Salem, Oregon Salem () is the capital of the U.S. state of Oregon, and the county seat of Marion County. It is located in the center of the Willamette Valley alongside the Willamette River, which runs north through the city. The river forms the boundary between Marion and Polk counties, and the city neighborhood of West Salem is in Polk County. Salem was founded in 1842, became the capital of the Oregon Territory in 1851, and was incorporated in 1857. Salem,_Oregon
Phoenix, Arizona Phoenix (, O'odham Skikik, Yavapai Wasinka, Western Apache Fiinigis, Navajo Hoozdo, Mojave Hachpa 'Anya Nyava) is the capital and largest city in the U.S. state of Arizona, as well as the fifth most populous city in the United States. Phoenix is home to 1,552,259 residents, and is the anchor of the Phoenix Metropolitan Area, the 12th largest metro area by population in the United States with 4,281,899 residents. Phoenix,_Arizona
Aurora (astronomy) Auroras, sometimes called the northern and southern (polar) lights or aurorae (singular aurora), are natural light displays in the sky, usually observed at night, particularly in the polar regions. They typically occur in the ionosphere. They are also referred to as polar auroras. Aurora_(astronomy)
Polar climate polar climate are characterized by a lack of warm summers (specifically, no month having an average temperature of 10 °C or higher).The tundra covers over 20% of the earth. The sun shines 24 hours in the summer, and barely ever shines at all in the winter (see midnight sun). Polar_climate
Flood In the sense of "flowing water", the word may also be applied to the inflow of the tide.Flooding may result from the volume of water within a body of water, such as a river or lake, which overflows or breaks levies, with the result that some of the water escapes its normal boundaries. Flood
Phytoplankton Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words phyton, or "plant", and πλαγκτος ("planktos"), meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye. Phytoplankton
Zooplankton Zooplankton are the heterotrophic (sometimes detritivorous) type of plankton. Plankton are organisms drifting in the water column of oceans, seas, and bodies of fresh water. The name of zooplankton is derived from the Greek zoon (), meaning "animal", and 'naked eye. Zooplankton
Paleoclimatology Paleoclimatology (also Palaeoclimatology) is the study of climate change taken on the scale of the entire history of Earth. It uses records from ice sheets, tree rings, sediment, and rocks to determine the past state of the climate system on Earth. Paleoclimatology
Side-scan sonar Side-scan sonar (also sometimes called side scan sonar, sidescan sonar, side looking sonar, side-looking sonar and bottom classification sonar) is a category of sonar system that is used to efficiently create an image of large areas of the sea floor. This tool is used for mapping the seabed for a wide variety of purposes, including creation of nautical charts and detection and identification of underwater objects and bathymetric features. Side-scan_sonar
Underwater archaeology Underwater archaeology is the study of past human life, behaviours and cultures using the physical remains found in salt or fresh water or buried beneath water-logged sediment. It is most often considered as a branch of maritime archaeology. Due to the difficulties of accessing underwater sites, the application of archaeology to underwater sites emerged from the skills and tools developed by salvagers, and underwater archaeology initially struggled to establish itself as proper archaeological research. Underwater_archaeology
Albany, New York Albany is the capital of the state of New York and the county seat of Albany County. Albany is roughly 136 miles (219New York, and slightly south of the confluence of the Mohawk and Hudson Rivers. The city sits on the Hudson River and has a major port. The Hudson River has been deepened so that ocean-going ships can reach the city. As of July 2007, the city had an estimated population of 94,172. Albany,_New_York
Inversion (meteorology) In meteorology, an inversion is a deviation from the normal change of an atmospheric property with altitude. It almost always refers to a temperature inversion, i.e., an increase in temperature with height, or to the layer (inversion layer) within which such an increase occurs. Inversion_(meteorology)
