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Analysis of altimetric data acquired by the GLAS instrument requires accurate determination of the laser spot location on the Earth's surface (ice, land, water, clouds) or geolocation of the laser spot. The spot location with respect to the Earth's center of mass (geocenter) is determined by both the orbital location of GLAS in an appropriate reference frame and the direction of the laser beam described in the same reference frame.

Data products from VIIRS are created to be similar to MODIS data products to ensure the continuity needed for the development of snow and sea ice climate records beyond the life expectancy of MODIS. The temporal resolution and spatial extent are identical in MODIS and VIIRS. A benefit of VIIRS snow and sea ice products, however, is the higher spatial resolution when compared to similar MODIS products (375m vs. 500m for snow and 375m/750m vs. 1000m for sea ice, respectively).

For ICESat/GLAS mission data, the elevation of the surface at each laser footprint is the height of the spacecraft minus the measured distance to the surface. A standard parameterization is used to calculate surface elevation for ice sheets, oceans, and sea ice, using the elevation of the maximum peak and no more than two Gaussian functions with a minimum spacing of 30 ns (4.5 m) between Gaussian centers. For land elevations, the centroid of the return signal is used; a maximum of six Gaussians is allowed with 5 ns (75 cm) minimum spacing.

NOAA@NSIDC data recently transitioned to HTTPS. The directory structure has NOT changed, but the beginning of the URL has changed from:ftp://sidads.colorado.edu/pub/DATASETS/to:https://noaadata.apps.nsidc.org/NOAA/

Currently three NOAA@NSIDC data sets are available in NOAA's PolarWatch Data Catalog. Please note that in the catalog the Climate Data Record (CDR) data sets are split up into Antarctic and Arctic data sets:

This tutorial covers four different methods for accessing data through FTP:

There are external Jupyter notebooks available that can be used to search for GrIMP products and incorporate them into a new QGIS project:

This article illustrates the how to convert NetCDF variables to single-band GeoTIFFs. You will need to have the Geospatial Data Abstraction Library (GDAL, http://gdal.org/) installed on your system before continuing.Once you have acquired the NetCDF file of the tile(s) you are interested in and have GDAL installed, you may execute the following command: gdal_translate NETCDF:"Input_FileName.nc":variable_name Output_FileName.tif

This article describes how to convert the u (horizontal) and v (vertical) components from the ice motion data set to East and North components on the Earth's surface. Instructions for both the Northern and Southern Hemispheres are described below: Northern Hemisphere The latitudes and longitudes for the Northern Hemisphere are shown in Figure 1. 

Data subscriptions provide automatic notifications and updates when new data becomes available. This guide covers two methods for setting up subscriptions: the Earthdata Search web interface and the command-line PO.DAAC Data Subscriber tool. PrerequisitesCreate an Earthdata login account if you don't already have one: https://urs.earthdata.nasa.gov/Earthdata SearchEarthdata Search offers two subscription types: dataset subscriptions and granule subscriptions.

The Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data are distributed in gridded binary format. NSIDC provides IDL routines to ingest and read the data.

This external R tutorial guides you through an R script for the NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration data in PolarWatch: https://github.com/CoastWatch-WestCoast/r_code/blob/master/accessing_projected_datasets.md It covers the following topics:

This step-by-step tutorial demonstrates how to access MODIS and SMAP data using the Application for Extracting and Exploring Analysis Ready Samples (AppEEARS). AppEEARS allows users to access, explore, and download point and area data with spatial, temporal, and parameter subsets. Interactive visualizations with summary statistics of the sample results allow the user to preview and interact with their sample before downloading the data. NSIDC DAAC data sets available in AppEEARS include:

If you need to use data from Daily 4km Gridded SWE and Snow Depth from Assimilated In-Situ and Modeled Data over the Conterminous US, Version 1 in a GIS (e.g. ArcMap, QGIS), we suggest converting the NetCDFs to GeoTIFFs first. We recommend using the Geospatial Data Abstraction Library (GDAL) to do this, and instructions for downloading and installing GDAL can be found here: https://gdal.org/download.html

This article explains how to find LVIS science products in NASA's Earthdata Search using filenames from the exploratory tools and KMZ files available on the NASA LVIS campaigns webpage.

The following are instructions on how to import and geolocate SMAP Level-1C HDF5 data in ENVI. Testing notes Software: ENVI Software version: 5.3 and above. If using version 5.3, service pack 5.3.1 is needed.  Platform: Windows 7 Data set: SMAP L1C Radiometer Half-Orbit 36 km EASE-Grid Brightness Temperatures (SPL1CTB) Data set version: 2 Date tested: 12/14/15

The following are instructions on how to import and geolocate SMAP Level-3 Radiometer Soil Moisture HDF5 data in ENVI. Testing notes Software: ENVI Software version: 5.3 Platform: Windows 7 Data set: SMAP L3 Radiometer Global Daily 36 km EASE-Grid Soil Moisture (SPL3SMP) Data set version: 2 Date tested: 12/17/15

This article describes the actions to perform in order to work with NSIDC-0611 in ArcGIS. At the time of writing, this tutorial is relevant for ArcMap10.5 and earlier. The following steps will show you how to prepare the binary files for import, format conversion, and geolocation/projection.

This short article explains where to find Global Monthly EASE-Grid SWE data products and then how to import them into ArcGIS. The global, monthly SWE EASE-Grid products can be found here: Global Monthly EASE-Grid Snow Water Equivalent Climatology, Version 1 (NSIDC-0271)

This article describes the process for importing IMS ASCII data, in 1, 4, and 24km resolutions into ArcGIS using ArcMap v10.5. The data product is called IMS Daily Northern Hemisphere Snow and Ice Analysis at 1 km, 4 km, and 24 km Resolutions (G02156). Note that there are both packed and unpacked versions of the 24km resolution data.