ICESat-2

The Ice, Cloud and land Elevation Satellite-2 will measure the height of Earth from space, creating a record of the planet’s elevation in unprecedented detail and precision. With high-resolution data from ICESat-2’s laser altimeter, scientists will track changes to Earth’s polar ice caps – regions that are a harbinger of warming temperatures worldwide. The mission will also take stock of forests, map ocean surfaces, track the rise of cities and measure everything in between. ICESat-2 continues key elevation observations begun by ICESat-1 (2003 to 2009) and Operation IceBridge (2009 through present), to provide a portrait of change in the beginning of the 21st century.

For more information, please visit the ICESat-2 website.

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Data Visualizations

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    ICESat-2 Sea Ice Thickness 2023
    2023.04.25
    One of the big challenges in polar science is measuring the thickness of the floating sea ice that blankets the Arctic and Southern Oceans. Newly formed sea ice might be only a few inches thick, whereas sea ice that survives several winter seasons can grow to several feet in thickness (over ten feet in some places). Sea ice thickness is typically estimated by first measuring sea ice freeboard - how much of the floating ice can be observed above sea level. Sea ice floats slightly above sea level because it is less dense than water. NASA’s ICESat-2 satellite measures the Earth’s surface height by firing green laser pulses towards Earth and timing how long it takes for those laser pulses to reflect back to the satellite. Ice freeboard is calculated by differencing the heights of the ice surface and areas of open water next to the ice. Additional information including the depth and density of the snow layer on top of the ice is needed to convert this freeboard measurement to sea ice thickness. New state-of-the-art snow accumulation models have been developed to provide this extra data in preparation for the launch of ICESat-2. The very high precision of the ICESat-2 laser has enabled us for to measure the thickness of very thin sea ice for the first time. As the Arctic warms rapidly it is becoming increasingly dominated by a younger and thinner ice cover, making these new measurements extremely invaluable for understanding our changing polar regions.
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    ICESat-2 Sea Ice Thickness 2022
    2022.04.08
    One of the big challenges in polar science is measuring the thickness of the floating sea ice that blankets the Arctic and Southern Oceans. Newly formed sea ice might be only a few inches thick, whereas sea ice that survives several winter seasons can grow to several feet in thickness (over ten feet in some places). Sea ice thickness is typically estimated by first measuring sea ice freeboard - how much of the floating ice can be observed above sea level. Sea ice floats slightly above sea level because it is less dense than water. NASA’s ICESat-2 satellite measures the Earth’s surface height by firing green laser pulses towards Earth and timing how long it takes for those laser pulses to reflect back to the satellite. Ice freeboard is calculated by differencing the heights of the ice surface and areas of open water next to the ice. Additional information including the depth and density of the snow layer on top of the ice is needed to convert this freeboard measurement to sea ice thickness. New state-of-the-art snow accumulation models have been developed to provide this extra data in preparation for the launch of ICESat-2. The very high precision of the ICESat-2 laser has enabled us for to measure the thickness of very thin sea ice for the first time. As the Arctic warms rapidly it is becoming increasingly dominated by a younger and thinner ice cover, making these new measurements extremely invaluable for understanding our changing polar regions.
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    ICESat-2 Land Ice Height Change
    2022.05.15
    NASA’s ICESat-2 satellite measures the elevation of Earth’s surfaces – and two data products from the mission map the height of Antarctic and Greenland ice sheets, as well as how those ice sheets change over time. The ICESat-2 ATL14 data product provides a reference ice sheet surface corresponding to the ice sheet elevation in April 2019, while ATL15 provides elevation changes to that surface through time. These products are re-generated every 91 days, which is how long it takes ICESat-2 to complete its 1,387 unique orbits and collect a complete grid of measurements. Every time ATL14 and 15 are regenerated, all of the data over the life of the mission is used to improve the April 2019 standard, and best represent how the ice sheets are changing. ATL14 is posted at 100m resolution, and ATL15 is posted at 1 km resolution at one month time resolution.
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    Global Snow Cover and Sea Ice Cycle at Both Poles
    2022.04.22
    Global snow cover and sea ice waxes and wanes with the seasons, as the axial tilt of the Earth with respect to the Sun oscillates throughout the year. As can be seen in this visualization, the cycles of ice and snow are about six months out of phase between the Northern and Southern Hemispheres, since the north is tilted towards the Sun when the nouth is tilted away, and vice versa.
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    The Reference Elevation Model of Antarctica (REMA)
    2022.03.18
    The Reference Elevation Model of Antarctica (REMA) provides the first, high resolution (8-meter) terrain map of nearly the entire continent. REMA is constructed from hundreds of thousands of individual stereoscopic Digital Elevation Models (DEM) extracted from pairs of submeter (0.32 to 0.5 m) resolution DigitalGlobe satellite imagery, including data from WorldView-1, WorldView-2, and WorldView-3, and a small number from GeoEye-1, acquired between 2009 and 2017, with most collected in 2015 and 2016, over the austral summer seasons (mostly December to March). Each individual DEM was vertically registered to satellite altimetry measurements from Cryosat-2 and ICESat, resulting in absolute uncertainties of less than 1 m over most of its area, and relative uncertainties of decimeters. This visualization compares the spatial resolution of REMA with DEM data from RADARSAT.
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    Annual Arctic Sea Ice Minimum 1979-2021 with Area Graph
    2022.05.05
    Satellite-based passive microwave images of the sea ice have provided a reliable tool for continuously monitoring changes in the Arctic ice since 1979. Every summer the Arctic ice cap melts down to what scientists call its "minimum" before colder weather begins to cause ice cover to increase. This graph displays the area of the minimum sea ice coverage each year from 1979 through 2021. In 2021, the Arctic minimum sea ice covered an area of 4.13 million square kilometers (1.6 million square miles). This visualization shows the expanse of the annual minimum Arctic sea ice for each year from 1979 through 2021 as derived from passive microwave data. A graph overlay shows the area in million square kilometers for each year's minimum day.
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    Arctic Sea Ice Maximum 2022
    2022.03.22
    After growing through the fall and winter, sea ice in the Arctic appears to have reached its annual maximum extent. The image above shows the ice extent—defined as the total area in which the ice concentration is at least 15 percent—at its 2022 maximum, which occurred on February 25, tying with 2015 for the third earliest maximum on record. On this day the extent of the Arctic sea ice cover peaked at 14.88 million square kilometers (5.75 million square miles), making it the tenth lowest yearly maximum extent on record.
