The moon and the Sun develop and height of inflow will be : At quadratures when the corner between the directions from Earth on the Moon and the Sun is close to direct (the first and last of the Moon), prilivoobrazuyushchy powers of the Moon and Sun and height of inflow will be the smallest.
By determination of initial parameters of waves their average values dismiss: heights of N, a To and the T period. For a of various port objects it is necessary to know heights of waves of a certain. Security wave parameter in system of waves is understood as the quantity of waves expressed as a percentage, at numerical value of a is more or equally, than at other waves among from 100 waves passing one by one through a point of the water area.
Wind. The wind mode is characterized by the direction, a, duration and repeatability. Knowledge the mode especially important at construction of ports at the seas and reservoirs. The direction and intensity of excitement which define configuration of external devices of port, their design and the direction of water approaches to port depend on a wind. The dominating direction of a wind has to be considered also at a relative positioning of moorings with different freights.
All phenomena occurring in the atmosphere belong to meteorological and climatic factors, and for a portostroyeniye winds, air temperatures and waters, rainfall and fogs have the greatest. The major hydrological — fluctuations of water levels, excitement, currents and the ice mode.
On the rivers the main reason causing rearrangement of coast is the current. To the majority of the flat rivers of a twisting meandrichesky form of the course. If the river, developing tortuosity, will approach the sites of the valley put by poorly washed away breeds, bends cease to and start slipping downstream, keeping the. If the stream is not constrained by valley slopes, bends turn into loops with well expressed. In cases when at high levels water is freely poured through a bend isthmus, even with its big width there can be a break of an isthmus to sharp change of the course.
The main reason for change of level on the free rivers seasonal change of a consumption of water though on the course of levels to have impact and natural rearrangements of the bed of the river and ice zazhor and jams. In the long-term period it is possible to notice essential influence of activity of people on levels. So, on some rivers where vypravitelny and dredging works were intensively carried out, the general decrease in water levels creating serious a in operation of earlier built moorings is noticed.
Island ports, apparently from the name, are located on islands and have no overland communication with the coast. They are created for transfer of freights from vessels of one type on others or for a of vessels which in view of big rainfall cannot approach of the main port.
Trade ports, from the greatest development fish ports, are equipped with warehouses refrigerators and in the structure the enterprises. Such, being bases fleet, have as, and own devices.
Water level fluctuations. This major hydrological defines not only elevation marks of the territory of port and depth on approaches and at moorings, but also a form of fastening of the coast and a design of berthing facilities. With amplitudes of fluctuations of level on the free rivers unprofitable application of vertical fastening of the coast also should be passed on less convenient in operation or poluotkosny.
The transport ports intended for transfer of freights and passengers from one type of transport on another can be on ports of general purpose in which the most various freights and change passengers, and special, intended for processing of any one freight (coal, ore, oil, the wood etc.). As a rule, ports have powerful high-performance devices which serve for processing of only one type of cargo.
Devices for an overload of other types of freights and moorings in special ports if exist, minor value. Quite often also special passenger ports in which cargo operations by a baggage overload meet.
Ports of world value are the centers of a world and accept the vessels floating by all seas and oceans. of the international value accept the vessels floating in of that pool on which the port is located. Ports of internal value, or coasting ports, serve internal transportations between ports of only one country.