A Level H2 Geography Physical Geography Quiz

Answer Key - A-Level Geography H2 Quiz (Physical Geography)

Section A: Tropical Environments

1. Latent Heat (4m): Energy absorbed/released during a phase change (e.g., water vapor to liquid). In cyclones, latent heat is released during condensation in the eyewall, warming the surrounding air, lowering pressure further, and fueling the storm's intensity.
2. Af vs Aw (4m): Af (Rainforest) has no distinct dry season (all months >60mm). Aw (Savanna) has a pronounced dry season, usually during the winter, leading to different vegetation (grasses vs. dense forest).
3. Vertical Structure (5m): Emergent layer (tallest trees, sunlight), Canopy (continuous layer, intercepts rain/light), Understory (low light, shade-tolerant), Forest Floor (dark, rapid decomposition).
4. Leaching (6m): Heavy tropical rainfall percolates through soil, dissolving soluble minerals (bases) and carrying them deep into the soil profile or away. This leaves the soil acidic and nutrient-poor (latosols).
5. SST & Intensity (5m): SST must be $>26.5^\circ\text{C}$. Higher SSTs provide more energy (latent heat) via evaporation, which increases the convective strength and wind speeds of the cyclone.
6. Closed Nutrient Loop (8m): High temp/humidity $\rightarrow$ rapid decomposition by fungi/bacteria $\rightarrow$ thin humus layer $\rightarrow$ shallow root systems (buttress roots) rapidly re-absorb nutrients $\rightarrow$ nutrients stay in biomass rather than soil.
7. ITCZ Shift (6m): ITCZ follows the solar zenith. NH Summer: shifts North (causing monsoon rains in India/SE Asia). SH Summer: shifts South (causing wet seasons in Brazil/Central Africa).

Section B: Geomorphology & Hazards

8. Mass Movement (4m): e.g., Rockfall (rapid, free-fall) vs. Soil Creep (extremely slow, gradual). Difference: Speed of movement or the nature of the material (solid rock vs. soil/regolith).
9. Carbonation (6m): Rainwater absorbs $\text{CO}_2$ to form weak carbonic acid ($\text{H}_2\text{CO}_3$). This reacts with calcium carbonate ($\text{CaCO}_3$) in limestone to form soluble calcium bicarbonate, which is washed away.
10. Sinkhole (6m): Surface depression formed either by the gradual dissolution of limestone from the surface downwards or the collapse of the roof of an underground cavern.
11. Pore-water Pressure (7m): Water fills gaps between particles $\rightarrow$ increases lubrication (reduces friction) $\rightarrow$ increases weight (load) $\rightarrow$ increases pore-water pressure which pushes particles apart, reducing shear strength of the slope.
12. Weathering vs Mass Movement (4m): Weathering is the in situ breakdown of rock (chemical/physical). Mass movement is the downslope transport of weathered material under gravity.
13. Joints/Bedding Planes (7m): Limestone is permeable via secondary porosity. Water enters vertical joints and horizontal bedding planes $\rightarrow$ widens them via carbonation $\rightarrow$ creates interconnected conduits/caves.
14. Debris Flow (8m): Rapid, fluid-like movement of saturated soil/rock. More hazardous than slumps because of higher velocity, greater momentum, and ability to travel further from the source.

Section C: Environmental Systems & Synthesis

15. Deforestation & Hydrology (8m): Less transpiration $\rightarrow$ reduced atmospheric moisture $\rightarrow$ decreased convectional rainfall. Reduced interception $\rightarrow$ increased surface runoff $\rightarrow$ higher risk of flooding and soil erosion.
16. Evapotranspiration (6m): Combined process of evaporation from surfaces and transpiration from plants. In tropics, high rates maintain high humidity, which feeds back into high precipitation levels.
17. Coriolis Effect (6m): Deflects wind to the right in NH and left in SH. This creates the counter-clockwise rotation of cyclones in the NH and clockwise rotation in the SH.
18. Global Temp & Storms (8m): Warmer oceans $\rightarrow$ more latent heat $\rightarrow$ potentially more intense storms (higher category). Changes in atmospheric pressure gradients may shift the frequency or tracks of these storms.
19. Environmental Equilibrium (6m): A state of balance where inputs (energy, nutrients) equal outputs. In tropics, the balance between rapid growth and rapid decomposition maintains the system.
20. Hard vs Soft Engineering (10m): Hard (Retaining walls, shotcrete): Immediate, high cost, may fail catastrophically, disrupts aesthetics. Soft (Afforestation, zoning, drainage): Sustainable, lower cost, takes time to work, works with natural processes. Evaluation: Soft is better for long-term sustainability; hard is necessary for critical infrastructure.