Previous photo pair1976 - 2005: Minchumina Basin Lowlands near Lake Minchumina Area21/21
thermokarst photo pair
Photo Credits: Fred Dean (1976), Carl Roland (2005)
Ecoregion: Yukon-Kuskokwim Bottomlands
Change Type: Permafrost dynamics
Permafrost dynamicsAnnotation is available
This set of photos is a magnified section of a larger scale photo pair focused on the meadow separating the two lakes. It appears that the islands of woody vegetation visible in the 1976 photo died and contracted by 2005, indicating changes in the hydrologic regime of this wet meadow. These changes are most certainly due to the development of thermokarst topography as underlying permafrost melted and collapsed. The formerly forested mounds have lowered in elevation due to the melting ground beneath and subsided into the wet meadow. The trees thereby drowned and have likely fallen over, making them difficult to spot in the later photograph.