Refer to FIGURE 1.1 showing stages in the development of a mid-latitude cyclone - NSC Geography - Question 1 - 2018 - Paper 1

The stage of development of the mid-latitude cyclone at X is the Wave/Formative stage.

The lowest air pressure recorded in stage Y is 1,000 hPa.

The mid-latitude cyclone Z is older.

The stage of development of the mid-latitude cyclone at Z is the Occlusion/Occluded stage.

Evidence suggesting that the illustrated mid-latitude cyclone is in the Southern Hemisphere includes the clockwise rotation of air and the presence of the subcontinent of southern Africa visible on the map.

The term used to describe mid-latitude cyclones that are linked to one another is Family of cyclones or Cyclone families.

Rivers that flow all year round are permanent rivers.

Periodic rivers flow during the rainy season.

Exotic rivers only flow after heavy rainfall and are known as episodic rivers.

The majority of rivers in South Africa are periodic.

In permanent rivers, the river bed is always below the water table.

The water table is always below the river bed in exotic rivers.

Periodic rivers flow all year round because they are fed by tributaries in high rainfall areas.

Permanent rivers are characteristic of interchanging seasons of high and low rainfall.

Sketch A indicates a winter condition.

Evidence from the sketch indicates that a winter condition is suggested by features such as the presence of snow and cloud formations typical in winter.

The inversion layer forms in sketch A due to a stronger subsiding cold air mass from the Kalahari High Pressure which descends onto a weaker (warmer) air mass, creating an inversion layer.

The change in the height of the inversion layer in sketch B can be accounted for by the seasonal variation and temperature differences between summer and winter, which impact the mixing layers of the atmosphere.

The altitude of the inversion layer over the plateau significantly influences the climate in the interior of South Africa. In summer, warmer air at higher altitudes is trapped beneath cooler air, leading to poor air quality and increased humidity. Additionally, this inversion layer inhibits vertical mixing, causing hot days followed by cool nights. Conversely, during winter, the inversion can lead to prolonged temperature inversions, resulting in colder conditions with widespread fog. Such atmospheric conditions contribute to varying microclimates in different regions, affecting agriculture and local weather patterns.

The site of Pietermaritzburg was a poor choice for the development of a city due to its location on the valley floor, which makes it prone to pollution concentration and adverse weather conditions.

Evidence from the article indicates that pollution levels are much higher in winter due to increased traffic congestion and thermal inversions, which trap pollutants close to the ground.

The local wind that causes the 'brown haze' to disappear is known as the anabatic/up slope wind.

One characteristic of the anabatic/up slope wind is that it rises along slopes, effectively dispersing pollutants as it ascends.

A labeled sketch should illustrate how warm air rises along the valley slopes under the influence of the solar heating and indicate the correct wind direction through appropriate arrows and labels.

The 'brown haze' is a safety hazard for motor vehicle users because it reduces visibility, leading to increased risk of traffic accidents.

The drainage pattern labelled A is a trellis pattern, while the pattern labelled B is a rectangular pattern.

The underlying rock structure for drainage pattern A is folded sedimentary rocks/alternating hard and soft rock layers, while for pattern B, it is typically rocks with joints/cracks/faulted rocks.

A similarity between drainage patterns A and B is that they both exhibit a strong geological influence on their shapes.

A difference between drainage patterns A and B is that in A, the streams follow a steeper, more direct path, whereas in B, the streams exhibit right-angle bends.

The tributaries in drainage pattern A are short due to the steep gradient of the land, which limits their development into longer channels.

The main streams in drainage pattern B have 90° bends due to the structural influence of underlying fault lines and joints in the rock layers, directing the flow in sharp angles.

A delta is a landform created by the deposition of sediment as a river enters slower-moving water such as an ocean, sea, or lake.

Evidence from the photograph that indicates a delta includes sand deposits at the river mouth and the branching of distributaries as the river splits into smaller streams near its mouth.

The feature labelled A is the distributary.

The formation of feature A, the distributary, occurs when the river's sediment load becomes too heavy, causing parts of the river to divert and form smaller channels that lead away from the main flow.

Some coastlines are not suitable for the development of deltas due to factors like strong tidal currents which wash away sediments before they can accumulate.

Deltas are ideal for farming due to their nutrient-rich soil, which is replenished by the regular deposition of sediments from river flooding. The flat landscape allows for easy irrigation, providing water for crops. Additionally, the diverse ecosystems found in deltas can support various agricultural activities. The proximity to water sources enables fishing and aquaculture, further enhancing local food security. Crop diversity thrives in this environment, helping promote sustainable agricultural practices, fostering a robust farming economy in delta regions.