[NASA] Fans of the Arctic

[SpaceMan 0]

Earth Observatory

1. This is the hidden content, please

   • Sign In
   • or
   • Sign Up
2. This is the hidden content, please

   • Sign In
   • or
   • Sign Up
3. Fans of the Arctic

• This is the hidden content, please

  • Sign In
  • or
  • Sign Up
• This is the hidden content, please

  • Sign In
  • or
  • Sign Up
• This is the hidden content, please

  • Sign In
  • or
  • Sign Up
• This is the hidden content, please

  • Sign In
  • or
  • Sign Up
• Topics
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
• More Content
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
• About
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
  • This is the hidden content, please

    • Sign In
    • or
    • Sign Up
• This is the hidden content, please

  • Sign In
  • or
  • Sign Up

 

This is the hidden content, please

• Sign In
• or
• Sign Up

Alluvial fans form along a braided river channel on Severny Island in the Russian Arctic in an image acquired on August 1, 2025, by the

This is the hidden content, please

• Sign In
• or
• Sign Up

 (Operational Land Imager) on

This is the hidden content, please

• Sign In
• or
• Sign Up

.

NASA Earth Observatory/Lauren Dauphin

Editor’s Note: Today’s story is the answer to the 

This is the hidden content, please

• Sign In
• or
• Sign Up

.

Call it an alluvial face-off. On the southern end of Severny Island in the Russian Arctic, rivers rush down from rugged terrain flanking a broad valley. Upon reaching flatter ground, the waters slow and distribute sediment into cone-shaped features called

This is the hidden content, please

• Sign In
• or
• Sign Up

. Several appear in opposing orientations alongside a braided river in this

This is the hidden content, please

• Sign In
• or
• Sign Up

image.

Severny Island (Ostrov Severnyy) is a mountainous,

This is the hidden content, please

• Sign In
• or
• Sign Up

landmass in the frigid high latitudes of the Northern Hemisphere. Part of the

This is the hidden content, please

• Sign In
• or
• Sign Up

archipelago, the island is largely covered in glacial ice. Some glaciers, especially in the north, terminate in the sea, while others end on land, feeding meltwater into glacial streams.

Sediment-laden streams, along with the island’s topography, create favorable conditions for the formation of alluvial fans. The features typically appear at the base of steep mountain ranges, where narrow river channels open onto flatter terrain. There, rivers can slow, divide into smaller channels, and

This is the hidden content, please

• Sign In
• or
• Sign Up

. Over time, the channels migrate back and forth to build up fan-shaped deposits. Dueling fans line several northwest-southeast-trending valleys in the wider view below.

This is the hidden content, please

• Sign In
• or
• Sign Up

A wide view of southern Severny Island in the Russian Arctic shows ice-capped mountains interrupted by broad valleys lined with alluvial fans. The image was acquired on August 1, 2025, by the

This is the hidden content, please

• Sign In
• or
• Sign Up

 (Operational Land Imager) on

This is the hidden content, please

• Sign In
• or
• Sign Up

.

NASA Earth Observatory/Lauren Dauphin

Seasonal snowmelt and

This is the hidden content, please

• Sign In
• or
• Sign Up

likely keep Severny’s rivers supplied with ample fan-building material.

This is the hidden content, please

• Sign In
• or
• Sign Up

that higher river flows during the warmer months, driven by snowmelt, can carry more sediment out of the mountains. Glaciers also produce large volumes of eroded material as they grind downslope, some of which flushes out in meltwater.

Smaller, land-terminating mountain glaciers, like those on southern Severny Island, are particularly prone to melting as the

This is the hidden content, please

• Sign In
• or
• Sign Up

. Severny’s ice is relatively understudied due to its remoteness, but satellite observations give scientists an understanding of its health. Recent analyses incorporating

This is the hidden content, please

• Sign In
• or
• Sign Up

found that land-terminating glaciers across the Novaya Zemlya archipelago thinned during the

This is the hidden content, please

• Sign In
• or
• Sign Up

and

This is the hidden content, please

• Sign In
• or
• Sign Up

, especially at lower elevations.

NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the 

This is the hidden content, please

• Sign In
• or
• Sign Up

. Story by Lindsey Doermann.

Downloads

This is the hidden content, please

• Sign In
• or
• Sign Up

August 1, 2025

JPEG (19.56 MB)

References & Resources

• Małecki, J. (2022)
  This is the hidden content, please

  • Sign In
  • or
  • Sign Up
  . The Cryosphere, 16, 2067–2082.
• Melkonian, A.K., et al. (2016)
  This is the hidden content, please

  • Sign In
  • or
  • Sign Up
  . Remote Sensing of Environment, 174, 244-257.
• NASA Earth Observatory (2009, July 30)
  This is the hidden content, please

  • Sign In
  • or
  • Sign Up
  . Accessed July 13, 2026.
• National Geographic Society (2023, October 19)
  This is the hidden content, please

  • Sign In
  • or
  • Sign Up
  . Accessed July 13, 2026.
• Science Education Resource Center, Carleton College (2026, June 9)
  This is the hidden content, please

  • Sign In
  • or
  • Sign Up
  . Accessed July 13, 2026.

You may also be interested in:

Stay up-to-date with the latest content from NASA as we explore the universe and discover more about our home planet.

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

3 min read

During the 2022 summer melt season, sediment plumes and fractured sea ice traced swirling eddies in a branch of the…

Article

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

3 min read

Icy, isolated Peter I Island stirred up a show in the atmosphere off the West Antarctic coast.

Article

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

3 min read

Drifting sea ice fragments near Alaska’s Saint Lawrence and Nunivak islands and colorful water around the Yukon Delta heralded the…

Article

1

2

3

4
Next

Keep Exploring

Discover More from NASA Earth Science

Subscribe to Earth Observatory Newsletters

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

Earth Observatory Image of the Day

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

Explore Earth Science

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

Earth Science Data

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up