MEaSUREs Greenland Ice Velocity: Selected Glacier Site Velocity Maps from InSAR, Version 4
Data set id:
NSIDC-0481
DOI: 10.5067/GQZQY2M5507Z
This is the most recent version of these data.
Version Summary
Version Summary
This version contains the following changes:
-Updated temporal coverage
-Use of GDAL 3.2.1 to create cloud optimized GeoTIFFs
-Data reprocessed utilizing a corrected DEM. See user note in section 2.2.5
-Updated temporal coverage
-Use of GDAL 3.2.1 to create cloud optimized GeoTIFFs
-Data reprocessed utilizing a corrected DEM. See user note in section 2.2.5
Overview
This data set, part of the NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, provides velocity estimates determined from Interferometric Synthetic Aperture Radar (InSAR) data for major glacier outlet areas in Greenland, some of which have shown profound velocity changes over the MEaSUREs observation period. The InSAR Selected Glacier Site Velocity Maps are produced from image pairs measured by the German Aerospace Center's (DLR) twin satellites TerraSAR-X / TanDEM-X (TSX / TDX). The measurements in this data set are provided in addition to the ice sheet-wide data from the related data set, MEaSUREs Greenland Ice Sheet Velocity Map from InSAR Data.
See Greenland Ice Mapping Project (GrIMP) for more related data.
Parameter(s):
ICE VELOCITY
Platform(s):
TDX, TSX
Sensor(s):
TDX-1, X-SAR
Data Format(s):
GeoTIFF, JPEG
Temporal Coverage:
12 June 2008 to 20 September 2023
Temporal Resolution:
- 11 day
Spatial Resolution:
- 100 m
- 100 m
Spatial Reference System(s):
WGS 84 / NSIDC Sea Ice Polar Stereographic North
EPSG:3413
Spatial Coverage:
N:
82
S:
60
E:
-20
W:
-70
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.
Strengths and Limitations
Strengths
- Can be used to examine a velocity time series for an individual glacier (or an area or point within the glacier), particularly for inversions where shear margins are important.
- Has much better spatial resolution than similar full Greenland products (e.g., MEaSUREs Greenland Ice Sheet velocity mosaics).
- Includes more frequent coverage in the summer, when seasonal variations due to melt and calving are likely to occur.
- One of the highest spatial resolution GrIMP data sets for individual glaciers.
- Provides a consistent time series for many glaciers that extends back to 2009 (see Fig. 3 in Joughin et al, 2018).
Limitations
- Only covers the downstream regions of a limited number of glaciers.
- Although posted at 100 m, the actual resolution is approximately 460 m.
Data Access & Tools
A free NASA Earthdata Login account is required to access these data. Learn More
Sample Data Image
Image
Documentation
Help Articles
How to Articles
Many NSIDC DAAC data sets can be accessed using the NSIDC DAAC's Data Access Tool. This tool provides the ability to search and filter data with spatial and temporal constraints using a map-based interface.Users have the option to
Harmony API Quickstart Guide: Customizing NASA NSIDC DAAC data in Earthdata Cloud
Below the image in this article, you will find sample code in IDL, MATLAB, and Python to read in a GeoTIFF file, extract the metadata, and create an image.
The code has been tested with the following data products:
We recommend using the Geospatial Data Abstraction Library (GDAL) to convert GeoTIFF files into a different format.
We recommend using the Geospatial Data Abstraction Library (GDAL) or a GIS to reproject geoTIFF files.
There are external Jupyter notebooks available that can be used to search for GrIMP products and incorporate them into a new QGIS project:
There are external Jupyter notebooks available that can be used to download user-defined spatial subsets of the following MEaSUREs GrIMP products:
All data from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is directly accessible through our HTTPS file system using Wget or curl. This article provides basic command line instructions for accessing data using this method.