Milwaukee Milwaukee is the largest city in Wisconsin and 23rd largest (by population) in the United States. It is the county seat of Milwaukee County and is located on the southwestern shore of Lake Michigan. As of the 2000 census, the city had a population of 596,974. Milwaukee
Richmond, Virginia This article is about the city of Richmond, the capital of the Commonwealth of Virginia. For information on Richmond County, which is away and unrelated to the city, please see Richmond County, Virginia.Richmond () is the capital of the Commonwealth of Virginia, in the United States. Richmond,_Virginia
San Jose, California San Jose () (meaning St. Joseph in Spanish) or San José is the third-largest city in California and the tenth-largest in the United States. The county seat of Santa Clara County, it is located at the southern end of the San Francisco Bay Area, a region commonly referred to as Silicon Valley. San_Jose,_California
Narwhal The narwhal (Monodon monoceros) is a medium-sized toothed whale that lives year-round in the Arctic. One of two species of whale in the Monodontidae family, along with the Beluga whale, the narwhal males are distinguished by a characteristic long, straight, helical tusk extending from their upper left jaw. Narwhal
Salt Lake City Salt Lake City is the capital and the most populous city of the U.S. state of Utah. The name of the city is often shortened to Salt Lake or SLC. Salt Lake City has a population of 180,651 as of 2007. The Salt Lake City metropolitan area spans Salt Lake, Summit and Tooele counties, and has a total estimated population of 1,099,973. Salt_Lake_City
Galveston, Texas Galveston () is a city in and seat of Galveston County located on Galveston Island on the Gulf Coast in the U.S. state of Texas within the metropolitan area. As of the 2005 U.S. Census estimate, the city had a total population of 57,466. Galveston is accessible by the Galveston Causeway linking Galveston Island to the mainland on the north end of the city, a toll bridge on the western end of the island, and by ferry boat service on the east end of the city. Galveston,_Texas
Miami Miami ( or ) is a coastal city in southeastern Florida, in the United States. Miami is the county seat of Miami-Dade County, the most populous county in Florida. With an estimated population of 409,719 in 2007, Miami
San Antonio San Antonio (pronounced /ˌsænænˈtoʊnioʊ/) was named for the Portuguese St. Anthony, whose feast day is on June 13, when a Spanish expedition stopped in the area in 1691. Located in the northern part of and the , San Antonio is the epicenter of Tejano culture and Texas tourism. San_Antonio
Dew point dew point is the temperature to which a given parcel of air must be cooled, at constant barometric pressure, for water vapor to condense into water. The condensed water is called dew. The dew point is a saturation point.When the dew point temperature falls below freezing it is often called the frost point, as the water vapor no longer creates dew but instead creates frost or hoarfrost by deposition. Dew_point
Younger Dryas Younger Dryas stadial, named after the alpine/tundra wildflower Dryas octopetala, and also referred to as the Big Freeze, was a geologically brief (approximately 1,300 ± 70 years) cold climate period following the Bölling/Allerød interstadial at the end of the Pleistocene between approximately 12,800 to 11,500 years ago, and preceding the Preboreal of the early Holocene. Younger_Dryas
Wildfire A wildfire is any uncontrolled, non-structure fire that occurs in the wilderness, wildland, or bush. Other names such as wildland fire, forest fire, brush fire, vegetation fire, grass fire, peat fire, bushfire (in Australasia), and hill fire are commonly used. Wildfire
Tucson, Arizona Tucson ( or /tuksʊn/ in Spanish) is a city in and the county seat of Pima County, Arizona, United States, located 118 miles (188 km) southeast of Phoenix and 60 miles (98U.S.-Mexico border. As of July 1, 2006, a Census Bureau estimate puts the city's population at 525,529, with a metropolitan area population at 1,023,320 as of July 1, 2008. Tucson,_Arizona
Monsoon monsoon is a seasonal prevailing wind that lasts for several months. The term was first used in English in India, Bangladesh, Pakistan, and neighboring countries to refer to the big seasonal winds blowing from the Indian Ocean and Arabian Sea in the southwest bringing heavy rainfall to the area. Monsoon
