• On Wednesday, February 21, from 9:00 a.m. to 1:30 p.m. (US Mountain Time), the following data collections may not be available due to planned system maintenance: ASO, AMSR Unified, AMSR-E, Aquarius, High Mountain Asia, IceBridge, ICESat/GLAS, ICESat-2, LVIS, MEaSUREs, MODIS, Nimbus, SMAP, SnowEx, SSM/I-SSMIS and VIIRS.

  • For a list of known issues with this product, see the Known Issues document under the Documentation section of the page.

ATLAS/ICESat-2 L3B Daily and Monthly Gridded Polar Sea Surface Height Anomaly, Version 3
Data set id:
ATL21
DOI: 10.5067/ATLAS/ATL21.003
This is the most recent version of these data.
Version Summary
-Correct reported longitude values to agree with NSIDC Polar Stereographic projections
-Added grid_mapping attribute to land_mask_map array
-Updated the MSS variable description. Added mentions of the source of the MSS (which uses CryoSat-2 data) and clarified the use of the tide-free system

Overview

ATL21 contains daily and monthly gridded polar sea surface height (SSH) anomalies, derived from the along-track ATLAS/ICESat-2 L3A Sea Ice Height product (ATL10, V6). The ATL10 product identifies leads in sea ice and establishes a reference sea surface used to estimate SSH in 10 km along-track segments. ATL21 aggregates the ATL10 along-track SSH estimates and computes daily and monthly gridded SSH anomaly in NSIDC Polar Stereographic Northern and Southern Hemisphere 25 km grids.
Parameter(s):
SEA SURFACE HEIGHT ANOMALY _SSHA_
Platform(s):
ICESat-2
Sensor(s):
ATLAS
Data Format(s):
HDF5
Temporal Coverage:
14 October 2018 to present
Temporal Resolution:
  • 1 day
Spatial Resolution:
  • 25 km
  • 25 km
Spatial Reference System(s):
NSIDC Sea Ice Polar Stereographic North
EPSG:3411

NSIDC Sea Ice Polar Stereographic South
EPSG:3412
Spatial Coverage:
N:
90
S:
-90
E:
180
W:
-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

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Help Articles

General Questions & FAQs

This article covers frequently asked questions about the NASA NSIDC DAAC's Earthdata cloud migration project and what it means to data users.
This short article describes the customization services available for ICESat-2 data using Earthdata Search.

How to Articles

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.