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    Earth Observing Fleet (December 2021)
    2021.12.13
    This animation shows the orbits of NASA's fleet of Earth observing spacecraft that are considered operational as of December 2021. Note that Landsat 9 is still completing the commissioning period and is expected to be declared operational in mid-January 2022. The clouds used in this version are from a high resolution GEOS model run at 10 minute time steps interpolated down to the per-frame level. Changes to this version include: removal of Landsat-7 and addition of Landsat-9.
    Spacecraft included: • Aqua • Aura • CALIPSO: Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation • CYGNSS-1: Cyclone Global Navigation Satellite System 1 • CYGNSS-2: Cyclone Global Navigation Satellite System 2 • CYGNSS-3: Cyclone Global Navigation Satellite System 3 • CYGNSS-4: Cyclone Global Navigation Satellite System 4 • CYNGSS-5: Cyclone Global Navigation Satellite System 5 • CYGNSS-6: Cyclone Global Navigation Satellite System 6 • CYGNSS-7: Cyclone Global Navigation Satellite System 7 • CYGNSS-8: Cyclone Global Navigation Satellite System 8 • Cloudsat • GPM: Global Precipitation Measurement • GRACE-FO-1: Gravity Recovery and Climate Experiment Follow On-1 • GRACE-FO-2: Gravity Recovery and Climate Experiment Follow On-2 • ICESat-2 • ISS: International Space Station • Landsat 8 • Landsat 9 • OCO-2: Orbiting Carbon Observatory-2 • SMAP: Soil Moisture Passive Active • Suomi NPP: Suomi National Polar-orbiting Partnership • Sentinel-6 Michael Freilich • Terra
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    Studying vegetation canopy with ICESAT-2
    2021.09.17
    Although the primary mission goal of ICESat-2 is to monitor changes in the cryosphere, ICESat-2 also collects elevation data over the Earth’s land surfaces providing geodetic measurements to support a wide range of terrestrial applications. In the temperate and tropical regions, ranging measurements from ICESat-2 are used to produce estimates of terrain and canopy heights of the worlds’ forests. The density and vertical distribution of the returned photons from within the canopy can be utilized to infer information regarding forest biomass, canopy volume, habitat mapping, biodiversity, and parameterization of land-climate models. The ICESat-2 satellite is in a polar orbit (92 degrees) and is the only space based laser altimeter capable of collecting ranging measurements over all land surfaces. The instrument onboard ICESat-2 is the Advanced Topographic Laser Altimeter System (ATLAS) and ATLAS is sensitive to detect single photons reflected from the surface. ATLAS uses a 532 nm laser that fires at a rate of 10 kHz (or every 70 cm on the Earth’s surface) which facilitates high spatial resolution in the along-track direction. A diffractive optical element splits the ATLAS laser into 6 beams; 3 beam pairs approximately 3 km apart. Each beam pair is comprised of a strong beam and weak beam. Because ATLAS is sensitive at the photon level, solar background noise can present a challenge in the analysis or photon counting data. ICESat-2 is a profiling lidar and a result of the beam configuration is high resolution in the along-track direction; however gaps exist between beams. In the mid-latitudes, ICESat-2 operates in vegetation mode which consists of off-nadir pointing the satellite to a different ground track each 91-day repeat cycle. Thus, rather than repeating an orbit every 91 days, ICESat-2 will point to a different location on the Earth to improve the spatial sampling. Over a period of two years, this series of off-pointing maneuvers has reduced the distance between tracks at the equator from 29 km to approximately 2 km. As the mission continues through time with more off-pointing maneuvers, the distance between ground tracks will continue to decrease.
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    Variability of Water Storage in Global Hydrological Basins
    2021.03.03
    Knowing the extent of human influence on the global hydrological cycle is essential for the sustainability of freshwater resources on Earth. However, a lack of water level observations for the world’s ponds, lakes, and reservoirs has limited quantification of reservoir (human-managed) versus natural changes to surface water storage. In this study, scientists used data from NASA's ICESat-2 satellite laser altimeter to quantify global variability in water level over 227,386 water bodies from October 2018 to July 2020. By combining this dataset with a global database of human-managed reservoirs, the study found that 57% of seasonal water storage variability occurs in human-managed reservoirs. Global maps of the results organized by hydrologic basin reveal that natural variability in surface water level is greatest in tropical basins like the Amazon and the Congo and lowest in northern and Arctic areas such as Northern Canada and Alaska. In contrast, human-management of surface water storage in arid and semi-arid regions like the Western US, Middle East, Southern Africa and Australia, where human influence drives nearly 100% of seasonal storage variability. Overall, the finding that humans are responsible for the majority of seasonal surface water storage variability shows that we are now a key regulator of the water cycle. As economic development, population growth, and climate change continue to pressure global water resources in the future, measurements from satellites like ICESat-2 will continue to provide vital information about how humans are managing freshwater resources worldwide. This animation uses data from the study to visualize two quantities: the variability of water level, and the variability of the percent of water storage from man-made reservoirs.
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    NASA Laser and ESA Radar Sync Up for Sea Ice
    2020.07.16
    One of the big challenges in polar science is measuring the thickness of the floating sea ice that blankets the Arctic and Southern Oceans. Newly formed sea ice might be only a few inches thick, whereas sea ice that survives several winter seasons can grow to several feet in thickness (over ten feet in some places). Sea ice thickness is typically estimated by first measuring sea ice freeboard - how much of the floating ice can be observed above sea level. Sea ice floats slightly above sea level because it is less dense than water. An additional complexity is that snow fall on sea ice pushes the floating ice downward and has a lower density than the sea ice. In order to estimate the sea ice thickness, some accommodation for the overlying snow must be made. NASA’s ICESat-2 satellite measures the Earth’s surface height by firing green laser pulses towards Earth and timing how long it takes for those laser pulses to reflect back to the satellite. The laser light reflects off the top of the snow layer on top of the sea ice. In contrast, the European Space Agency’s CryoSat-2 mission uses radar waves to measure height. These radar waves penetrate the overlying snow and are reflected off the sea ice, rather than the overlying snow. In July 2020, ESA elected to slightly perturb the orbit of CryoSat-2 to increase the overlap with ICESat-2. Given their different orbit altitudes, the result is a ~3000km stretch of sea ice that is measured by both ICESat-2 and CryoSat-2. By combining data from these two sensors, scientists can measure the snow layer thickness, and produce substantially improved sea ice thickness estimates.
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    Land Ice Height Change Between ICESat and ICESat-2
    2020.04.30
