2013 February 12. NASA Satellite Data Find Freshwater Losses in Middle East. NASA RELEASE 13-049. Excerpt: A new study using data from a pair of gravity-measuring NASA satellites finds that large parts of the arid Middle East region lost freshwater reserves rapidly during the past decade. ...during a seven-year period beginning in 2003, parts of Turkey, Syria, Iraq and Iran along the Tigris and Euphrates river basins lost 117 million acre feet (144 cubic kilometers) of its total stored freshwater. That is almost the amount of water in the Dead Sea. The researchers attribute about 60 percent of the loss to pumping of groundwater from underground reservoirs. ...NASA's twin Gravity Recovery and Climate Experiment (GRACE) satellites, are essential. GRACE is providing a global picture of water storage trends and is invaluable when hydrologic observations are not routinely collected or shared beyond political boundaries. "GRACE data show an alarming rate of decrease in total water storage in the Tigris and Euphrates river basins, which currently have the second fastest rate of groundwater storage loss on Earth, after India," said Jay Famiglietti, principle investigator of the study and a hydrologist and professor at UC Irvine. "The rate was especially striking after the 2007 drought. Meanwhile, demand for freshwater continues to rise, and the region does not coordinate its water management because of different interpretations of international laws." ...The team calculated about one-fifth of the observed water losses resulted from soil drying up and snowpack shrinking, partly in response to the 2007 drought. Loss of surface water from lakes and reservoirs accounted for about another fifth of the losses. The majority of the water lost ...was due to reductions in groundwater. ..."The Middle East just does not have that much water to begin with, and it's a part of the world that will be experiencing less rainfall with climate change," said Famiglietti. "Those dry areas are getting dryer. ...Study co-author Matt Rodell of Goddard added it is important to remember groundwater is being extracted unsustainably in parts of the United States, as well. "Groundwater is like your savings account," Rodell said. "It's okay to draw it down when you need it, but if it's not replenished, eventually it will be gone."....
2010 October 19. VIDEO: Protected areas in Kuwait and their potential long-term role in adaptation to climate change. Rio Conventions' Pavilion. Video Description: Dr. Samira Omar Asem, whose work studying the desert ecosystem of Kuwait following the 1990-1991 Iraq war is featured in Ecosystem Change chapter 3, presents more recent research on the Sabah Al Ahmad Nature Reserve.
2010 July 17. After Oil Spills, Hidden Damage Can Last For Years. By Justin Gillis and Leslie Kaufman, The New York Times.Excerpt:
Only 20 years ago, the conventional wisdom was that oil spills did
almost all their damage in the first weeks, as fresh oil loaded with
toxic substances hit wildlife and marsh grasses, washed onto beaches
and killed fish and turtles in the deep sea.
…But disasters like the Valdez in 1989, the Ixtoc 1 in Mexico in 1979,
the Amoco Cadiz in France in 1978 and two Cape Cod spills, including
the Bouchard 65 barge in 1974 — all studied over decades with the
improved techniques of modern chemistry and biology — have allowed
scientists to paint a more complex portrait of what happens after a
…[E]ven before the spill, the land was under enormous environmental
stress, largely due to human activity. Dams on the Mississippi River
and its tributaries have slowed the flow of sediment to the marshes,
and global warming has caused sea level to rise.
…Oil spills produce a powerful impulse to clean up the oil and restore
as much of the environment as possible. But that impulse can itself be
a source of destruction.
…The lesson, scientists say, is not that people should never try to
clean up an oil spill. It is possible to do too little as well as too
much. But the calculation of how much to do is tricky, demanding deep
scientific understanding of an area’s ecology. Applying supposed common
sense has repeatedly led to mistakes.
…Already in Louisiana, battles have erupted between the Army Corps of
Engineers and local residents, led by Gov. Bobby Jindal, over proposals
to build sand and rock barriers to block the oil from coming into the
marshes. The corps has been cautious on approval permits and recently
rejected a plan to build a rock barrier outside Barataria Bay, arguing
that such structures would change water-flow patterns to the possible
detriment of the marsh ecology.
