MABEL photon-counting laser altimetry data in Alaska for ICESat-2 simulations and development

Abstract. Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) is scheduled to launch in 2017 and will carry the Advanced Topographic Laser Altimeter System (ATLAS), which is a photon-counting laser altimeter and represents a new approach to satellite determination of surface elevation. Given the new technology of ATLAS, an airborne instrument, the Multiple Altimeter Beam Experimental Lidar (MABEL), was deployed in July 2014 to Alaska to provide data needed for satellite-algorithm development, simulating key elements of the photon-counting sampling strategy, and assessing elements of the resulting data that may vary seasonally. Here, we compare MABEL lidar data to in situ observations in Southeast Alaska to assess instrument performance in summer conditions and in the presence of glacier surface melt ponds and a wet snowpack. Results indicate that: 1) the ATLAS 90 m beam-spacing strategy will provide a robust assessment of across-track slope that is consistent with shallow slopes (<1°) of an ice-sheet interior over 50 to 150 m length scales; 2) the dense along-track sampling strategy of photon counting systems provides crevasse detail; and 3) MABEL 532 nm wavelength light may be sampling the surface and subsurface of shallow (approximately 2 m deep) supraglacial melt ponds.

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MABEL photon-counting laser altimetry data in Alaska for ICESat-2 simulations and development

The Cryosphere ◽

10.5194/tc-10-1707-2016 ◽

2016 ◽

Vol 10 (4) ◽

pp. 1707-1719 ◽

Cited By ~ 14

Author(s):

Kelly M. Brunt ◽

Thomas A. Neumann ◽

Jason M. Amundson ◽

Jeffrey L. Kavanaugh ◽

Mahsa S. Moussavi ◽

...

Keyword(s):

New Technology ◽

Photon Counting ◽

Sampling Strategy ◽

Laser Altimeter ◽

Glacier Surface ◽

Algorithm Development ◽

In Situ Data ◽

Melt Ponds ◽

Water Saturated

Abstract. Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) is scheduled to launch in late 2017 and will carry the Advanced Topographic Laser Altimeter System (ATLAS), which is a photon-counting laser altimeter and represents a new approach to satellite determination of surface elevation. Given the new technology of ATLAS, an airborne instrument, the Multiple Altimeter Beam Experimental Lidar (MABEL), was developed to provide data needed for satellite-algorithm development and ICESat-2 error analysis. MABEL was deployed out of Fairbanks, Alaska, in July 2014 to provide a test dataset for algorithm development in summer conditions with water-saturated snow and ice surfaces. Here we compare MABEL lidar data to in situ observations in Southeast Alaska to assess instrument performance in summer conditions and in the presence of glacier surface melt ponds and a wet snowpack. Results indicate the following: (1) based on MABEL and in situ data comparisons, the ATLAS 90 m beam-spacing strategy will provide a valid assessment of across-track slope that is consistent with shallow slopes (< 1°) of an ice-sheet interior over 50 to 150 m length scales; (2) the dense along-track sampling strategy of photon counting systems can provide crevasse detail; and (3) MABEL 532 nm wavelength light may sample both the surface and subsurface of shallow (approximately 2 m deep) supraglacial melt ponds. The data associated with crevasses and melt ponds indicate the potential ICESat-2 will have for the study of mountain and other small glaciers.

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Evaluation of ICESat-2 ATL03 and ATL13 River Levels in Mountainous Areas of China

10.5194/egusphere-egu21-13378 ◽

2021 ◽

Author(s):

Heidi Ranndal ◽

Karina Nielsen ◽

Ole B. Andersen

Keyword(s):

Photon Counting ◽

Water Levels ◽

Synthetic Aperture ◽

Mountainous Areas ◽

Laser Altimeter ◽

Inland Water ◽

Ice Cloud ◽

The World ◽

Rivers And Lakes ◽

Along Track

The data from NASA&#8217;s Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) mission offer a unique opportunity to map rivers and lakes with an unprecedented number of observations in areas where previous missions have failed to provide valuable water level estimates. ICESat-2 carries just one instrument, the Advanced Topographic Laser Altimeter System (ATLAS), which is a green wavelength, photon-counting lidar, and several data products are available, such as the ATL03 product, which holds the photon data, and the ATL13 product which contains estimated inland water surface heights and statistics for water bodies across the world.&#160;The along-track resolution of the ATL03 product is less than 1 m, and with the three pairs of beams, i.e. six beams in total, the mission provides exceptional opportunities for inland water studies in areas with mountainous topography.In general, inland water altimetry in mountainous areas has proven to be a challenge for both conventional Low Resolution Mode (LRM) and Synthetic Aperture Radar (SAR) altimetry, causing issues not only with waveforms, but also the position of the range window. In this study, we present the ability of ICESat-2 to obtain water levels in several mountainous rivers in China, where even SAR missions such as CryoSat-2 and Sentinel-3 have been unsuccessful. Results are shown for both the ATL03 and the ATL13 version 4 products to evaluate their performances.

