are useful for space-based mapping and classifications of vegetation, ecosystems, and coastal habitats.
Mount Tavurvur erupted on August 29, 2014, sending ash over surrounding areas on Papua New Guinea’s New Britain Island. The stratovolcano is located along the eastern edge of the Rabaul Volcanic Complex, and its last major eruption was in 1994.
These two Landsat images were acquired in April and September 2014. In both images, Mount Tavurvur can be seen to the east side of Simpson Harbor. This harbor forms part of the much larger (mostly submerged) Rabaul Caldera.
The second image was acquired a few days after the August 2014 eruption. This image shows the extent of ashfall (gray-brown), while the forested areas that were less affected by ash remain green.
Images acquired by the Landsat satellites are useful for monitoring land changes and recovery after natural disasters such as volcanoes.
Oil Production near Tioga, North Dakota August 28, 2014
These Landsat images show the area around Tioga, North Dakota, in 2002 and again in 2014. Oil was first discovered near Tioga in 1951, and the town has experienced several episodes of rapid growth due to its location over the Williston Basin, a major North American geologic source of oil, natural gas, and other energy resources. The recent development of advanced drilling techniques has led to a new surge of production, particularly within the Bakken Formation, which has become an important source of oil within the United States.
These two Landsat images show the dramatic changes to the landscape near Tioga in recent years. Many new oil wells and related facilities (small bright features) are visible in the 2014 image compared to the earlier image. The rapid expansion of the town of Tioga can also be seen, as the town has grown to support an expanding workforce. The 2014 image also shows the development of new oil processing and transportation facilities along the western and eastern edges of Tioga.
The images from the Landsat archive span four decades and provide a consistent worldwide record of land use and land cover changes as they occur across the Earth’s surface.
Urban Expansion of Shenyang, China August 22, 2014
The city of Shenyang is one of the largest cities in northeastern China. Situated along the Hun River, the city is a major transportation hub. It is also an important industrial center, representing the core city of the Shenyang Economic Zone. Its urban and outlying areas are home to over 8 million people.
These images show the city of Shenyang in 1984, and again in 2014. The expansion of Shenyang’s urban area over the past 30 years is striking, as the urban developed area (shades of silver and gray) has expanded into the previous farmland and forested areas (green shades) surrounding the city. The large green feature in the north-central part of the urban area is Beiling Park, the largest park in the city.
The 40+ year archive of Landsat imagery provides a valuable tool for recording urban growth and other types of land cover change over time. The information in these images can also be useful for monitoring the effects of urban growth on the surrounding landscape and ecosystems.
Dam Breach at Mount Polley Mine, Canada August 13, 2014
On August 4, 2014, an earthen dam failed at the Mount Polley Mine in central British Columbia, Canada. The dam had been built to hold a tailings pond that contained water and waste materials from local gold and copper mining operations.
The tailings pond covered over 4 square kilometers and within a few days, millions of cubic meters of wastewater and slurry had flowed from the pond into neighboring Polley Lake, Hazeltine Creek, and Quesnel Lake.
These two Landsat images show the area of active mining and associated tailings pond. In both images, the dark areas indicate clear water. The suspended materials within the tailings pond (first image) are more reflective, so this water appears brighter. In the August 6 image, the waste materials from the tailings pond can be seen (blue, green, and silver) flowing down Hazeltine Creek and 