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Flashcards in Tides Deck (15):
1

What defines spring tides?

1. highest high tides and lowest low tides in this cycle:
2. sun and moon line up to create stronger pull

2

What defines neap tides

1. lowest high tide and highest low tide
2. sun and moon do not line up their gravitational pulls

3

Three types of tides

Semi-dinurnal tides
mixed tides
diurnal tides

4

Define semi-diurnal tides

2 highs and lows per day

5

Define diurnal tides

1 high and one low per day

6

Define mixed tides

semi-diurnal signal modulated by diurnal signal

7

Tidal bore: define.

a steep-fronted wave that moves up rivers as the tide increases

8

Define tidal currents

The horizontal motion of water during tides. It flows in and out!

9

what are two driving forces of oceans

Wind and drag created at the ocean surface
Differences in density between water masses

10

What is the primary driver of surface currents?

Wind

11

What is the primary driver of deep water currents?

density

12

What is the factor that drives all sorts of currents?

the transfer of heat from tropics to the poles.

13

Define ekman spiral

coriolis force applied to wind-driven surface currents

14

what causes el nino?

reductionor reversal of southeast trade winds from decrease differences between high and low pressure zones

15

consequences of el ninos (5)

1. cooler upwelling waters forced downward
2. Thermal expansion of water increases water level
3. Bleaching
4. decrease of upwelling nutrient rich water from bottom