    The future response of the Antarctic Ice Sheet to changes in climate is the single largest source of uncertainty in projections of sea level rise. If the ice sheet melted completely it would raise sea levels by 57 meters, a process that would unfold over millennia. One key to understanding how the ice sheet will respond in the future is to observe and analyze how the ice sheet has reacted to changes in climate over the past decades, where satellites observations are available. One key to understanding ice sheet change is to examine records of elevation change that show where the ice sheet is thinning and thickening due to changing environment. Recent analysis of incredibly precise surface elevations collected by NASA’s ICESat and ICESat-2 satellite laser altimeters reveals complex patters of ice sheet and ice shelf (floating extensions of the ice sheets) change that are the combined consequence of changes in melting by the ocean, changes in precipitation and, changes at the bed of the glacier where the ice sheet slides across the underlying bedrock. The researchers do this my finding locations where tracks of measured elevation intersect, measuring the change in elevation and correct for changes in the average density of the surface using models. Coherent regional patters of elevation change reveal the underlying mechanism responsible causing ice sheet change. One of the most striking features in the data is the Kamb Ice Stream that once flowed rapidly into the Ross Ice Shelf but that stopped flowing due to an increase friction (resistance to flow) likely caused by changes in the availability of liquid water at its base. Strong patters of thinning are visible all along the Amundsen Cost where ice shelves are rapidly thinning in response to increased melting by warm ocean waters. Melting of ice shelves do not directly contribute to changes in sea level, since they are already floating, but they do indirectly impact how fast the grounded ice is able to flow into the ocean. Ice shelves are located at the fronts of the glaciers and help to regulate how fast the ice flows into the ocean. As the ice shelves thin they become less able to hold back the inland ice, causing the grounded glaciers to accelerate and thin. In the East, broad patters of thickening reveal that the East Antarctic Ice Sheet is growing most likely in response to increases in precipitation relative to some unknown time in the past. The thickening is strongest along the coast of Dronning Maud Land where enhanced moisture transport has resulted in increased snowfall. Despite the diversity of gains and losses, losses in the West (208 cubic kilometers of water per year or Gt) greatly outpace Gains (90 Gt per year) in the east resulting in a total Antarctic mass change loss of 118 Gt per year. As the Greenland Ice Sheet responds to warming oceans and atmosphere it has become one of the largest contributors to sea level rise and will continue to be for the foreseeable future. Scientists are working to determine more precisely how much more ice will be lost and when that loss will occur. One key approach to doing this is to analyze changes in the ice sheets elevation over the past decades where satellite observations are available. By finding the intersection of elevation track measurements collected by NASA’s ICESat (2003-2009) and ICESat-2 (2018-) satellite laser altimeters, researchers are able to make very precise measurements of elevation change that can be converted to estimates of mass change after correcting for changes snow density using models. The combination of long time-span between measurements and the high accuracy of NASA’s satellite laser altimeters allows the researchers to make highly detailed maps of mass change that provide insights into the mechanism behind the ice sheets rapid rate of loss. Thinning can be seen around the periphery of the ice sheet where elevations are closest to sea level and rates of surface melting are highest. This pattern is punctuated by localized areas of extreme thinning where large glaciers come into contact with warm ocean waters. Unlike the uniform pattern of low-elevation thinning that is being driven by increased melting due to warmer summer air temperatures, these concentrated areas of thinning occur where outlet glacier have sped up. These glaciers have sped up in response to some combination of retreating ice front position, changes in the slipperiness at the bed of the glacier due to changes in liquid water at the ice-rock interface and due to change in the rate frontal melting due to an increase in the heat content of the ocean waters that come into contact with the glacier front. Juxtaposed on the pattern of rapid thinning along the periphery of the ice sheet is a broad pattern of thickening in the high-elevation interior of the ice sheet. This pattern of thickening suggests that increases in snowfall, relative to sometime in the past, are partly compensating for increased losses due to enhanced melt and accelerated glacier flow. Overall low-elevation losses greatly outpace high-elevation gains resulting in 3200 cubic kilometers of water (Gt) being lost from the ice sheets and entering the oceans, raising global mean sea level by 8.9 mm.
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    Measuring Sea Ice Thickness with ICESat-2
    2019.09.06
    One of the big challenges in polar science is measuring the thickness of the floating sea ice that blankets the Arctic and Southern Oceans. Newly formed sea ice might be only a few inches thick, whereas sea ice that survives several winter seasons can grow to several feet in thickness (over ten feet in some places). Sea ice thickness is typically estimated by first measuring sea ice freeboard - how much of the floating ice can be observed above sea level. Sea ice floats slightly above sea level because it is less dense than water. NASA’s ICESat-2 satellite measures the Earth’s surface height by firing green laser pulses towards Earth and timing how long it takes for those laser pulses to reflect back to the satellite. Ice freeboard is calculated by differencing the heights of the ice surface and areas of open water next to the ice. Additional information including the depth and density of the snow layer on top of the ice is needed to convert this freeboard measurement to sea ice thickness. New state-of-the-art snow accumulation models have been developed to provide this extra data in preparation for the launch of ICESat-2. The very high precision of the ICESat-2 laser has enabled us for to measure the thickness of very thin sea ice for the first time. As the Arctic warms rapidly it is becoming increasingly dominated by a younger and thinner ice cover, making these new measurements extremely invaluable for understanding our changing polar regions.
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    Rink Glacier Multi-Year Surface Elevation Comparison
    2018.09.07
    Since 1993, the Airborne Topographic Mapper or ATM has been monitoring elevation changes of 160 outlet glaciers in Greenland, many of them on an almost annual basis. Rink Glacier in central west Greenland is one example of a 25-year-long time series of elevation changes. In these visualizations, elevation data for each aircraft flight over the glacier are illustrated using spheres 1m in diameter, with each sphere representing a specific measurement. When viewed together, the spheres form sheets defining the observed surface of the glacier for a given year. The spheres are colored by year, and over time we can see how the glacier's elevation changes. Towards the end of the visualization, the study area of the Rink Glacier is compared to the future coverage of the Ice, Cloud and land Elevation Satellite-2 (ICESat-2), as represented by bright green crisscrossing ground tracks.
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    Arctic Sea Ice from March to September 2017
    2017.09.19
    Arctic sea ice appears to have reached its yearly summertime minimum extent for 2017, according to scientists at the NASA-supported National Snow and Ice Data Center (NSIDC) in Boulder, Colo. Observations indicate that on September 13th, ice extent shrunk to the eighth lowest minimum extent in the satellite record, at 4.64 million sq km, or 1.79 million sq mi.

