The icesat mission was designed to provide elevation data needed to determine ice. Nasa icesat captures earth in spectacular 3d images. Icesat elevations and slope grids icesat elevations and slope grids glasicesat antarctic and greenland dems and derived grids. Glas is a facility instrument designed to measure icesheet topography and associated temporal changes, as well as cloud and atmospheric properties. In addition, algorithms had to be developed to process icesat2 data. Icesat was designed to operate for three to five years. This document is applicable to the glas standard data software consisting of the icesat science investigatorled processing system isips software and the glas instrument support terminal ist software. Canopy height estimation in french guiana with lidar. Icesat ice, cloud and land elevation satellite icesat is a nasagsfc mission within the ese earth science enterprise program. Antarctic 1 km digital elevation model dem from combined ers1 radar and icesat laser satellite altimetry. Icesatglas data have already played a vital role in waterlevel change studies, especially for those lakes with steep lakeshore, which may not be so obvious in change of areas li et al. Geolocation of the footprints was evaluated using an alsderived dem. Icesat will collect data about the earth using the lasers on the glas instrument. Full and subsetted data, data readers, and data visualization tools.
Retrieving leaf area index using icesatglas fullwaveform. Glas lidarderived global estimates of forest canopy. It will also provide topography and vegetation data around the globe, in addition to the polarspecific coverage over the greenland and antarctic ice sheets. Glasicesat 1 km laser altimetry digital elevation model of greenland. I have to import icesat glas14 product data into arcgis. The name is a contraction based on the words light and radar. Characterization of canopy fuels using icesatglas data. By timing how long it takes laser beams to travel from the satellite to earth and back, scientists can calculate the height of glaciers, sea ice, forests, lakes and more including the changing ice. Laser 1 started to collect data in february 2003, but it failed shortly after its launch. The geoscience laser altimeter system glas on icesat has a 1064 nm laser channel for surface altimetry and dense cloud heights and a 532 nm lidar channel for the vertical distribution of clouds. During the initial on orbit test operation, a pump diode module on the. Glas produces 16 data products including levels 1a, 1b, and 2 laser altimetry and atmospheric lidar data.
The combination of icesatglas and srtm has been fruitful. This is an animation showing data from icesats geoscience laser altimeter system glas. Geospatial data exploration, analysis, and visualization a subset of relevant core concepts and modern geospatial data science approaches for icesat data analysis instructor. Open altimetry is now operational for icesat data, and the entire icesat data set glasicesat l1b global elevation data, version 34 is available for discovery and download. The principal objective of the icesat mission, and its geoscience laser altimeter system glas instrument, is to measure the surface elevations of the large ice sheets covering antarctica and greenland and determine how they are changing.
Icesat is scheduled to be launched on january 11th, 2002 aboard a boeing delta ii rocket. Each data granule has an associated browse product. The following tables provide links to software for reading and viewing nasa icesatglas data. The ice, cloud and land elevation satellite icesat laser altimetry mission from 2003 to 2008 provided an important dataset for elevation measurements. Data from seasat, geosat, gfo, ers1, ers2, envisat and cryosat2 salellites have.
Thus glas can be used to complete datasets, to produce global maps of canopy height. In addition, operation of glas over land and water will provide alongtrack topography. The table below summarizes the mission standard data products, which are available through the national snow and ice data center. Schutz, glas science team leader university of texas center for space research austin, texas 787595321 david w. The grids available here were generated from the first two years of data 2003 feb to 2005 may. The bus provided the glas instrument with power, data services, thermal control, spacecraft pointing control, orbit maintenance propulsion, and spacetoground communications. Over 50 different global datasets are represented with daily, weekly, and monthly snapshots in a variety of formats. Nsidc daac distributes 15 level1 and level2 data products from the geoscience laser altimeter system glas instrument that was aboard the nasa ice, cloud, and land elevation icesat satellite. May 2, 2019 icesat ice, cloud, and land elevation satellite is the benchmark earth observing system mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics. The glas lasers emit infrared and visible laser pulses at 1064 and 532 nm wavelengths. Advanced discovery, processing, and visualization services.
Using glasicesat data to derive cflos statistics for the design of future spacebased active optical. Cloud data can be seen over about 15 orbits on october 6, 2003. Nsidc daac distributes 15 level1 and level2 data products from the geoscience laser altimeter system glas instrument that was. Testing indicated that each glas laser should last for two years, requiring glas to carry three lasers in order to fulfil the nominal mission length. The geoscience laser altimeter system glas instrument on the ice, cloud, and land elevation satellite. Icesat data are distributed by the national snow and ice data center nsidc. Glasicesat l1a global altimetry data hdf5 v033 level1a altimetry data glah01 include the transmitted and received waveform from the altimeter. Pod in the news glas education key facts science objectives instrument description.
This study explores icesatglas waveform data in thuringian forest, a low mountain range located in central germany. The prime objective is to monitor the mass balance of the polar ice sheets and their contributions to global sea level change. Tools for reading glas data and converting it to text are available at icesat national. Level2 altimetry data provide surface elevations for ice sheets glah12, sea ice glah, land glah14, and oceans glah15. Icesat 2 short for ice, cloud and land elevation satellite, slated to launch in 2018, will use lasers and a very precise detection instrument to measure the elevation of earths surface. Using python to extract icesat glas elevation data. Parameterization of surface roughness based on icesatglas.
