Tides and Weather
What direction do low pressure systems rotate in the southern hemisphere?
Clockwise
What is the name of the driving factor for deep ocean currents?
Thermohaline circulation
The movement of sediment along the coast by constant wave action is known as ___________
Longshore drift
The total balance between sediment loss and gain on a beach is called _______________.
A sewage pipe running straight into the ocean would be an example of, point or non-point source pollution?
Point source pollution.
What does the distance between isobars indicate in terms of wind and pressure?
Wind speed and pressure gradient.
What causes deep ocean downwellings?
The freezing of surface water at the poles excreting salt into surrounding waters making it denser.
The bending of waves due to gradually shallowing water.
Refraction
Where would you locate a training wall.
Rivermouth
Global anthropogenic CO2 emissions causing ocean acidification would be an example of, point or non-point source pollution?
Non-point source pollution
How does tidal range differ between neap and spring tides?
Neap, Lower tidal range
Spring, Higher tidal range
Identify two factors that drive surface currents.
- Gravity
- Pressure
- Wind
- Coriolis effect
When waves diffract they can be seen to be ____________
Spreading.
Why are sand nourishment strategies introduced to beaches?
To widen/combat erosion of sand.
What environmental effects could agricultural runoff have on a marine ecosystem?
Eutrophication/algae blooms/hypoxia
During what phase of the moon would you expect tidal currents to have the strongest push/pull?
New and full moon.
Does an Ekman spiral move water more at the surface or at depths?
Surface.
I count 30 waves in 2 minutes, with a wavelength of 20m. What is the celerity?
C = 5 m/s
What is the purpose of a groyne?
Stop erosion/promote accretion
What are the potential effects of highly toxic materials such as heavy metals, PCBs (industrial chemicals) and DDT (pesticides) that persist in the environment?
Toxicity within marine systems due to bioaccumulation within the food chain.
If a weather map shows the following features, what wind weather and wave conditions would you expect to see?
Isobars spread far apart.
Offshore wind.
High pressure system.
Low wind.
Clean wave conditions.
Fine weather.
In terms of productivity, what would be expected to happen at an area of upwelling and why?
High productivity due to influx of nutrient dense water.
Constructive waves leading to a micro ridge and wide berm would be factors of what type of coastal process?
Accretion
What coastal engineering strategy would result in high amounts of wave reflection?
Seawall
What are the areas that must be considered in managing sustainability?
Environmental protection, social development and economic growth.