Geology topics

Stephen Jones

Publications and source records attributed to Stephen Jones.

3 recordsLinked to original sources

USGS2016

A multi-decade record of high-quality fCO2 data in version 3 of the Surface Ocean CO2 Atlas (SOCAT)

The Surface Ocean CO 2 Atlas (SOCAT) is a synthesis of quality-controlled f CO 2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.7 million f CO 2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.6 million f CO 2 values relative to version 2 and extends the record from 2011 to 2014. Version 3 also significantly increases the data availability for 2005 to 2013. SOCAT has an average of approximately 1.2 million surface water f CO 2 values per year for the years 2006 to 2012. Quality and documentation of the data has improved. A new feature is the data set quality control (QC) flag of E for data from alternative sensors and platforms. The accuracy of surface water f CO 2 has been defined for all data set QC flags. Automated range checking has been carried out for all data sets during their upload into SOCAT. The upgrade of the interactive Data Set Viewer (previously known as the Cruise Data Viewer) allows better interrogation of the SOCAT data collection and rapid creation of high-quality figures for scientific presentations. Automated data upload has been launched for version 4 and will enable more frequent SOCAT releases in the future. High-profile scientific applications of SOCAT include quantification of the ocean sink for atmospheric carbon dioxide and its long-term variation, detection of ocean acidification, as well as evaluation of coupled-climate and ocean-only biogeochemical models. Users of SOCAT data products are urged to acknowledge the contribution of data providers, as stated in the SOCAT Fair Data Use Statement. This ESSD (Earth System Science Data) “living data” publication documents the methods and data sets used for the assembly of this new version of the SOCAT data collection and compares these with those used for earlier versions of the data collection (Pfeil et al., 2013; Sabine et al., 2013; Bakker et al., 2014).

