This article concerns navigation in the sense of determination of position and direction on the surface of the Earth. See navigation (disambiguation) for other meanings.

The word navigation is derived from the Sanskrit word navgatih. There are several traditions of navigation. The art of navigation was born in the river Indus in India over six thousand years ago. In the pre-modern history of human migration and discovery of new lands by navigating the oceans, a few peoples have excelled as sea-faring explorers. Prominent examples are the Phoenicians, the Ancient Greeks, the Malays, the Persians, Arabians, the Norse and, perhaps more than any others, the peoples of the Pacific Ocean, particularly Polynesians and Micronesians.

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USGS Newsroom

Coast Salish and USGS Commit to Restoring Salish Sea Water Quality
OC_Web@usgs.gov (Office of Communications Web Group)Reporters: Want to interview a Tribal Skipper or scientist along the journey? Contact Jennifer or Charlie (contacts listed above). Follow the Tribal Journey's progress through press releases, maps, videos and photos by visiting www.usgs.gov/coastsalish. The Coast Salish Nation and the U.S. Geological Survey (USGS) will embark on a Canoe Journey to study and improve water resources in the Salish Sea, July 8-29. Water quality has deteriorated significantly across Puget Sound and the Strait of Georgia in recent decades and threatens most nearshore and marine habitats and ecosystem functions. This is the only year so far that a scientific component has been added to the Coast Salish Annual Tribal Journey. For the first time, water quality surveys will be simultaneously conducted behind multiple canoes to show variations in a broad area crossing international borders. This project will blend traditional knowledge of the Coast Salish People with USGS science in an effort to help improve management of ancestral waters experiencing environmental decline. "Over the last 100 years, people have looked at our most sacred site (the Salish Sea) as a dump site," said Swinomish Chairman Brian Cladoosby. "You have everything - heavy metals, toxins, farm runoff, nonpoint pollution - and it ends up in the Salish Sea. It's up to this generation and future generations to make everyone aware of the conditions. We as Coast Salish have decided no more and we are stepping forward to restore and protect our most precious waters of the Salish Sea." During the journey, members of western Washington Tribes and British Columbia First Nations will travel in more than 100 canoes from locations throughout Washington and British Columbia to Cowichan First Nation in Duncan, B.C. Five of those canoes will carry water-quality probes and Global Positioning System (GPS) units. Canoes are ideal because they are slow moving and do not add any toxins to the environment. The probes will measure specific water quality components including; surface-water temperature, salinity, pH, dissolved oxygen, total dissolved solids, and turbidity.  The project is coordinated by the Swinomish Tribe and lead by Sarah Akin, a scientist with the Tribe for three years. USGS scientists Eric Grossman and Paul Schuster have been invited by the Coast Salish to participate as science advisors to provide technical expertise in planning and conducting the study and analyzing the data.  "The Coast Salish have extensive traditional ecological knowledge of their environment and patterns of change across the Salish Sea," said Grossman. "This project will provide a unique opportunity to improve understanding of ongoing change to the region's ecologic and cultural resources and the processes that affect them." The collected data will provide an informational snapshot of conditions that can be compared with future canoe journey measurements that will help Tribal, Federal, State, and local entities identify water-quality issues and ultimately manage Salish Sea resources. Follow the Tribal Journey's progress through press releases, maps, videos and photos by visiting www.usgs.gov/coastsalish The project is supported through the Swinomish Indian Tribal Community, Northwest Straits Commission, USGS and the Potlatch Fund. For information on the Coast Salish Project or to learn more about the history, peoples, and mission of the Coast Salish visit http://www.coastsalishgathering.com/. For a podcast interview on the Tribal Journey, listen to episode 52 of CoreCast at http://www.usgs.gov/corecast/.
