Economically challenged and water scarce: identification of global populations most vulnerable to water crises

Figures & data

Table 1. Data used in this study

Parameter	Variable	Unit and Size	Source
GDP-PPP (0.5° × 0.5°)	GDP in 2020	USD billions per year	Murakami and Yamagata (2016)
Precipitation (0.01° × 0.01°)	Mean annual precipitation	mm/y	Karger et al. (2017)
Population (0.5° × 0.5°)	Population	capita per grid	Goldewijk, Beusen, Doelman, and Stehfest (2017)
Available freshwater (0.5° × 0.5°)	Total Runoff total (surface + subsurface)	kg/m^2/s	Hanasaki et al. (2018a)
Withdrawal rate (0.5° × 0.5°)	Net industrial water consumption	kg/m^2/s
	Net domestic water withdrawal
	Net agricultural water withdrawal

Figure 1. Histogram of population in terms of mean annual precipitation (mm/year).

Figure 2. Histogram of population in terms of available precipitation water (m3/capita/year).

Figure 3. Histogram of population in terms of annual runoff (mm/year).

Figure 4. Spatial distribution of available freshwater (m³/capita/year).

Figure 5. Histogram of population in terms of available freshwater (m³/capita/year).

Table 2. Distribution of population by water availability

Availability (m^3 per capita per year)	Description	Population distribution (%)
		Rainwater	Freshwater
<500	Extremely low	9.2	42.2
500–1000		12.3	13.7
1,000–2,000	Very low	20.2	13.6
2,000–5,000	Low	23.6	14.7
>5,000	Average	34.8	15.9

Figure 6. Histogram of population in terms of net total annual withdrawal (m³/capita/year).

Figure 7. Spatial distribution of water stress represented by withdrawal-to-available-water ratio (WWR).

Table 3. Distribution of population by water stress

Withdrawal-to-available-water ratio	Remarks	Population distribution (%)
			<0.1	No water stress	81.8
0.1–0.2	Low water stress	6.2
0.2–0.4	Moderate water stress	4.6
>0.4	High water stress	7.5

Figure 8. Histogram of population in terms of withdrawal-to-available-water ratio.

Figure 9. Scatter plot of water availability per capita and GDP-PPP per capita analyzed by 0.5° longitudinal and latitudinal grid boxes.

Figure 10. Scatter plot of water availability and GDP-PPP per capita by country-level analysis.

Figure 11. Longitudinal and latitudinal grid boxes (0.5° × 0.5°) showing areas below the threshold line of both economically poor and water-scarce.

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