2009 November 5. Climate Change, Nitrogen Loss Threaten Plant Life in Arid Desert Soils. NSF Release 09-218. Excerpt:
...As Earth's climate warms, arid soils lose more nitrogen, which could
lead to deserts with even less plant life than they sustain today.
Available nitrogen is second only to water as the biggest constraint to
biological activity in arid ecosystems, but ecologists have struggled
to understand the balance of the input and output of nitrogen in
deserts. For the first time, however, researchers have discovered a
mechanism that balances the nitrogen budget in deserts: Higher
temperatures cause nitrogen to escape as gas from desert soils.
...In the past, researchers focused on biological mechanisms in which
soil microbes near the surface produce nitrogen gas that dissipates
into the air, but ecologists Jed Sparks and Carmody ("Carrie")
McCalley, both at Cornell University and co-authors of the paper, found
that non-biological processes are playing a bigger role in nitrogen
losses from soil to air.
"This is a way that nitrogen is lost from an ecosystem that people have
never accounted for before," said Sparks. "It allows us to finally
understand the dynamics of nitrogen in arid systems."
...Further temperature increases and shifting precipitation patterns
due to climate change may lead to more nitrogen losses in arid
ecosystems, making their soils even more infertile and unable to
support most plant life, according to McCalley. Although some climate
models predict more summer rainfall for desert areas, the water, when
combined with heat, would greatly increase nitrogen losses, she said.
"We're on a trajectory where plant life in arid ecosystems could cease to do well," said McCalley....
2007 June 28. Likely Spread of Deserts to Fertile Land Requires Quick Response, U.N. Report Says. The New York Times. By Elisabeth Rosenthal. Excerpt:
Enough fertile land could turn into desert within the next generation
to create an ''environmental crisis of global proportions,''
large-scale migrations and political instability in parts of Africa and
Central Asia unless current trends are quickly stemmed, a new United
Nations report concludes. ''The costs of desertification are large,''
2007 January 3. Defining Desertification. By Holli Riebeek. NASA Earth Observatory. [This
article gives some insight into the origins and significance of the
development of NDVI (Normalized Difference Vegetation Index) which the
GSS Interpreting Digital Images software helps students to understand.
Botswana, 1984. Cattle roam over grasslands at the edge of the Kalahari
Desert. ...A full 77 percent of the country's 576,000 square kilometers
is already used for grazing, but even this isn't enough to support the
cattle. The grasslands are prone to drought, and the government is
forced to import food for them. British biogeographer Stephen Prince is
among the scientists that the United Nations Food and Agriculture
Organization has asked to assess the health of the rangelands. How is
drought impacting the land? Is overgrazing occurring? ...Conditions
could vary widely; healthy vegetation could be growing meters away from
barren land. "You couldn't measure vegetation change over the entire
country with 50 data points." ...Prince stopped by the house of a
colleague, John Townshend. ... from NASA Goddard Space Flight
Center...remote-sensing ecologist Compton Tucker had developed a new
scale, or index, of global vegetation based on satellite data. ...the
index could show how much photosynthesis was happening in every
8-by-8-kilometer patch of ground. Displayed as a map, the index
revealed the productivity of the grazing land over a broad area over
successive 15-day periods. ..."It blew me away that we could see a
complete continent at frequent time intervals," Prince says. "It was a
career-changing moment." ...the vegetation index would be able to
answer even larger questions about Africa's vegetation. ...Prince had
seen the effect of devastating drought in Africa's Sahel,
a...semi-arid, sparse savanna immediately south of the Sahara Desert. A
list of Sahelian countries is a yearbook of famine: Sudan, Chad, Niger,
Mali, Mauritania, Ethiopia, Burkina Fasso, and Senegal. A string of dry
years leading up to the early 1980s shriveled vegetation throughout the
Sahel, causing some people to fear that the Sahara Desert was steadily
marching southward, .... Ground studies had produced dramatic pictures
of formerly productive lands reduced to apparent desert. Many people
extrapolated from these local examples of desertification to propose
that the whole Sahel was becoming a desert, but no one had surveyed the
entire Sahel. It was far too large a task. ..."When I saw the
vegetation index data, I realized that it was exactly the scale we
wanted for studying desertification," says Prince. "There is no other
way of seeing big enough areas at high enough frequency." ....
Archive of Past Articles for Chapter 3