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    ICESat-2 Orbit
    2017.11.03
    ICESat-2 is a spacecraft designed to accurately measure land and ice elevations on Earth. By comparing observations from different times, scientists will be able to study changes in elevations. ICESat-2 will be in a polar orbit which will provide high coverage near the poles where ice elevations are changing relatively quickly. This visualization shows ICESat-2's polar orbit from afar, then closer up. As we get close to the satellite, the 3 pairs of ICESat-2's ATLAS lidar laser beams begin to resolve. A ground track shows ICESat-2's global coverage which repeats about once every 90 days. The ATLAS lidar on ICESat-2 uses 3 pairs of laser beams to measure the earth’s elevation and elevation change. As a global mission, ICESat-2 will collect data over the entire globe, however the ATLAS instrument is optimized to measure land ice and sea ice elevation in the polar regions. For more information on ICESat-2 click here.
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    Minimum Antarctic Sea Ice 2017
    2017.03.22
    This year’s record low annual sea ice minimum of 2.11 million square kilometers was below the previous lowest minimum extent in the satellite record, which occurred in 1997. Antarctic sea ice saw an early maximum extent in 2016, followed by a very rapid loss of ice starting in early September. Since November, daily Antarctic sea ice extent has continuously been at its lowest levels in the satellite record. The ice loss slowed down in February. “There’s a lot of year-to-year variability in both Arctic and Antarctic sea ice, but overall, until last year, the trends in the Antarctic for every single month were toward more sea ice,” said Claire Parkinson, a senior sea ice researcher at Goddard. “Last year was stunningly different, with prominent sea ice decreases in the Antarctic. To think that now the Antarctic sea ice extent is actually reaching a record minimum, that’s definitely of interest.” The images shown here portray the sea ice as it was observed by the AMSR2 instrument onboard the Japanese Shizuku satellite. The opacity of the sea ice is derived from the AMSR2 sea ice concentration. The blueish white color of the sea ice is derived from the AMSR2 89 GHz brightness temperature. In some of the images. The Landsat Image Mosaic of Antarctica is shown over the continent.
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    Operation Icebridge Studies Changes in Greenland's Helheim Glacier
    2017.07.28
    These visualizations show data from the Helheim Glacier in Greenland collected by Pre-Icebridge in 1998 and Operation Icebridge in 2013. Data from both the Airborne Topographic Mapper (ATM) and the Digital Mapping System (DMS) are included. The first visualization shows how the scanner on the aircraft acquired the data, building up a representation of the 3d laser scanned points as we go. Once the calving front from 1998 is revealed, the 2013 data is faded in showing the differences between the years. The dots are colored initially by absolute height with reds higher and blues lower; after the 2013 data is added, the dot colors change to a localized scheme with reds higher than nearby points and blues lower than nearby points. ATM data is added at the end for some context. The second visualization shows the DMS data with ATM data at the 2013 calving front. The DMS data is overlayed onto photogrametrically determined altitudes which don't precisely correspond to the ATM data. The heights of the ATM data are the 'true' heights.
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    Arctic Daily Sea Ice Concentration from Arctic Minimum 2016 to Arctic Maximum 2017
    2017.03.22
    This animation shows the seasonal change in the extent of the Arctic sea ice between the Arctic minimum, September 10, 2016, and Arctic maximum on March 7, 2017. Arctic sea ice appears to have reached a record low wintertime maximum extent, according to scientists at NASA and the NASA-supported National Snow and Ice Data Center (NSIDC) in Boulder, Colo. This winter, a combination of warmer-than-average temperatures, winds unfavorable to ice expansion, and a series of storms halted sea ice growth in the Arctic. This year’s maximum extent, reached on March 7 at 5.57 million square miles (14.42 million square kilometers), is only about 40,000 square miles below the previous record low, which occurred in 2016, The images shown here portray the sea ice as it was observed by the AMSR2 instrument onboard the Japanese Shizuku satellite. The opacity of the sea ice is derived from the AMSR2 sea ice concentration. The blueish white color of the sea ice is derived from the AMSR2 89 GHz brightness temperature. The annual cycle starts with the minimum extent reached on August 31, 2016 and runs through the daily sea ice concentration until the maximum occurs on March 3, 2017. The Arctic’s sea ice maximum extent has dropped by an average of 2.8 percent per decade since 1979, the year satellites started measuring sea ice. The summertime minimum extent losses are nearly five times larger: 13.5 percent per decade. Besides shrinking in extent, the sea ice cap is also thinning and becoming more vulnerable to the action of ocean waters, winds and warmer temperatures.
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    Arctic Sea Ice Minimum Image: September 10, 2016
    2017.07.08
    This image shows the Arctic sea ice on September 10, 2016 when the ice reached its minimum extent. The opacity of the sea ice is derived from the sea ice concentration where it is greater than 15%. The blueish white color of the sea ice is derived the AMSR2 89 GHz brightness temperature.

