CHES BAY PHYSICS Flashcards
(29 cards)
estuary
semi-enclosed coastal body of water having a free connection with the open sea and within which the sea-water is measurably diluted with fresh water deriving from land drainage
features of estuaries
environmental conditions fluctuate
high biomass - productive
low species diversity
Advection
gravity flow downhill towards the mouth of Bay
Tidal forces
gravitational pull of moon and sun on lens of water on earth surface
Coriolis
gravitational deflection of water to the north east caused by spinning of the earth
Bay Circulatory System
- The heart/pump is advection, tides, and coriolis
- Transports oxygenated water made by plants to aerobic organisms
- Distributes nutrients
- Removes waste
when is the bay saltier
in the fall because less rain, so saltwater from ocean moves further up the bay
when is the bay least salty
in spring, there is increased runoff from rain and snowmelt (more freshwater flow)– pushes salt downstream
what determines the salt wedge position
tides
in high tide, salt moves up a lot
in low tide, salt moves up less+
Stratified estuary
Less dense fresh water flow towards the sea
More dense salt water intrusion towards land
opposing forces equal in volume and velocity
what inhibits mixing in a stratified estuary
pycnocline
Cold water is _____ than warm water
denser
Pycnocline
Rapid change in DENSITY (T, Salt) forms a physical barrier that prevents exchange of dissolved oxygen from surface to deeper waters
How long does it take to flush pollutants out of the bay
on average 1 year because of tide ebb and flow – cycle Very small net progress towards mouth on each tidal cycle
most important thing to cleaning up the bay
providing MORE OXYGEN
spring tide
max force you can pull water away from earth is when moon and sun are aligned
neap tide
when there is the least variation between high and low tides
diurnal
one low and one high in 24 hours
semidiurnal
two low tides and two high tides in 24 hours
THIS IS WHAT THE BAY HAS
flood tide
tide is going into the bay
high tide
water is at highest point
ebb tide
water being pulled back out of the bay
low tide
water at lowest point
slack tide
period right before tide is reversing (0 velocity – neither going up or going down)
slack before ebb is the slack before the water begins to flow back out to the ocean
