Announcing the Water Scarcity Clock: World Data Lab takes on SDG 6
70% of the Earth’s surface consists of water but 97.5% of it is salt water. Nearly two percent is frozen at the poles in glaciers and in permafrost. That leaves only 0.75% of the Earth’s water for human use and only 0.3% is actually on the surface in the form of rivers and lakes. According to the The Economist, 59% of humanity’s water needs are drawn from this small source. Future stress on the world’s water supply rests mainly on three factors: population growth, prosperity, and climate change.
In order to address the issue of water scarcity, World Data Lab is developing the Water Scarcity Clock (WSC) which will allow everyone to see the number of people in the world suffering from water scarcity while giving users the ability to explore the affected parts of the world. The tool is being developed with the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) and the International Institute for Applied Systems Analysis (IIASA) in order to provide decision-makers with granular and actionable information so that the world can fulfill SDG 6 (ensure availability and sustainable management of water and sanitation for all).
Users will be able to use the Water Scarcity Clock to compare water availability and water use between countries. Water availability numbers will also be able to be adjusted to see which percentage of the population lives in areas with a water availability of less than 500 m3, 1,000 m3, and 1,700 m3 per capita. According to the Falkenmark Water Stress Indicator, a country or region is said to experience “water stress” when annual water supplies drop below 1,700 m3 per person per year. At levels between 1,000-1,700 m3 per person per year, periodic or limited water shortages can be expected. When water supplies drop below 1,000 m3 per person per year, the country faces water scarcity.
Who's it for?
WSC is an early warning tool for every international organization and national department who is trying to achieve SDG 6 by 2030. Water stress is an issue in 22 countries, mostly in North Africa and Western, Central, and South Asia. In these areas, the water stress level is above 70% indicating the strong probability of future water scarcity.
However, it is important to note that future water scarcity or water stress will not only affect less developed parts of the world. It is already an issue in industrialized countries such as Australia and Cyprus. The share of these countries’ population affected by water scarcity will rise from 26.5% and 21.3% in 2016 to 46% and 61.5% by 2030, respectively.
Preliminary analysis from the beta version of the Water Scarcity Clock showed that in 2006, almost 2.5 billion people lived with less than 1,700 m3 of water per capita, around 37% of the world population. By 2016, when the SDGs officially started, this number increased to 2.9 billion (39.6% of world population) and is forecasted to reach 3.5 billion people by 2030 (42.1% of the world population).
The model for WSC is based on water data from 0.5 x 0.5 degree sized grids. Each grid contains the population and overall water availability for that area. Based on this data we calculate the average water availability per capita per grid. The grids are then summed up in order to calculate the water availability for an entire country.
The water data is based on 3 Global Hydrological and 5 General Circulation models. Combining these together, WSC produces an overall average providing the best estimate of current and future water availability around the world to date. However, it is important to note that WSC forecasts are based on the latest data available but are subject to substantial uncertainties.