Coasts topography

The topography of Mt. Desert Island c. the irregularity of the Maine coast. 

Glacial modification of topography in the Coast Mountains, British Columbia. Few... 

In the bottom topography of the sea, one can clearly distinguish three principal structures the shelf, the continental slope, and the deep-water basin. The shelf occupies up to 25% of the total area of the seafloor and, on average, is restricted to sea depths of 100-200 m. It reaches its greatest width (more than 200 km) in the northwestern part of the sea, which is entirely located within the shelf zone. Almost over the entire extension of the eastern and southern coasts of the sea, the shelf is very narrow (only a few kilometers wide) in the western part of the sea, it is wider (a few tens of kilometers). 

Abstract This chapter is devoted to a description of the present-day bottom topography and types of coasts of the Black Sea, as well as to the general character of the bottom sediments. Two maps of topography and sediments illustrate the morphology of the Black Sea basin and the particular features of the evolution of its coasts. 

In this chapter, we present a description of the present-day topography of the floor and the coasts of the Black Sea and of the distribution of the bottom sediments over its floor surface. 

With respect to the features of the topography, the northern coast of the sea significantly differs from the eastern and southern coasts. Its particular features include the generally plain character (except for the Crimean Mountains) and the presence of estuaries of the major rivers of the Black Sea basin. 

The eastern and southern coasts are mountainous. The coastal ridges of the folded structures of the Caucasus and Anatolia extend parallel to the coastline, forming a longitudinal type of mountainous topography. At places, the slopes of the mountains descend directly into the sea in the form of steep escarpments. In the southeastern part of the Black Sea, within the Kolkhida lowland, mostly accumulative coasts are developed. 

Fig. 1 Topography of the coasts and floor of the Black Sea. Bottom relief 1 shelf a accumulative, b abrasive 2 continental slope a accumulative, b stepwise 3 floor of the basin 4 continental footstep 5 underwater canyons 6 bars a sandy, b marginal 7 morphological boundaries a distinct, b fuzzy. Coast types 1 landslide 2 abrasive 3 abrasive-accumulative 4 accumulative 5 lagoonal 6 deltaic...

Atmospheric precipitation. Atmospheric precipitation over the Black Sea is mostly related to the cyclonic activity. The convective process plays a noticeable role only it near-shore band and on the coasts. An additional influence is provided by the topography of the coastal zone. Throughout the year, the precipitation amount grows from the northwest (380-420 mm/ year) to the southeast, where the Caucasian ridges approach the coastline and are oriented across the principal moisture-bearing airflows (up to 1500-2500 mm/year) (Fig. 8). The greatest number of days with precipita-... 

The eddies were formed off the eastern coast of the Black Sea and moved westward showing a decrease in the phase velocity in the narrowest area of the sea south of the Crimea. In the model version with a flat abyssal floor at a depth of 1540 m, the wavelength comprised 250 km in the east and 190 km in the west with a period of 160 days and a phase velocity of - 2.0-2.5kmday-1. The orbital velocities in the eddies in the surface layer reached 0.45 ms 1 and deeper decreased down to 0.25 ms-1 a depth of 70m and to 0.05 - 0.10 m s 1 at a depth of 1100 m. The wave regime was more intensive in the eastern part of the Black Sea in its western part, eddies dissipated above the continental slope and partially reflected from the western coast. In the study [50], the introduction of the abyssal bottom topography increased (reduced) the sizes and intensities of cyclonic (anticyclonic) eddies by a factor of 1.5-2. The cyclonic (anticyclonic) eddies became more alike the SBCGs (NSAEs) in Fig. 1. The period of the eddies grew up to almost two years, while their phase velocity decreased down to 0.4-0.5 km day-1. 

Figur 33 1 Physical and biological upwelling response simulated by the Wroblewski (1977) 2-dimensional coastal upwelling model (A) The circulation in the transverse plane normal to the coast, the bottom topography, and the wind stress. The maximum u and w velocities in the field are —2.9 cm s and 1.4 x 10 cm s , respectively. (B) The daily gross primary production of the water column. (C) The distribution of phytoplankton. Contour intervals are 1 jimol N 1. Redrawn with permission from Wroblewski (1977).

The results of the computation, such as the wind field, concentration and dose distribution, are stored in the magnetic disc and are displayed on the graphic display together with some map elements. The user can select several kinds of map elements, such as administrative boundaries, coast lines, road/railroad, topography and locations of towns. The system can display the following information ... 

Yagi is located on the northern coast of the Oshima Peninsula in southeastern Hokkaido. The site is located on a broad terrace that rises steeply 40 m above a narrow coastal strip. It is backed by a series of low, wooded mountains about 100 m in elevation and is circumscribed by two small rivers. Much of the terrain is very rugged. Most of the peninsula is andesitic highland, and its topography and geology are heavily influenced by local volcanic activity. The Oshima peninsula has two active volcanoes, Komagatake and Essan both are within 30 km of the site. 

The corresponding boundary conditions are no mass flux through the coast and a bounded stream function far offshore. Equation (2.38) forms together with the boundary conditions an eigenvalue problem that can be solved analytically only for a special analytical form of the shelf topography and must be solved numerically for naturally shaped shelf topography. 

In the Baltic Sea, the offshore scale for the transition of topography from the coast to the plain areas of the basins is commonly much larger than the baroclinic Rossby radius. Therefore, CTW can be used to analyze the dispersion and modal structure of sea level variations and quasi-geostrophic currents trapped at the basin rim. Some basins do not have well established plains, therefore, in these basins, the eigenvalue problem must be solved for the whole basin diameter, for example, the Eastern Gotland Basin. The CTW structures of both coasts splice each other in the center of the basin. Hence, CTWs are an effective mechanism for the communication between the rim and the center of the corresponding (e.g., Gotland) basin. 

Data from the shallow inshore sites off Hiddensee (WKl and WK2 at 6 and 7 m depth) also exhibit a directional stability of about 50%. Here, in the narrow Gellenstrom area close to the western coast off Hiddensee, surface waves possibly affect the alongshore flow in addition to wind and topography. 

Fig. 5 Coastal and bottom topography of the Aral Sea (according to [2, 24, 25]). Types of coasts (1) abrasion-denudation coasts (2) abrasion coasts with slumps (3) graded abrasion coasts (4) embayed coasts with accumulative landforms (5) graded complex coasts (6) embayed ingression coasts (7) graded accumulative coasts (8) deltaic coasts (9) reed coasts (10) nearshore shallow (0-20 m) (11) central depression (20 0 m) (12) central deep (40-68 m) (13) submarine ridge (ArkhangeTskii Ridge)...

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