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A variety of features can be detected in the RAMP image mosaic. SAR data allow ready discrimination between areas of high snow accumulation, crevassed regions, and areas susceptible to seasonal melt. Field camps and features such as runways and heavily traveled snowmobile tracks are also visible. The collection of images below demonstrates the degree of detail provided by the RAMP image mosaic. Please note the white and/or blue colors used in the annotations on the images are simply for better contrast against the background and have no other significance.

NSIDC has scripts that run several times a day. If new SNODAS files are found, these scripts will automatically post them to our FTP server. If you need data sooner than the normal timeframe that NSIDC uploads files to our FTP site, you can contact NOHRSC, as they distribute the data for operational users.

AMSR-E Slow Rotation Data is a research product distributed by the Japan Aerospace Exploration Agency (JAXA) that have been obtained with a slow rotation of AMSR-E's antenna at 2 rotations per minute (rpm).

Hierarchical Data Format (HDF) is the standard data format for all NASA Earth Observing System (EOS) data products.It is also known as HDF-EOS.

There are 40 laser shots in one second which are associated with the transmit pulses from the ICESat/GLAS instrument. The first shot is from the laser, the last shot is the 40th record of that transmitted pulse. The GLAS Altimetry Product Usage Guidance  document explains it like this: "Thirty-nine delta times are provided, which the user adds to the full UTC time of the first transmit time in each record, to calculate the 40 laser shot times." Last Updated April 2020

The Normalized Difference Snow Index (NDSI) snow cover is an index that is related to the presence of snow in a pixel and is a more accurate description of snow detection as compared to Fractional Snow Cover (FSC). Snow typically has very high visible (VIS) reflectance and very low reflectance in the shortwave infrared (SWIR), a characteristic used to detect snow by distinguishing between snow and most cloud types. Snow cover is detected using the NDSI ratio of the difference in VIS and SWIR reflectance; NDSI = ((band 4-band 6) / (band 4 + band 6)).

The Network Common Data Form (NetCDF) file format was developed by the Unidata project at the University Corporation for Atmospheric Research (UCAR). NetCDF (network Common Data Form) is a set of interfaces for array-oriented data access and a freely distributed collection of data access libraries for C, Fortran, C++, Java, and other languages. The netCDF libraries support a machine-independent format for representing scientific data.

Surface roughness greatly affects the elevation measurement accuracy. Over most of the ice sheets, the accuracy of each elevation measurement is 15 cm. Average ice elevation changes less than 1 cm will be detected by averaging the elevation differences observed at many points in selected regions of the ice sheets. Over land, the vertical accuracy of the elevation measurements will be better than a meter in regions of low slope and up to 10 m in regions of large slopes.

The standard waveform fit is optimized for "ice sheet-like" returns. The majority of these are single-peaked, narrow waveforms. The standard fit allows for only two peaks. Alternate waveform fitting is meant to capture up to six peaks. More peaks are necessary for more complex waveforms over land, vegetated surfaces and crevassed parts of ice sheets and glaciers. Another key difference between standard and alternate fit concerns the noise floor threshold.

Each frequency is looking at a different size footprint. Each frequency has its own feedhorn, and is thus susceptible to independent pointing errors. The most important benefit of resampling (or smoothing) is to create a suite of frequencies that are all looking at the same scene. So, when the higher-resolution channels are resampled to match the footprints of the lower-resolution channels, the data are smoothed. In the not-resampled (unsmoothed) channels (denoted by 'o' in Table 5 of the User Guide):

The MODIS Swath-to-Grid Toolbox (MS2GT) is a set of software tools that can be used to read HDF-EOS files containing MODIS swath data and produce flat binary files containing gridded data in a variety of map projections. Multiple input files corresponding to successively acquired 5 minute MODIS "scenes" can be processed together to produce a seamless output grid.

HMA DEMs cover portions of eleven countries. The products are created from DigitalGlobe Inc. satellite imagery and have a relatively small footprint, especially compared to NASA missions

This article describes the Arctic and Antarctic projections used for gridded Operation IceBridge data sets. Arctic The standard projection parameters for Northern Hemisphere Operation IceBridge data are: Polar Stereographic Standard Parallel 70° N Longitude of the origin (central meridian): 45° W WGS 84 ellipsoid This projection is defined as EPSG:3413. Examples of other NSIDC DAAC data sets using this projection include:

This short article describes the customization services available for ICESat-2 data using Earthdata Search.

A list of featured external softwares and their compatibility with EASE-Grid and EASE-Grid 2.0 are listed in the article below. For a complete list of EASE-Grid and EASE-Grid 2.0 tools curated by NSIDC, please read the article

This is most likely due to a problem with Windows Winzip which corrupts the file upon downloading (you will see that the file size will have changed from the original located on ftp) You can correct this by changing some settings in WinZip:

On 25 October 2003, at 8:49 a.m. (JST), JAXA discovered that ADEOS-II had been switched to light load mode due to an unknown anomaly. (Light load is a mode in which all observation equipment is automatically turned off to minimize power consumption). No further earth observation data were received after that time.

Several parameters help quantify the shape of the GLAS laser footprint, which change slightly for each campaign. These parameters are:

During the first IceBridge campaign for this data set (2009 Antarctica), the camera was flown in a demonstration mode. Input from the science community requested that panchromatic data be collected - so as to maximize grey-level possibility. The panchromatic data are 1-band data. Most all of the 2009 imagery for Antarctica was acquired in that mode. During the other campaigns, the cameras were configured to collect data in color, which is 3-band. There is a metadata field provided in each GeoTIFF which identifies the mode (pan or color) associated with the data.

The Aqua satellite travels along the dashed line marking the center of a scan. When that center point reaches its maximum latitude, the ascending half orbit (green dots) ends, and a new descending half orbit (orange) starts. All orbits will be split at this same latitude, all the ascending orbits will reach the same maximum latitude, and all the descending orbits will reach a different (and higher) maximum latitude. This creates pole holes with different radii. The South Pole is similar, except that ascending and descending are swapped.