DOI: 10.3886/e233443
title: Climate.gov Data Snapshots: Arctic Sea Ice Age

description: <b>Q: How has the age of Arctic Sea Ice changed over time?
</b><b>
 </b><br><b>A:</b> Since
 the late 1900s, Arctic sea ice has thinned, and less sea ice has 
persisted in the Arctic over multiple melt seasons. The trend toward 
younger, thinner sea ice over time reflects warming temperatures in the 
Arctic. As older ice is thicker than younger ice, the reduced area of 
old ice also indicates a reduction in the total volume of ice.

 
 <br><b>Q: Where do these measurements come from?
 
</b><b>
 </b><br><b>A: </b>Scientists
 estimate the age of sea ice by combining satellite observations of ice 
locations and extent with buoy data on winds and motion.

 
 <br><b>Q: What do the colors mean?</b><b>
 </b><br><b>A: </b>Colors
 show the age of sea ice floating in the Arctic Ocean. The darkest blue 
areas on the map show seasonal or first-year ice, which formed during 
the most recent winter. White areas show where ice is more than four 
years old. Ice thickness is strongly correlated with ice age. First year
 ice ranges from 4 to 12 inches (10 to 30 centimeters) thick, while 
multiyear ice ranges from 6 to 12 feet (2 to 4 meters) thick. This 
correlation means that in general, the brighter the color, the thicker 
ice.

 
 <br><b>Q: Why do these data matter?</b><b>
 </b><br><b>A:</b> In
 the mid-to-late 1900s, a core of thick, old year-round sea ice covered 
much of the Arctic Ocean. Around that core, seasonal ice formed each 
winter and melted each summer. North of Alaska, a looping current called
 the Beaufort Gyre historically acted as a nursery for young sea ice 
where ice could persist and thicken. Ice growth in the gyre roughly 
offset the steady transport of ice out of the Arctic Ocean through the 
Fram Strait east of Greenland. Since the year 2000, warmer summers have 
caused ice to melt in the southern stretch of the Beaufort Gyre, so less
 multiyear ice has persisted. The result is younger, thinner sea ice 
than in decades past. Today, the amount of thick, old ice in the Arctic 
is a small fraction of what it was in the 1980s. Because young, thin ice
 melts more easily than old, thick ice, the trend toward thinner ice is 
self-reinforcing.

 
 <br><b>Q: How did you produce these snapshots?</b><b>
 </b><br><b>A:</b> Data
 Snapshots are derivatives of existing data products: to meet the needs 
of a broad audience, we present the source data in a simplified visual 
style.

 
 
 <br><b>Additional information</b>
 These Arctic Sea Ice Age maps use NSIDC Quicklook Arctic Weekly EASE-Grid Sea Ice Age, Version 1 data from 2020 to now, while maps from 2019 and earlier use NSIDC EASE-Grid Sea Ice Age, Version 4 data. Both datasets are available as PNGs (.png) and NetCDF (.nc) files. 

 
 <br><b>References</b>
 
 Perovich, D., Meier, W., Tschudi, M., Farrell, 
S., Hendricks, S., Gerland, S., Kaleschke, L., Ricker, R., Tian-Kunze, 
X., Webster, M., Woods, K. (2019). Sea ice. 2019 Arctic Report Card.
 <br>Source: https://www.climate.gov/maps-data/data-snapshots/data-source/arctic-sea-ice-age
 




<br><br>This upload includes two additional files:<br>* Arctic Sea Ice Age _NOAA Climate.gov.pdf is a screenshot of the main Climate.gov site for these snapshots (https://www.climate.gov/maps-data/data-snapshots/data-source/arctic-sea-ice-age
 




)<br>* Cimate_gov_ Data Snapshots.pdf is a screenshot of the data download page for the full-resolution files. <br><br><br><br>
description: Data is divided in to folders by image resolution -- full size (zip), broadcast (png), small (png), and large (png). Occasionally there may be one image missing in a particular size but available in another size. Weekly images are missing for all file sizes for some dates in Dec. 2023 and Aug. 2024.<br><br>Data downloaded from climate.gov 6/15/2025 - 6/18/2025 (large and full size) and 6/22/2025 (small and broadcast).