Launched on 12 january 2003, the icesat satellite carried three lasers packaged within the geoscience laser altimetry system glas. 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. Using glasicesat data to derive cflos statistics for the. Concurrent improvements in software for data analysis and visualization have taken advantage of this increased capability. Glas has 3 lasers that emit infrared and visible laser pulses at. Pdf the ice, cloud, and land elevation satellite icesat. Ice, cloud, and land elevation geoscience laser altimeter system. This document will specify the algorithms that process the glas altimeter, lidar and housekeeping level 0 packets and the position and attitude data. I believe that a good program to work with lidar data is lp360 software for arcgis. The icesat science computing facility scf team has developed a software package for visualizing geoscience laser altimeter system glas level 1 and level 2 surface altimetry, atmospheric lidar, and engineering data products. Icesatglas data users are able to subset glas data products by area of interest and time period, as well as enter multiple sets of spatial coordinates. The lidar data provide a vertical profile of the forest structure, from trunk to treetop, allowing the researchers to determine the forest height and the complexity. Bcal lidar tools are opensource tools developed by idaho state university, boise center aerospace laboratory bcal. Glas is a facility instrument designed to measure icesheet topography and associated temporal changes, cloud and atmospheric properties.
The icesat mission is an integral part of the nasa earth. We further explored its ability in deriving forest vertical and horizontal information in cool temperate forests. Appendix b contains tables listing the glas instrument telemetry. Icesat2 data usher in a new age of exploration earthdata. This project is funded by the nasa roses access program to develop a nasa lidar access system nlas to serve laser altimetry data from the nasa spacebased icesat system and the airborne lvis platform through the opentopography system. Evaluation of waveform deconvolution and decomposition. Icesat derived data products cryospheric data glas instrument. Additionally, idlbased visualization software for icesatglas data will be available in the. A program with the primary goal of measuring and understanding the mass balance of the greenland ice sheet.
Characterization of icesatglas waveforms over terrestrial. The glas design combines a 15 cm 6 in precision surface lidar with a sensitive dual wavelength cloud and aerosol lidar. It is a set of tools for visualizing and editing lp360 data obtained by laser scanning lidar. Working with lidar data using other than esri software. Glas is the primary instrument aboard the icesat spacecraft. Thus glas can be used to complete datasets, to produce global maps of canopy height. Measurement of tree height from lidarinsar fusion 158. Icesat data are distributed by the national snow and ice data center nsidc. Ice, cloud, and land elevation satellite icesat data. Mapping of africas mangrove forest extent, height and. Alongtrack timeseries plots show related parameters from multiple.
Yag lasers, which were operated sequentially during the icesat mission. Icesatglas is the first laserranging lidar instrument for continuous global observations of earth put in space. Estimation of aboveground biomass agb at icesatglas footprint level was done by integrating data from multiple sensors using two regression algorithms, viz. 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. Evaluation of vertical accuracy of icesat spaceborne lidar data. Full and subsetted data, data readers, and data visualization tools. Icesat2 ice, cloud, and land elevation satellite 2, part of nasas earth observing system, is a satellite mission for measuring ice sheet elevation and sea ice thickness. While the volume of data from operation icebridge is about 30 terabytes tb per year, icesat2 is producing just under 1 tb of data per day. Combining satellite lidar, airborne lidar, and ground. The glas instrument aboard icesat provided fullwaveform lidar data for the earths forests from 2003 to 2010. 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. Glas produces 16 data products including levels 1a, 1b, and 2 laser altimetry and atmospheric lidar data.
Pod in the news glas education key facts science objectives instrument description. The geoscience laser altimeter system glas on board the ice, cloud, and land elevation satellite icesat was the first orbiting space lidar to monitor earths polar regions for climate studies. In order to study the forest classification effect of large footprint lidar date we used svmsupport vector machine method to analyze the icesatglas ice, cloud and land elevation satellite geoscience laser altimeter system date in wangqing bureau, jilin province. Rapid geographic and temporal subsetting is performed with the glas scf data management system. Glasicesat l2 global land surface altimetry data gla 14 2003. The geoscience laser altimeter system glas on the board ice, cloud, and land elevation satellite icesat, is the first longduration space borne fullwaveform lidar for measuring the topography. Using glasicesat data to derive cflos statistics for the design of future spacebased active optical. These tools can be used for processing, analyzing and visualizing lidar data. Icesat glas science processing software document series icesat contacts. Evaluation of vertical accuracy of icesat spaceborne lidar data v34 over dehradun district. Icesatglas lidar data has been analysed by a combined approach of modelling the lidar signal with a monte. A structural classification of australian vegetation using. Satellite lidar data from icesat, high altitude airborne lidar data from lvis. Glas combines a precision surface lidar with a sensitive dual wavelength cloud and aerosol lidar.
In analysis we first used idl to convert the icesatglas original binary data into ascii format. Icesat glas science processing software document series. According to our results from the first study, the calculated average cbd values, across all 50 plots, were 0. The documents are organized according to nasa earth science data. Grass gis supports basic and advanced lidar data processing and analysis. The geoscience laser altimeter system glas is a nextgeneration space lidar. The combination of icesatglas and srtm has been fruitful. Schutz, glas science team leader university of texas center for space research austin, texas 787595321 david w. Several early approaches to extrapolation have been developed using airborne lidar data.
