Which of the following pairs of type of climate and area is NOT correct? I. Semi-arid steppe climate - Punjab. II. Monsoon with dry summer - Coromandel coast of Tamil Nadu.

The correct answer is A, the north-east monsoon. As the monsoon retreats in October and November the wind direction reverses and air moves from the land towards the sea. Crossing the Bay of Bengal it picks up moisture and strikes the Coromandel coast, giving Tamil Nadu and coastal Andhra Pradesh their main rainy season. This is why Tamil Nadu is the one large part of India whose farming calendar depends on winter rather than summer rain.

Option B, local air circulation, produces land and sea breezes that are too small to give a season of rain. Option C, temperate cyclones, are the western disturbances, and they bring winter rain to the north-west of India, not to the far south. Option D, the south-west monsoon, leaves Tamil Nadu dry because the state lies in the rain shadow of the Western Ghats during those months.

The correct answer is D, Karnataka. The pre-monsoon thundery showers of Karnataka are called cherry blossom showers or blossom showers because they help the coffee plants of the Kodagu, Chikkamagaluru and Hassan belt to flower. The same family of pre-monsoon showers is called mango showers in Kerala and coastal Karnataka because it helps mangoes ripen, and the two names are often asked together.

Option A, Gujarat, has no such local shower in the standard list. Option B, Meghalaya, is known for the heaviest rainfall of the country at Mawsynram and Cherrapunji, but that rain comes from the Bay of Bengal branch of the monsoon. Option C, Uttarakhand, receives winter precipitation from western disturbances and monsoon rain in summer, and neither is called a blossom shower.

The correct answer is B, the monsoon trough. The monsoon trough is the belt of low pressure that lies across the northern plains during the rainy season and guides the depressions that bring rain. As the sun appears to move south of the equator after the September equinox, the land cools, the low pressure weakens and the trough is replaced by high pressure. That retreat of the trough is what is called the withdrawal or retreat of the monsoon, and it begins from north-west India in early September.

Option A, an upper level trough, belongs to the upper air circulation and is not the feature described here. Option C, a lee trough, forms on the sheltered side of a mountain and is a local feature. Option D, an inverted trough, is a name used for a monsoon trough that extends into the Bay of Bengal in a particular shape, not the plains feature that weakens in October.

The correct answer is B, isohyet. An isohyet is a line drawn on a map through all the places that receive the same amount of rainfall in a given period. Rainfall maps of India are drawn with isohyets, and the crowding of these lines along the Western Ghats shows how sharply rainfall falls from the windward coast to the rain shadow of the plateau.

Option A, an isobar, joins places of equal atmospheric pressure and is used on weather charts to locate depressions and anticyclones. Option C, an isotherm, joins places of equal temperature and is used on temperature maps. Option D, an isohaline, joins places of equal salinity and belongs to the study of the oceans. All four terms carry the Greek prefix iso, meaning equal, and examiners rely on a candidate confusing them.

The correct answer is C, 1 June. The south-west monsoon normally sets in over the Kerala coast about the first of June, and the sudden heavy downpour that marks its arrival is called the burst of the monsoon. From Kerala it advances in two branches, one over the Arabian Sea and one over the Bay of Bengal, covering Mumbai by about the tenth of June and the whole country by about the middle of July.

Option A, the first of April, falls in the hot weather season when the land is only beginning to heat. Option B, the first of May, is still the season of pre-monsoon showers such as mango showers and Kal Baisakhi. Option D, the first of July, is far too late, because by then the monsoon has already covered most of the country and the plains are in full rain.