Report: Water Cycle in Crisis

The water cycle is among Earth’s most vital processes that support and sustain life. But the cycle is at risk of changing for the first time in human history. That’s according to a new report from the Global Commission on the Economics of Water (GCEW). 

The water cycle describes the circuit moisture travels as it moves through an ecosystem. As water is exposed to heat from the sun’s rays, it turns from liquid to vapor. That vapor enters the air. It is then carried upward until it condenses. Once it does, it falls in the form of precipitation (think rain or snow). The process routes water to forests and fields. It's also vital for the upkeep of rivers, lakes, and streams. It refills reservoirs, too.

So-called “blue water” is liquid water that exists in the environment. The study found that many sources of blue water are under duress. But the study found the main driver of the change is humans’ impact on “green water.” That’s all the moisture held and released by plants. Green water is estimated to account for nearly 50% of all rainfall. As humans have cut down forests and climate change raises wildfire risk, many of the plants that would contribute green water to the water cycle have been destroyed.  

GCEW’s report does offer a pathway to lessen harmful effects like prolonged droughts and food scarcity brought on by a change in the water cycle. Ngozi Okonjo-Iweala is director general of the World Trade Organization. She told CNN that global teamwork is key. She said it'll give people a chance to better protect water as a natural resource.

Reflect: What are some ways we can help protect the environment and make sure natural resources last for future generations?