This project is funded by the nasa roses access program to develop a nasa. You can try the software company laserdata lis for saga. Vertical forest structure from icesatglas lidar data. Launched on january 12, 2003, icesat completed its mission in october 2009, and was deorbited in august 2010. To visualize glas data, a software package, named the interactive data.
The goal of the project is to provide integrated access to existing nasa lidar data products, as well as ondemand processing capability, and enhanced qaqc. 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. Simulated icesat2 data were generated from dr lidar or fw lidar data using the simulator provided by the icesat2s nasa science definition team sdt. In total, 118 datasets including 3 mabel datasets and 115 simulate icesat2 datasets with multiple ecosystem. This study reports on the first attempt to use cloud boundary and optical depth retrievals from the glas lidar to assess the accuracy of cloudtop heights obtained with modis onboard nasaterra and aqua and seviri onboard meteosat8. Glas receiver design the glas lidar utilized three nearly identical qswitched nd. Since 2004, new als commercial systems called fullwaveform lidar have. Pirotti icesatglas waveform signal processing for ground cover classification 14 clouds baltsavias, 1999. Icesat glas data points used in the assessment over an image of the dem. Launched on 12 january 2003, after seven years in orbit and 18 laseroperations campaigns, the icesats science mission ended due to the failure of.
Study on forest type classification based on icesatglas. On this regard, remote sensing, and in particular light detection and ranging lidar data, could be the perfect tool. They are written in idl programming language and is intended to be used as addon in the envi remote sensing software package. Hancock iii, science software development leader nasagsfc wallops flight facility wallops island, virginia 23337 h.
Establish standard web service layers for icesatglas at the nsicd and lvis data obtained from gsfc that will provide a standardized data access interface to these data. Icesatglas laser altimetry data have become increasingly utilized for vegetation mapping and canopy characterization. The laser altimeter measures the time required for a laser pulse of 5 nanosecond duration to complete the round trip from the instrument to the earths surface and back to the instrument. The glas lasers were designed to transmit 6ns wide pulses at a rate of 40 hz.
Science data systems for satellite and airborne lidar data. Height and biomass of mangroves in africa from icesat glas. Icesatglas canopy height sensitivity inferred from. However, large footprint, full waveform satellite lidar data, such as data provided by the geoscience laser altimeter system glas aboard the ice cloud and land elevation satellite icesat, proved to have the potential for assessing vegetation parameters at unprecedented scales, from regional to. I also recommend the application server providing you lidar point clouds. Glas lidarderived global estimates of forest canopy.
Optimizing spaceborne lidar and very high resolution. Automated dem validation using icesat glas data mary pagnutti robert e. Glas is a spacebased full waveform lidar and sole instrument onboard icesat. It is the sole science payload for nasa s icesat mission. 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.
The geoscience laser altimeter system glas is the sole instrument developed to fly on the ice, cloud, and land elevation satellite icesat. While there were several data documentation errors initially encountered, the. For example, 3,4,6 related groundbased or airborne lidarderived estimates of biomass or volume to intersecting icesatglas metrics thereby allowing these measures to be. The only global insar and lidar data sets currently available are from the spaceborne srtm shuttle radar topography mission and icesatglas ice, cloud, and land elevation satellite geoscience laser altimeter system. Glas the geoscience laser altimeter system is the first laserranging lidar instrument for continuous global observations of earth, which will make unique atmospheric observations as an important component of the ese climate change.
The data pool offers direct online access to all the lp daac eos products at no cost to the user. Asofmarch2014,othostsover615billionlidarreturnsand167,794km2ofdata. Glas was the first spaceborne lidar instrument developed for continuous global observations of the earth. Glas is carried on the ice, cloud and land elevation satellite icesat, which launched january 2003 00. Icesats primary objectives are to determine the mass balance of the polar ice sheets and their contributions to global sea level change, and to obtain essential data for prediction of future changes in ice volume and sealevel. Geolas is a lidar data viewer and converter capable to read and convert lidar las format. In addition to software modifications, any laser ranging system requires. Icesatglas waveform signal processing for ground cover. For updates on glas and the icesat spacecraft, please visit the icesat homepage glas was sucessfully launched aboard the icesat, from vandenberg air force base, california on sunday, january 12, 2003, at 7. Free and open source software for geospatial foss4g india 2015, at dehradun, india. Data products from the ice, cloud, and land elevation. Waveform shapes are dependent upon complex relationships between several facto. Canopy height estimates from the icesatglas instrument.
The content on this site will be static for the forseeable future. This page lists names and links to publicly accessible documents related to the icesatglas mission. Icesatglas mission preservation documents national snow. The present study aims at combining information from spaceborne lidar icesatglas and high resolution optical data to estimate forest biomass.
The data are often provided as sets of very dense x, y, z points or in a more complex, public file binary format called las that may include multiple returns as well as intensities. 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. The geoscience laser altimeter system glas homepage. The objective of this study was to use lidar metrics to predict competition on the basis of distancedependent competition indices of individual trees. Icesatglas canopy height sensitivity inferred from airborne lidar craig mahoney, chris hopkinson, alex held, natascha kljun, and eva van gorsel.