This study investigates the evolution of temperatures at several locations in Pakistan. Data on annual and seasonal minimum (Tn) and maximum (Tx) temperatures from 1950 to 2013 of urban (16 stations), town (11 stations), and rural (nine stations) areas are analysed to establish the mean decadal rate of change in urban, town, and rural temperatures. The homogeneity of the data was assessed using HOMER 2.6. To measure the temporal intensity of change in temperature, the data were split into two different periods: 1950–1981 (P1, phase of less urbanization) and 1982–2013 (P2, phase of highly urbanized period) and were analysed separately for both phases of 32 years each. The per decade changes of annual minimum and maximum temperatures (dTna and dTxa, respectively) over most stations show an increase in temperatures. The trends of annual and seasonal dTn and dTx observed over urban, town, and rural stations during P2 are significantly higher than those observed during P1. The increase in minimum temperatures is more significant than that in maximum temperature, and it is also more significant on urban stations than the town and rural stations. However, the maximum temperatures increase more at town stations than urban and rural stations. Overall, the tendencies in temperatures reflect less change in summer temperatures than other seasons of the year over the whole period.
28 May 2020 in Theoretical and Applied Climatology
The impact of climate change on soil temperatures at Kuujjuaq, Quebec in northern Canada is assessed. First, long-term historical soil temperature records (1967–1995) are statistically analyzed to provide a climatological baseline for soils at 5 to 150 cm depths. Next, the nature of the relationship between atmospheric variables and soil temperature are determined using a statistical downscaling model (SDSM) and National Centers for Environmental Prediction (NCEP), a climatological data set. SDSM was found to replicate historic soil temperatures well and used to project soil temperatures for the remainder of the century using climate model output Canadian Second Generation Earth System Model (CanESM2). Three Representative Concentration Pathway scenarios (RCP 2.6, 4.5 and 8.5) were used from the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). This study found that the soil temperature at this location may warm at 0.9 to 1.2 °C per decade at various depths. Annual soil temperatures at all depths are projected to rise to above 0 °C for the 1997–2026 period for all climate scenarios. The melting soil poses a hazard to the airport infrastructure and will require adaptation measures.