Reading Notes: Oceans & Tides & Sea LEvel Rise Flashcards
What a Guyot?
Sea mountain with flat top
What did Oceans come on the scene?
3.5 Bya
How many chems in Sea Water
70 chemicals (#1 is chloride #2 is sodium ions)
HOw many tons of dissolved solids a year in ocean?
4 bill
Outgassing =
Earth releases gas from hydrothermal vents
What kind of equilibrium does seawater enjoy?
DYNAMIC equilibrium
What are conditions of dynamic equilibriuM?
Additions offset by losses
What atom / molecule is removed from sea water when it is blown into the wind?
Ions
What minerals are lost from sea water when it is blown around?
Salt and gypsum
When gypsum, salt, and ions are blown from the ocean and onto land, magnesium is formed, creating 2 possible things …
dolomite / clay, or calcium and silica for seashells
What’s a photic zone?
Ocean in the sun. Visible.
What’s an aphotic zone?
Deep ocean. Not visible.
Upwelling and downwelling – which one is more important and why?
upwelling brings minerals into the photic zone (nitrates / phosphates)
Pelagic clay is
ooze / sand / clay made of skeletons and shells (calcareous or siliceous)
3 types of reefs
fringe / barrier / atoll
Two types of tide:
High tide and ebb tide
OTEC stands for
Ocean Thermal Energy Conversion
They build a wave power plant in Scotland (2000-2018). How’d it go?
Not good. Too unpredictable.
Advanced design for getting energy from waves …
LIMPET
How’s a LIMPET work?
Trappped waves drive “piston” … Suction of outgoing also drive “piston” … And then turbine
The sun’s tide generating force is only ____% of the moon’s …
46%
It takes the moon ____ minutes longer each day to return to the same spot
50
What’s a “spring tide”
Sun & moon acting together on tides every 2 weeks
When moon @ 90 degrees from sun (also every 2 weeks) …
Moon tides cancel out solar tides.
What’s a NEAP tide?
When moon tide cancels out solar tide.
When moon tide cancels out solar tide, what percentage lower than usual?
20%
Celerity =
The speed a wave advances
The speed a wave advances =
Celerity
C = L / T
Celerity = Length x Time (Speed a wave advances)
Waves have greater “range” when …
Great drop offs.
What’s “fetch” mean in terms of wind blowing?
Fetch = when wind blows less on land than over water
Why freshwater no tides?
Fetch (more wind on ocean than over land)
Wave refraction in the near shore zone results in …
alignment of waves to coast
You’re stuck in a rip tide! Where do you swim?
Left or right. Never fight a rid tide.
Wave cut platform
sea cliff erosion makes hollows, then debris forms platforms …
A wave cut platform is sloped down towards the shore
no. it is sloped downwards into the sea.
What’s a berm?
Lump in a beach.
Two kinds of beaches…
Summer & Winter
Summer beaches have berms.
Yes.
Winter beaches have berms.
Small or none. Often under water.
Near-Shore Sediment Budget
Negative if more is taken away than added.
What maintains the Near-Shore Sediment Budget the most?
Rivers
Two kinds of COASTS
DEPOSITIONAL VS EROSIONAL
Depositional Coasts have these 3 things.
reefs, barriers, deltas
Erosional Coasts have 2 things …
Steep cliffs / not many islands.
South California is both Depositional and Erosional because …
It is emergent / up-lifted (depositional). But also erosional.
Opposite of an emergent coast …
Submergent coast (slowly submerging)
Marine Terrace =
bank / hill / where ocean used to meet the shore long ago. Like Davenport St. for Lake Iroquois.
NOAA stands for
National Oceanic and Atmospheric Administration
USGS stands for
United States Geo Survey
EPA stands for
Env Protection Agency
By how many millimeters has sea level been rising …
1.6 mm
How many CM has ocean risen since 1880
21-24 cm
Uplift means …
Land rising faster than sea.
Why ocean rising?
ice melt, thermal swell, mountain glacier water entering sea because blocked from lakes
EEZ
Exclusive Economic Zone - 332 KM from shoreline belong to that country
332 km
how much shoreline belongs to country under Exclusive Economic Zone (EEZ rule)
