Global water resources distribution

Global water resources distribution

The total water reserves of the 10 countries with the richest water resources account for 65% of the world's total water supply, while severe water shortages affect 80 countries, home to 40% of the global population. The global demand for water resources is growing at an alarming rate, while the amount of water available for consumption is decreasing sharply.

Water resources are facing a serious crisis, and some worry that the last drop of water on Earth will be human tears.

Water is a precious resource essential for human survival and development.
An ancient saying goes, "Three mountains, six rivers, and one field." Although the Earth's total water volume is approximately 1.4 billion cubic kilometers, about 97.5% of it consists of saltwater, primarily found in oceans and saltwater lakes.
Freshwater resources make up only about 2.5% of the total water supply, with most of it locked in glaciers, permanent snow caps, and permafrost at the poles.
The truly usable portion consists of rivers, lakes, and shallow groundwater, which account for just 30.3% of global freshwater resources and approximately 0.75% of the Earth's total water volume.

In the 20th century, the growth rate of global water consumption was more than twice that of the population. The rapid increase in global freshwater consumption has exacerbated water resource challenges, making water-related issues more prominent. As a result, the strategic importance of water resources has become increasingly evident.

It is predicted that in the 21st century, water will become a crucial factor in determining a nation's wealth. Its value may even rival the significance of oil to humanity in the early 20th century.

The distribution of water resources in the world today is very uneven.

From the perspective of geography and population distribution, nine countries-Canada, the United States, Brazil, and Colombia in the Americas; Russia, China, and India in Eurasia; the Democratic Republic of the Congo in Africa; and Indonesia in the Indian and Pacific Oceans-hold 60% of the world's freshwater resources.

However, 80 countries and regions, home to 40% of the global population (approximately 1.5 billion people), are experiencing severe freshwater shortages. Among them, 26 countries, with a combined population of about 300 million, are in a state of extreme water scarcity.

From the perspective of geographical environment and natural endowment, except for Europe, which benefits from a favorable geographical environment and relatively abundant water resources, all other continents have regions experiencing varying degrees of severe water shortages.

The most pronounced shortages occur in the landlocked countries of sub-Saharan Africa, where nearly every nation faces serious water scarcity. Similar challenges also exist in parts of Asia.

From the perspective of historical development and population growth, per capita water consumption has always been increasing. For example, in BC, per capita water consumption was about 12 liters per day, in the Middle Ages, per capita water consumption increased to 20-40 liters, and in the 18th century, it increased to 60 liters. At present, some large cities in developed countries consume 500 liters of water per day.

In developing countries, the demand for water is also increasing. For example, in my country, urban water consumption has doubled several times in the past 20 years.

The trend of history is irreversible, the endowment differences of natural geography cannot be changed, and the tense situation of water supply and demand can only become increasingly severe.

First and foremost, the significance of water resources to humanity lies not only in quantity but also in quality.

Currently, nearly 1.1 billion people worldwide lack access to clean drinking water. Each year, approximately 4 million people die from illnesses caused by contaminated water, with children under the age of five accounting for nearly 11% of these deaths. These issues are especially severe in developing countries.

Secondly, the global demand for water resources will continue to rise in the future. Addressing the growing demand while managing limited resources presents another major challenge we must confront.

On the one hand, for many developing countries, the key to solving global poverty lies in the development of agriculture. Since 1950, advancements in agriculture have played a crucial role in reducing poverty and stabilizing food prices.

Currently, more than 70% of global freshwater demand is allocated to agriculture. However, to achieve the United Nations Millennium Development Goal of halving the world's poor population (using 1990 as the base year), agricultural water use would need to at least double.

On the other hand, more than 2 billion people worldwide live in arid regions, which also contain 41% of the world's arable land. Nearly one-third of the global population is affected by water shortages. The long-term ability of water resources to sustain human development has become an increasing concern.

Thirdly, the rapid expansion of major cities has led to a growing demand for water resources, with impacts that are difficult to quantify. Since the early 20th century, the number of major cities with populations exceeding one million has risen from 16 to 532, including many megacities with over 10 million residents.

At present, we still lack a comprehensive and scientific assessment of the impact of these large and megacities on water resources and climate change. Furthermore, we have yet to propose feasible solutions or implement effective measures to proactively address this unprecedented challenge.

To address these challenges, we can take measures from the following two aspects:

On the one hand, countries must strengthen the management and regulation of water resources. This includes enhancing international cooperation and coordination, reducing water pipeline losses, promoting efficient water conservation, and advocating for the recycling and reuse of water resources.

On the other hand, when it comes to agricultural water use, efforts must focus on improving water efficiency. Agriculture accounts for two-thirds of global water consumption. To ensure sustainable development while maintaining crop yields, the adoption of scientific farming practices, efficient water use, and the adaptation of irrigated land to future water efficiency needs are essential for human survival and long-term sustainability.