Earth System Science Data↗

USGS2013

Statewide summary for Alabama

Alabama is over 132,000 km 2 (51,000 miles 2 ) in area, 483 km (300 miles) long, and 322 km (200 miles) wide (Copeland, 1968). Coastal Alabama comprises Mobile and Baldwin Counties and the surrounding State waters in the Gulf of Mexico (Figure 1; O’Neil and Mettee, 1982). It is part of both the East Gulf Coastal Plain section of the Coastal Plain province and the Mississippi-Alabama shelf section of the Continental Shelf province. Within the East Gulf Coastal Plain section, Alabama’s coastal land falls within the Southern Pine Hills and Coastal Lowlands subdivisions. The Southern Pine Hills subdivision is a sloping landscape composed of sand and clay. Its elevation varies from approximately 30 m (98 ft) near the coast to over 90 m (295 ft) in the northern areas of the two coastal counties. The Coastal Lowlands subdivision is a flat to slightly undulating plain with creeks, rivers, estuaries, and marshes leading to the surrounding bays and the Gulf of Mexico. Offshore Alabama is part of the Mississippi-Alabama section of the Continental Shelf. Barrier islands and spits in coastal Alabama include Dauphin Island, Fort Morgan Peninsula, and Perdido Key. Dauphin Island consists of a beach with dunes on the Gulf side and beaches and marshes on the north side. It was once over 24 km long, but after Hurricane Katrina it has been broken into two distinct islands. Fort Morgan Peninsula is attached to the eastern mainland and extends westward between Mobile Bay and the Gulf of Mexico. A large beach exists on the gulf side, with numerous lagoons and marshes on the bayside. Perdido Key is a narrow peninsula on the easternmost Alabama coast near the Alabama-Florida border, south of Perdido Bay. It consists of beaches and high dunes, with some marshes on the lagoon side of the peninsula. Mobile Bay, parts of Mississippi Sound, Perdido Bay, and many smaller rivers and streams are the main bodies of water in coastal Alabama. Mobile Bay, a submerged river valley, is the largest at 1,070 km 2 (413 miles 2 ) in area and 51.5 km (32 miles) in length (Mobile Bay NEP, 2008). Mobile Bay is 37 km (23 miles) wide at its maximum width near the opening to the Gulf of Mexico at the south end of the bay, and 16.1 km (10 miles) wide at the city of Mobile (Mobile Bay NEP, 2003; Mobile Bay NEP, 2008). It is remarkably shallow with an average depth of 3 m (10 ft), yet it discharges approximately 1,755.6 m 3 (62,000 ft 3 ) of water every second on average (Mobile Bay NEP, 2008). Mississippi Sound runs parallel to the coasts of Mississippi and part of Alabama. The length of the Alabama portion of Mississippi Sound is approximately 26 km (16.2 miles) from the Dauphin Island bridge to the Mississippi-Alabama State line (O’Neil and Mettee, 1982). Dauphin Island separates the sound from the Gulf of Mexico. The sound drains into the Gulf of Mexico west of Dauphin Island at Petit Bois Pass, which is approximately 8 km (5 miles) wide. Mississippi Sound averages approximately 3.5 m (11.5 ft) in depth. Salt marshes, large areas of wetland scrub-shrub, and tidal creeks characterize the northern shore of Mississippi Sound, and the southern shore is composed of sandy barrier islands. Perdido Bay is located at the boundary of Baldwin County and Florida’s Escambia County. It is approximately 27 km (16.8 miles) long, 5 km (3 miles) at its widest point, and, on average, 2.4 m (7.9 ft) deep. The major fresh-water resource in coastal Alabama is the Mobile River, formed by the confluence of the Alabama and Tombigbee Rivers. The watershed for the Mobile River is approximately 111,369 km 2 (43,000 miles 2 ) large and includes parts of Alabama, Georgia, Mississippi, and Tennessee (Handley et al., 2007). Parts of Alabama and the Florida Panhandle drain into the Perdido River basin and western coastal Alabama drains into the Escatawpa River. Emergent wetlands offer valuable ecological services in coastal Alabama. Marshes provide extensive plant material, which provides energy to the detritus-based estuarine ecological system (O’Neil et al., 1983). They provide habitat for many organisms, including shrimp and crabs, whose harvest is a major industry in coastal Alabama. Marshes provide habitat for refuge, feeding, breeding, and spawning. They also remove excess nutrients from water and contribute to erosion control. Degradation of marshes by pollutants, sediments, and other impacts decreases productivity of the entire estuarine ecosystem. Among the nation’s states, Alabama ranks fifth in number of different species (144 endemic species), second in number of extinctions that have already occurred (90 extinct species) and fourth in number of species at risk for extinction (14.8% at risk out of 4,533 total species; Stein, 2002). Many species of wildlife benefit from the wetland habitats in coastal Alabama. Numerous bird species can be found in coastal Alabama emergent marshes, which provide habitat for shore- and wading-birds that inhabit salt or brackish water coastal environments (Anderson et al., 1981). Colonial seabirds nest on coastal Alabama’s islands, the mainland, and dredge disposal sites (Cooley, 1987). The Mobile-Tensaw Delta and Mobile Bay are the state’s primary migratory waterfowl coastal wintering areas (U.S. Fish and Wildlife Service, 1982). The shallow waters, abundance of fish, and vegetative cover in emergent marsh contribute to excellent waterfowl habitat. Emergent wetlands in Alabama also provide habitat for a multitude of endangered species, including various species of raptors and wading- and shorebirds (O’Neil et al., 1983).

