Abrupt, 'irreversible' drop in global freshwater levels, Nasa study claims

Recent data from Nasa satellites have revealed that Earth's surface has lost freshwater abruptly since 2015. This major drop coincides with a 2014 to 2016 period of El Niño warming

Scientists using observations from NASA-German satellites have found evidence that the total amount of freshwater on earth dropped abruptly since May 2014, remaining low ever since. The study suggested that the shift could indicate that Earth's continents have entered a persistently drier phase. 

 

Our planet has lost 290 cubic miles (1,200 cubic km) of fresh water since 2015. This major drop coincides with a 2014 to 2016 period of El Niño warming. Typically, the freshwater regains after the climate oscillation ends, but recent satellite measurements up to 2023 reveal that the freshwater level is yet to recover, and may never recover. 

 

The team of researchers report that 13 of the world’s 30 most intense droughts observed by GRACE occurred since January 2015. The study also suspects that global warming could be the reason behind the decline in freshwater. 

 

This declining underground water supply is the result of the modern expansion of irrigated agriculture, farms and cities using fresh groundwater during drought. Rain and snow fail to replenish the need for freshwater that has been depleted. 

 

According to a UN report, the low level of water puts strain on farmers and communities, leading to famine, conflicts, poverty and disease risk when people turn to contaminated water sources. 

 

The decline in global level of freshwater declined with a drought in northern and central Brazil, which was then observed in Australasia, South America, North America, Europe, and Africa, according to study reports. 

 

Matthew Rodell, a hydrologist at NASA's Goddard Space Flight Center, said, "We don't think this is a coincidence, and it could be a harbinger of what's to come." 

 

Another study conducted by watercommission.org highlighted that the destructive land use and the mismanagement of water resources means that 3 billion people are facing "unprecedented stress" on their water system. 

 

NASA Goddard meteorologist Michael Bosilovich states that global warming holds more water vapour resulting in more extreme precipitation. The total annual and snowfall levels may not change dramatically, the long gap between intense precipitation events allows the soil to dry and become more compact, decreasing the water amount that the ground can absorb when it does rain.

 

Bosilovich noted that the level of water stayed low since the 2014-2016 El Niño, while more water was trapped in the atmosphere as water vapour. “Warming temperatures increase both the evaporation of water from the surface to the atmosphere, and the water-holding capacity of the atmosphere, increasing the frequency and intensity of drought conditions,” Bosilovich added.