Hydrographs

Length. The nautical mile is a special unit employed for marine and aerial navigation to express distances. The conventional value was adopted by the 1st International Extraordinary Hydrographic Conference, Monaco, 1929, under the name International nautical mile. 

J. Stevens, ed.. Hydrographic Data Books Lupoid and Stevens, Inc., Portland, Ore., 1969. 

Hydrograph An instrument that measures and records relative humidity. 

Fig. 6-6 Hydrograph showing the rapid contribution of surface runoff and more steady baseflow. Runoff in cubic feet per second, precipitaion in inches. (From Langbein and Wells, 1955.)...

Surface runoff. Hydrologists have identified two processes for generating surface runoff over land. The first, saturated overland flow (SOF), is generated when precipitation (or snowmelt) occurs over a saturated soil since water has nowhere to infiltrate, it then runs off over land. SOF typically occurs only in humid environments or where the water table rises to intersect with a stream. Horton overland flow (HOF or infiltration-limited overland flow) occurs when precipitation intensity exceeds the infiltration capacity of the soil in a non-saturated environment. In this case, only the excess precipitation (that exceeding the infiltration capacity) runs off over the surface. Both types of overland runoff generate relatively rapid flows that constitute the surface water contribution to the hydrograph (Fig. 6-6). 

Fig. 8-10 Erosion rate as a function of relief for (a) mid-latitude medium-sized drainage basins (modified from Ahnert, 1970), and (b) for Hydrographer s Volcano, Papua New Guinea (data source Ruxton and McDougall, 1967).

Williams, R. T. (1982). "Transient Tracers in the Ocean Preliminary Hydrographic Report," Vols 1-4. Scripps Institution of Oceanography, La Jolla, CA. 

It depends on local hydrographic conditions whether a playa is wet around the year or dries out. A playa may stay (almost) permanently wet if it is part of a closed basin that is under the influence of groundwater. Some playas such as the Dead Sea are fed by perennial rivers and will not dry out either but their water is so salty that salts precipitate. Laminated evaporates of considerable thickness can form in this way, with lamination reflecting the periodicity of the seasons. 

Again, as in the case of the surface film samplers, information on the comparative merits of the various water samplers is largely anecdotal. Although such studies are not inspiring and require an inordinate amount of time, both on the hydrographical wire and in the laboratory, they are as necessary for a proper interpretation of data as are intercalibration studies of the analytical... 

The Ebro River basin is located in the NE of the Iberian Peninsula, occupying a total surface of 85,362 Km2. Most of the watershed surface area is in Spanish territory, but small parts drain in Andorra and in France (445 km2 and 502 km2, respectively). The Ebro River is the largest hydrographic basin in Spain, accounting for 17.3% of its total surface area. 

Tardy Y, Bustillo V, Boeglin JL (2004) Geochemistry applied to the watershed survey hydrograph separation, erosion and soil dynamics. A case study the basin of the Niger River, Africa. Appl Geochem 19 469-518... 

Forch, C., M. Knudson, and S.P. Sorensen. 1902. Reports on the determination of the constants for compilation of hydrographic tables. Det Kongelige Danske videnskabernes selskabs skrifter. Naturvidenskabelig og mathematisk afdeling. 6.Raekke Vol 12(1) 1-151. 

Ross, A.A., L.I. Gordon, C.W. Mordy, J.C. Jennings, J. Johnson, and J. Wilson. 1999. Nutrient data differences between crossings of WOCE Hydrographic lines. Eos Trans-American Geophysical Union 80 (supplement), OS4. 

Global map of average mixed layer depths In (a) February and (b) August based on hydrographic data collected from 1941 through 2002. Source After de Boyer Montegut, C., ef al. (2004). Journal of Geophysical Research 109, Cl 2003. (See companion website for color version.)... 

Longitudinal profiles in the Atlantic Ocean at about 25°W. (a) Potential temperature (°C), (b) salinity, (o) potential density (0 dbar), (d) potential density (4000 dbar), and (e) dissolved oxygen ( j,mol/kg). Source-. After Talley, L. (1996). Atlantic Ocean Vertical Sections and datasets for selected lines. http /sam.ucsd.edu/vertical.sections/Atlantic.html. Scripps Institute of Oceanography, University of California - San Diego. Data are from WOCE hydrographic program. (See companion website for color version.)... 

Usually, several sampling bottles are deployed at one time so that multiple depths can be sampled during deployment of the hydrowire. A single deployment is called a hydrocast. It typically takes several hydrocasts to obtain enough samples to construct a detailed depth profile, especially in the deepwater columns of the open ocean. An example of a standard set of hydrographic profiles is shown in Figure 9.1. 

Hannah D, Smith B, Gumell A, McGregor G (2000) An approach to hydrograph classification. Hydrological Processes 14 317... 

Dpving, K. B., Westerberg, H., and Johnsen, P. B. (1985). Role of olfaction in the behavior and neuronal responses of Atlantic salmon, Salmo salar, to hydrographic stratification. Caradian Journal of Fisheries and Aquatic Science 42,1658-1667. 

During the strong spring tide series which coincided with the decline of the bloom, the vertical and horizontal advection indicated by cell counts and hydrographic data probably contributed significantly to the reduction in the population at stations near the head of the bay. A major wind event coupled with the strong tides may have driven a portion of the cells out of the bay. 

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