Icesat ice, cloud,and land elevation satellite is the benchmark earth observing system mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics. This version of the animation starts with the full globe, moves south to antarctica, over the pole, then north to africa. The icesat mission will provide multiyear elevation data needed to determine ice sheet mass balance as well as cloud property information, especially for stratospheric clouds common over polar areas. Glas atmospheric sciences home page wallops flight facility glas web site icesat home history operations icesat primary data products icesat. Icesat was a satellite mission for measuring ice sheet mass balance, cloud and aerosol.
We kindly request that you cite the following citations in any publications. For altimetry data on sea ice, ocean, or ice sheets, other data droducts are available. Glas icesat l1a global altimetry data hdf5 v033 level1a altimetry data glah01 include the transmitted and received waveform from the altimeter. The first channel is designed for the measurement of surface topography. Height and biomass of mangroves in africa from icesatglas. The newest addition to nasa s fleet of earth observing satellites has only one scientific instrument called glas. The geoscience laser altimeter system glas is an integral part of the nasa earth science enterprise ese. The following tables list the glas data sets and related products.
Fuel properties were estimated from data derived from the waveform themselves. Glasicesat 500 m laser altimetry digital elevation model of antarctica. Waterlevel changes in chinas large lakes determined from. Land cover classification using icesatglas full waveform data. The glas includes a laser system to measure distance, a global positioning system gps receiver, and a startracker attitude determination system. Using glasicesat data to derive cflos statistics for the. Icesat derived inland water surface spot heights iwsh. Icesat2 is the 2ndgeneration mission scheduled for launch in late 2015. Due to its restricted operations plan, creative use of.
Please read this special note first before you proceed further you can find examples quickly using the search box below. In this study, an algorithm for estimating lai from the icesat ice, cloud and land elevation satelliteglas geoscience laser altimeter system data was proposed and applied to a forest area in the tibetan plateau. Hancock iii, science software development leader nasagsfc wallops flight facility wallops island, virginia 23337 h. Icesat2 short for ice, cloud and land elevation satellite, slated to launch in 2018, will use lasers and a very precise detection instrument to measure the elevation of earths surface. Full and subsetted data, data readers, and data visualization tools may be downloaded from nsidc. Icesat ice, cloud, and land elevation satellite is the benchmark earth observing system mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics. This dataset iwsh was derived from glasicesat gla14 global land surface altimetry data zwally et al, 2012. Citeseerx the relevance of glasicesat elevation data. Pdf icesatglas waveform signal processing for ground cover. In this paper, we report some preliminary assessment of the glas data for building. Glasicesat l2 ocean altimetry data hdf5 v034 glah06 is used in conjunction with glah05 to create the level2 altimetry products. Icesat2 data usher in a new age of exploration earthdata. For this data set, mean forest canopy height was derived for a global glas waveform data set n12,336,553 using an algorithm described by lefsky et al.
The present work was carried out as part of isros earth observation and application mission eoam project. I managed to export into an ascii file the binary glas data using ngat tool, but the coordinates system are in an uncommon format topexposeidon. Glasicesat l1b global elevation data national snow and ice. While the glas instrument aboard the first icesat spacecraft looked at the intensity of a returned laser signal and detected groups of returning photons at one time, icesat. Evaluation of vertical accuracy of icesat spaceborne lidar data. Ice, cloud, and land elevation geoscience laser altimeter system. Other tools and programming languages examples can be found here. In this study, based on icesatglas data, an automatic method to determining the trend of waterlevel changes had been proposed. Glas estimates were validated using als data previously validated with field data. The icesat2 laser altimetry mission article pdf available in proceedings of the ieee 985. Use the links to visit each data sets landing page, where you can view documentation and options for obtaining the data. Citeseerx document details isaac councill, lee giles, pradeep teregowda. The lowlevel data products are developed through the icesat2 project science office. Launched on 12 january 2003, after seven years in orbit and 18 laseroperations campaigns, the icesat s science mission ended due to the failure of.
Glas standard data software development team under the direction of the glas science team leader. Although the geoscience laser altimeter system glas onboard the nasa ice, cloud and land elevation satellite was not designed for urban applications, its 3d measurement capability over the globe makes it a nice feature for consideration in monitoring urban heights. The quality of glasicesat geoscience laser altimeter system data was investigated for lake leman in switzerland and france by comparing laser data to. Since mangrove forests grow around sea level, srtm provide a first estimate of forest height interferometric phase center which can be calibrated with field and glas data. This allows icesat waveform energy data files and icesat2 photon data files to be stored in their original hdf5 format. The geoscience laser altimeter system glas onboard nasas ice, cloud, and land elevation satellite icesat mission is the first spaceborne lidar system.
Highlights canopy fuel properties were estimated using icesatglas satellite lidar data. Apparently they provide an idl script to convert the coordinates, but i cant get it work. Icesat glas science processing software document series. Glas builds its facts one point at a time the technology behind glas is called lidar. The glas instrument aboard icesat provided fullwaveform lidar data for the earths forests from 2003 to 2010. Access to glas binary data was removed 01 august, 2017. Retrieving leaf area index using icesatglas fullwaveform data. The data are initially laid out in the order that is was collected followed by continued movement around the scene. Glas produces 16 data products including levels 1a, 1b, and 2 laser. The glah14 is the glasicesat l2 global land surface altimetry data hdf5. Lidar is a distance measuring system similar to radar, except that instead of radio waves it uses pulses of laser light for range finding. Citeseerx article icesatglas data as a measurement tool.
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