SAN FRANCISCO -- Human consumption could deplete groundwater in parts of India, southern Europe and the U.S. in the coming decades, according to new research presented here today.
New modeling of the world's groundwater levels finds aquifers -- the soil or porous rocks that hold groundwater -- in the Upper Ganges Basin area of India, southern Spain and Italy could be depleted between 2040 and 2060.
In the U.S., aquifers in California's Central Valley, Tulare Basin and southern San Joaquin Valley, could be depleted within the 2030s. Aquifers in the southern High Plains, which supply groundwater to parts of Texas, Oklahoma and New Mexico, could reach their limits between the 2050s and 2070s, according to the new research.
By 2050, as many as 1.8 billion people could live in areas where groundwater levels are fully or nearly depleted because of excessive pumping of groundwater for drinking and agriculture, according to Inge de Graaf, a hydrologist at the Colorado School of Mines in Golden, Colorado.
"While many aquifers remain productive, economically exploitable groundwater is already unattainable or will become so in the near future, especially in intensively irrigated areas in the drier regions of the world," said de Graaf, who will present the results of her new research today at the 2016 American Geophysical Union Fall Meeting.
Knowing the limits of groundwater resources is imperative, as billions of gallons of groundwater are used daily for agriculture and drinking water worldwide, said de Graaf.
Previous studies used satellite data to show that several of the world's largest aquifers were nearing depletion. But this method can't be used to measure aquifer depletion on a smaller, regional scale, according to de Graaf.
In the new research, de Graaf and colleagues from Utrecht University in the Netherlands used new data on aquifer structure, water withdrawals, and interactions between groundwater and surrounding water to simulate groundwater depletion and recovery on a regional scale.
The research team used their model to forecast when and where aquifers around the world may reach their limits, or when water levels drop below the reach of modern pumps. Limits were considered "exceeded" when groundwater levels dropped below the pumping threshold for two consecutive years.
The new study finds heavily irrigated regions in drier climates, such as the U.S. High Plains, the Indus and Ganges basins, and portions of Argentina and Australia, face the greatest threat of depletion.
Although the new study estimates the limits of global groundwater on a regional scale, scientists still lack complete data about aquifer structure and storage capacity to say exactly how much groundwater remains in individual aquifers, she said.
"We don't know how much water there is, how fast we're depleting aquifers, or how long we can use this resource before devastating effects take place, like drying up of wells or rivers," de Graaf said.
Media Q&A and presentation information
The researcher, Inge de Graaf, will be available to answer questions from members of the news media during a media Q&A from 8:30 - 9:00 a.m. PT today in the Press Conference Room, Moscone West, Room 3000. The media availability will also be streamed live over the web. Information about how to stream press conferences can be found here.
The researchers will present a poster about their work on Thursday, 15 December 2016 at the AGU Fall Meeting.
Poster Title: Limits to global groundwater consumption
Session: GC43C: Global and Regional Water-Food-Energy Security under Changing Environments III Posters
Date: Thursday, 15 December 2016 Time: 1:40 - 6:00 p.m. Abstract number: GC43C-1188 Location: Moscone South, Poster Hall
Contact information for the researcher: Inge de Graaf: firstname.lastname@example.org, +1 (720) 476-1946
2. Today's press events
8:30 a.m. - The future of the world's groundwater resources (Media Q&A)
9:00 a.m. - First results from Axial Seamount, an active underwater volcano
10:30 a.m. - Dawn science update
11:30 a.m. - Explaining extreme events in 2015 from a climate perspective
1:45 p.m. - Marcia McNutt (Media Availability)
All Fall Meeting press events will be streamed live on the AGU press events webpage and archived on AGU's YouTube channel.
3. Noteworthy sessions happening today
- Marcia McNutt, 22nd President of the National Academy of Sciences, will deliver the Union Agency Lecture from 12:30 - 1:30 p.m. in Moscone North, Hall E. Registered journalists who are interested in attending should meet an AGU staff member at the entrance to the lecture hall 30 minutes prior to the start of the talk. The lecture will be streamed live in the Press Conference Room, Moscone West, Room 3000 and on AGU On-Demand. A media availability will be held immediately following this session in the press conference room, Moscone West, Room 3000.
4. Press networking events happening today Members of the media will be able to meet and mingle with colleagues at several events throughout the week. Here is what's happening today:
JOURNALISM AWARDS RECEPTION
We invite you to join your Press Room colleagues to honor and celebrate AGU's most recent journalism award winners during an informal reception.
We will recognize the outstanding reporting and writing of 2016 Walter Sullivan Award for Excellence in Science Journalism-Features winner Lizzie Wade and the 2016 David Perlman Award for Excellence in Science Journalism-News winner Alexandra Witze.
The reception will take place in the Press Room, Moscone West, room 3001A, from 5:00 - 6:30 p.m.
5. Potentially newsworthy presentations happening today
- Redirecting seismic waves with metamaterials and sub-wavelength scatterers for protection of critical infrastructure
10:20 - 10:35 A.M., Moscone South, Room 303, Session S42B
- Sustainable milk and meat production while reducing methane emissions from livestock enteric fermentation
1:40 - 6:00 P.M., Moscone South, Poster Hall, Session GC43A
- Late-Breaking Session: The 24 August 2016 Central Italy Earthquake
1:40 - 6:00 P.M., Moscone South, Poster Hall, Session S43F
- Late-Breaking Session: 3 September 2016 M5.8 Pawnee Earthquake, Oklahoma
4:00 - 6:00 P.M., Moscone South, Room 309, Session S44C
- AGU journal editors recommend these sessions happening today and tomorrow.
6. Online media resources
For journalists: During the Fall Meeting, journalists can find many resources online in the Virtual Press Room in the Media Center on the Fall Meeting website. These resources include press releases, press conference materials and other information. Videos of press conferences will be added to the Virtual Press Room during the meeting for easy online access.
For public information officers: PIOs are now able to share press releases and other materials in the Virtual Press Room by directly uploading them via the Press Item Uploader. PIOs can upload press releases, tip sheets and press conference materials to the Virtual Press Room at any time before or during the meeting, including uploading items in advance and scheduling them to post during the meeting.
The AGU press office is offering two new online tools to connect reporters with scientific experts at the 2016 Fall Meeting. The Find an Expert tool allows public information officers to list scientific experts who are available to be interviewed by reporters at the meeting. The Request an Expert tool allows reporters to send requests for experts directly to PIOs.
More information about these tools can be found in the Fall Meeting Media Center.
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