embayment of West Antarctica. We know that ice speeds in this area have increased dramatically from the late 1990s to the present as the ice shelves in this area have thinned and the bottom of the ice has lost contact with the bed beneath. As the ice has accelerated, ice upstream of the coast must be stretched more vigorously, causing it to thin. NASA-sponsored aircraft missions first measured the ice surface height in this region in 2002, followed by ICESat data between 2002 and 2009. Ice Bridge aircraft have measured further surface heights in 2009 and 2010, and these measurements continue today. Integrating these altimetry sources allows us to estimate surface height changes throughout the drainage regions of the most important glaciers in the region. We see large elevation changes at the coast on Thwaites glacier, at the center of the images, and large and accelerating elevation changes extending inland from the coast on Pine Island and Smith glaciers, to the left and right of the images, respectively. The changes on Pine Island and Smith glaciers mark these as potential continuing sources of ice to the sea, and they have been surveyed in 2011 by Ice Bridge aircraft and targeted for repeat measurements in coming years.
  • Laser Radar Animation
    2010.04.05
    Laser and radar instruments aboard NASA aircraft provide measurements of the snow and ice surface and down to the bedrock under the ice. Lasers, with a shorter wavelength, measure the surface elevation of the snow or ice to within a fraction of an inch. Radar instruments utilize a longer wavelength and can penetrate the ice to "see" below the surface, providing a profile of ice characteristics and also the shape of the bedrock. This information is critical for understanding how and why the world's biggest ice masses are changing.
  • Greenland's Mega Canyon (narrated video)
    2013.08.29
    Hidden for all of human history, a 460 mile long canyon has been discovered below Greenland's ice sheet. Using radar data from NASA's Operation IceBridge and other airborne campaigns, scientists led by a team from the University of Bristol found the canyon runs from near the center of the island northward to the fjord of the Petermann Glacier.

    A large portion of the data was collected by IceBridge from 2009 through 2012. One of the mission's scientific instruments, the Multichannel Coherent Radar Depth Sounder, operated by the Center for the Remote Sensing of Ice Sheets at the University of Kansas, can see through vast layers of ice to measure its thickness and the shape of bedrock below.

    This is a narrated version of an visualization that can be found, along with more detailed information, at

    Greenland's Mega-Canyon beneath the Ice Sheet (#4097).

  • Greenland Ice Sheet Stratigraphy
    2015.01.23
    For nearly a century, scientists have been studying the form and flow of the Greenland Ice Sheet. They have measured the change in the elevation of the surface over time using satellites. They have drilled ice cores in the field to reveal a record of what the past climate was like. They have flown aircraft over the surface of the ice sheet laden with instruments to gleen information about the interior of the ice sheet and the bedrock below. Now a new analysis of this data has revealed a three dimensional map of the age of the ice sheet. This visualization shows this new 3D age map of the Greenland Ice Sheet, explains how it was created and describes the three distinct periods of climate that are evident within the ice sheet. More information is available here.
  • Operation IceBridge Tracks over the Helheim Glacier in Greenland
    2016.08.31
    Operation Ice Bridge (OIB) has been flying annual airborne missions over the Helheim Glacier in Greenland since 1997. These missions record the elevation of the glacier along a long, thin track near the middle of the glacier. This record of heights helps scientists see how the glacier has changed over the years. This visualization shows OIB tracks from each year in sequence. The camera then moves to the side to compare the ice profiles on a graph. The track profiles are shown to scale (i.e., no exaggeration) until they are compared on the graph where they are exaggerated 10 times to help see the changes. The initial camera for this animation matches the end of the Helheim visualization (#4348). Image layers are included for each track and the graph for those wishing to create different composites.