July Science Picks — Leads, Feeds and Story Seeds
OC_Web@usgs.gov (Office of Communications Web Group)In this edition of Science Picks, learn about an upcoming Canoe Journey to study water resources in the Salish Sea, a new USGS partnership to develop a volcano early warning system in Chile, how California sea otter populations are recovering at a slow rate and what the odds are of a 500-year flood in the Midwest. Discover what makes an old geyser faithful, a recent finding that may help explain the solar system's formation and new research on the sage-grouse's chances for survival. As Independence Day approaches, many will ask what makes the colors in fireworks so vivid. Learn the answer to this and much more! If you would like to receive Science Picks via e-mail, would like to change the recipient, or no longer want to receive it, please e-mail jrobertson@usgs.gov. July Highlights: Tribal Canoe Journey to Help Restore Salish Sea Resources USGS to Help Chile Develop Volcano Early Warning System California Sea Otters: Population Recovery Continues at Slower Rate Two 500-Year Floods Within 15 Years: What are the Odds? What Makes an Old Geyser Faithful? One Step Closer to Understanding the Solar System's Formation Chances for Sage-Grouse Survival: New Model Explains Population and Habitat Trends What Makes the Colors in Fireworks? USGS Helps the Phoenix Mars Lander Safely Land Stalking Snakes: On the Prowl for Invasive Species National Treasure Expands: National Archives to Include Earth Imagery Water Science for Schools Now Available in Chinese Hair Sheds Light on Elusive Carnivores
USGS Accelerates Access to Satellite Data
OC_Web@usgs.gov (Office of Communications Web Group)Federal and state agencies that need satellite imagery from commercial sources will find it much easier to acquire the data through a streamlined process managed by the U.S. Geological Survey. Many federal and state agencies rely on imagery of the earth acquired by commercial satellites to conduct missions related to natural hazard response, resource management, crop monitoring and climate change studies. These agencies can now meet their requirements by working through USGS multiple-award contracts rather than individual vendor contracts, saving the agencies considerable time and money. Five commercial satellite data contracts will enhance the variety of current satellite imagery available to federal and state agency partners by providing multi-resolution, all-weather radar and multispectral imaging capabilities. The five commercial data contracts were awarded to EADS North America of Arlington, Va.; DMC International Imaging of Surrey, United Kingdom; GeoEye of Dulles, Va.; DigitalGlobe of Longmont, Colo.; and SPOT Image Corporation of Chantilly, Va. Interested federal and state agencies may contact Sandra Lintz, (303) 236-9560 or slintz@usgs.gov, for commercial satellite data ordering and product information or to discuss their specific imagery information needs. Additionally, all satellite data users, including the general public, will benefit from a recent USGS policy change making the entire Landsat data library available through USGS Web portals at no cost to the user. Further information about no-cost historical Landsat data products is available at http://landsat.usgs.gov/. For additional information on USGS Land Remote Sensing, please visit http://remotesensing.usgs.gov/.
USGS to Help Chile Develop Volcano Early Warning System
OC_Web@usgs.gov (Office of Communications Web Group)Notas: Artículo de noticias disponible en Español The U.S. Geological Survey is partnering with the Chilean government to develop a volcano early warning and emergency response system for the country after the historic eruption of Chaitén Volcano on May 2. Following the eruption, the USGS helped Chile to install monitoring networks at Chaitén to transmit data in real time and help warn the public of further eruptions. On June 13, the USGS signed a letter of intent with President Bachelet of Chile to help the nation establish a volcano early warning system. Related Podcasts USGS to Help Chile Develop Volcano Early Warning System Download directly | Details   or subscribe by e-mail. "There was virtually no instrumental monitoring at Chaitén Volcano prior to the eruption," said USGS scientist John Ewert, who noted that 5,000 residents were evacuated from areas near the volcano. "Without the monitoring, people nearby or at risk have almost no time to prepare themselves, their families or their possessions for what may be a life-altering event." "The Chaitén Volcano is continuing to build a lava dome at a spectacular rate, to emit fine ash, and to produce lahars - rivers of mud and debris - that continue to flow through the town of Chaitén," said USGS scientist Andy Lockhart, who was on the ground at Chaitén. Chile's volcano early warning system will be modeled after a plan the USGS released in 2005 in the United States that systematically ranks the most dangerous volcanoes and assesses monitoring gaps at each volcano. The United States has a total of 169 potentially active volcanoes, half of which have some monitoring, and five volcano observatories nationwide. Chile has 120 potentially active volcanoes and one volcano observatory for the nation. The work in Chile was done with support from the U.S. Agency for International Development (USAID) Office of Foreign Disaster Assistance, and future work will be coordinated through the Volcano Disaster Assistance Program, a 22-year collaborative project between the Office of U.S. Foreign Disaster Assistance and the USGS. "Fundamentally, we build friendships with our colleagues and partners around the world and together we are better able to mitigate these potentially dangerous events," said USGS scientist John Pallister. Listen to episode 51 of CoreCast to hear a podcast interview with volcanologists Pallister, Ewert and Lockhart.