    The Japan Aerospace Exploration Agency (JAXA) provides many water-related products derived from data acquired by the Advanced Microwave Scanning Radiometer 2 (AMSR2) instrument aboard the Global Change Observation Mission 1st-Water "SHIZUKU" (GCOM-W1) satellite. Two JAXA datasets used in this animation are the 10-km daily sea ice concentration and the 10 km daily 89 GHz Brightness Temperature.

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    Antarctic Sea Ice on August 28, 2016
    2017.07.08
    This is an image of the Antarctic sea ice on August 28, 2016, the date on which the sea ice reached its maximum annual extent. The opacity of the sea ice is determined by the AMSR2 sea ice concentration. The blueish white color of the sea ice is a false color derived from the AMSR2 89 GHz brightness temperature. Over the Antarctic continent, the Landsat Image Mosaic of Antarctica data shown here has a resolution of 240 meters per pixel.
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    Icesat-2 Measurements Over Antarctica (prelaunch)
    2016.11.09
    The ATLAS lidar on ICESat-2 uses 6 laser beams to measure the earth’s elevation and elevation change. As a global mission, ICESat-2 will collect data over the entire globe, however the ATLAS instrument is optimized to measure land ice and sea ice elevation in the polar regions. ICESat-2 reports elevations with respect to a reference surface, called an ellipsoid. In this measurement system, shared by GPS devices, an elevation of zero meters indicates the notional sea level, although tides, wind, and waves can make the actual sea level either greater than or less than zero. The Antarctic ice sheet, shown here, ranges up to 4000m above sea level. Over the course of 91 days, ATLAS will generate 1387 ground tracks across Antarctica for each of it’s 6 beams.
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    The Thermohaline Circulation - The Great Ocean Conveyor Belt
    2009.10.08
    The oceans are mostly composed of warm salty water near the surface over cold, less salty water in the ocean depths. These two regions don't mix except in certain special areas. The ocean currents, the movement of the ocean in the surface layer, are driven mostly by the wind. In certain areas near the polar oceans, the colder surface water also gets saltier due to evaporation or sea ice formation. In these regions, the surface water becomes dense enough to sink to the ocean depths. This pumping of surface water into the deep ocean forces the deep water to move horizontally until it can find an area on the world where it can rise back to the surface and close the current loop. This usually occurs in the equatorial ocean, mostly in the Pacific and Indian Oceans. This very large, slow current is called the thermohaline circulation because it is caused by temperature and salinity (haline) variations.

    This animation shows one of the major regions where this pumping occurs, the North Atlantic Ocean around Greenland, Iceland, and the North Sea. The surface ocean current brings new water to this region from the South Atlantic via the Gulf Stream and the water returns to the South Atlantic via the North Atlantic Deep Water current. The continual influx of warm water into the North Atlantic polar ocean keeps the regions around Iceland and southern Greenland mostly free of sea ice year round.

    The animation also shows another feature of the global ocean circulation: the Antarctic Circumpolar Current. The region around latitude 60 south is the the only part of the Earth where the ocean can flow all the way around the world with no land in the way. As a result, both the surface and deep waters flow from west to east around Antarctica. This circumpolar motion links the world's oceans and allows the deep water circulation from the Atlantic to rise in the Indian and Pacific Oceans and the surface circulation to close with the northward flow in the Atlantic.

    The color on the world's ocean's at the beginning of this animation represents surface water density, with dark regions being most dense and light regions being least dense (see the animation Sea Surface Temperature, Salinity and Density). The depths of the oceans are highly exaggerated to better illustrate the differences between the surface flows and deep water flows. The actual flows in this model are based on current theories of the thermohaline circulation rather than actual data. The thermohaline circulation is a very slow moving current that can be difficult to distinguish from general ocean circulation. Therefore, it is difficult to measure or simulate.

Edited Features

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    Leaders in Lidar
    2023.01.19
    In this series, we dive into the legacy of Goddard's lead role in developing laser altimetry, which has revolutionized the way we map our planet, the Moon and other planets. Each chapter looks at the successes and failures of these lidar instruments, beginning with the Mars Observer Laser Altimeter in the late 1980s, through the current generation of laser altimeters on ICESat-2 and GEDI. Through dozens of interviews and archival footage, the history, challenges and legacy of lidar are uncovered.
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    New Lakes Discovered Under Antarctic Ice with NASA's ICESat-2
    2021.07.07
    Hundreds of meltwater lakes hide deep beneath the expanse of Antarctica’s ice sheet. With a powerful laser altimeter system in space, NASA’s Ice Cloud and land Elevation Satellite-2 (ICESat-2) is helping scientists “see” under the ice.

    For more on the story: https://www.nasa.gov/feature/goddard/2021/nasa-space-lasers-map-meltwater-lakes-in-antarctica-with-striking-precision

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    NASA Satellite Measures the Human Impact in Water Storage
    2021.03.03
    To investigate humans’ impact on freshwater resources, scientists have now conducted the first global accounting of fluctuating water levels in Earth’s lakes and reservoirs – including ones previously too small to measure from space. Scientists used these height measurements to study 227,386 water bodies over 22 months and discovered that, from season to season, the water level in Earth’s lakes and ponds fluctuate on average by about 8.6 inches (0.22 m). At the same time, the water level of human-managed reservoirs fluctuate on average by nearly quadruple that amount – about 34 inches (0.86 m).
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    NASA's ICESat-2 Looks Beyond the Icy Poles
    2020.12.04
    ICESat-2's main science objective is ice, but the mission is also able to measure the heights of other features, including ocean bathymetry, trees and mountain glaciers.
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    NASA Mission Maps 16 Years of Ice Loss
    2020.04.30
    Using the most advanced Earth-observing laser instrument NASA has ever flown in space, scientists have made precise, detailed measurements of how the elevation of the Greenland and Antarctic ice sheets have changed over 16 years. The results provide insights into how the polar ice sheets are changing, demonstrating definitively that small gains of ice in East Antarctica are dwarfed by massive losses in West Antarctica. The scientists found the net loss of ice from Antarctica, along with Greenland’s shrinking ice sheet, has been responsible for 0.55 inches (14 millimeters) of sea level rise between 2003 and 2019 – slightly less than a third of the total amount of sea level rise observed in the world’s oceans.
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    Science on Thin Ice
    2020.01.20
    ICESat-2 Deputy Project Scientist Nathan Kurtz recounts his time on the initial leg of the MOSAiC Arctic expedition. Spearheaded by the Alfred-Wegener-Institut, MOSAiC is the Multidisciplinary drifting Observatory for the Study of Arctic Climate.
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    Photon Phriday
    2019.08.29
    Mount Everest

    Music: "Starlit Entrance," "Oscillator Dreams," Killer Tracks Music

    Complete transcript available.

