• NSIDC DAAC is currently upgrading our data ingest process for NASA Earthdata Cloud. During this transition, users may notice temporary interruptions in data availability or notice small data gaps. All gaps will be resolved as quickly as possible. During this upgrade jpeg browse imagery will also not be available for preview in Earthdata search. Please reach out to NSIDC User Services with any questions or concerns.

  • As of 01 September 2025, the NASA AMSR2 SIPS will stop processing and delivering updates to Advanced Microwave Scanning Radiometer Unified (AMSR Unified) data sets. For more information, see "User notice: Updates to NASA AMSR-E/AMSR2 Unified data sets to cease on 01 September 2025".

  • On Wednesday, September 10 from 9:00 a.m. to 2:30 p.m. (US Mountain Time), this data set may not be available in the legacy data archive due to a planned system maintenance. Earthdata Cloud access will remain available for data sets that have migrated. Users of the SMAP near real-time products should use the NASA LANCE HTTPS File System for data access.

  • The NSIDC DAAC is retiring access to its legacy, on-premises data archive and transitioning to the NASA Earthdata Cloud as the primary data archive. View planned retirement dates here.

AMSR-E/AMSR2 Unified L3 Daily 12.5 km Brightness Temperatures, Sea Ice Concentration, Motion & Snow Depth Polar Grids, Version 1
Data set id:
AU_SI12
DOI: 10.5067/RA1MIJOYPK3P
This is the most recent version of these data.
Version Summary
Initial release
In this section
  • Rendering Links ...
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Overview

This data set reports average daily horizontally and vertically polarized brightness temperatures; sea ice concentrations; and snow depths over sea ice on 12.5 km resolution north and south polar stereographic grids. Ungridded sea ice motion data are also available for the Arctic. The data are derived from observations acquired by the Advanced Microwave Scanning Radiometer (AMSR) for EOS (AMSR-E) and AMSR2 instruments that have been spatially resampled by the Japan Aerospace Exploration Agency (JAXA) to unify the AMSR-E and AMSR2 missions. Brightness temperatures are available at 18.7 GHz, 23.8 GHz, 36.5 GHz and 89.0 GHz for ascending and descending orbits, and as a single daily average. Sea ice concentrations are generated with the Enhanced NASA Team (NT2) algorithm; a separate variable reports the daily sea ice concentration difference between the legacy AMSR Basic Bootstrap Algorithm (ABA) and the NT2.
Parameter(s):
BRIGHTNESS TEMPERATURE
SEA ICE CONCENTRATION
SEA ICE MOTION
SNOW DEPTH
Platform(s):
Aqua
GCOM-W1
Sensor(s):
AMSR-E
AMSR2
Data Format(s):
HDF-EOS5
ASCII
Temporal Coverage:
  • 1 June 2002 to 4 October 2011
  • 2 July 2012 to present
Temporal Resolution:
  • 1 day
Spatial Resolution:
  • 12.5 km
  • 12.5 km
Spatial Reference System(s):
  • NSIDC Sea Ice Polar Stereographic North
    EPSG:3411
  • NSIDC Sea Ice Polar Stereographic South
    EPSG:3412
Spatial Coverage:
  • N:
    -39.23
    S:
    -89.24
    E:
    180
    W:
    -180
  • N:
    89.24
    S:
    30.98
    E:
    180
    W:
    -180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

Data Access & Tools

A free NASA Earthdata Login account is required to access these data. Learn More

HTTPS File System

Get Data
Quickly download a few files using a web browser, or access data through a command-line utility such as WGET.
Related Help Resources
NASA Earthdata Cloud Data Access Guide
Type:
service

Data Access Tool

Search & Discover
Get Data
Filter files before downloading based on date, spatial area, or file name. Choose from various download options, such as Python script. Export bounding boxes as a GeoJSON.
Related Help Resources
How to filter and order from a data set web page
How to use Earthdata Download
Type: Web Application
Last updated:
View Metadata

NASA Earthdata Search

Visualize
Search & Discover
Get Data
Search and order data from all NASA DAACs using spatial and temporal filters in a map interface. Reformatting, reprojecting, and subsetting options are available for some data sets.
Related Help Resources
How to search, order, and customize data with NASA Earthdata Search
Type: Web Application

earthaccess

Get Data
Search & Discover
earthaccess is a python library to search and access NASA Earth science data with just a few lines of code.
Supported software languages:
Python
Related Help Resources
GitHub Repository
Type: Downloadable Software
Last updated:
View Metadata

Bulk Programmatic Data Access Service

Get Data
Programmatically request selected data products through NSIDC's API. Bulk download using spatial and temporal filters, or incorporate data access commands into code/scripts as needed.
Related Help Resources
Programmatic Data Access Guide
Type:
service
Last updated:
View Metadata

NASA Worldview

Visualize
Search & Discover
Get Data
Customize
GIS
Browse and display global satellite imagery layers from NASA GIBS. Download raw data, share screenshots, and create animations from the imagery.
Related Help Resources
How to visualize and download data with NASA Worldview
Type: Web Application
Customization Capabilities:
data reformatting
Output Formats:
GEOTIFF
GIF
JPEG
KML
PNG
 

NASA Earthdata Cloud (AWS S3)

Get Data
Access data directly from the NASA Earthdata Cloud via Amazon Web Services Simple Storage Service (AWS S3). This access option is only available when working within the us-west-2 region and requires additional AWS S3 credentials.
Related Help Resources
NASA Earthdata Cloud Data Access Guide
AWS S3 Credentials
Type:
service
View Metadata

HDFView

Visualize
Explore contents of HDF4 and HDF5 files, including file structure, metadata, and parameter values.
Related Help Resources
HDFView 3.X User's Guide
Type: Downloadable Software
Output Formats:
ASCII
HDF4
HDF5

NASA LaRC Satellite Overpass Predictor

Visualize
Calculate past and future satellite overpasses, based on latitude/longitude or map location.
Type: Web Application

Panoply Data Viewer

Visualize
Analyze
Visualize georeferenced arrays in NetCDF, HDF and GRIB formats. Plot data on global or regional maps, choosing from multiple map projections. Overlay continent outlines or masks.
Type: Downloadable Software
Output Formats:
ASCII
CSV
GIF
HDF-EOS2
HDF-EOS5
HDF4
HDF5
JPEG
KML
NETCDF-3
NETCDF-4
PNG
TIFF

Documentation

Help Articles

General Questions & FAQs

FAQs About NSIDC DAAC's Earthdata Cloud Migration
This article covers frequently asked questions about the NASA NSIDC DAAC's Earthdata cloud migration project and what it means to data users.
Read More
When will the legacy, on-premises archive be retired?
The NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is migrating its primary data access from its legacy, on-premises archive to the NASA Earthdata Cloud.
Read More

How to Articles

Filter and order from a data set web page using the Data Access Tool
Many NSIDC DAAC data sets can be accessed using 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:
Read More
How do I convert an HDF5/HDF-EOS5 file into binary format?
To convert HDF5 files into binary format you will need to use the h5dump utility, which is part of the HDF5 distribution available from the HDF Group. How you install HDF5 depends on your operating system.
Read More
NASA Earthdata Cloud Data Access Guide
The NASA Earthdata Cloud is the NASA cloud-based archive of Earth observations. It is hosted by Amazon Web Services (AWS). Learn how to find and access NSIDC DAAC data directly in the cloud.
Read More
Programmatic Data Access Guide
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.
Read More