Global Climate

Question 1

Weather

Answer 1

Weather is a snapshot of day-to-day changes in factors such as temperature, rain and wind.

Question 2

Climate

Answer 2

Climate is concerned with longer periods of time and involves the collection and analysis of data over decades.

Question 3

Factors affecting climate

Answer 3

Energy Absorption
Ocean currents

Question 4

Earth Orbit

Answer 4

The orbit of the earth is not circular but elliptical.
This means at some time of the year the Earth will be closer to the Sun.
At other times, the Earth will be farther from the Sun.
This varies the radiation in the atmosphere by 3.5% a year.

Question 5

Spherical shape of the Earth

Answer 5

The equator has a consistently warmer climate than the poles of the Earth.

Radiation from the Sun that reaches Earth has the same energy, whether it hits the Earth near the poles or at the Equator.

At the poles, the energy isspread over a larger area and at the equator, the energy is concentrated in a smaller area.

Question 6

Albedo Effect

Answer 6

Light is reflected differently by different surfaces.
The difference in reflective properties of surfaces is called the albedo effect.
It is measured as a number from 0 to 1;
0 = A very black surface (reflects no light)
1 = A very white surface (reflects a lot of light)

Ice and snow reflect up to 90% of sunlight, 45% for sandy deserts, 20% for green fields, 8% for brown earth and 3.5% for oceans.
A reduced number of white surfaces (ice and snow) results in the Earth absorbing more heat and therefore, higher temperatures.

Question 7

Ocean Currents

Answer 7

The movement of water in the oceans distributes the heat absorbed from the Sun.
Water in the ocean differs in its salinity (salt concentration) and temperature, depending on the location.
These differences cause deep ocean currents, which are known as the thermohaline circulation. At the poles, water gets cold forming sea ice.
When the water freezes, salt is left behind, causing the seawater to become saltier.
As the seawater gets saltier, it also gets denser and starts to sink.
Warm surface water is pulled in to replace the sinking water.
This eventually becomes cold and salty enough to sink, starting the the deep-ocean currents.

Question 8

Coriolis Effect

Answer 8

The Coriolis effect is the influence of the Earth’s rotation on the direction of air or water movement.
The rotation of the Earth causes wind and water to deviate from the path you would expect them to take.
The Coriolis effect occurs due to different parts of the Earth moving at different speeds and differences in air pressure.