impanzee habitat, which is closely correlated with topography. The map helps scientists visualize the resources within the reserve and the mounting human pressure on the natural landscapes that surround it.
The Landsat 8 image (left) of the study area coupled with the SRTM 30-meter data (center) provides a specialized view of the topography. The land cover map (right) shows the diverse habitats, including the locations of gallery forests. These narrow ribbons of dense trees follow watercourses and are indicated as purple shades on the land cover map. Gallery forests provide critical refuge for many species of plants and animals during the long, hot dry season. The maps are being used in a proposal by the Jane Goodall Institute to Senegal and Guinea to extend the Dindefelo Nature Reserve south into the Guinea highlands.
Mapping these biodiverse highlands is one example that demonstrates the advantage of the more accurate elevation data from SRTM. For more information, see the USGS Top Story here.
Detailed Elevation Data—Niger River Delta September 23, 2014
Shuttle Radar Topography Mission (SRTM) data had previously only been available worldwide at 90-meter resolution. The National Geospatial-Intelligence Agency (NGA), NASA, and USGS are now releasing a newly processed, global SRTM 30-meter dataset.
The above images show an example of the difference between the 90-meter and 30-meter data of the Niger River Delta in western Africa. The Landsat image, also at 30-meter resolution, of the same area shows the extensive coastal estuaries, tidal flats, mangrove forests, and lowland rainforests of this part of southern Nigeria. More detailed elevation data are especially critical in such coastal settings that have small elevation changes.
For more information on the new SRTM elevation product, see the USGS Top Story here.
Coastal Flooding near Semarang City, Indonesia September 19, 2014
Coastal inundation is an ongoing concern for the region near Semarang, Indonesia. This area faces several different types of flood risk, due to the potential combination of high tides, seasonal rainfall events, and river flooding. Much of this low-lying area is only 0–25 meters above sea level, and in some areas, land subsidence has also been occurring for many years. All of these factors lead to a risk of coastal flooding for local populations.
These Landsat images indicate changes in the area near Semarang City over the past 20 years. Semarang City is located at the bottom center of these images, and the differences along the coastline are particularly visible northeast of the city. In particular, the 2014 image shows coastal inundation that is encroaching on populated areas, roads, and structures.
Disaster managers and risk reduction personnel rely on satellite imagery such as Landsat to help document and mitigate flood threats as effectively as possible. The 42-year archive of Landsat imagery also provides a historical record that can be used to indicate long-term changes as they occur in coastal areas. This can help scientists and engineers understand and analyze historical trends, and assist with future planning for flood management and mitigation.
The Zapata Peninsula is located in western Cuba. Most of this sparsely populated area lies within the Ciénaga de Zapata National Park and UNESCO-designated Biosphere Reserve.
The region is covered by large areas of open swamp and marshes intermixed with dense woodlands. It is also home to one of the largest coastal wetlands in the Caribbean region. The extensive and fragile ecosystem is protected for its biodiversity and high concentration of migratory birds, mangrove forests, seagrass beds, and coral reefs.
This Landsat 8 image shows the peninsula and neighboring region. The dense forests are dark green, while the open swamps and marshlands are shown in brighter green and yellow tones. This image also shows the surrounding deep ocean water and channels (dark blue and black), along with shallow water and coral reefs (bright blue).
Landsat images provide a valuable record of the earth’s surface and 