What Causes Tides? Essay Sample

Tides occur due to the combination of the effects gravity of the moon and sun gravity and the motion of the earth. The gravitational attraction between the earth and the moon holds them together with an equal and opposite centrifugal forces (Land Information New Zealand, n.d). Since the position of the moon changes as it orbits around the earth, the gravitational forces it applies to the earth changes leading to low and high tide. The same changes occur due to the revolution of the earth that changes the position of the earth relative to the position of the sun and the moon.
Explain how horns, cirques and arêtes form.
When two adjacent glaciers wear a steep ridge, a thin crest-like a rock called an arête forms. It is the edge formed between two adjacent glaciers due to continued backward erosion is called an arête. When two or more arêtes form adjacent to each other, a middle sharp-edged rock called a horn forms. A cirque is an amphitheatre-shaped basin formed at the head of the glacier valley. Glacier erosion cuts backwards leading to a depression that faces down the valley and has precipitous walls.

What is the Global (Atlantic) Conveyor Current? How does it affect Europe's climate

The conveyor belt is the thermohaline circulation of ocean water. The circulation involves the sinking of the water surface water that forces the cold water rich in nutrients to the surface. The conveyor belt starts on the surfaces of the North Atlantic Ocean (NOAA, 2013). At this section of the ocean, the water temperature is low, and there is a lot of salt concentration since the salt does not freeze. The water becomes denser than the surrounding water and tends to sink to the bottom of the oceans. As the denser water sink, surface water moves to replace it creating a current. It is this current that moves the warm surface water and the deep cold water in an endless circular movement called the conveyor belt. The conveyor belt is responsible for the stability of temperature in the Europe. In the event that global warming leads to an increase in the amount of rainfall, an increase in fresh warm water may stop the sinking of the water that would lead to temperature changes in Europe.

Work cited

Land Information New Zealand. “Gravitational forces & a tidal bulge.” N.p.. Accessed on April 16, 2015 from http://www.linz.govt.nz/sea/tides/introduction-tides/cause-and- nature-tides
NOAA. “The Global Conveyor Belt.” 2013. Accessed on April 16, 2015 from http://oceanservice.noaa.gov/education/kits/currents/06conveyor2.htm