Alabama↗

USGS2013

Mobile Bay

Mobile Bay is the largest bay found in Alabama’s coastal area (Handley et al., 2007). It was named an Estuary of National Significance in 1995 under the U.S. Environmental Protection Agency’s (EPA) National Estuary Program (NEP), and its Comprehensive Conservation Management Plan was completed in 2002. Mobile Bay is 1,070 km 2 (413 miles 2 ) in area and 51 km (32 miles) long, making it the sixth largest estuary in the continental United States (Mobile Bay NEP, 2008). Its ecosystem provides habitat for more than 300 species of birds, 310 species of fish, 68 species of reptiles, 57 species of mammals, 40 species of amphibians, and 15 species of shrimp (Mobile Bay NEP, 1997). Mobile Bay lies between the Mississippi and Atlantic Flyways (Mobile Bay NEP, 2003). Commercial and residential development and industrial use is heavy in the Mobile Bay area. Although local growth and industrial markets support the Mobile Bay area economy, the resulting environmental damage to the very ecosystem upon which they depend remains a threat to the environment, economy, and population. The Mobile Bay ecosystem boasts high biological diversity and productivity and supports many freshwater and saltwater species of recreational and commercial importance. The great diversity of Mobile Bay reflects the diversity of Alabama, which is home to the largest number of different plant and animal species of all states east of the Mississippi River (Stein, 2002), and is bolstered by the unique climate and geographic conditions surrounding the bay. Freshwater inflow from the Mobile-Tensaw River Delta, ranging from 60,000 to 3,700,000 gallons per second (Wallace, 1996), mixes with saltwater from the Gulf of Mexico, which enters Mobile Bay via wind and tides (Burgan and Engle, 2006). Because of the unique conditions surrounding Mobile Bay, including shallow waters, a dynamic climate, and artificial hydrologic modifications—such as the construction of the Mobile Bay Causeway in the 1920s, which serves as an unintentional barrier between Delta waters north of the Causeway and saline waters south of the Causeway, the salinity of Mobile Bay is highly variable. Mobile Bay receives an average of 165 cm (65 inches) of rain per year from tropical storms, summer thunderstorms, and winter cold fronts (Stout et al., 1998). The climate and geography that have made Mobile Bay so rich in resources have also contributed to the threats surrounding its ecosystem. The extensive amount of rain in Mobile Bay creates large amounts of runoff, polluting the waters with fertilizers, chemicals, sediment, oil, trash, and sewage (Mobile Bay NEP, 1997). Tourism, ecotourism, recreational and commercial fishing, recreational boating, shipping, and chemical, pulp, and paper production are significant industries in Mobile Bay and the surrounding areas. Despite the approximate \$3 billion and 55,000 jobs these industries bring into the community (Alabama Tourism Department, 2010), the growth, development, and environmental stress they create are major threats to the Mobile Bay ecosystem. Among the nation’s states, Alabama ranks fifth in number of different species (144 endemic species), second in number of extinctions that have already occurred (90 extinct species) and fourth in number of species at risk for extinction (14.8% at risk out of 4,533 total species; Stein, 2002). Twenty-one of these threatened and endangered species are found in Mobile Bay, whose brackish waters provide a nursery area for many species of vertebrates and invertebrates. Some of these species include the Alabama sturgeon, Gulf sturgeon, heavy pigtoe mussel, inflated heel-splitter mussel, West Indian manatee, Alabama beach mouse, Perdido beach mouse, Alabama red-bellied turtle, gopher tortoise, Kemp’s ridley sea turtle, green sea turtle, loggerhead sea turtle, eastern indigo snake, flatwoods salamander, piping plover, red-cockaded woodpecker, and wood stork. Habitat loss underlies the decline of some bird species in Mobile Bay, and large mammals such as the red wolf, Florida panther, and Florida black bear are no longer found in the area. However, some rare species, such as the swallow-tailed kite, sandhill crane, and gopher tortoise can still be found (Duke and Kruczynski, 1992). The value of wetlands in Mobile Bay and the rest of the Gulf of Mexico is still being investigated. Although various monetary valuations of wetlands exist, critics remark that undervaluation of wetlands is inevitable (Mobile Bay NEP, 2008) and that estimates often do not place appropriate value on ecological services (Mitsch and Gosselink, 2000). Additionally, many estimates account only for anthropogenic values. One estimate concludes that one acre of wetlands performs \$3,000 worth of water purification each year (Mobile Bay NEP, 1997). With more than 76,890 hectares (190,000 acres) of wetlands in the Mobile Bay area, that equates to a value exceeding one-half billion dollars every year. Tourism, fishing, boating, production, and shipping are significant industries in the Mobile Bay area. More than 90% of fish landed in recreational and commercial fishing in the bay depend on bay habitat, including wetlands, for life requirements (Mobile Bay NEP, 1997). The Port of Mobile is Alabama’s only ocean-ship port (Mobile Bay NEP, 2008). Baldwin County, on the eastern side of the bay, experienced a population increase of 75% from 1990 to 2007, with an 89% increase in housing units (Mobile Bay NEP, 2008). Development and industry support the Mobile Bay economy, but they depend on the continued health, sustainability, and production of the water and living resources of the Mobile Bay ecosystem. Wetland loss, along with other forms of environmental degradation, remains a threat to the Mobile Bay ecosystem and Mobile Bay’s socioeconomic foundation.

Alabama↗