Today is Tuesday, January 30, 2024.
Another important study published at Nature last January 24. About aquifers globally.
Trends and data analysis of in situ groundwater-level for 170,000 monitoring wells and 1,693 aquifer systems demonstrate widespread rapid water decline and only some cases of recovery.
As main conclusions, we quote the authors Jasechko, S., Seybold, H., Perrone, D. et al. exactly as reported.
"We show that rapid groundwater-level declines (>0.5 m year) are widespread in the twenty-first century, especially in dry regions with extensive croplands.
Critically, we also show that groundwater-level declines have accelerated over the past four decades in 30% of the world’s regional aquifers. This widespread acceleration in groundwater-level deepening highlights an urgent need for more effective measures to address groundwater depletion.
Our analysis also reveals specific cases in which depletion trends have reversed following policy changes, managed aquifer recharge and surface-water diversions, demonstrating the potential for depleted aquifer systems to recover".
There are also cases of rapidly rising groundwater levels, but they remain outnumbered by cases of rapidly deepening groundwater levels. According to the study, excessive groundwater withdrawals can cause:
groundwater levels to decline;
seawater intrusion;
land subsidence;
streamflow depletion;
and wells running dry.
In short, climatic trends and hydrogeologic conditions are not the only twenty-first century threats. They also include groundwater withdrawal rates, land uses and management approaches.
The critical scenario described above relates to countries that encompass approximately 75% of global groundwater withdrawals. It is also where a significant portion of the 8 billion earthlings currently live.
Should we expect an era of explicit water export? Like (rich) soil exports? Recall here something we heard last December 2023, during last COP-28 in Dubai: Middle East is importing containers of rich soil from other countries, for local production of e.g. fruits and vegetables. Recall here. By the way, the same post includes reference to "cloud seeding" and the impressive "Saudi Green Initiative".
In terms of implicit water exports - included in food and agriculture products - just think how much water is needed to produce one kilo of rice, potatoes, banana, beef or chocolate. Give a look in this interesting table, in another great article by Nature Education, from 2013. By the way, there is also a topic titled "Thirst of Arabia: Greening the desert" also worth reading. Together with our more recent post mentioned above.
You may also like to refer to the table "Water in Meat & Poultry" by USDA, United States Department of Agriculture, Food Safety and Inspection Service.
Click at the image below to read the complete "Rapid groundwater decline and some cases of recovery in aquifers globally" at Nature 625, 715–721 (2024).
Last but not least, like a "Carbon Footprint Calculator", you may like to try this interesting "Water Footprint Calculator".
As well as remembering US research into offshore aquifers, below the seabed "Scientists Map Huge Undersea Fresh-Water Aquifer Offshore U.S. Atlantic".
