Regions of the Asian continent differ widely in their biophysical characteristics hence in their physical vulnerability to climate change. Different regions also experience highly differentiated social vulnerability. Adaptation strategies therefore will be differentiated across regions and sectors, depending on their vulnerability profiles. In the following subsections, vulnerabilities and related adaptation strategies are discussed for four broad regions of Asia and for selected sectors.
At present, only areas of sporadic permafrost are used for agriculture. Global warming should play a positive role for agriculture in boreal Asia. The growing season is likely to expand by 1-1.5 months by 2100. The increase in mean monthly air temperatures during the summer will increase active soil temperatures. In addition, winter air temperatures will substantially increase (Sirotenko et al., 1997). Shifts in the limit of the permafrost zone to the north, formation of vast areas of perennial ground thawing, and better soil climate will contribute to a northward shift of agriculture boundary. The key step for an agriculture adaptation strategy could be the choice of suitable crops and cultivars. Shifts in sowing date of spring crops will allow more effective use of the soil moisture content formed by snow melting. The dates of spring crop sowing could be moved forward in a crop rotation calendar in southern regions, and farmers could plant a second crop that could even be vegetable with a short growth period (Laverov, 1998). Optimum use of fertilizers and ecologically clean agrotechnologies would be beneficial for agriculture.
Climate change has the potential to exacerbate water resource stresses in some areas but ameliorate them in most parts of boreal Asia. The increase in surface temperatures will have considerable effect on the timing of snowmelt hence the timing of the flow regime (Arnell, 1999). Diversions of water systems would adversely impact fisheries and fishery habitat in the region (Rozengurt, 1991). A decrease in water flow during the dry summer season is likely in some parts of boreal Asia. Extraction of groundwaters from deep aquifers has been proposed as an option, keeping in view the likely surface water quality deterioration during dry periods (Laverov, 1998). It would be necessary to increase the capacity of recycled water supply systems and autonomous water-use systems. However, even with water-saving measures it may be necessary to cut water intake for industry needs during dry periods to meet increasing demand in the future. Bottom-deepening along navigation channels may be required to facilitate the transport of goods and material through rivers.
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