Climate of Punjab 
Analysis of inter-annual variability of area weighted seasonal monsoon rainfall expressed as the percentage departures from long period average (LPA) for the period 1901-2011 for Punjab indicates that during the period 1901 -2011, the lowest and second lowest seasonal rainfall in Punjab have occurred in 1911 (-51.0%) and in 1987 (-67.6%) respectively. Highest and second highest seasonal rainfall in Punjab have occurred in year 1950 ( 91.2%) and in 1988 ( 119.1%).
Further, during 2017, the state received 493.0 mm of rainfall. The rainfall in various districts varied from 93.7 mm in Firozpur to 1273.3 in Gurdaspur. Figure 27 highlights the average actual rainfall and departure from the normal (as defined by the rainfall records of 1951 to 2000) by districts of Punjab for the year 2017.
Data analyzed by the Indian Meteorological Department indicates that the temperatures over Punjab have been rising over the years as it is elsewhere in India and the world, and in 2010 the maximum and minimum temperatures in the Punjab region have increased by 0.5-1.0oC with respect to the base line 1971-2000. There have been spatial variations in precipitations across the years with some years experiencing more than normal rain fall and some years experiencing deficit rainfall.
The annual mean maximum temperature is projected to increase by 1.0-1.8oC with respect to the base line in all parts of Punjab by 2021-2050. By the end of the century, however, the mean maximum temperature may increase further by 4.0 to 4.4oC. The annual mean minimum temperature is also projected to rise by 1.9-2.1oC by mid-century with respect to base line (1961-1990), and it is likely to increase further by 4.4 to 5.1oC at the end of the century.
An overall increase in annual precipitation is projected in the mid (2021-2050) century by about 13.3%-21.5% with respect to base line 1961-1990. On a seasonal basis, in the mid-century (2021-2050), the precipitation is likely to increase by 11.5-20.8% during the monsoon period (June-July-August-September) in the entire state with respect to the base line. The increase is likely to be higher in the post- monsoon period (October-November-December) ranging between 30.0-63.9%, with precipitation increasing from east to west. In the winter period (January-February), the precipitation shows a decrease in most areas of the state by upto 21.8%with respect to base line. In the pre-monsoon period (March-April-May), all parts of Punjab are likely to experience a mixed trend, with change ranging between -4.7 to 29.1% with respect to base line.
Climate projections for 2021-2050s and 2071-2098 for Punjab have been derived from Providing Regional Climate for Impact Studies developed by the UK meteorological department, the projections of climate for India have been made, which is run on A1B IPCC GHG scenario.
The simulation dataset is provided by the Indian Institute of Tropical Meteorology, Pune. PRECIS is a portable version of the HadRM3 regional climate change model, developed by the Hadley Centre UK. The model outputs have a spatial resolution of 0.44° x 0.44° (50km x 50km).
The climate change scenarios are driven by the IPCC GHG emission scenarios - A1B (IPCC, SRES, 2001), which assumes a future world of very rapid economic growth, a global population that peaks in mid-century and declines thereafter, and assumes rapid introduction of new and more efficient technologies.
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