High-latitude systems are experiencing climate change at faster rates than the rest of the globe. Warming temperatures could have dramatic effects on two important high-latitude ecological features: permafrost and soil organic thickness. Near-surface permafrost has a huge effect on surface and subsurface water flows and also sequesters carbon, which could become vulnerable to atmospheric emission with permafrost melting and degradation. A thick soil organic layer constitutes an important carbon stock and an important ecological driver: it insulates permafrost from warming effects and fav
Soil carbon and permafrost are important drivers of future greenhouse gas emissions and vegetation communities. Accurately quantifying the magnitudes and spatial distribution of these soil properties is non-trivial because they are belowground characteristics that are not evident from the surface and they are heterogeneous in nature. As part of the USGS Alaska LandCarbon assessment, USGS scientists, in collaboration with other scientists, developed a series of soil carbon and permafrost maps for Alaska.
Alaska is a major producer of base and precious metals and has a high potential for additional undiscovered mineral resources. However, discovery is hindered by Alaska’s vast size, remoteness, and rugged terrain. Hyperspectral remote sensing is one method that can be used to rapidly acquire data about the distributions of surficial materials, including different types of bedrock and ground cover.
Global warming is rapidly thawing permafrost along the Arctic Coastal Plain of northern Alaska, with a cascading effect that results in coastal subsidence, inundation by salt water, and subsequent changes to habitat distribution and quality. As part of the USGS Changing Arctic Ecosystem Initiative, scientists at the Alaska Science Center are using WorldView-2 and -3 satellite imagery to map changes taking place to goose “grazing lawn” (GL) habitat (http://pubs.usgs.gov/fs/2014/3088/). In the figure, the class “GL Transition” represents tun
Wildfire disturbance is an important factor contributing to ecosystem and landscape changes. The impact of fires on permafrost-influenced terrain in boreal forest regions is well documented; however, the role of fires in initiating thermokarst development in arctic tundra regions is poorly understood. Rapid climate change at high latitudes has increased interest in the spatial and temporal dynamics of thermokarst and other permafrost thaw-related features in diverse disciplines including landscape ecology, hydrology, engineering, and biogeochemistry. As a result, there is an urgent need
USGS scientists have been involved in mission planning, cartographic data processing, and scientific studies for the international Cassini-Huygens mission to the Saturn system since its inception in the early 1990s. Saturn’s Mercury-sized moon Titan, which has a range of geological features and processes unmatched by any other body besides the Earth, has been the main focus of these efforts.
The first global topographic map of Mercury has been released by the USGS Astrogeology Science Center, in collaboration with Arizona State University, Johns Hopkins University Applied Physics Laboratory, Carnegie Institute of Washington, and NASA. This map provides the first comprehensive view of Mercury’s entire surface illustrating the geologic and tectonic characteristics of the planet closest to the sun.
The High Resolution Imaging Science Experiment (HiRISE) camera on board the Mars Reconnaissance Orbiter captures the surface of Mars at higher resolutions than ever before obtained from an orbiter: image pixel sizes are as small as 25 cm. The capacity to deliver fine-scale detail serves one of the major science objectives of HiRISE, which is to track changes in Martian surface features.
The solar system is full of objects (“small bodies”) that include comets, asteroids, and dwarf planets. Many of these small bodies are relics from the early solar system and therefore provide clues about the early solar system and the formation of the planets. These small bodies are also potentially resource rich, e.g. water ice, and could support future human missions. The USGS is actively involved in several missions to understand these small bodies, including the Dawn mission to Ceres, the New Horizons flyby of Pluto, and the Japanese mission Hayabusa-2.
Color views of the Moon have revealed substantial distributions of water on the lunar surface in the form of molecules trapped in minerals. This discovery has fundamentally changed the prevailing view of the Moon as a sterile object. The USGS is supporting further analyses of lunar water by producing a high-precision cartographic mosaic from data collected by the NASA Moon Mineralogy Mapper (M3) instrument. These products include geodetically controlled, near-global maps of the lunar surface in visible to near-infrared wavelengths.