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    88-South Antarctic Traverse: Year Two
    2019.05.28
    For the second straight year, NASA researchers endured low temperatures, biting winds, and high altitude to conduct another 88-South Traverse. The 470-mile expedition in one of the most barren landscapes on Earth provides the best means of assessment of the accuracy of data collected from space by the Ice Cloud and land Elevation Satellite-2 (ICESat-2). The researchers drove tracked vehicles called PistenBullys, which were instrumented with GPS to collect highly precise elevation data along 88-degrees South, where ICESat-2’s orbits converge. These data were then used to make direct comparisons with ICESat-2 elevation data. With a fast-firing laser instrument, ICESat-2 measures the elevation of ice sheets and tracks how much they change over time. Even small amounts of melt across areas as vast as Greenland or Antarctica can result in large amounts of meltwater contributing to sea level rise. To help document this, ICESat-2's height change measurements will have a precision of less than an inch – ground-truthed, in part, with efforts like this Antarctic campaign. The traverse was funded by NASA, but had substantial logistical support from the National Science Foundation Office of Polar Programs.
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    Trees Around the GLOBE
    2019.04.26
    We live, play and work with trees everywhere around the globe. The Trees Around the GLOBE Student Research Campaign commenced on September 15, 2018 in conjunction with NASA's ICESat-2 satellite launch on the same date at 6:02am PDT. The ICESat-2 satellite uses an on-board laser altimeter system to measure the height of Earth. Measurements of ice sheets, sea ice, trees, bodies of water, mountains are all part of what ICESat-2 measures. The Trees Around the GLOBE Student Research Campaign is a GLOBE Program campaign focusing on tree height - one of the measurements conducted by the ICESat-2 mission. As part of the GLOBE Program, students and teachers from 121 countries can participate in the campaign, share their data around the world, and collaborate with students and teachers to design research projects based on the data collected within GLOBE and from the NASA ICESat-2 Mission. Please visit the campaign website at https://www.globe.gov/web/trees-around-the-globe.

    Tree height is not just a measurement - it is a gateway to understanding many things about the environment. The structure of tree canopies, the 3D arrangement of individual trees, has a huge effect on how ecosystems function and cycle through carbon, water, and nutrients. Scientists from the ICESat-2 Mission will periodically review the tree height data collected by the GLOBE community throughout this campaign. The data will allow scientists to use it as satellite data validation and in potential professional research.

    Trees Around the GLOBE Student Research Campaign.

    Join the GLOBE Program.

    NASA GLOBE Observer for Citizen Science.

    Footage submitted by Ashley and Harald Gundacker, Katherine Lewis, Katie Wright, Emily Fitzgibbons, Leysin American School, Kate Ramsayer, Sol Petit-Scott, Esawiyeh Junior High School for Boys, Lily Wagner, Valerie Casasanto, Marija Krajnik, Katy Mersmann, and Jefferson Beck.

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    New NASA Satellite Reveals Profiles of Ice, Forests and Oceans
    2018.12.11
    Less than three months into its mission, NASA’s Ice, Cloud and land Elevation Satellite-2, or ICESat-2, is already exceeding scientists’ expectations. The satellite is measuring the height of sea ice to within an inch, tracing the terrain of previously unmapped Antarctic valleys, surveying remote ice sheets, and peering through forest canopies and shallow coastal waters.

    With each pass of the ICESat-2 satellite, the mission is adding to datasets tracking Earth’s rapidly changing ice. Researchers are ready to use the information to study sea level rise resulting from melting ice sheets and glaciers, and to improve sea ice and climate forecasts.

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    Mass Balance of Ice Sheets - Antarctica
    2018.09.26
    Antarctica

    Music: "Distant Echoes," Adam Salkeld, Atmosphere Music Ltd. PRS; "Evolution of Life," David Stephen Goldsmith, Atmosphere Music Ltd. PRS

    Complete transcript available.

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    Mass Balance of Ice Sheets - Greenland
    2018.09.26
    Antarctica

    Music: "Distant Echoes," Adam Salkeld, Atmosphere Music Ltd. PRS; "Evolution of Life," David Stephen Goldsmith, Atmosphere Music Ltd. PRS

    Complete transcript available.

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    Countdown to ICESat-2 Launch
    2018.09.06
    NASA is about to launch the agency’s most advanced laser instrument of its kind into space. The Ice, Cloud and land Elevation Satellite-2, or ICESat-2, will provide critical observations of how ice sheets, glaciers and sea ice are changing, leading to insights into how those changes impact people where they live.

    Launch is scheduled for Sept. 15, and as we count down the days, we’re counting up 10 things you should know about ICESat-2.

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    ICESat-2 Elevates Our View of Earth - Short Version
    2017.08.16
    ICESat-2 will provide scientists with height measurements that create a global portrait of Earth’s third dimension, gathering data that can precisely track changes of terrain including glaciers, sea ice, forests and more. The single instrument on ICESat-2 is ATLAS, the Advanced Topographic Laser Altimeter System, will measure melting ice sheets and investigate how this effects sea level rise, investigate changes in the mass of ice sheets and glaciers, estimate and study sea ice thickness, and measure the height of vegetation in forests and other ecosystems worldwide.
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    The 88-South Antarctic Traverse
    2018.03.30
    With extreme cold-weather gear, scientific instruments, and two tank-like snow machines called PistenBullys, NASA scientists began a traverse on December 21 along section of the 88-degree south latitude line in an arc around the South Pole, documenting a new route across the Antarctic ice. The 470-mile expedition in one of the most barren landscapes on Earth provided the best assessment of the accuracy of data collected from space by the Ice Cloud and land Elevation Satellite-2 (ICESat-2), set to launch in 2018. With a fast-firing laser instrument, ICESat-2 will measure the elevation of ice sheets and track how much they change over time. Even small amounts of melt across areas as vast as Greenland or Antarctica can result in large amounts of meltwater contributing to sea level rise. To help document this, ICESat-2's height change measurements will have a precision of less than an inch – ground-truthed, in part, with efforts like this Antarctic campaign. The team will collected precise GPS data of the elevation at 88 degrees south, where ICESat-2’s orbits converge, providing thousands of points where the survey measurements can be compared to satellite data.
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    NASA Scientists Trek the South Pole
    2017.12.14
    With extreme cold-weather gear, scientific instruments, and two tank-like snow machines called PistenBullys, they begin a traverse on Dec. 21 along section of the 88-degree south latitude line in an arc around the South Pole, documenting a new route across the Antarctic ice. The 470-mile expedition in one of the most barren landscapes on Earth will ultimately provide the best assessment of the accuracy of data collected from space by the Ice Cloud and land Elevation Satellite-2 (ICESat-2), set to launch in 2018. With a fast-firing laser instrument, ICESat-2 will measure the elevation of ice sheets and track how much they change over time. Even small amounts of melt across areas as vast as Greenland or Antarctica can result in large amounts of meltwater contributing to sea level rise. To help document this, ICESat-2's height change measurements will have a precision of less than an inch – ground-truthed, in part, with efforts like this Antarctic campaign. The team will collect precise GPS data of the elevation at 88 degrees south, where ICESat-2’s orbits converge, providing thousands of points where the survey measurements can be compared to satellite data.
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    ICESat-2 By the Numbers: 300 Trillion
    2017.11.03
    ICESat-2 is an incredibly precise space laser that features the latest in NASA technology To measure ice heights, engineers have to take ICESat-2’s instrument ATLAS to the extreme – sometimes going big, sometimes going small, but always keeping it precise.
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    ICESat-2 By the Numbers: 532
    2017.11.03
    ICESat-2 is an incredibly precise space laser that features the latest in NASA technology To measure ice heights, engineers have to take ICESat-2’s instrument ATLAS to the extreme – sometimes going big, sometimes going small, but always keeping it precise.
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    ICESat-2 By the Numbers: 90
    2017.11.03
    ICESat-2 is an incredibly precise space laser that features the latest in NASA technology To measure ice heights, engineers have to take ICESat-2’s instrument ATLAS to the extreme – sometimes going big, sometimes going small, but always keeping it precise.
  •
    ICESat-2 By the Numbers: 0.2
    2017.11.03
    ICESat-2 is an incredibly precise space laser that features the latest in NASA technology To measure ice heights, engineers have to take ICESat-2’s instrument ATLAS to the extreme – sometimes going big, sometimes going small, but always keeping it precise.
  •
    ICESat-2 By the Numbers: 1,387
    2017.11.03
    ICESat-2 is an incredibly precise space laser that features the latest in NASA technology To measure ice heights, engineers have to take ICESat-2’s instrument ATLAS to the extreme – sometimes going big, sometimes going small, but always keeping it precise.
  •
    ICESat-2 Elevates Our View of Earth
    2017.08.16
    ICESat-2 will provide scientists with height measurements that create a global portrait of Earth’s third dimension, gathering data that can precisely track changes of terrain including glaciers, sea ice, forests and more. The single instrument on ICESat-2 is ATLAS, the Advanced Topographic Laser Altimeter System, will measure melting ice sheets and investigate how this effects sea level rise, investigate changes in the mass of ice sheets and glaciers, estimate and study sea ice thickness, and measure the height of vegetation in forests and other ecosystems worldwide.
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    ATLAS: Laser Focus
    2015.01.07
    Deputy Systems Engineer Phil Luers explains how the ATLAS transmitter and receiver subsystems come together to calculate the timing of photons, which, in turn, measure the elevation of ice.

