Thank you to NASA for these Images of Change

Arctic Sea-Ice Coverage Hits Record Low
1984 – 2012


The area of the Arctic Ocean covered in ice increases during the winter and then shrinks during the summer, usually reaching the year’s low point in September. The minimum coverage for 2012 set a record low since at least 1979. These images compare the 1984 minimum, which was roughly equal to the average minimum extent for 1979–2000, with that of 2012, when the minimum was about half that. The 2013 minimum was larger, but continued the long-term downward trend of about 12 percent sea-ice loss per decade since the late 1970s, a decline that accelerated after 2007. The 2016 minimum was tied for the second-lowest on record. “At the rate we’re observing this decline,” said NASA scientist Joey Comiso, “it’s very likely that the Arctic’s summer sea ice will completely disappear within this century.”

Muir Glacier Melt, Alaska
August 13, 1941 – August 31, 2004


The 1941 photograph shows the lower reaches of Muir Glacier and its tributary, Riggs Glacier. The two glaciers filled Muir Inlet. In the 2004 photograph, Muir Glacier, continuing a retreat nearly two centuries long, is located about 4 miles (7 kilometers) to the northwest, out of the field of view. Riggs Glacier has retreated some 0.4 miles (0.6 kilometers). Both glaciers have thinned substantially.

U.S. Geological Survey, Department of the Interior. Earlier image by W. O. Field, courtesy of the National Snow and Ice Data Center and Glacier Bay National Park and Preserve Archive. Later image is a USGS photograph by Bruce F. Molina.

McCarty Glacier Melt, Alaska
July 30, 1909 – August 11, 2004


The 1909 photograph shows the west side of the terminus of McCarty Glacier. In the 2004 image, the terminus has retreated about 9 miles (15 kilometers) to the north. The area in the foreground, which had been covered by glacial deposits, is now open ocean water, thanks to the melting of glacier ice under the sediment deposits. The former barren zone and adjacent hillside are now covered by dense vegetation.

U.S. Geological Survey, Department of the Interior. Earlier image by W. O. Field, courtesy of the National Snow and Ice Data Center and Glacier Bay National Park and Preserve Archive. Later image is a USGS photograph by Bruce F. Molina.

Pedersen Glacier Melt, Alaska
Summer, sometime in between mid-1920s to early 1940s – August 10, 2005


The foreground water in the earlier image is part of a lagoon, adjacent to Aialik Bay, into which Pedersen Glacier was calving icebergs. In the 2005 photograph, most of the lagoon has filled with sediment and supports grasses, shrubs and aquatic plants. The dead trees visible among the grasses are remnants of a forest that was drowned when the coast sank by some 10 feet (3 meters) during the 1964 Alaskan Earthquake. Pedersen Glacier’s terminus has retreated more than a mile (2 kilometers) and stands of trees have grown between the wetland and the glacier. The tributary high above Pedersen Glacier separated from it sometime during the third quarter of the 20th century.

U.S. Geological Survey, Department of the Interior. Earlier image is from a postcard by an unknown photographer, courtesy of Kenai Fjords National Park. Later image is a USGS photograph by Bruce F. Molina.

Heat Wave Turns Europe Brown
July 19, 2017 – July 24, 2018


The 2018 image shows portions of Denmark, Sweden, the Netherlands, Germany and Poland after a persistent heat wave turned typically green areas brown. For comparison, the 2017 image shows the same region about a year earlier. According to the European Space Agency, much of this part of the world turned brown in just a month, during which several countries experienced record high temperatures and low precipitation. The United Kingdom experienced its driest first half of summer (June 1 to July 16) on record. Read more at NASA’s Earth Observatory.

Mendocino Complex: California’s Largest Wildfire
July 26, 2018 – Aug. 11, 2018


The 2018 Ranch and River fires in Northern California are known jointly as the Mendocino Complex fire, the largest wildfire since reliable record-keeping in California began in 1932. The July image was taken the day before the fires broke out. (The reddish burn scar visible in that image is from the Pawnee fire of late June 2018.) Under hot, dry, windy conditions, the Ranch and River fires spread rapidly, burning more than 328,000 acres by the time of the August image and some 459,000 acres in all.

Images taken by Landsat 8. Source: U.S. Geological Survey’s National Land Imaging Image Collections and California Department of Forestry and Fire Protection (CAL FIRE).

Woolsey Fire, Southern California
Nov. 3, 2018 – Nov. 11, 2018


The Woolsey Fire burned some 97,000 acres of Southern California in November 2018. The large maroon patch at the bottom of the later image shows, in false color, the burn scar between Los Angeles, Thousand Oaks and Malibu. The earlier image shows the same region before the fire began. See also the Camp, Mendocino Complex, County, Thomas, and Wine Country fires.

Earlier image taken by Landsat 8, later image taken by Landsat 7. Source: U.S. Geological Survey’s Earth Resources and Science Center.

Wildfires Scorch Argentina’s Pampas Region
December 22, 2016 – January 7, 2017


Starting in mid-December 2016, roughly two dozen wildfires consumed about 2.5 million acres in the Pampas region of Argentina. Likely caused by thunderstorms following a stretch of severe drought, the first fires started southwest of the city of Bahía Blanca, as shown by small red burn scars in the Dec. 22 image (left), which cover an area of about 100,000 acres. The fires persisted despite rain at the end of December. On January 7, 2017, the Landsat 8 satellite’s Operational Land Imager (OLI) captured dramatic imagery of large burn scars across the landscape of Argentina’s central province of La Pampa, and its southern province of Rio Negro.

Samuel Dam Impact / Deforestation in Rondonia, Brazil
June 24, 1984 – August 6, 2011


The Samuel Dam is located along the Jamari River in Rondonia, Brazil. These images show the area in 1984, shortly after construction of the hydroelectric dam began, and in 2011. The reservoir created by the dam flooded the upstream forest and displaced many people. Also evident in the images is the deforestation that has affected much of the region.

Deforestation Near Pucallpa, Peruvian Amazon
November 13, 1986 – October
30, 2016


Large areas within the Amazon rainforest have undergone large-scale deforestation over the past few decades. However, in locations like the Peruvian Amazon, most of the deforestation is caused in recent years by small-scale agriculture, according to the Monitoring of the Andean Amazon Project. These images show land about 25 miles (about 40km) northwest of Pucallpa along the Aguaytia River. Lush green dominates the 1986 image (left), while deforested land is light green or pink in the 2016 image. Two large-scale oil palm plantations dominate the 2016 image.