red in the Cascade Mountains near Oso, Washington. Triggered by heavy rains, the slide covered the North Fork of the Stillaguamish River and destroyed numerous homes. After a week of intensive search and rescue efforts, at least 20 deaths had been reported and many others were still reported missing. The muddy debris also created a dam that blocked the river, causing concerns for flooding and flash flooding as the water filled behind and moved around the dam.
These images were acquired by Landsat 8 on January 18, 2014, and again on March 23, 2014. Along with the landslide, the barrier lake caused by the blocked river channel can also be seen in the later image.
Landsat imagery will be useful (along with other datasets) as the efforts to recover, reclaim, and restore this area are implemented.
These Landsat images show the Sesan River (Tonlé San), which runs through the boundary region between northeast Cambodia and Vietnam. The river forms an important tributary to the Mekong River, which lies to the west (not shown). The two images were acquired in 1989 (left) and again in 2014 (right).
These images are “false-color composites.” The red tones are due to a strong signal from Landsat’s near-infrared (NIR) band, which is often used by landscape scientists to monitor the presence and condition of vegetation and forested areas. The lighter tones in the 2014 image show where vegetation has been cleared for logging, mining, or other land use purposes.
The Yali (Yaly) Falls Dam was built in 1993–1996, and its associated reservoir can be seen on the right side of the 2014 image.
The information contained in images such as these can be used to understand the landscape conditions at any location worldwide, and the 40-year record of Landsat allows scientists and others to monitor changes to this landscape over time.
Yarki Island and Lake Baikal, Russia March 14, 2014
Located in southern Siberia in Russia, Lake Baikal is the deepest lake in the world (1,700 m) and contains 20 percent of the fresh surface water on the planet. Because of its geologic age and geographic isolation, more than 80 percent of the lake’s freshwater species are found only at Lake Baikal.
A narrow sand spit stretches across the lake’s north end to form Yarki Island, which separates the northernmost shoreline from the open water. This long, discontinuous land surface is the result of accumulated sediments from several rivers flowing in from the north, combined with the interaction of these sediments with incoming waves, wind, and storms from the main lake to the south. The shallow lagoon that is created behind Yarki Island is filled with relatively warm waters and peat deposits, and forms an important bird sanctuary.
This Landsat image shows the area around Yarki Island and northernmost Lake Baikal. The green tones in the lagoon area depict vegetative sediments. The mouth of the Verkhnaya Angara River can be seen on the right side of the image.
The vast archive of Landsat images helps researchers and scientists monitor the Earth’s ecosystems, and provides unbiased evidence of how changes can affect these ecosystems worldwide.
Near the southernmost tip of Africa lies the Sundays River Valley, an agricultural area rich in citrus fruit production. Urban settlements and orchards in the subtropical climate are aided by a well-developed irrigation system that was established in the early 1920s with the construction of a dam upstream of the area shown in these images.
These Landsat images show the Sundays River Valley area in November 1986, and again the same month in 2013. Orchards can be seen expanding along both sides of this stretch of river. The bright green colors indicate orchards and agricultural lands, and pinkish hues indicate unused parcels.
Landsat imagery is valuable for measuring and monitoring land use and land use changes across the Earth’s landscape.
These Landsat images show portions of the Cordoba and San Luis provinces in central Argentina. The urban area to the right of image center is Villa Dolores. To the north and east of the urban area, the Em