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In this study, an ensemble of statistically downscaled 14 multi‐global climate models for RCP4.5 and RCP8.5 emission scenarios was employed to implement a comprehensive assessment of climate change impacts over Pakistan in order to identify the future hotspots cities in terms of changes in temperature and precipitation. The analyses focused on the minimum, maximum and average temperature and precipitation in three time‐slices: 2006–2035, 2041–2070, and 2071–2,100. Average temperature is projected to increase by 2.6°C under RCP4.5 while 5.1°C under RCP8.5 by the end of this century with the north side of Pakistan (mainly over North Pakistan—NP, Monsoon Region—MR and Khyber Pakhtunkhwa—KP) presenting the highest changes in the temperatures. Wetter conditions are expected in the future over Pakistan, mainly over the MR. In general, air temperature and precipitation showed linear positive correlation over Pakistan in both RCP scenarios. Hotspot cities where extreme climate, that is, the hottest, dryer and wetter, exists were also identified. Hyderabad will likely become the hottest city of Pakistan by end century with the highest average temperature reaching 29.9°C under RCP4.5 and 32.0°C under RCP8.5 followed by Jacobabad, Bahawalnagar, and Bahawalpur. Most of the hottest cities are detected in areas on the southern side of Pakistan. On the other hand, the wettest cities, Murree, Balakot and Muzaffarabad, are located in the MR. Dry conditions are likely to be prevalent in Dalbandin followed by Khanpur and Jacobabad under both RCPs. The uncertainties of the projections were also evaluated. For precipitation, for example, there are a large number of outliers indicating the high variability/uncertainties of the projections. These uncertainties are clearer when the probability density functions are analysed for individual sub‐domains in Pakistan. [ABSTRACT FROM AUTHOR]

Abstract Climate change is a phenomenon that is unequivocally altering the natural systems in all parts of the world but the alteration in climate extremes may pose more severe and unexpected impacts on Pakistan. The current study provides a comprehensive outlook of observation (1976–2005) and changes in climate extremes between the reference (1976–2005) and future periods (2020s: 2006–2035, 2050s: 2036–2065 and 2080s: 2066–2095). The analysis was conducted across six sub-regions of Pakistan including North Pakistan (NP), Monsoon Region (MR), Khyber Pakhtunkhwa (KP), Southern Punjab (SP), Balochistan and Sindh for which Coupled Model Intercomparison Project Phase 5 (CMIP5) 14 General Circulation Models (GCMs) under Representative Concentration Pathways 4.5 (RCP4.5) and RCP8.5 were downscaled and bias corrected by three statistical downscaling methods. The spatial disaggregation and quantile delta mapping (SDQDM) method was used for future projections in this study. Changes in climate extremes were detected by Expert Team on Climate Change Detection and Indices (ETCCDI). In case of temperature, the results indicate a projected increase in frequencies and magnitudes for warm extremes, while it is decreasing for cold extremes in the 21st century. The corresponding trends of maximum and minimum temperature extremes are greater than the mean temperature trend; where the frequency and magnitude of minimum temperature extremes is higher than maximum temperature extremes over Pakistan particularly over North in last half of the 21st century for both RCPs. Also, the average of temperature extremes (TXx, TXn, TNx and TNn) are severe in the order of NP (+4.8 °C), KP (+4.6 °C) and MR (+4.5 °C). In the case of precipitation extremes, most of the sub-regions across Pakistan show a higher increase in total annual precipitation and intense precipitation events with the highest increase in MR, KP and NP and the least increase in Sindh. Despite the increase in total precipitation, numbers of consecutive dry days (CDD) are increasing while consecutive wet days (CWD) are decreasing which can give rise to drought conditions particularly in Sindh. The study provides complementary and consistent climate extremes information over Pakistan for local decision makers to incorporate into policy-making, disaster management, and infrastructure planning. Highlights • Future extreme events over Pakistan are projected by using spatial disaggregation and quantile delta mapping (SDQDM) statistical downscaling method. • Results show that in 21st century, Pakistan is expected to experience more warm extreme events. • The highest increase in extreme temperature events is expected in North part of Pakistan. • Extreme precipitation events are also projected to increase particularly in North and Khyber Pakhtunkhwa. [ABSTRACT FROM AUTHOR]