NASA satellites reveal an abrupt drop in freshwater levels around the world

NASA Satellites Reveal an Abrupt drop in Freshwater levels around the World

NASA-German satellite observations show that Earth’s total amount of freshwater dropped abruptly starting in May 2014 and has remained low ever since.

Several researchers stated in Surveys in Geophysics that the shift might indicate Earth’s continents have become persistently drier.

A study by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, showed that the average amount of freshwater stored on land from 2015 through 2023 was 290 cubic miles (1,200 cubic km) lower than average levels from 2002 through 2014. Almost twice as much water has been lost from Lake Erie.”

In drought conditions, farms and cities must rely more heavily on groundwater, due to the expansion of irrigated agriculture.

In addition to depleting freshwater supplies, rain and snow fail to replenish them, so more groundwater has to be pumped.

Farmers and communities suffer from a lack of water, potentially causing famine, conflict, poverty, and an increased risk of disease if they use contaminated water sources, says a 2024 UN water stress report.

Gravitational fluctuations on monthly scales are measured by GRACE satellites, which reveal changes in water mass. GRACE satellites flew from March 2002 through October 2017. GRACE-Follow On (GRACE-FO) satellites launched in May 2018.

Several major droughts followed widespread droughts across Australasia, South America, North America, Europe, and Africa shortly after the massive drought in northern and central Brazil.

Ocean temperatures in the tropical Pacific, culminating in the strongest El Nio event since 1950, led to shifts in atmospheric jet streams, altering global weather patterns.

Global freshwater levels remained low after El Nio subsided. Interestingly, 13 of the 30 most intense droughts observed by GRACE since January 2015 have occurred since January 2015. Global warming may contribute to the enduring freshwater crisis, Rodell and colleagues suspect.

More water vapor means more extreme precipitation thanks to global warming, said NASA meteorologist Michael Bosilovich.

Rainfall and snowfall levels may not change dramatically, but long intervals between heavy rains allow the soil to dry and compact. Water is less easily absorbed when it rains because of that.

Extreme precipitation leads to water running off instead of soaking into and replenishing groundwater stores, Bosilovich said. Freshwater levels across the globe have remained low since 2014–2016 El Nio, while more water remains trapped in the atmosphere.

Temperature increases increase evaporation and water-holding capacity of the atmosphere, and increase drought frequency and intensity.”

Freshwater levels seem to have dropped abruptly due to global warming, but it can be hard to definitively link the two, said Susanna Werth, a hydrologist at Virginia Tech.

Climate predictions are uncertain. Every measurement and model has an error.

Freshwater levels may rebound, hold steady, or decline, depending on what happens. “Considering the abrupt freshwater declines coincided with the 9 warmest years in the modern temperature record, we don’t think this was a coincidence,” Rodell said.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *