UPSC Prelims 2026 Q33: Climate of Andaman & Nicobar Islands Explained
With reference to the climate of Andaman and Nicobar Islands, which of the following statements is/are correct?
1. The climate can be defined as a humid, tropical coastal climate.
2. It receives rainfall from both South-west monsoon and North-east monsoon.
3. Maximum precipitation is between December and May.
- 1 only
- 1 and 2
- 2 and 3
- 3 only
Answer: (b) 1 and 2
Statement-wise explanation
- 1: correct — The A&N administration's own description says the islands' climate 'can be defined as humid, tropical coastal climate'. Temperatures stay at about 23–31°C all year, humidity is high (around 80%), and sea breezes keep the range small. Every month averages well above 18°C, so in Koeppen's scheme this is a tropical humid (Group A) climate, of the monsoon (Am) type.
- 2: correct — The islands sit in the Bay of Bengal, so both monsoon systems pass over them. The south-west monsoon reaches the Andaman Sea first in India, around mid-to-late May; in 2026 it arrived on 16 May. The north-east (retreating) monsoon, together with Bay of Bengal depressions and cyclones, brings more rain in October–December.
- 3: incorrect — The official description puts maximum precipitation between May and December, not December to May. Studies give a mean annual rainfall of about 3,180 mm, and about 90% of it falls in the summer monsoon (mid-May to early October). January to April is the driest stretch, with only about 15–55 mm a month. The statement has reversed the season.
How to eliminate
Statement 1 can be judged from basic knowledge. Islands near 6–14°N, surrounded by warm sea, cannot be anything but humid and tropical. Statement 3 can be caught by applying the all-India monsoon calendar: the south-west monsoon reaches the Andaman Sea in May and dominates June–September, so the rain cannot peak in December–May. Once statement 1 is true and statement 3 is false, the only option left is the one with 1 and 2. Statement 2 needs only one fact: the islands lie in the Bay of Bengal, in the path of the north-east monsoon and post-monsoon cyclones, just like Tamil Nadu. Fact to remember: 'both monsoons, maximum rain May–December'.
Know more
Why the Andaman & Nicobar Islands get two monsoons
The islands lie between about 6°N and 14°N in the Bay of Bengal. Two things follow from that position:
- The first Indian landfall of the south-west monsoon. IMD tracks the monsoon's arrival over the Andaman Sea in mid-to-late May, about 10 days before Kerala (normal onset 1 June). In 2026 it reached the Andaman Sea and Nicobar Islands on 16 May.
- Exposure to the north-east monsoon. From October to December, north-easterly winds pick up moisture over the Bay of Bengal. Depressions and cyclones that form there also cross the islands, so the rain goes on after the south-west monsoon retreats.
| Feature | Andaman & Nicobar | Lakshadweep |
|---|---|---|
| Sea | Bay of Bengal | Arabian Sea |
| Origin | Mostly mountains continuing the Arakan Yoma (tectonic), plus volcanic Barren and Narcondam | Coral atolls |
| Annual rainfall | ~3,000 mm or more | ~1,500–1,600 mm |
| Monsoons | South-west and north-east | Mainly south-west |
| Wettest period | May–December | June–September |
Climate type: Every month averages above 18°C (about 23–31°C), with a short, relatively dry spell from January to April. That makes it Koeppen's tropical monsoon (Am) climate, a subtype of Group A tropical humid climates. The sea keeps the daily and seasonal temperature range small, which is why it is described as coastal.
Exam angle: UPSC likes to reverse seasons, as in 'December to May' instead of 'May to December'. Check every month range against the monsoon calendar: SW monsoon June–September, retreating or NE monsoon October–December, dry or hot season January–May.
In the news
The 2026 south-west monsoon reached the Andaman Sea and Nicobar Islands early, on 16 May 2026, a week before the Prelims. Great Nicobar development was also in the news. The question itself tests static climatology.
NCERT Concepts to Revise
- Tropical monsoon climate: Statements 1 and 3 depend on how the tropical monsoon (Am) climate works: high heat and humidity all year, with a long wet season and a short dry one.
- Tropical humid climates (A): Statement 1 depends on Koeppen's Group A rule that every month averages above 18°C, which the islands' steady 23–31°C temperatures can be checked against.
- Monsoon: Statements 2 and 3 depend on when the south-west monsoon (from mid-May) and the retreating north-east monsoon (October–December) bring rain to the Bay of Bengal islands.