The water cycle is essential to various systems, including natural, like climate, and social, such as agriculture. This is why the latest report from the Global Commission on the Economics of Water (GCEW) has raised significant concerns.
The GCEW report. The GCEW recently released a report titled “The Economics of Water: Valuing the Hydrological Cycle as a Global Common Good.” Its findings are concerning. The study highlights that human activities are disrupting the hydrological cycle, pushing it “out of balance.” The potential consequences of this disruption could be very serious.
Water cycle. Most people are familiar with simple models of the water cycle. However, like any model, these representations oversimplify a complex system with numerous interactions. Additionally, these interactions are changing due to human intervention.
The water cycle involves the evaporation of seawater, its condensation in the atmosphere to create rain, and the roles played by rivers and plants. This natural process has been repeating itself for hundreds of millions of years. However, today, the cycle is more complex, involving reservoirs, sewage systems, wastewater, desalination plants, drainage systems, agricultural and industrial uses, and wastewater treatment plants.
The GCEW report explores this complexity by distinguishing between “blue water” and “green water.” “Blue water” refers to bodies of water such as lakes, rivers, and aquifers, while “green water” refers to moisture stored in the soil and within plants.
Green waters. Green waters are often overlooked, as noted in the GCEW report. This phase of the water cycle is essential to precipitation. The water reaches plants and soil, where plants absorb the moisture they need and store it to carry out their vital functions. Both the water stored in plants and the moisture in the soil can evaporate, returning water to the atmosphere and restarting the cycle.
Neglecting this aspect of the water cycle can lead to underestimating the consequences of altering ecosystems, such as changes in land use, deforestation, and urbanization. For example, deforestation in one area can result in changes in rainfall patterns in another region.
A model of the water cycle distinguishing “blue” and “green” waters. | Image: Global Commission on the Economics of Water
Serious consequences. Disruptions in the water cycle can have significant impacts on both nature and society. The GCEW report addresses important issues, such as the cost of inaction and how changes in the hydrological cycle can affect the economy.
Sectors like food production, industry, power generation, hygiene systems, and data centers rely heavily on water. These changes could result in potential economic growth falling 8-15% below expectations by 2050.
New framework. The pressure on water systems is increasing. Water consumption is rising while aquifers are being depleted and degraded in many regions. In its report, the GCEW proposes a new framework for valuing water aimed at promoting better management of this essential resource.
GCEW. The GCEW is an independent organization sponsored by the government of the Netherlands and the Organization for Economic Co-operation and Development. Its primary objective is to “redefine the way we value and govern water for the common good.”
The recent report represents the final outcome of the GCEW’s work in 2022. The framework established in it serves as a guide for stakeholders to adapt their decision-making processes to focus on maintaining the global hydrological system. Changes in natural systems are becoming increasingly evident, but acknowledging these changes may not be sufficient to transition from theoretical models to actionable outcomes.
Image | Wesley Tingey
View 0 comments