Larsen Named USGS Associate Director for Water
OC_Web@usgs.gov (Office of Communications Web Group)Dr. Matthew C. Larsen has been named Associate Director for Water of the U.S. Geological Survey (USGS).                          In his Associate Director role, Dr. Larsen has programmatic responsibility for all water-related research and activities at the USGS. He will be responsible for water issues relating to flooding, water quality, drought, climate change and water availability. Larsen has been the leader of the USGS National Research Program in hydrology in his position of Chief Scientist for Hydrology since 2005.  "Matt has an outstanding record as a research scientist, advancing knowledge of hydrologic and landslide processes in tropical ecosystems. He has worked closely with the National Science Foundation on collaborative efforts in water research and has directed USGS hydrologic research in advancing the understanding of the impacts of climate change on hydrologic systems," said USGS Director Mark Myers.  As USGS Caribbean District Chief, Larsen supervised water resources programs and worked with external partners in Puerto Rico and the U.S. Virgin Islands starting in 2000. That same year he also served as a coordinator and researcher on a USGS international mission that responded to the December 1999 landslide and flashflood disaster in Venezuela. Larsen was the Luquillo, Puerto Rico, Water, Energy, and Biogeochemical Budget project chief from 1991 to 2000. Prior to that, he was project chief on a USGS study of landslide hazards in eastern Puerto Rico. Larsen began his USGS career in 1977 with the Branch of Pacific and Arctic Marine Geology, Menlo Park, CA. He was a physical science technician and participated in a study of natural hazards to petroleum development in the Northern Bering Sea, Alaska. Dr. Larsen earned a bachelor's in Geology in 1976 from Antioch College in Yellow Springs, Ohio, and a doctorate in Geography at the University of Colorado-Boulder in 1997. He is also the Chair of the U.S. National Committee for the UNESCO International Hydrological Programme and is the author of 66 scientific reports and journal articles.
California Sea Otters: Population Recovery Continues at Slower Rate
OC_Web@usgs.gov (Office of Communications Web Group)Editors' note: Graphs, maps and other information on spring surveys of the California sea otter population are online at: http://www.werc.usgs.gov/otters/ca-surveys.html  The southern sea otter of California, a threatened population on the Endangered Species list, continues to recover, but the rate of recovery appears to have slowed. USGS scientists say the latest 3-year average (2,826 sea otters) was 0.3 percent higher than last year's 3-year average, representing a slower rate of increase than they have seen in recent averages. Scientists use 3-year running averages of spring census totals to assess population trends because these averages are more reliable than individual year totals. For southern sea otters to be considered for delisting, the 3-year running averages would have to exceed 3,090 for 3 continuous years, according to the U.S. Fish and Wildlife Service's Southern Sea Otter Recovery Plan. Differences in weather conditions, otter distribution and other factors contribute to the year-to-year variance in survey numbers. The latest 3-year average was obtained by combining the spring census totals from the years 2006, 2007 and the recently completed spring 2008 census. During the 2008 census, observers counted 2,760 California sea otters, 8.8 percent fewer than the 2007 spring count of 3,026.   "Because of the inherent variability in the surveys, the lower count this spring is not alarming to me. But what does raise an eyebrow is the leveling off of the 3-year average," said survey organizer Brian Hatfield, a USGS biologist in California. "As usual, the next spring sea otter survey or two will tell us more about the current population trend." "The population dynamics are actually quite variable across the range," said Dr. Tim Tinker, lead scientist for the USGS sea otter research program in California. "Over the last 5 years we have seen relatively high growth rates at the southern end of the range, and to a lesser extent at the northern range periphery, but we have seen very low or negative growth in the center portion of the range where sea otter densities are highest and where most of the reproduction occurs." "This year's census results highlight the need for continued attention to the recovery of this threatened sub-species, and the importance of targeted research and recovery actions," added Tinker. Ongoing collection and analyses of demographic data by USGS scientists are aimed at understanding the underlying reasons for the sluggish rate of recovery and variable population trends. Some of the variation in numbers at smaller scales reflects movements of animals between areas, especially in the case of males. For example, numbers were lower this year in Estero Bay, but higher between Pismo Beach and Pt. Sal. USGS studies of radio-tagged animals have shown that males frequently make long-distance movements between sandy embayments such as Estero Bay, Pismo Beach and Monterey Bay. Additionally, the population distribution has expanded farther to the north and south, and now stretches from Tunitas Creek mouth, in San Mateo County, south to Coal Oil Point, in Santa Barbara County.  The rate of expansion at the south end of the range continues to outstrip the northward range expansion. "Range expansion is clearly important for population growth and recovery," said Lilian Carswell of USFWS, "and it can also give us insight into how sea otters benefit from or are harmed by environmental factors that differ from those in the center of the range. Comparative studies between these areas can yield information on the dynamics that are affecting population growth and point to needed management actions." The spring 2008 California sea otter survey was conducted May 2-24 over about 375 miles of California coast. The census results provide counts used to evaluate trends, and are not absolute population estimates. The census is a cooperative effort of the USGS, California Department of Fish and Game's Marine Wildlife Veterinary Care and Research Center, Monterey Bay Aquarium, and many experienced and dedicated volunteers. The information gathered from spring surveys is used by federal and state wildlife agencies in making decisions about the management of this small sea mammal.

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