Many people know that over 70% of the Earth's surface is covered by water, which amounts to approximately 3.26 billion trillion gallons.

Yet, humanity still faces water scarcity issues. Why is that?

97.5% of the Earth's water is saltwater, leaving only 2.5% as freshwater.

Of this freshwater, nearly 70% is frozen in the ice caps of Antarctica and Greenland, with the remaining portion primarily inaccessible in deep underground aquifers or locked in soil moisture. Rivers, lakes, reservoirs, and shallow groundwater, which are more accessible water sources for human use, account for less than 1% of global freshwater, roughly 0.007% of all water on Earth.

The total annual precipitation on land is about 110 trillion cubic meters, but after accounting for atmospheric evaporation and water absorbed by plants, the world's river runoff amounts to about 42.7 trillion cubic meters. Based on the world's population in 1995, this equates to an average annual water availability of 7,300 cubic meters per person. However, due to the continuous increase in the world population, this average has decreased by 37% since 1970.

Examining world maps of rivers and lakes reveals a highly uneven distribution of freshwater across different regions of the world.

However, both developed and developing countries require significant amounts of water for commercial and personal use. It is estimated that agricultural water use alone accounts for 70% of the total available freshwater globally.

Below, we can examine the per capita water withdrawal trends over the past few decades for each country using the latest available data.

Many countries with high per capita water withdrawals are located in the arid desert regions of Central Asia, with Turkmenistan ranking first with a per capita annual water withdrawal of 5,753 cubic meters in 2005.

Countries like Turkmenistan and Guyana, with high water usage, primarily allocate most of their water for agricultural purposes. For example, it is estimated that 95% of Turkmenistan's available water resources are used for agriculture.

Developed countries such as Finland, New Zealand, and the United States also have per capita annual water withdrawals exceeding 1,000 cubic meters, but the purposes of water withdrawal in these countries are significantly different. For instance, in the United States, 41% of water withdrawals in 2015 were for thermoelectric power generation, while 37% were for irrigation and livestock. In Finland, 80% of water is used for industrial production.

Countries with lower per capita water withdrawals are mostly concentrated in Africa, including densely populated countries like Nigeria and Kenya, where per capita water withdrawals in 2015 and 2010 were approximately 75 cubic meters, respectively.

How can we protect water resources?

1. Mobilize society to change traditional water usage habits. Encourage water conservation and reuse practices throughout society.

2. Foster a culture of water conservation and raise awareness of water resource crises through various forms of education and awareness campaigns.

3. sustainably develop water resources to avoid resource depletion.

4. Improve water use efficiency and reduce wastage. Promote water reuse and employ economic incentives to encourage efficient water use.

5. Enforce strict supervision and management systems for water pollution prevention and control. Adhere to the principle of "polluter pays" and implement veto systems for environmental protection to facilitate the treatment of business wastewater, ultimately achieving comprehensive water resource utilization.

Let's unite in our efforts to protect and preserve this vital resource, securing a brighter tomorrow for generations to come.