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Learn
What is the Cryosphere?
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Frozen Ground & Permafrost
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Cryosphere Glossary
mud circle
mud circle
a type of nonsorted circle developed in fine-grained materials.
Topic(s):
frozen ground or permafrost
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Arctic Sea Ice News & Analysis (ASINA)
Ice Sheets Today
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Data
Explore Data
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Submit Data
Submit NASA Data to NSIDC DAAC
Submit Data to Other NSIDC Programs
User Resources
Get Started with Data
Data Announcements
Help Center
Data Tools
Documents
Levels of service
NASA Earthdata Forum
Data Programs
About our Programs
NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC)
NOAA at NSIDC
Exchange for Observations and Local Knowledge of the Arctic (ELOKA)
Data Policies
Our Research
Learn
What is the Cryosphere?
Parts of the Cryosphere
Arctic Weather & Climate
Frozen Ground & Permafrost
Glaciers
Ice Sheets
Ice Shelves
Sea Ice
Snow
Ask a Scientist
Cryosphere glossary
About
About NSIDC
What we do
Our People
Published Research
Our History
Diversity, Equity & Inclusion
Careers
For the Media
Contact Us
Citation Policies
Web Policy
Land Acknowledgement