Module 3 - Weather and Climate

Question 1

Name the four factors that influence the climate in South Africa.

Answer 1

Benguela current, Agulhas current, Altitude, Latitude.

Question 2

Explain Anabatic and Katabatic wind.

Answer 2

Anabatic Wind:
Early in the morning when air on the
hillside is warmed up the air becomes less dense and rise up. Evident in form of fog rising out of the valleys.

Katabatic Wind:
Often at night when air on higher ground cools due to radiation and moves down the hill-slope. Evident in gusts of wind.

Question 3

What is a cold front associated with, what is the approaching conditions and the conditions when it passes?

Answer 3

Temperature: Warm/Cooling/Colder
Precipitation: Showers/Heavy rain/Showers & clearing
Clouds: Cumulus/Cumulonimbus/Cumulus

Question 4

Where do winds come from?

Answer 4

Winds are created by the movement of air from areas of HP (High-Pressure) to those of LP (Low-Pressure), caused by different temperatures.

Question 5

Seasonal Weather System:

General, South (Western Cape), Inlands (Eastern cape)

Answer 5

General:
Subtropical High-Pressure system with dry, stable conditions
South (Western Cape):
Summer: HP, no rain, dry;
Winter: LP, rainfall, cold
Inlands (Eastern Cape):
Summer: HP from Indian Oceans develops LP with unstable air and thunderstorm;
Winter: HP, stable dry air with sunny dry days and cold nights

Question 6

Weather vs Climate

Answer 6

Weather: How hot, cold, wet, … in a particular area over short time
Climate: average weather conditions over long periods (30 years)

Question 7

Drivers for climate and weather patterns

Answer 7

1. Earth’s spin (west to east)
2. Geographical position (distance to ocean and latitude)
3. Altitude

Question 8

Coastal low

Answer 8

Small Low Pressure Cell moving East- and northwards along coast (mist, drizle)

Question 9

Tropical cyclone

Answer 9

Small intense cell along Mozambique coast. Stormy weather, strong wind, heavy rainfall

Question 10

Cyclone

Answer 10

Rotating Low pressure cell moving upwards in clockwise direction

Question 11

Anticyclone

Answer 11

Rotating High Pressure, downward sinking and anticlockwise. Clouds and rainfall

Question 12

Mid-lattitude cyclone

Answer 12

Large cyclones, contain cold- and warmfronts. Overcast conditions. between 30° and 60° north and south

Question 13

What is a warm front associated with, what is the approaching conditions and the conditions when it passes?

Answer 13

Temperature: Cool/Warming/Warmer
Precipitation: Showers/Drizzle/None
Clouds: Cirrus & Stratus/Stratus/Scattered Stratus