Images

The Research Vessel Peterson Underway in San Francisco Bay.

 Winter temperature extremes control the distributions of subtropical fishes. Common snook (Centropomus undecimalis), aggregate at a spring in northern Florida during winter. Snook are warm saltwater game fish, common in Florida, that have been moving further northward as extreme cold spells become less frequent and less intense.

View of the lava lake from the south rim of Halema‘uma‘u, at the summit of Kīlauea, looking north. The western (left) portion of the lava lake remains active, with small scale crustal foundering events. Lava enters the lake at two sources approximately 20 to 30 meters (65 to 100 ft) apart at the base of the western vent spatter cone.

Agassiz Glacier: 8/5/1913 WC Alden, USGS Photographic Library - 8/24/2007, D Fagre, USGS 

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This map of Halema‘uma‘u at the summit of Kīlauea shows 20 m (66 ft) contour lines (dark gray) that mark locations of equal elevation above sea level (asl). The map shows that the lava lake has filled 221 m (725 ft) of the crater, to an elevation of 737 m (2418 ft) asl since the eruption began on December 20, 2020.

Boulder Glacier Ice Cave:  1932, TJ Hileman, GNP Archives – 1988, J DeSanto, U of M Library 

This photo pair inspired the USGS to document glacier and landscape change using oblique photography.

Chaney Glacier:  1911, MR Campbell, USGS Photographic Library – 8/19/2005 Karen Milone, USGS 

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Radioactive isotopes are common in nature and emit particles that can be detected, quantified, and used to characterize environmental processes.

View of the lava lake from the southern rim of Halema‘uma‘u, at the summit of Kīlauea, looking north. The western portion of the lava lake remains active, with small scale crustal foundering events. The white steam from the crater walls is more pronounced due to the heavy rain of the last couple of days.

This map shows the response time people can expect based on Mauna Loa eruptions over the past 200 years.  Different sectors around Mauna Loa are colored according to how quickly lava flows can reach populated areas.  The warmer the color, the more quickly the flows travel.

Repeat photo of Harrison Glacier. 8/20/1913 by WC Alden, USGS Photographic Library, 7/30/2009 by Ralph Thornton, USGS.

Karen Holzer and Lisa McKeon rephotograph Shepard Glacier from the slope of Pyramid Peak, Glacier National Park. 1998 USGS photo.

View looking to the northwest of western fissure area of Halema‘uma‘u lava lake at the Kīlauea summit on March 11, 2021. There is a small incandescent opening at the top of the main (southern) west vent spatter cone (middle-left), and a few smaller incandescent openings at the top of the northern west vent spatter cone (right of the main cone).

Grinnell Glacier in 1910 (Elrod photo, U of M Collection) and 2016 (McKeon photo, USGS).  Retreat resulted in glacier fragmentation, so the 2016 scene shows both Grinnell Glacier, hugging the base of the cliff, and The Salamander Glacier, perched above, along the right edge of the photograph.

Shepard Glacier:  9/6/1913, WC Alden, USGS Photo Library – 8/21/2005, B. Reardon, USGS

Sperry Glacier: circa 1930, MJ Elrod, U of M Library – 9/17/2008, L McKeon, USGS 

Repeating this photo from the same photo point was impossible since the historic photo was shot from the elevated perspective of the glacier’s surface.

Barrier islands off the coast of northern Pinellas County, Florida including Anclote Key, Three Rooker Island, and the northern tip of Honeymoon Island. These barriers protect a highly populated coastline. 

Grinnell and The Salamander Glaciers from the summit of Mt. Gould: 1938, TJ Hileman, GNP Archives – 9/4/2019, L McKeon, USGS

Upper Grinnell Lake has formed as the glacier has retreated.  The change in height of Grinnell Glacier along the cliff face hints at  volume loss during this timespan. 

Jackson Glacier: 1912, MJ Elrod, U of M Library – 9/3/2009, L McKeon, USGS

Trees and vegetation continue to establish themselves at the base of Jackson Glacier as the glacier retreats.

Logan and Red Eagle Glaciers: Aug. 1914, EC Stebinger, USGS Photo Library – 9/2/2009, L McKeon, USGS

These glaciers were once a continuous glacier, but became separate glaciers as retreat progressed.

Swiftcurrent Glacier: circa 1910, M. Elod, GNP Archives - 9/27/2016, L McKeon, USGS

During the timespan between these photos, it is evident that Swiftcurrent Glacier has retreated and wildfire has consumed a patch of trees at the base of Swiftcurrent Mountain, the broad, beige slope in the background.