Why are there often water shortages on the earth?

The earth's water reserves are very large, about 14 billion cubic meters, of which 94% are distributed in the ocean, which cannot be directly used for human life and production. According to the United Nations in 1977, the world's freshwater reserves were only 100 million cubic meters. Although freshwater resources are limited, they are still quite numerous, and the per capita share is as high as one million cubic meters.

So why are there still water shortages in some places? It turns out that freshwater resources are extremely unevenly distributed throughout the world. In watery areas, such as East and South Asia, large amounts of rainwater are converted into surface runoff and flow into the sea. In arid desert areas, such as Ethiopia, South Africa, Sudan, Kenya and other regions, water shortage is severe.

In the case of China, Inner Mongolia and the northwest are very arid regions, and the Huang-Huai-Hai region is also severely short of water resources. Coupled with the development of industrial and agricultural production in the world, water consumption has increased dramatically; Cities and urban populations continue to grow, and the need for drinking water has increased dramatically, resulting in water shortages in 60 per cent of the world, and even water shortages in many countries.

There is abundant water on the earth, and it is widely distributed, and about 3 4 of the world's area is covered with water, so the earth is called the "planet of water". The earth's water reserves are also very large, about 14 billion cubic meters, of which 94% are distributed in the ocean, which cannot be directly used for human life and production. According to the United Nations in 1977, the world's freshwater reserves are only 100 million cubic meters, and how many of these freshwater resources can be used by human beings?

Statistics show that the total amount of fresh water that is difficult to use, such as snow cover from glaciers in the north and south poles and alpine mountains, ice at the bottom of permafrost and deep groundwater, accounts for the total amount of fresh water, so only the fresh water that accounts for the total amount of fresh water is the freshwater resources that can be used by human beings. They account for only one of the world's total water reserves. This shows that the freshwater resources that can be used by human beings are indeed limited, not inexhaustible.

Although freshwater resources are limited, they are still quite large in absolute terms, with millions of cubic meters per capita. So why are there still water shortages in some places? It turns out that the geographical distribution of freshwater resources around the world is extremely uneven.

In watery areas, such as East Asia and South Asia, a large amount of rainwater is converted into surface runoff and flows back to the sea; Arid desert areas, such as Ethiopia, Sudan, South Africa, Kenya, etc., are extremely water-scarce. As far as China is concerned, Inner Mongolia and the northwest are extremely arid areas, and the Huang-Huai-Hai region is also a very water-scarce region. Coupled with the development of industrial and agricultural production in the world, water consumption has increased dramatically; The growing population of cities and cities has led to a dramatic increase in drinking water, resulting in inadequate water supply in 60 per cent of the world's regions and water shortages in many countries.

Of the world's 5.3 billion people, 3.4 billion have an average daily access to only 50 litres of water.

Nowadays, there is a water shortage everywhere in the world, and water scarcity has become a worldwide problem, and 80 countries have suffered from severe water shortages.

In countries such as Ethiopia, more than 1 million people have died of starvation and millions more have been malnourished in the past 10 years due to years of drought and civil war.