    Complete transcript available.

    Music: "Electric Works" by Philippe Lhommet, Koka Media; "From Source to Sea" by Christophe Lebled, Pierre Jacquot, Koka Media.

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    Photon Jump
    2017.03.03
    Pho, a plucky bright green photon of light, must travel from a NASA spacecraft down to Earth and back again to help complete a crucial science mission in this educational short film. The animation was created and produced by media art students from the Savannah College of Art in Design (SCAD) in Georgia, in collaboration with NASA’s Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) mission. Their goal was to communicate the science and engineering of the mission, slated for launch in 2018. ICESat-2, managed by NASA Goddard in Greenbelt, Maryland, will measure the height of a changing Earth, one laser pulse at a time, 10,000 laser pulses a second. ICESat-2 will carry a photon-counting laser altimeter that will allow scientists to measure the elevation of ice sheets, glaciers, sea ice and more - all in unprecedented detail. The workings of this laser helped inspire students to create the character of Pho and plot his adventure. Our planet's frozen and icy areas, called the cryosphere, are a key focus of NASA's Earth science research. ICESat-2 will help scientists investigate why, and how much, our cryosphere is changing in a warming climate. The satellite will also measure heights across Earth's temperate and tropical regions, and take stock of the vegetation in forests worldwide. For more about the mission, visit http://icesat-2.gsfc.nasa.gov.
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    Pho Movie Trailer
    2016.11.21
    The ICESat-2 satellite, which is currently being built and tested at NASA Goddard in Greenbelt, will study Earth in a unique way -- and we have developed a unique education and outreach tool. In Photon Jump, a 3-minute short animation, a brave photon of light named Pho must travel from a NASA spacecraft down to Earth and back again to help complete a crucial science mission. The animation is a partnership between NASA’s ICESat-2 mission and students from the Savannah College of Art and Design. Developed by students and faculty with direct supervision from ICESat’s scientists and engineers, the goal was to create an entertaining and educational short film for a variety of audiences..
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    Laser Focus: The Receiver
    2015.01.07
    Laser Focus: The Receiver

    For complete transcript, click here.

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    ICESat-2 Overview
    2015.07.02
    Animated informational slides designed to introduce the viewer to the ICESat-2 mission and ATLAS instrument.
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    Laser Focus: The Transmitter
    2015.01.07
    ICESat-2's instrument, ATLAS, is designed to measure heights on Earth. ATLAS has three main tasks: transmitting a pattern of six laser beams, collecting the laser photons that return to the satellite after reflecting off Earth, and recording the travel time of those photons. First up – transmitting the laser. In this video, optical engineer Tyler Evans illustrates how the laser is transmitted from the ATLAS instrument to the ground.
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    Intro to LiDAR
    2011.04.14
    Want to know the 3D shape of terrain on another planet? Want to study the height and density of Earth's forests? An amazing tool called LIDAR can help. Learn more in this video!

    This video is presented in stereoscopic 3D for those who can view it. We've included left and right eye clips, a side-by-side version, and an anaglyph (red/blue) version. Download any of them below!

Raw Media for Broadcast

HD broadcast-quality footage of the ICESat-2 spacecraft and ATLAS instrument.

Animations

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    Snow Accumulation
    2018.09.26
    Antarctica

    Music: "Distant Echoes," Adam Salkeld, Atmosphere Music Ltd. PRS; "Evolution of Life," David Stephen Goldsmith, Atmosphere Music Ltd. PRS

    Complete transcript available.

  •
    Mass Balance of Ice Sheets
    2018.09.26
    Antarctica

    Music: "Distant Echoes," Adam Salkeld, Atmosphere Music Ltd. PRS; "Evolution of Life," David Stephen Goldsmith, Atmosphere Music Ltd. PRS

    Complete transcript available.

