Regional overview of climate change impacts Summary Based on the latest scenarios of the IPCC, the representative concentration pathways, the data from the AR 4 in 2007 underestimated the expected changes. Provided that the RCP 8.5 seems at present to be the more likely scenario, changes of 2.7 to 3.0 deg C have to be expected in Nepal and Pakistan by 2050, representatively. Precipitation is expected to increase to a larger extent than expected in Nepal with about 120 mm increased precipitation by 2050. In Pakistan the increase is marginal and less than was expected in 2007. The working districts expect similar rates of change in the case of Pakistan, while in Nepal higher temperature increases are expected for high altitude districts and precipitation is expected to increase more in the working districts, especially at lower altitude. Acknowledgement: The statistics of the downscaled data for the RCPs was received from Dr. Robert Zomer, Kunming Institute of Botany, who processed the data as part of an International Research Development Center funded and Kunming Institute of Botany-HELVETAS Swiss Intercooperation implemented project on the Asian Highlands (www.asianhighlands.org) Overview On the basis of the IPCC scenarios in 2007 Karmacharya (2007) identified a change in temperature of 1.7 to 2.4 deg C for South Asia and 1.9 to 2.6 deg C by 2050 in the Central Himalaya, respectively (Table 1). Table 1: Changes of temperature and precipitation based on IPCC AR 4 scenarios (Karmacharya et al., 2007) Temperature Change [deg C] 2050s Precipitation Change [mm] 2050s Scenario South Asia B1 1.7 A1B 2.4 A2 2.2 45.8 73.0 53.0 Central Himalaya B1 1.9 A1B 2.6 A2 2.4 49.3 84.9 58.4 These assessments showed a general increase in temperature of about 1.5 to 2.5 deg C and a precipitation increase of between 50 and 75 mm in South Asia depending on the different scenarios. The Central Himalaya is expected to experience a slightly higher increase in temperature as well as a higher increase in precipitation. Based on the latest scenarios of the IPCC, the representative concentration pathways, the data from the AR 4 in 2007 underestimated the changes (Table 2). Provided that the RCP 8.5 seems at present to be the more likely scenario, changes of 2.7 to 3.0 deg C have to be expected in Nepal and Pakistan, representatively. Precipitation is expected to increase to a larger extent than expected in Nepal with about 120 mm increased precipitation by 2050. In Pakistan the increase is marginal and less than was expected in 2007. Table 2: Changes of temperature and precipitation based on IPCC AR 5 scenarios (Robert Zomer, personal communication) Area Nepal Pakistan Temperature [deg C] Year 2050: Year 2050: RCP 4.5 RCP 8.5 2.2 2.7 2.5 3.0 Precipitation [mm] Year 2050: Year 2050: RCP 4.5 RCP 8.5 116 121 9 26 Nepal Overall temperatures and precipitation in Nepal are expected to increase overall throughout the country, however the rates of change differ even within the proposed working districts. The highest temperature increase is expected for high altitude districts where up to 3 deg C change are expected depending on the scenario. Precipitation changes on the other hand are expected to be higher in the lower situated districts, e.g. Surkhet and Achham. In these districts up to 170 to 220 mm are predicted. Table 3: Precipitation and temperature Nepal (data: Zomer, personal communication) Area Achham Dailek Jajarkot Jumla Kalikot Surkhet Nepal Precipitation [mm] Year 2000 Year 2050: Year 2050: RCP 4.5 RCP 8.5 1381 1512 1540 1322 1451 1474 1157 1253 1266 828 883 889 933 1003 1014 1643 1839 1873 1373 1489 1494 Temperature [deg C] Year 2000 Year 2050: Year 2050: RCP 4.5 RCP 8.5 18.5 20.7 21.3 17.3 19.5 20.1 13.6 15.9 16.4 6.8 9.3 9.9 11.6 13.9 14.5 20.7 22.8 23.3 14.1 16.3 16.8 Figure 1: Mean temperature (data: Zomer, personal communication) Figure 2: Precipitation Nepal (data: Zomer, personal communication) Pakistan Precipitation throughout Pakistan is not expected to change significantly, however a slight increase of 20 mm can be expected. However, in the working districts slightly higher precipitation is expected at the rate of about 60 to 80 mm. Temperatures are expected to increase by about 3 deg C depending on the scenario. In the working districts temperature increases are expected at the same rate. Table 4: Pakistan (data: Zomer, personal communication) Area Attock Chakwal Haripur Swabi Pakistan Precipitation [mm] Year 2000 Year 2050: Year 2050: RCP 4.5 RCP 8.5 540 566 600 493 523 564 917 943 990 697 720 750 313 322 339 Temperature [deg C] Year 2000 Year 2050: Year 2050: RCP 4.5 RCP 8.5 22.4 24.9 25.4 22.4 24.9 25.5 20.6 23.2 23.7 21.6 24.2 24.8 19.1 21.6 22.1 Figure 3: Pakistan temperature (data: Zomer, personal communication) Figure 4: Pakistan precipitation (data: Zomer, personal communication) Outlook At present the analyses of the data is only based on annual statistics as only statistics have become available at this time. As soon as the raw data becomes available, more detailed analyses on the basis of seasonal and monthly temporal disaggregation can be conducted. These analyses are expected to present more distinct pictures of the expected changes. Annex 1: Nepal Achham Annex 2: Pakistan Attock