MeteorologyAtmospheric Temperature :
The annual average temperature is 12.3 C;
The annual highest average temperature is 16.2 C;
The annual lowest average temperature is 9.1 C;
The extremely high temperature was 39.9 C (24th July,1955)
The extremely low temperature was – 18.3 C (17th Janury,1953)
The annual average precipitation is 586.0mm;
The annual biggest precipitation was 1083.5mm (1964)
The smallest precipitatiom was 278.4mm (1968)
The daily biggest precipitation was 191.5mm (30th July,1975)
The wind direction in this district is conventionally E. The frequency is 11.7%.The second place is the S direction at a frequency of 10.34%. The strong wind is usually in E direction at a frequency of 1.96% is at 6 degree and over . Annually the wind-force of 6 degree and
over is at a frequency of 3.65% for all directions.
At the average of 27.5 days annually are with thunderstom, normally in June and July.
The visibility of less than 1 km is with the average of years is 16.5 foggy days ,normally occurs in the autom and winter and with the Sun rises,the fog disapears soon . According to the statistics, the visibility of less than 1 km actually is of 5 .0 days annually.
The average relative huminity 65%
The biggest relative huminity 100%
The smallest relative huminity 3%
The tide in this area is of irregular half-day type. Its (HO1+HK1)/HM2=0.53.
The relation-ship between the dadum planes:
The relation-ship between the local theoretically lowest tide and the Dagu zero point and the local average sea level as the following graph:
The local average sea level
The Dagu zero point
Data of the tide feature:
The local theoretically lowest tide level
Annually highest tide point 5.81m? (1st September,1992)
Designed water level:
Annually lowest tide point - 1.03m (10th November,1968)
Remarks:There was a lowest tide point of -1.08m in 18th December,1957.
Annual average high tide poit 3.74m
Annual average low tide point 1.34m
Annual average sea level 2.56m
Annually greatest tide difference 4.37m? (October 1980)
Annual average tide difference 2.40m
The designed highest water level 4.30m
The designed lowest water level 0.50m
The extremely high water level 5.88m
The extremely low water level - 1.29m
The port is under the protection of the North Great Breakwater and the wave influnce is out of consideration.
The curent in the port water area is of back-and-forth mode. The current direction in the port parallels the port channel axis and the speed is faster when the tide rises.
In winter the port water area ices to some extent. The icing begins in the last ten days of December and ends in the last ten days of february within a period of 60 days. According to the statistics of years,the annual heavy icing time is of 10 days at average. Normally the ocean ice doesn’t much affect the port operation and shipps sailling.
Since the Tianjin Port has been built,the circling silt deposit in the port has always been focused by the common. Through researching and construction in tens of years, the slugde-reducing project has reached to a good result. The ratio of annual out-put and sludge excavation (cbm/out-put ton) in the 90s has come down to 0.08-0.09 which is lower than the Port of rotterdam in Holland whose ratio in the 80s was 0.115.
The fresh researches have proved that the Tianjin Port belongs to the kinds of slight-circling-silt port. The circling-silting-up question is no-longer an element affecting the development of the port. Oppositely, the millions of cubic metres of silt annually have become the important resources in the land extending at the port. It’s surely expected that along with the improvement to the conditions on port silting-up and the adoptions of workable measures to harness the silting, the port silt deposit situation will turn better.
The exploration shows that the soil layers are distributed regularly in the area of Tianjin Port and maily lay in three sections from the top to bottom. The first is the artificial alluviation by the dredgings. The second layer is the marine deposit and silt clay mixed with shells.The third layer is from the Haihe River mouth delta deposit consisting of soil powder,clay powder, soil powder with fine sand and powder clay or powder soil mixed with fine sand.
According to the State Construction Design on Anti-seism Standards (GB50011-2001, the location ot the Port Project designed to endure the earthquake intensity up to 7 magnitude. The designed basic ratio on seism plus velocity is 0.15g..