Outlook on climate change adaptation in the Hindu Kush Himalaya

Precipitation While there is a clear warming trend across the HKH, there has been no consistent long-term trend for precipitation levels since the second half of the twentieth century, as some areas have become drier, while others have become wetter (Singh et al., 2011; Gautam et al., 2013; Shrestha et al., 2015a). The task of identifying which regions have become wetter or drier is further complicated by the different geographic scales through which the studies are conducted. The table below identifies a number of studies from specific subregions, basins and countries, and their conclusions.

major river basins, namely the Brahmaputra, Ganges, Indus, Mekong and Salween basins. They found that in southern HKH areas, minimum temperatures have increased during winter months (December, January and February), whereas higher altitude areas in northern HKH areas have experienced colder winters as minimum temperatures have sharply decreased. Some of these areas have also experienced higher maximum temperatures, indicating that seasonal extremes are increasing, which has been identified as a trend across the region in various reports (Gautam et al., 2013).

changes in seasonal temperatures vary within the region (Kulkarni et al., 2013), as does the warming rate between seasons (Gautam et al., 2013). In large parts of the region, and especially in the central Himalayas (the Chinese northwest, Indian and Nepalese Himalayas), winter months have seen a higher warming rate than other seasons (Bhutiyani et al., 2007; Bhutiyani et al., 2010; Shrestha et al., 1999; Shrestha and Devkota, 2010; Shrestha et al., 2012). Shrestha et al. (2015a) have studied observed and future impacts of climate change in five of the region’s

Geographic region Northwestern Himalayas

Precipitation trend Decreasing monsoon and annual precipitation (Bhutiyani et al., 2010) Decreasing but inconsistent winter precipitation (Dimri and Dash, 2012; Guhathakurta and Rajeevan, 2008) Increasing annual, winter and summer precipitation (Archer and Fowler, 2004)

Western (Indian) Himalayas

Upper Indus Basin

Koshi River Basin

Increasing annual precipitation (Shrestha et al., 2016)

Eastern Himalayas

No significant difference in precipitation (Shrestha and Devkota, 2010)

Nepal (whole country)

Mostly insignificant changes; significant increase in pre-monsoon and monsoon precipitation for a few districts; significant increase in winter and post-monsoon precipitation for only a few districts; significant decrease in pre-monsoon precipitation for only one district (DHM, 2017) Increasing annual precipitation (You et al., 2007; Xu et al., 2008; Wu et al., 2007; Qin et al., 2010)

Chinese Himalayas

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