and the North-East monsoon (October to November). The South-West monsoon is usually very heavy. About 75% of its annual rainfall is received during this season. The town enjoys a tropical climate, the monsoons start in June. The months of April–May can get pretty humid. The best weather is from October to February. Pathanamthitta experiences three distinct seasons: summer, monsoon and winter. Typical summer months are from March to May. The warmest month in Pathanamthitta is April. Although summer doesn't end until May, the city often receives locally developed heavy thundershowers in May (although humidity remains high). The monsoon lasts from June to August, with moderate rainfall. Most of the heavy rainfall in the city falls between June and July, and June is the wettest month of the year. The Last weeks of June is also days of floods. The three major rivers viz Pampa, Achankovil and Manimala swell with rainwater. Winter begins in December. December through February are the winter months. The lowest temperatures are experienced during January. According to the latest World Health Organisation (WHO) study on ambient air quality among 123 Indian cities, Pathanamthitta was found to have the cleanest air in India, in terms of least concentration of dust particles in air. Two out of the three least polluted cities in India are from Kerala, Kollam being the second least polluted. As per the database, in Pathanamthitta, the annual mean of PM10 and PM2.5 is recorded at 23 and 10 respectively, which is closer to the recommended level of concentration of particulate matter. While a number of Indian cities are among the world's most polluted, Pathanamthitta's air quality is comparable to some of the cleanest cities in North America, Europe and Australia. Economy Agriculture Agriculture is the main occupation of the people. About 75% people are dependent on this sector. Rubber is the most important crop, with its plantations covering over . The hilly terrain coupled with high humidity makes the region suitable for rubber plantations. Paddy is the most important crop cultivated in the wet lands. Tapioca and pulses are the important dry land crops. Other major crops are coconut, banana, pepper and ginger. In certain areas cashew, pineapple, sugarcane, cocoa and other tree spices are cultivated. The land available for cultivation is less since sizeable area of the district is reserve forest. Source : Statistics for Planning-DES 2006 Fisheries Pathanamthitta district has a unique position