Tallahassee, Florida Tallahassee () is the capital of the State of Florida, USA, and the county seat of Leon County. Tallahassee became the capital of Florida in 1824. In 2007, the population recorded by the U.S. Census Bureau was 168,979 , while the 2007 Tallahassee metropolitan area is estimated at 353,425.Tallahassee is the home of Florida State University, Florida A&M University, Tallahassee Community College and branches of Barry University, and Flagler College. Tallahassee,_Florida
Topeka, Kansas Topeka (Kansa:Tó Ppí Kˀé) is the capital city of the U.S. state of Kansas and the county seat and most populous city of Shawnee County. It is situated along the Kansas River in the central part of Shawnee County, located in northeast Kansas, in the Central United States. Topeka,_Kansas
Oklahoma City Oklahoma City is the capital and largest city of the U.S. state of Oklahoma. The county seat of Oklahoma County, the city ranks 31st among United States cities in population. The city's estimated population as of 2006 was 537,734, with a 2008 estimated population of 1,206,142 in the metropolitan area. In 2008, the Oklahoma City-Shawnee Combined Statistical Area had a population of 1,275,758 residents. Oklahoma_City
Pago Pago Pago Pago ( in English, but by native Samoan speakers) is the capital town of American Samoa. It is actually a village area that is often mistaken to be a city (as in a capital or port city) of this south Pacific territory of the United States of America. Its 2000 population was 11,500. Pago_Pago
Norfolk, Virginia Norfolk is an independent city in the Commonwealth of Virginia in the United States. With a population of 234,403 as of the 2000 census, it is Virginia's second-largest incorporated city.Norfolk is located in the Hampton Roads region, named for the large natural harbor of the same name located at the mouth of Chesapeake Bay. Norfolk,_Virginia
Bering Sea The Bering Sea is a body of water in the Pacific Ocean that comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves.The Bering Sea is separated from the Gulf of Alaska by the Alaska Peninsula. Bering_Sea
Dust devil A dust devil is a strong, well-formed, and relatively long-lived whirlwind, ranging from small (half a meter wide and a few meters tall) to large (over 10 meters wide and over 1000 meters tall). The primary vertical motion is upward. Dust devils are usually harmless, but rare ones can grow large enough to threaten both people and property. Dust_devil
Louisville, Kentucky Louisville (usually ; see Pronunciation below) is Kentucky's largest city and county seat of Jefferson County. Since 2003, the city's borders are coterminous with those of the county due to merger. The city's estimated population as of 2007 is 709,264 (consolidated; balance total is 557,789), with a population of 1,233,735 in the Louisville metropolitan area. Louisville,_Kentucky
Fog Fog is a cloud bank that is in contact with the ground. A cloud may be considered partly fog; for example, the part of a cloud that is suspended in the air above the ground is not considered fog, whereas the part of the cloud that comes in contact with higher ground is considered fog. Fog is distinguished from mist only by its density, as expressed in the resulting decrease in visibility: Fog
Altitude Altitude has multiple uses depending on the context in which it is used (aviation, geometry, geographical survey, sport, and more). As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context.Vertical distance measurements in the "down" direction are commonly referred to as depth. Altitude
Potomac River The Potomac River flows into the Chesapeake Bay, located along the mid-Atlantic coast of the United States. The river is approximately 383 statute miles (665drainage area of about 14,700 square miles (38,000watershed, where precipitation provides the equivalent of over 8 m³ (more than 2,100 US gallons) of water per person per year. Potomac_River
Chesapeake Bay Chesapeake Bay is the largest estuary in the United States. It lies off the Atlantic Ocean, surrounded by Maryland and Virginia. The Chesapeake Bay's watershed covers in the District of Columbia and parts of six statesNew York, Pennsylvania, Delaware, Maryland, Virginia, and West Virginia. Chesapeake_Bay