Weather and Climate

Question 1

Isotherms

Answer 1

Lines joining place of equal temperature

Question 2

Isobars

Answer 2

Lines joining areas of equal atmospheric pressure

Question 3

Isohyets

Answer 3

Lines joining areas of equal rainfall

Question 4

Isohels

Answer 4

Lines joining areas of equal sunshine

Question 5

Humidity

Answer 5

This refers to the water content in the atmosphere

Question 6

Relative Humidity

Answer 6

This is the extent to which the air is saturated

Question 7

Daily Temperature Range

Answer 7

This is the difference between the highest and lowest temperature over a 24 hour period

Question 8

Mean Monthly Temperature

Answer 8

This is the average temperature for a month

Question 9

Weather

Answer 9

Weather is the condition of the atmosphere over a short period of time, usually on a daily basis.

Question 10

Climate

Answer 10

Climate is the overall state of the atmosphere over a prolonged period of time

Question 11

State 7 things that influence temperature/ climate

Answer 11

Latitude, Altitude, Aspect, Distance from the sea, Cloud Cover, Equatorial Regions, Desert regions

Question 12

How does Latitude affect temperature.

Answer 12

Since the Earth bulges towards the centre, the sun’s rays are more focused at the equator than the poles and causes it to be hotter. Additionally, there is less atmosphere at the equator than the poles and because of this, more of the sun ray’s is allowed to reach the equator.

Question 13

How does altitude affect temperature?

Answer 13

This is the height above sea level. The higher one goes above sea level, the cooler it becomes. for every 1000 metres above sea level, 6.5 degrees are lost. The sun’s rays first heat the surface and then the air above it. Therefore heat is lost as you move further away from the surface. Additionally, as you rise, there are less impurities such as smoke and dust which can trap heat. The heat is allowed to escape back into the atmosphere causing hgiher altitude to be cooler.

Question 14

How does aspect affect climate?

Answer 14

In the northern hemisphere, the south facing slopes are warmer than the north facing ones because they receive a greater amount of the sun’s heat and for a longer period of time during the year. The opposite occurs in the southern hemisphere. This is very noticeable in temperature latitudes which experience seasonal changes.

Question 15

How does distance from the sea affect temperature and climate?

Answer 15

Regions that experience climatic changes will be affected by this factor. During the summer months the ocean heats up slower than the land and the winds blow over the sea bring a cooling affect to the coastal areas. However, as the winds continue inland they become warmer due to heat from the earth. the reverse happens during the winter months

Question 16

How does cloud cover affect temperature?

Answer 16

The amount of cloud cover during the day or night will influence the daily temperature range. This is more clearly seen in equatorial and desert regions. It affects the amount of radiation(heat) reaching and leaving the earth

Question 17

How do equatorial regions affect temperature?

Answer 17

In equatorial regions, the presence of clouds reduce the amount of incoming radiation. At night. the clouds prevent the heat from escaping back into the atmosphere. As a result, the difference in temperature during the day and night is very small.

Question 18

How do desert regions affect temperature?

Answer 18

In hot deserts, the cloudless skies allow for rapid heating during the day and rapid heat loss at night since there is no blanket of clouds to trap the heat. Therefore desert regions experience a large difference in day and night temperature.

Question 19

What are the types of of rainfall?

Answer 19

Relief/Orographic rainfall , Conventional rainfall and frontal/cyclonic rainfall

Question 20

What is relief/orographic rainfall?

Answer 20

As the wind makes it’s way across the sea, the air absorbs water vapour by the process of evaporation. On reaching land, the air will be forced to rise if it ecounters a barrier such as a mountain. As it rises it cools and condenses. Clouds form and precipitation occurs(windward side). The drier air descends. As the air descends, it warms, meaning it can carry moisture, so there is little to no rain on this side of the mountain. (Leeward side or rain shadow)

Question 21

What is convectional rainfall?

Answer 21

During the day, the sun beats down on the surface of the ground. It becomes very hot, heating the air that is found directly above it. The hot air expands, becomes lighter and rises. As it rises, the air gets cooler. Further cooling causes condensation, producing large dark cumulonibus clouds and the rainfalls. These heavy showers often occur in the faternoom

Question 22

What is frontal/cyclonic rainfall?

Answer 22

This type of rainfall occurs where two large air masses meet. They are usually of very different temperatures. The warm air is undercut by the cold air, causing it to rise. Condensation later causes the formation of clouds and rainfall occurs.

Question 23

What is the ITCZ?

Answer 23

It’s the Inter-Tropical Convergence Zone. Where the north-east trade winds and south east trade winds meet, atmospheric conditions are unstable and force each other to rise, providing conditions which are favourable to rainfall. The ITCZ can be found by a belt of clouds with unsettled cloudy conditions. it is not stationary but moves north and south of the equator 10 degrees each direction. The angle that the two air masses meet will determine the amount of rainfall. The wider the angle, the greater the amount of rainfall

Question 24

What is an anticyclone?

Answer 24

These are high pressure systems which rotate in a clockwise direction in the northern hemisphere. Due to the high pressure centre, the air cannot rise and as a result, fair weather conditions prevail. They are usually slow moving can cause other weather systems to divert from their original path

Question 25

What is a cold front?

Answer 25

A cold front is a zone between the advancing wedge of cold air which undercuts warmer air, forcing it to rise. On either side of the cold front. there is a large difference in temperature. In the Caribbean cold fronts occur as cold air called “Northers” leave the continent of North America during the winter, travelling southward towards the caribbean. On meeting the warm air, it forces it to rise, thus causing rain to fall.

Question 26

What happens when a cold front occurs?

Answer 26

1. The temperature drops
2. The wind will become stronger
3. The wind changes direction
4. An increase in the amount of cloud cover
5. Heavy showers along the front on either side

Question 27

What is an easterly wave?

Answer 27

An easterly wave or tropical wave is a trough of low pressure which is usually formed off the coast of West Africa. It is also among the most important rain producing factors in the Caribbean and can develop into a hurricane. The winds tend to be moderate with heavy and continuous rainfall. The sky is usually overcast

Question 28

What is a hurricane?

Answer 28

A hurricane is a large spiraling mass of air with a low pressure centre known as the eye. The minimum wind speed is 75mph, with winds blowing in an anticlockwise direction. The eye is an area of calm, with clear skies and little or no wind. Those which affect the caribbean originate over the tropical waters off the coast of West Africa where temperatures are about 30.

Question 29

Conditions favouring the development of hurricanes

Answer 29

Warm tropical water about 30 C
Coriolis effect north and south of latitudes 10N and S. This causes the spiral motion of the hurricane and can influence its path
Divergent upper level winds allowing up draughts of air