Climate change and spatio-temporal trend analysis of climate extremes in the homogeneous climatic zones of Pakistan during 1962-2019

− 0.137˚C in Gilgit in the recent past. Shahzaman et al. [87] concluded in their study that drought has been observed over central and northern Pakistan during 1982–2019 by integrat- ing various data types. Proportion of South Asian population exposer to heatwaves is increas- ing under the shared socioeconomic scenarios in the twenty first century, however, the northern areas of Pakistan are unaffected presently [88]. The mass balance of the glacier is heavily dependent on the winter accumulation and sum- mer ablation strongly influenced by precipitation and temperature among other factors [89]. This study provides up to date changes in precipitation and temperature in some parts in the northern Pakistan (4 meteorological stations are in the Karakoram region). We found signifi- cant increase in winter average precipitation and decrease in summer average temperature particularly at the meteorological stations in the Karakoram region during the 1962–1990 (Table 1). However, the mMK test indicates a decreasing trend (during DJF) in precipitation and increasing trend (during JJA) in temperature in the recent period of 2010–2019 in the Kar- akoram which is not aligned with the Karakoram Anomaly. Our findings are an indication of glaciers mass loss in future in the Karakoram region. These stations are situated in the valley below the glacier terminating zones, however, an indirect clue can be inferred based on climate change and extreme events regarding future trends. Our results suggest further investigation

of glaciers mass balance in the region in future for better understanding of glaciers’ health and associated impacts. The downstream water availability in UIB is dominated by snow and Table 8. Seasonal MK test results in the Karakoram region for minimum temperature. The table shows the Ken- dall τ and their significance for the 1990–1999, 2000–2009 and 2010–2019. Station DJF MAM JJA SON Station Kendall τ P-Value Kendall τ P-Value Kendall τ P-Value Kendall τ P-Value Minimum Temperature (1990–1999) Astore 3.60e-02 0.11 1.51e-01 8.73e-12 1.61e-01 4.38e-13 -3.14e-04 0.989 Bunji -4.88e-02 0.030 7.85e-02 0.000 1.10e-03 0.960 -4.94e-02 0.026 Chilas 1.12e-01 5.79e-07 1.41e-01 3.23e-10 -7.65e-02 0.001 Darosh 1.13e-01 4.54e-07 1.03e-01 3.33e-06 6.64e-03 0.764 -5.04e-02 0.023 Gilgit -1.56e-01 2.88e-12 9.95e-02 7.01e-06 4.19e-02 0.058 -3.51e-02 0.114 Gopis 3.91e-02 0.086 1.05e-01 2.72e-06 -3.01e-02 0.178 -2.01e-02 0.368 Skardu -6.44e-02 0.004 9.08e-02 4.04e-05 -1.24e-02 0.575 -3.72e-02 0.094 Minimum Temperature (2000–2009) Astore 2.76e-03 0.902 1.07e-01 1.56e-06 7.35e-02 0.001 -7.00e-02 0.001 Bunji 7.40e-02 0.001 7.49e-02 0.001 1.13e-01 3.77e-07 5.98e-02 0.007 Chilas 1.59e-01 3.66e-12 8.46e-02 0.000 3.84e-02 0.089 -3.69e-02 0.100 Darosh -1.91e-01 2.2e-16 -5.36e-02 0.015 -2.88e-01 2.2e-16 -2.30e-01 2.2e-16 Gilgit 1.31e-01 5.39e-09 1.24e-01 2.61e-08 1.84e-01 2.2e-16 3.98e-02 0.074 Gopis -1.94e-01 2.2e-16 2.56e-02 0.250 -6.04e-02 0.007 -1.43e-01 1.46e-10

Skardu 1.05e-02 0.635 -3.29e-03 0.882 -1.48e-01 2.18e-11 -1.51e-01 9.57e-12 Minimum Temperature (2010–2019) Astore -9.41e-03 0.709 5.45e-02 0.028 1.23e-01 9.29e-07 -1.08e-01 1.55e-05 Bunji 2.65e-01 < 2.2e-16 1.41e-01 1.30e-08 1.62e-01 9.06e-11 -7.09e-03 0.777 Chilas 1.18e-01 2.90e-06 9.01e-03 0.716 -1.40e-01 1.66e-08 -1.11e-01 8.16e-06 Darosh 1.31e-03 0.958 -5.57e-03 0.822 1.57e-02 0.527 -7.7e-02 0.001 Gilgit 8.88e-02 0.000 4.42e-02 0.078 1.23e-01 1.16e-06 -9.07e-02 0.000 Gopis 2.13e-01 < 2.2e-16 6.32e-02 0.012 2.14e-02 0.397 -1.11e-01 1.05e-05 Skardu 1.08e-01 1.70e-05 4.59e-02 0.063 2.01e-02 0.418 -4.81e-02 0.053 https://doi.org/10.1371/journal.pone.0271626.t008 PLOS ONE Climate change and extremes analysis using observed data (1962-2019) over Pakistan PLOS ONE | https://doi.org/10.1371/journal.pone.0271626 July 27, 2022 20 / 27