Alarming Findings: Glaciers in the Western United States Are Disappearing

Melting Ice Climate Change

A recent study by Portland State University has uncovered the alarming disappearance and transformation of glaciers in the Western United States. The inventory, updating a mid-20th-century record, found that many glaciers have vanished or no longer qualify as glaciers. This loss poses serious environmental challenges, including affecting water flow and contributing to sea level rise.

Glaciers in the Western United States are disappearing. 

A recent study by researchers at Portland State University has revealed significant changes in glaciers. The findings include the complete disappearance of certain glaciers, the cessation of movement in others, and a reduction in size for some below the minimum threshold of 0.01 square kilometers. Additionally, the study identified certain formations as rock glaciers, which are essentially rocky debris containing ice within their pores.

Detailed Inventory by PSU Researchers

Andrew Fountain, a geology professor emeritus at PSU, and research assistant Bryce Glenn, inventoried glaciers and perennial snowfields in the western continental U.S. using aerial and satellite imagery between 2013 and 2020. The inventory, published in the journal Earth System Science Data, identified 1,331 glaciers and 1,176 perennial snowfields. 

It updates a mid-20th century inventory, derived from U.S. Geological Survey topographic maps made over a 40-year span, and provides a baseline for estimating future changes amid a warming climate.

“Glaciers are disappearing and this is a quantification of how many around us have disappeared and will probably continue to disappear,” Fountain said.

Excluded Glaciers and Environmental Impact

The new inventory excludes 52 of the 612 officially named glaciers because they are no longer glaciers. The official names are those listed in the federal Geographic Names Information System — the nation’s repository for the names and locations of landscape features. Milk Lake Glacier in Washington’s Mt. Baker-Snoqualmie National Forest and Wyoming’s Hooker Glacier have disappeared altogether; 25 were instead classified as perennial snowfields, which unlike glaciers don’t move; 18 had areas smaller than the commonly used threshold of 0.01 square kilometers or roughly the size of two football fields side-by-side; and seven were considered rock glaciers.

The loss of glaciers impacts more than aesthetics. Glaciers act as a natural regulator of streamflow, Fountain said. They melt a lot during hot dry periods and don’t melt much during cool rainy periods. As glaciers shrink, they have less ability to buffer seasonal runoff variations and watersheds become more susceptible to drought. Retreating glaciers also leave behind sharp, steep embankments on either side, which can collapse and result in catastrophic debris flows. Globally, the loss of glaciers is also a major contributor to sea level rise.

Fountain’s co-authors are Bryce Glenn, a PSU alum and research analyst, and Christopher McNeil, a geophysicist with the USGS’ Alaska Science Center. Looking ahead, the group is studying the volume change of the glaciers to see how much ice they’ve lost since the USGS mapping.

Missing Glaciers: List of officially named glaciers not classified as glaciers and excluded from the final inventory

StateRegionGlacier NameReason
CaliforniaSierra NevadaMatthes Glaciersrock glacier
CaliforniaSierra NevadaMount Warlow Glacierrock glacier
CaliforniaSierra NevadaPowell Glacierrock glacier
ColoradoFront RangeIsabelle Glacierperennial snowfield
ColoradoFront RangeMills Glacierperennial snowfield
ColoradoFront RangeMoomaw Glacierperennial snowfield
ColoradoFront RangePeck Glacierperennial snowfield
ColoradoFront RangeRowe Glacier< 0.01km2
ColoradoFront RangeSaint Marys Glacier< 0.01km2
ColoradoFront RangeTaylor Glacierrock glacier
ColoradoFront RangeThe Dove< 0.01km2
IdahoLost River RangeBorah Glacierrock glacier
MontanaBeartooth Mountains–Absaroka RangeGrasshopper Glacierrock glacier
MontanaCabinet MountainsBlackwell Glacierperennial snowfield
MontanaCrazy MountainsGrasshopper Glacierrock glacier
MontanaLewis RangeBoulder Glacierperennial snowfield
MontanaMission–Swan–Flathead rangesFissure Glacier< 0.01km2
MontanaMission–Swan–Flathead rangesGray Wolf Glacierperennial snowfield
OregonCascade RangeCarver Glacierperennial snowfield
OregonCascade RangeClark Glacierperennial snowfield
OregonCascade RangeIrving Glacierperennial snowfield
OregonCascade RangeLathrop Glacier< 0.01km2
OregonCascade RangePalmer Glacierperennial snowfield
OregonCascade RangeSkinner Glacierperennial snowfield
OregonCascade RangeThayer Glacier< 0.01km2
OregonWallowa MountainsBenson Glacierperennial snowfield
WashingtonCascade Range–NorthernLyall Glacierperennial snowfield
WashingtonCascade Range–NorthernMilk Lake Glacierdisappeared
WashingtonCascade Range–NorthernSnow Creek Glacierperennial snowfield
WashingtonCascade Range–NorthernSpider Glacierperennial snowfield
WashingtonCascade Range–NorthernTable Mountain Glacier< 0.01km2
WashingtonCascade Range–SouthernApe Glacier< 0.01km2
WashingtonCascade Range–SouthernDryer Glacierperennial snowfield
WashingtonCascade Range–SouthernForsyth Glacier< 0.01km2
WashingtonCascade Range–SouthernMeade Glacierperennial snowfield
WashingtonCascade Range–SouthernNelson Glacier< 0.01km2
WashingtonCascade Range–SouthernPackwood Glacierperennial snowfield
WashingtonCascade Range–SouthernPinnacle Glacier< 0.01km2
WashingtonCascade Range–SouthernPyramid Glaciers< 0.01km2
WashingtonCascade Range–SouthernShoestring Glacier< 0.01km2
WashingtonCascade Range–SouthernStevens Glacierperennial snowfield
WashingtonCascade Range–SouthernTalus Glacierperennial snowfield
WashingtonCascade Range–SouthernUnicorn Glacier< 0.01km2
WashingtonCascade Range–SouthernWilliwakas Glacierperennial snowfield
WashingtonOlympic MountainsAnderson Glacierperennial snowfield
WashingtonOlympic MountainsLillian Glacier< 0.01km2
WyomingAbsaroka RangeDuNoir Glacier< 0.01km2
WyomingTeton RangePetersen Glacier< 0.01km2
WyomingTeton RangeTeepe Glacierperennial snowfield
WyomingWind River RangeHooker Glacierdisappeared
WyomingWind River RangeHarrower Glacierperennial snowfield
WyomingWind River RangeTiny Glacier< 0.01km2

Reference: “Inventory of glaciers and perennial snowfields of the conterminous USA” by Andrew G. Fountain, Bryce Glenn and Christopher Mcneil, 15 September 2023, Earth System Science Data.
DOI: 10.5194/essd-15-4077-2023

2 Comments on "Alarming Findings: Glaciers in the Western United States Are Disappearing"

  1. Reading about Greenland and its Accelerated Melting: Greenland’s Glacier Retreat Doubled in 20 Years ( it shouldn’t come as a surprise to the people that monitor the Glaciers in the USA and with El Nino this winter we shouldn’t be surprised at more receding of Glacier

  2. Western US glaciers have been retreating for 20,000 years, except for a slight re-bound during the Little Ice Age.

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