For Openers: News and Notes at Press Time
by Greg Ettling
January 3, 2012
Drilling Project in the Dead Sea Warns of Climate Change
An international team of scientists drilling deep under the bed of the Dead Sea
has found evidence that the sea may have dried up during a past warm period
similar to predicted scenarios for climate change in coming decades. University of Minnesota College of Science and
Engineering professor of earth sciences Emi Ito is one of the researchers on
the team.
With nations in the volatile region already running short on water, the finding
could be a warning of worse shortages to come, the researchers say. The lakebed
cores, which contain about 200,000 years of environmental history – the
Mideast’s longest archive – also record earthquakes and other natural
phenomena, and may shed light on human development and current seismic
risks.
The Dead Sea is the world’s lowest-lying place on land, with shores some 1,400
feet below sea level, and salty waters going down another 1,200 feet. Fed by
the Jordan River, it has shrunk rapidly over past decades, as water is pulled
for farming and other uses.
Near the sea’s center, under 900 feet of water, the team penetrated some 750
feet of muddy sediment, then hit a layer of nearly pure pebbles, underlain by
some 120 feet of salt. The salt suggests to them that the lake dried quickly,
precipitating out solids. The pebbles appear to be a beach – given their
position near the middle, a signal that the sea more or less disappeared.
Research by others already has shown that the sea has fluctuated, but this is
the first time anyone has found that it actually
disappeared.
The cores have not yet been precisely dated, but the researchers have
correlated some layers with isotopes found in Mideast cave deposits, and
believe the total drying took place around 125,000 years ago – the height of a
warm period between the two most recent ice ages, when the Mideast already is
known to have been not only warmer, but drier, than today. Climate projections
say that if the world keeps warming as it is now, the Mideast could return to
this more arid state within decades.
Reports by the United Nations and other bodies have cited water as a potential
spark for future Mideast conflicts. In the
past, the governments of Egypt and Jordan have said that they would never go to
war again against Israel – except over water.
“The Dead Sea has witnessed so much of human history from the migration of
early humans out of Africa, habitation by early Stone Age people all the way to
the Near East politics of today,” says Ito. “To think that we, the humans, are
helping it perhaps dry up, is very sobering.”
Ito says the Dead Sea water level has been
going down by three feet to five feet each year, due to a combination of dry
climate of the region and human activity. Jordan River’s water is heavily used
for irrigation and little is left to flow into the Dead
Sea. If the previous warm period before the last ice age is any
guide, the Near East is going to become drier and drier under warming
climate.
The Dead Sea’s basin is a plate boundary like the San Andreas Fault in
California, and the cores also contain a detailed log of past earthquakes
there. When quakes occur, typically flat layers of sediment are twisted into
convoluted shapes. With precise dating, these should form a history from
ancient times to the present, and perhaps give a better picture of future risks
faced in the region. It could help answer longstanding questions. For instance,
some say the Biblical overthrow of the walls of Jericho was performed by an earthquake – but
whether such a quake took place, and when, has remained controversial. The
research team now is in the process of doing more precise
dating.
The drilling, some 10 years in the making, was done under the auspices of the
International Continental Scientific Drilling Program (ICDP), which sponsored
the project and covered much of the cost.
The Latest from EPA on Hydrofracturing: Blame for Pollution
The U.S. Environmental Protection Agency (EPA) recently announced for the first
time that hydrofracturing may be to blame for causing ground water
pollution.
The agency released a draft analysis of data from its Pavillion, Wyo., ground
water investigation. At the request of Pavillion residents, EPA began
investigating water-quality concerns in private drinking water wells three
years ago. Since that time, in conjunction with the state of Wyoming, the local
community, and the owner of the gas field, Encana, EPA has been working to
assess ground water quality and identify potential sources of
contamination.
EPA constructed two deep monitoring wells to sample water in the aquifer. The
draft report indicates that ground water in the aquifer contains compounds
likely associated with gas production practices, including hydraulic
fracturing. EPA also re-tested private and public drinking water wells in the
community. The samples were consistent with chemicals identified in earlier EPA
results released in 2010, and generally are below established health and safety
standards. To ensure a transparent and rigorous analysis, EPA is releasing these
findings for public comment and will submit them to an independent scientific
review panel. The draft findings announced are specific to Pavillion, where the
fracturing is taking place in and below the drinking water aquifer and in close
proximity to drinking water wells – production conditions different from those
in many other areas of the country.
Natural gas plays a key role in our nation’s clean energy future and the Obama
administration is committed to ensuring that the development of this vital
resource occurs safely and responsibly. At the direction of Congress, and
separate from this ground water investigation, EPA has begun a national study
on the potential impacts of hydraulic fracturing on drinking water resources.
EPA’s analysis of samples taken from the agency’s deep monitoring wells in the
aquifer indicates detection of synthetic chemicals, like glycols and alcohols
consistent with gas production and hydraulic fracturing fluids, benzene
concentrations well above Safe Drinking Water Act standards and high methane
levels. Given the area’s complex geology and the proximity of drinking water
wells to ground water contamination, EPA is concerned about the movement of
contaminants within the aquifer and the safety of drinking water wells over
time.
EPA also updated its sampling of Pavillion area drinking water wells. Chemicals
detected in the most recent samples are consistent with those identified in
earlier EPA samples and include methane, other petroleum hydrocarbons and other
chemical compounds. The presence of these compounds is consistent with
migration from areas of gas production. Detections in drinking water wells are
generally below established health and safety standards.
The draft finding could have significant implications while states try to
determine how to regulate the process.
ND
|