region of the state of Punjab. For administrative purposes, it has been placed in the Patiala Division. It lies between north latitude 30°-34' and 31°-01' and east longitude 75°-18' and 76°-20'. It is bounded on the north by the Satluj River, which separates it from Jalandhar district. The river forms its northern boundary with Hoshiarpur district. On other sides it shares common boundaries with Rupnagar district in the east, Moga district in the west, and Barnala, Sangrur and Patiala districts in the south and southeast, respectively. Topography The topography of the district is a typical representative of an alluvial plain. It owes its origin to the aggravation work of the Satluj River. The alluvium deposited by the river has been worked over by the wind, which gave rise to a number of small dunes and sand mounds. Most of these dunes have been leveled by farmers. The district can be divided into the flood plain of the Satluj and the upland plain. Climate Ludhiana features a semi-arid climate under the Köppen climate classification, with three defined seasons; summer, monsoon, and winter. This climate is characterized by dryness except for a brief spell of monsoon season, a very hot summer, and a bracing winter. The cold season is from mid-November to the early part of March. The succeeding period until the end of June is the hot season. July, August and half of September constitute the southwest monsoon. The period of mid-September to about the middle of November may be termed as a post-monsoon or transitional period. June is generally the hottest month. Hot and scorching dust-laden winds blow during the summer season. December and January are the coldest months. Ludhiana on average sees roughly of precipitation annually. The official weather station for the city is in the compound of the Civil Surgeon's Office to the west of Ludhiana. Weather records here data back to 1 August 1868. Rainfall The rainfall in the district increases from the southwest toward the northeast. About 70% of the rainfall is received during the period of July through September. The rainfall between December and March accounts for 16% of the rainfall; the remaining 14% rainfall is received in the other months. Pollution Ludhiana has one of the worst air pollution problems in India, with particulate matter being over six times the World Health Organization recommended standard, making it the 13th most polluted city in the