Images

Contour plots of SSC for the spatial surveys during trade-wind conditions on the reef flat. (a) SSC from the low tide survey. The highest SSC (60e70 mg/l) were located in a nearshore band, and east of the fish ponds and Kaunakakai wharf. (b) SSC from the high tide surveys.

Jeff Hansen on an all-terrain vehicle (ATV) at Ocean Beach, San Francisco, in 2006. The ATV is equipped with instrumentation which records beach topography.

Photograph of Pingok Island, Alaska, reveals physical features of a changing Arctic: collapsing bluffs, salt-killed tundra (lighter brown near the bluff edge), and drained thermokarst lakes (rust-colored depressions).

An oblique aerial photograph shows the currently active Long Range Radar Site on Barter Island, formerly a DEW Line (Distant Early Warning) station that was deactivated in 1990. The Cold War-era landfill in the foreground of the photograph was at immediate risk from coastal erosion in 2006 and has since been relocated farther inland.

This photograph shows the Arctic Coastal Plain of northern Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shoreline habitats and nearby Native communities.

Photograph of barrier islands near the western terminus of Icy Reef located on the Beaufort Sea coast of Alaska, looking south. Egaksrak Lagoon separates the islands from the low-lying mainland coast of the Arctic National Wildlife Refuge and the Brooks Range in the background.

This photograph shows ice-wedge polygons and an eroding shoreline at Cape Halkett on the Beaufort Sea coast of Alaska. Coastal erosion along the Arctic coast is chronic, widespread, and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shoreline habitats, and nearby Native communities.

Coral atolls are normally long, thin bars of white sand that rise just a few meters above sea level. The island or island group surrounds a hollow center where a volcanic peak once was. The atoll shown in this photo-like satellite image is the island of Tureia, in French Polynesia, in the South Pacific Ocean.

Photo of Dinkey Creek in the southern Sierra Nevada, California, showing a small waterfall cascading down a bedrock slope.

Landsat image of Maui, Hawaiʻi, with the small island of Kahoʻolawe to its south.

Personal watercraft equipped with GPS and sonar (echo sounder) is used to collect detailed, nearshore bathymetry (depth) information.

USGS scientists Andrew Schwartz and Dan Hanes maneuver a current profiler for a study of surf-zone hydrodynamics at Ocean Beach, on the west side of San Francisco, California. Beach erosion has been a continuing problem in this area.

Sonar-generated image showing underwater topography and the potential for landslides near the head of Resurrection Bay, Alaska. The terrain looks three times as steep as it occurs naturally. The arrow points to underwater landslide debris from the collapse of a fan-delta following the great Alaskan earthquake of 1964.

Tsunami wave field in the Bay of Bengal one hour after the M=9.1 Sumatra-Andaman earthquake on December 26, 2004. View looks to the northwest.

A field of giant sand waves, among the largest in the world, at the mouth of San Francisco Bay in California.

Large-scale poster describing USGS work.

USGS scientists needed a better way to measure river sand in the Grand Canyon. Traditionally, scientists used a bucket to get about 75 sand samples on each trip, which were analyzed weeks later in a lab.

Large-scale poster describing USGS work.

Large-scale poster describing USGS work.

The USGS, in cooperation with the Upper Yuba River Studies Program and the California Bay–Delta Authority (CALFED), studied Englebright Lake. Englebright Dam was built in 1941 to trap sediment washed downstream by hydraulic gold mining.

Homes along the edge of the coast in Isla Vista, California, Santa Barbara County, face a short lifespan because of eroding bluffs that support them.

Stromatolites growing in Hamelin Pool Marine Nature Reserve, Shark Bay in Western Australia. Photo by Paul Harrison, Reading, UK, CC BY-SA 3.0

An International Tsunami Survey Team studying the effects of the December 26, 2004 tsunami on Indonesia“‘’’s island of Sumatra documented wave heights of 20 to 30 m (65 to 100 ft) at the island's northwest end and found evidence suggesting that wave heights may have ranged from 15 to 30 m (50 to 100 ft) along at least a 100-km (60 mi) stretch of the northwest coast.