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Alignment determination of the Hayabusa2 laser altimeter (LIDAR)

Earth Planets and Space ◽

10.1186/s40623-020-01342-8 ◽

2021 ◽

Vol 73 (1) ◽

Author(s):

Hirotomo Noda ◽

Hiroki Senshu ◽

Koji Matsumoto ◽

Noriyuki Namiki ◽

Takahide Mizuno ◽

...

Keyword(s):

Altimeter Data ◽

Gravity Assist ◽

Laser Altimeter ◽

Trajectory Error ◽

Flight Data ◽

Camera Image ◽

Operation Period ◽

The Cross ◽

Along Track

AbstractIn this study, we determined the alignment of the laser altimeter aboard Hayabusa2 with respect to the spacecraft using in-flight data. Since the laser altimeter data were used to estimate the trajectory of the Hayabusa2 spacecraft, the pointing direction of the altimeter needed to be accurately determined. The boresight direction of the receiving telescope was estimated by comparing elevations of the laser altimeter data and camera images, and was confirmed by identifying prominent terrains of other datasets. The estimated boresight direction obtained by the laser link experiment in the winter of 2015, during the Earth’s gravity assist operation period, differed from the direction estimated in this study, which fell on another part of the candidate direction; this was not selected in a previous study. Assuming that the uncertainty of alignment determination of the laser altimeter boresight was 4.6 pixels in the camera image, the trajectory error of the spacecraft in the cross- and/or along-track directions was determined to be 0.4, 2.1, or 8.6 m for altitudes of 1, 5, or 20 km, respectively.

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A Method of Extracting High-Accuracy Elevation Control Points from ICESat-2 Altimetry Data

Photogrammetric Engineering & Remote Sensing ◽

10.14358/pers.21-00009r2 ◽

2021 ◽

Vol 87 (11) ◽

pp. 821-830

Author(s):

Binbin Li ◽

Huan Xie ◽

Shijie Liu ◽

Xiaohua Tong ◽

Hong Tang ◽

...

Keyword(s):

Large Scale ◽

Comprehensive Evaluation ◽

Photon Counting ◽

High Accuracy ◽

Airborne Lidar ◽

Altimeter Data ◽

Control Points ◽

Laser Altimeter ◽

Terrain Elevation ◽

Along Track

Due to its high ranging accuracy, spaceborne laser altimetry technology can improve the accuracy of satellite stereo mapping without ground control points. In the past, full-waveform ICE, CLOUD, and Land Elevation Satellite (ICESat) laser altimeter data have been used as one of the main data sources for global elevation control. As a second-generation satellite, ICESat-2 is equipped with an altimeter using photon counting mode. This can further improve the application capability for stereo mapping because of the six laser beams with high along-track repetition frequency, which can provide more detailed ground contour descriptions. Previous studies have addressed how to extract high-accuracy elevation control points from ICESat data. However, these methods cannot be directly applied to ICESat-2 data because of the different modes of the laser altimeters. Therefore, in this paper, we propose a method using comprehensive evaluation labels that can extract high-accuracy elevation control points that meet the different level elevation accuracy requirements for large scale mapping from the ICESat-2 land-vegetation along-track product. The method was verified using two airborne lidar data sets. In flat, hilly, and mountainous areas, by using our method to extract the terrain elevation, the root-mean-square error of elevation control points decrease from 1.249–2.094 m, 2.237–3.225 m, and 2.791–4.822 m to 0.262–0.429 m, 0.484–0.596 m, and 0.611–1.003 m, respectively. The results show that the extraction elevations meet the required accuracy for large scale mapping.

