Examkin

Question

Difficulty: HardClimatic Controls and World Climate Types

A meteorological station situated at latitude 14∘N14^\circ\text{N} records the annual climatic summary shown below:

ParameterJanFebMarAprMayJunJulAugSepOctNovDec
Mean Temp (∘C^\circ\text{C})222428313331282728292623
Precipitation (mm)00210451102102301152000

Which Köppen climate group symbol and dominant atmospheric control correctly account for this station's temperature and rainfall regime?

  1. Aw climate, controlled by the seasonal migration of the Inter-Tropical Convergence Zone (ITCZ)Answer
  2. B
    Am climate, controlled by the continuous offshore upwelling of cold ocean currents
  3. C
    BWh climate, controlled by year-round dominance of humid maritime tropical air masses
  4. D
    Cs climate, controlled by winter precipitation brought by onshore prevailing Westerlies

Answer

Aw climate, controlled by the seasonal migration of the Inter-Tropical Convergence Zone (ITCZ)
The station displays a tropical thermal profile where every monthly mean temperature exceeds 18°C. The precipitation pattern shows a severe winter drought (November to March) and a distinct summer maximum (June to September). This pattern matches the Tropical Savanna (Aw) classification, which is governed by the seasonal poleward migration of the Inter-Tropical Convergence Zone (ITCZ) during the high-sun season.

Step-by-Step Solution

1
Analyze temperature values to determine the main Köppen climate group.
The minimum monthly mean temperature is 22°C (December/January), which is well above the 18°C threshold required for Köppen's Tropical 'A' climate group.
Tropical climates (Group A) require every month to have a mean temperature of 18°C or higher.
2
Analyze precipitation distribution to determine seasonal sub-classification.
Total annual precipitation is 742 mm, with five distinct dry months (0–2 mm) in winter and heavy rainfall concentrated between June and September.
A distinct winter dry season with moderate total precipitation characterizes the Tropical Wet-and-Dry or Savanna climate (Aw).
3
Identify the primary atmospheric controlling mechanism for this rainfall distribution.
The summer rain belt corresponds to the northward movement of the ITCZ, bringing moist maritime tropical air, while winter dryness corresponds to the subtropical high pressure belt.
Latitudes around 10°–15°N experience alternating tropical rain belts (ITCZ) in summer and dry trade winds (subtropical high) in winter.

Key Concept

Köppen Tropical Savanna Climate (Aw) and ITCZ Migration Mechanism
Estimated Time:2m 0s
Rate this question

Topics

Climatic Controls and World Climate Types

More questions from this topic