Research ArticleSUSTAINABILITY

Four billion people facing severe water scarcity

See allHide authors and affiliations

Science Advances  12 Feb 2016:
Vol. 2, no. 2, e1500323
DOI: 10.1126/sciadv.1500323
  • Fig. 1 Quarterly averaged monthly blue water scarcity at 30 × 30 arc min resolution.

    Water scarcity at the grid cell level is defined as the ratio of the blue water footprint within the grid cell to the sum of the blue water generated within the cell and the blue water inflow from upstream cells. Period: 1996–2005.

  • Fig. 2 Annual average monthly blue water scarcity at 30 × 30 arc min resolution.

    Period: 1996–2005.

  • Fig. 3 The number of months per year in which blue water scarcity exceeds 1.0 at 30 × 30 arc min resolution.

    Period: 1996–2005.

  • Table 1 Number of people facing low, moderate, significant, and severe water scarcity during a given number of months per year, for the average year in the period 1996–2005.

    Number of
    months per
    year (n)
    Billions of people facing low, moderate, significant, and
    severe water scarcity during n months per year
    Billions of people
    facing moderate or
    worse water scarcity
    during at least n months
    per year
    Billions of people
    facing severe
    water scarcity
    during at least n
    months per year
    Low
    water
    scarcity
    Moderate
    water
    scarcity
    Significant
    water
    scarcity
    Severe water
    scarcity
    00.544.985.222.076.046.04
    10.120.810.660.314.263.97
    20.120.190.130.373.953.66
    30.350.050.030.373.553.28
    40.330.010.0010.593.152.91
    50.30000.552.562.32
    60.33000.272.091.78
    70.47000.211.761.50
    80.59000.291.461.30
    90.40000.301.131.01
    100.40000.120.780.71
    110.30000.090.660.59
    121.78000.500.540.50
    Total6.046.046.046.04

Supplementary Materials

  • Supplementary Materials

    This PDF file includes:

    • Supplementary Discussion
    • Fig. S1. Average monthly blue water scarcity at a spatial resolution of 30 × 30 arc min.
    • Table S1. Comparison of results between the current study and previous studies.

    Download PDF

    Files in this Data Supplement:

Navigate This Article