eq2 Flashcards
hurricanes
tropical storms found in the Atlantic Ocean
cyclones
tropical storms found in the Indian Ocean
typhoons
tropical storms found in the Pacific Ocean
tropical storms
storm event that has very low atmospheric pressure
- leads to evaporation
- air rising
- cooling and condensing
- cumulunimbus clouds
- precipitation
wave formation
- wind blows across surface of ocean/lake
- friction
- water particles move in orbital motion, though not forward = oscillation waves
- wave energy moves in a column (up to down in circles)
- energy is passed forward
- as wave travels across, bottom drags along ocean floor
- creates friction
- upper part moves faster than rest as depth decreases
- upper part tilts forward as the dragging becomes stronger
- makes wave break in the surf zone
factors that affect strength of a wave
- wave height
- fetch
- wave refraction
- depth (affects height)
- wind speed
- hydro-meterological events
examples of fetch
- atlantic large
- mediterranean small
examples of wave refraction
- st David’s head
- st Ann’s head
- st Bride’s bay
characteristics of constructive waves
- low-surging waves
- long wavelength
- strong swash, weak backswash
- beach gain (constructive)
- low flat wave height
- strong swash pushes sediment up the beach
- weak backswash leads to deposition of sediment at the top of the beach
- 6/10 minutes
- gentle gradient
characteristics of destructive waves
- high energy waves
- short wavelength
- weak swash, strong backswash
- beach loss (destructive)
- high wave height
strong backswash erodes material - 11/15 minutes
- steep waves
Hydro-meterological events
tropical storms, flooding, extreme weather
berm
created especially in macro tidal areas such as Cornwall in Atlantic
erosional processes; abrasion
- as waves advance, pick up sand and pebbles from seabed.
- then, break at base of cliff. transported material is hurled at the cliff foot- chips away rock
erosional processes; hydraulic action
- when wave advances, air is trapped + compressed
- when retreats, compressed air expands again
- continuos process weakens joints and cracks in cliff
- force of rock can also hammer a rock surface.
- at high velocities, bubbles form in water + collapse, they erode by hammer-like pressure effects.
erosional processes; corrosion
- when cliffs are formed made by alkaline rock (chalk or limestone), or alkaline cement that bonds the rock particles together, solution containing weak acids in seawater can dissolve them