Table 2.

Potential freshwater conservation impact of viticulture under climate change, 2050 RCP 8.5

2050 RCP 8.5Decline in area currently suitable for viticulture, mean % loss (quantiles)*Existing water stress, mean % areaPrecipitation trend to 2050, mean % change (quantiles)Freshwater Impact Index (FII), 2050, mean % area (quantiles)
California70 (50, 64, 77, 83)85.9−2.0 (-26.5, −10.8, 4.2, 16.2)31.3 (0, 2, 61, 71)
Chile47 (23, 35, 59, 81)94.6−15.5 (−29.3, −21.4, −9.8, −0.8)43.0 (10, 24, 62, 80)
Mediterranean Europe85 (54, 80, 96, 100)50.7−8.4 (−20.4, −11.8, −4.1, −0.1)39.1 (5, 14, 20, 22)
Cape floristic region55 (45, 48, 58, 70)44.9−9.8 (−22.4, −10.8, −5.0, −3.1)24.3 (16, 22, 27, 30)
Australia (Med)74 (62, 69, 78, 88)3.0−10.6 (−18.5, −15.8, −4.5, 11.6)1.7 (0, 2, 2, 3)
Australia (nonMed)46 (36, 37, 50, 59)34.6−1.5 (−11.2, −6.0, 2.0, 10.7)14.2 (0, 8, 22, 26)
Northern Europe84 (48, 74, 98, 100)17.2−3.0 (−10.6, −7.1, −0.1, 5.8)16.3 (5, 14, 20, 22)
New Zealand17 (0, 10, 23, 33)0.0−1.2 (−8.1, −3.7, 1.3, 4.7)0 (0, 0, 0, 0)
Western North America59 (34, 52, 72, 78)23.7−0.4 (−9.5, −4.9, 3.5, 9.0)13.8 (0, 7, 21, 27)
  • Ensemble means are shown with quantiles shown in the order 5%, 25%, 75%, and 95%. RCP 4.5 values are given in Table S1.

  • * Decline in area currently suitable for viticulture values indicate areas in which conditions for producing high quality wine grapes will be declining, leading to the need for possible adaptation measures such as irrigation or misting of grape clusters to control temperature.

  • Existing water stress is the proportion of area suitable for viticulture with WSI >0.2 (25).

  • FII is the percentage of suitable viticulture area that meets the three criteria of suitability decline by 2050, projected decline in precipitation by 2050, and existing WSI >0.2.