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The Ice, Cloud, and Land Elevation Satellite – 2 (ICESat-2): Mission Status, Science Results, and Outlook

10.5194/egusphere-egu2020-22119 ◽

2020 ◽

Author(s):

Nathan Kurtz ◽

Thomas Neumann ◽

Lori Magruder

Keyword(s):

Sea Ice ◽

Ice Sheets ◽

Great Promise ◽

Polar Regions ◽

Laser Altimeter ◽

Ice Cloud ◽

Ability To Act ◽

Loss Of Mass ◽

The Many ◽

Along Track

The Ice, Cloud, and Land Elevation Satellite-2 has entered it&#8217;s second year on orbit, and continues to collect high-quality measurements of the changing cryosphere. The Advanced Topographic Laser Altimeter System (ATLAS) has now emitted more than 500 billion laser shots which provide elevation measurements of sea ice and the polar oceans, glaciers and ice sheets, the world&#8217;s forests, oceans, lakes and rivers in addition to vertical profiles of clouds and aerosols. ATLAS is an innovated lidar technology that utilizes low power and higher repetition rates to collect measurements every 70 cm along-track. These measurements have been shown to have high precision and accuracy comparable to or better than past and present cryospheric missions. The ICESat-2 data has also shown great promise with its ability to act as both complementary observations to many other missions as well as allow for us to extend the timeseries associated with our understanding of elevation and mass change in the polar regions. In this presentation, we will provide an update on the operations and health of the observatory, review the many available data products served through the National Snow and Ice Data Center in the US, and highlight the early science results from the mission. As of this writing, more than 2.5 million data granules have been downloaded by 1500 unique data users. Initial science papers have documented the ongoing loss of mass from the Antarctic and Greenland ice sheets, the ability of ICESat-2 to measure the seasonal changes in sea ice freeboard and thickness throughout the year, and the potential for world-wide measurements of coastal bathymetry.&#160;

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Iterative Pointing Angle Calibration Method for the Spaceborne Photon-Counting Laser Altimeter Based on Small-Range Terrain Matching

Remote Sensing ◽

10.3390/rs11182158 ◽

2019 ◽

Vol 11 (18) ◽

pp. 2158

Author(s):

Nan ◽

Feng ◽

Liu ◽

Keyword(s):

Photon Counting ◽

Calibration Method ◽

High Repetition Rate ◽

Search Method ◽

Airborne Lidar ◽

Altimeter Data ◽

Small Range ◽

Laser Altimeter ◽

Ice Cloud ◽

Terrain Matching

The satellite, Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) has been equipped with a new type of spaceborne laser altimeter, which has the benefits of having small footprints and a high repetition rate, and it can produce dense footprints on the ground. Focusing on the pointing angle calibration of this new spaceborne laser altimeter, this paper proposes a fast pointing angle calibration method using only a small range of terrain surveyed by airborne lidar. Based on the matching criterion of least elevation difference, an iterative pointing angle calibration method was proposed. In the experiment, the simulated photon-counting laser altimeter data and the Ice, Cloud and Land Elevation Satellite-2 data were used to verify the algorithm. The results show that when 1 km and 2.5 km lengths of track were used, the pointing angle error after calibration could be reduced to about 0.3 arc-seconds and less than 0.1 arc-seconds, respectively. Meanwhile, compared with the traditional pyramid search method, the proposed iterative pointing angle calibration method does not require well-designed parameters, which are important in the pyramid search method to balance calculation time and calibration result, and the iterative pointing angle calibration method could significantly reduce the calibration time to only about one-fifth of that of the pyramid search method.

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REVIEW OF NOISE FILTERING ALGORITHM FOR PHOTON DATA

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w10-105-2020 ◽

2020 ◽

Vol XLII-3/W10 ◽

pp. 105-110

Author(s):

J. P. Huang ◽

Y. Q. Xing ◽

L. Qin

Keyword(s):

Forest Structure ◽

Structural Parameters ◽

Photon Counting ◽

Accurate Estimation ◽

Noise Filtering ◽

Laser Altimeter ◽

Cloud Data ◽

Filtering Algorithm ◽

Ice Cloud ◽

Scientific Results

Abstract. As a continuation of Ice, Cloud, and Land Elevation Satellite-1 (ICESat-1)/Geoscience Laser Altimeter System (GLAS), the Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) , which is equipped with the Advanced Topographic Laser Altimeter (ATLAS) system, was successfully launched in 2018. Since ICESat-1/GLAS has facilitated scientific results in the field of forest structure parameter estimation, how to use the ICESat-2/ATLAS photon cloud data to estimate forest structure parameters has become a hotspot in the field of spaceborne photon data application. However, due to the weak photon characteristics of the ICESat-2/ATLAS system, the system is extremely susceptible to noise, which poses a challenge for its subsequent accurate estimation of forest structural parameters. Aiming to filter out the noise photons, the paper introduces the advantages of the spaceborne lidar system ICESat-2/ATLAS than ICESat-1/GLAS. The paper summarizes the research of the simulated photon-counting lidar (PCL) noise filtering algorithm and noise filtering on spaceborne.

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