  •
    ICESat-2 Measures Sea Ice Thickness
    2018.08.22
    Sea ice forms when ocean water freezes, and in the Arctic Ocean forms a brightly reflective cap that helps regulate Earth’s temperature. The ICESat-2 mission will calculate the thickness of sea ice by measuring the freeboard – the difference between the top of sea ice and the ocean surface. From that, computer programs can use the ratio of ice above water to ice below water to calculate the thickness of the floating ice.
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    ICESat-2 Measures Slope
    2015.11.04
    Animation with info key.
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    ICESat-2 Beam Pairs
    2016.02.03
    The ATLAS lidar on ICESat-2 uses 6 laser beams to measure the earth’s elevation and elevation change. By arranging the beams in three pairs of two, scientists can also determine the slope between the two beams, a key component of determining elevation change along the Reference Ground Track. Each time ATLAS collects data along a particular track, onboard software aims the laser beams so that the Reference Ground Track is always between the two beams, as shown in the animation. This allows scientists to combine the elevation and slope information from two different passes to determine elevation change along the Reference Ground Track.
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    Deploy and Beauty Pass
    2014.10.15
    The Ice, Cloud and land Elevation Satellite-2, or ICESat-2, is a laser altimeter that will measure the heights of Earth’s surfaces. With ICESat-2’s high-resolution data, scientists will track changes to Earth’s ice-covered poles, which is witnessing dramatic temperature increases. The mission will also take stock of forests, map ocean surfaces, characterize clouds and more.

    ICESat-2 carries a single instrument called the Advanced Topographic Laser Altimeter System (ATLAS), equipped with a multiple-beam laser, which sends 10,000 pulses of light to the ground each second. A small fraction of the light photons bounce off Earth’s surface and return to the instrument, where a photon-counting detector times their flight. Knowing this time, and the satellite’s position and orientation in space, scientists can calculate Earth’s elevation below.

    ICESat-2 continues key elevation observations begun by the original ICESat satellite (2003 to 2009) and Operation IceBridge (2009 through present), to provide a portrait of change in the beginning of the 21st century. ICESat-2 is slated for launch on a Delta-II rocket in 2017.

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    Global Ice Albedo
    2003.12.12
    This is a conceptual animation showing how polar ice reflects light from the sun. As this ice begins to melt, less sunlight gets reflected into space. It is instead absorbed into the oceans and land, raising the overall temperature, and fueling further melting.
  •
    Bright White Reflects Light
    2004.02.05
    This animation provides a close perspective of the relationship between ice and solar reflectivity. As glaciers, the polar caps, and icebergs (shown here) melt, less sunlight gets reflected into space. Instead, the oceans and land absorb the light, thus raising the overall temperature and adding energy to a vicious circle.

L-30 Science Briefing Graphics

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    ICESat-2 L-30 Science Briefing Graphics
    2018.08.22
    Next month, NASA will launch into space the most advanced laser instrument of its kind, beginning a mission to measure – in unprecedented detail – changes in the heights of Earth’s polar ice.

    NASA’s Ice, Cloud and land Elevation Satellite-2 (ICESat-2) will measure the average annual elevation change of land ice covering Greenland and Antarctica to within the width of a pencil, capturing 60,000 measurements every second.

    “ICESat-2’s new observational technologies will advance our knowledge of how the ice sheets of Greenland and Antarctica contribute to sea level rise while also helping us understand the connection of sea ice loss to the global system,” said Thomas Wagner, cryosphere program scientist in NASA’s Science Mission Directorate.

    ICESat-2 will extend and improve upon NASA's 15-year record of monitoring the change in polar ice heights, which started in 2003 with the first ICESat mission and continued in 2009 with NASA’s Operation IceBridge, an airborne research campaign that monitors the accelerating rate of change.

    ICESat-2 represents a major technological leap in our ability to measure changes in ice height. Its Advanced Topographic Laser Altimeter System (ATLAS) measures height by timing how long it takes individual light photons to travel from the spacecraft to Earth and back.

    NASA will host a media teleconference at 1 p.m. EDT Wednesday, Aug. 22, to discuss the upcoming launch of the Ice, Cloud and land Elevation Satellite (ICESat-2), which will fly NASA's most advanced laser altimeter to measure Earth’s changing ice. The teleconference will stream live on NASA's website.

    ICESat-2 is scheduled to launch Sept. 15 from Vandenberg Air Force Base. The briefing participants are: • Tom Wagner, cryosphere program scientist in the Science Mission Directorate (SMD) at NASA Headquarters • Richard Slonaker, ICESat-2 program executive in SMD • Doug McLennan, ICESat-2 project manager at NASA’s Goddard Space Flight Center • Donya Douglas-Bradshaw, Advanced Topographic Laser Altimeter System (ATLAS) instrument project manager at Goddard • Tom Neumann, ICESat-2 deputy project scientist at Goddard

    For more information: Media Advisory ICESat-2 Video Resources

Facebook Live Broadcasts

  •
    Inside the ATLAS Cleanroom
    External Resource
    Time to suit up! We’re taking you into a clean room at NASA’s Goddard Space Flight Center where the ICESat-2 satellite is currently being monitored. Here engineers and technicians take special precautions to make sure the instrument’s lasers, mirrors, and other components stay perfectly clean. ICESat-2’s sole instrument, called the Advanced Topographic Laser Altimeter System (ATLAS), is being put to the test in this clean room and in a nearby thermal vacuum chamber, before engineers attach it to the rest of the ICESat-2 spacecraft.

High Resolution Still Graphics

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    ICESat-2 Infographic
    2018.09.11
    Downloadable high-resolution infographic illustrating the major technology and science objectives of the Ice, Cloud and land Elevation Satellite-2.
  •
    ICESat-2 Print Material
    2016.04.13
    These illustrations are an outcome of the ICESat-2/SCAD Collaborative Student Project.
  •
    Spacecraft Poster Still
    2014.10.15
    The Ice, Cloud and land Elevation Satellite-2, or ICESat-2, is a laser altimeter that will measure the heights of Earth’s surfaces. With ICESat-2’s high-resolution data, scientists will track changes to Earth’s ice-covered poles, which is witnessing dramatic temperature increases. The mission will also take stock of forests, map ocean surfaces, characterize clouds and more.

    ICESat-2 carries a single instrument called the Advanced Topographic Laser Altimeter System (ATLAS), equipped with a multiple-beam laser, which sends 10,000 pulses of light to the ground each second. A small fraction of the light photons bounce off Earth’s surface and return to the instrument, where a photon-counting detector times their flight. Knowing this time, and the satellite’s position and orientation in space, scientists can calculate Earth’s elevation below.

    ICESat-2 continues key elevation observations begun by the original ICESat satellite (2003 to 2009) and Operation IceBridge (2009 through present), to provide a portrait of change in the beginning of the 21st century. ICESat-2 is slated for launch on a Delta-II rocket in 2017.