Earth’s water cycle is shifting dramatically and it’s not good news
As climate change worsens and extreme weather events become the norm of the day, a new study led by American space agency, Nasa, confirms that Earth’s water cycle is shifting in unprecedented ways.
The shift is largely attributed to human activities, including agriculture that could impact ecosystems in several parts of the world with major implications for people in these regions.
The water cycle ensures the continuous availability of fresh water, which is vital for the survival of all living organisms. Plants, animals, and humans rely on fresh water for drinking, food production, and ecosystems.
It continuously replenishes rivers, lakes, and underground aquifers through precipitation, ensuring a sustainable supply of freshwater for drinking, irrigation, and industrial uses, making it critical for the functionality of vital systems.
Sujay Kumar, a research scientist at Nasa’s Goddard Space Flight Center and co-author of the paper said, “We established with data assimilation that human intervention in the global water cycle is more significant than we thought.”
The findings published in the Proceedings of the National Academy of Sciences focused on three different kinds of shifts or changes in the cycle: first, a decrease in water in a groundwater reservoir; second, a change in seasonality, like the typical growing season starting earlier in the year, or earlier snowmelt; and third a change in extreme events, like “100-year floods” happening more frequently.
They gathered remote sensing data from 2003 to 2020 from several Nasa satellite sources. The assessment is based on nearly 20 years of satellite observations.
Augusto Getirana, a research scientist and another co-author of the study added that the satellite observations helped precisely simulate continental water fluxes and storages across the planet.
The new findings confirm that Earth system models used to simulate the future global water cycle should evolve to integrate the ongoing effects of human activities.
“We hope that this research will serve as a guide map for improving how we assess water resources variability and plan for sustainable resource management, especially in areas where these changes are most significant,” Wanshu Nie, lead author of the paper said.
