07 Nov 2013:
Grand Canyon 'Zombie'
Uranium Mine on Hold for Financial Reasons
The reopening of a major uranium mine near the Grand Canyon has been put on hold until December 2014 or whenever a federal court rules on the proposed revival of the mine, the Guardian reports
. The owner of Canyon
Grand Canyon's South Rim
Mine, Energy Fuels Resources, cited falling uranium prices, which have reached a near five-year low, and litigation costs as reasons for the decision. In April the Canyon Mine and other so-called "zombie mines"
were given federal approval to reopen based on their rights at the time they closed, despite an Obama administration ban on new hard-rock mines in areas larger than 1 million acres. Grand Canyon National Park officials say reopening the Canyon Mine, located six miles from the popular South Rim entrance, and other uranium mines could affect scarce water sources in the area. Environmental groups and the Havasupai Indian tribe sued the U.S. government in 2012, contending the environmental review of the mine's impacts was outdated.
Photo Essay: Focusing a Lens on
China's Environmental Challenges
Photographer Sean Gallagher has lived and worked in China for seven years, visiting nearly all of its provinces as he documents the country’s daunting ecological problems and its widely varied landscapes. In a Yale Environment 360 photo essay
, the Beijing-based photojournalist chronicles China’s widespread water and air pollution, the battle against the desertification that has spread across the country's northern regions, and the threats to the nation's biodiversity.
View the photo gallery.
08 Oct 2013:
Eighty Percent of Ecosystems
Vulnerable to Climate Change, Study Finds
Climate change could significantly transform up to 86 percent of the planet's land ecosystems under worst-case global warming scenarios, according to researchers at Germany's Potsdam Institute for Climate Impact Research
. That estimate is based on a 4 to 5 degree C temperature increase by the year 2100 — a scenario that is plausible given many nations' reluctance to enact greenhouse gas emissions limits, the researchers say. Even if global temperatures are kept to 2 degrees C above preindustrial levels, 20 percent of natural land ecosystems are at risk of moderate or major changes, especially high-altitude and high-latitude regions. Such changes could include boreal forests being transformed into temperate savannas, trees growing in thawed Arctic tundra, or even a dieback of some of the world's tropical forests. "Essentially, we would be leaving the world as we know it," says Sebastian Ostberg, who led the research. "The findings clearly demonstrate that there is a large difference in the risk of global ecosystem change under a scenario of no climate change mitigation compared to one of ambitious mitigation," he added.
02 Oct 2013:
Excess Radioactivity and Metals
Found in Pennsylvania Fracking Wastewater
Researchers found high levels of radioactivity, metals, and salts in sediments and water downstream from a Pennsylvania facility that treats fracking wastewater. Radioactivity levels downstream of the treatment plant were about 200 times higher than in surrounding areas, and concentrations of some salts and metals were also higher than background levels, the scientists reported in Environmental Science and Technology
. The Duke University team traced the radioactivity's source to the Marcellus Shale formation, which is naturally high in salts and radioactivity. Although the treatment plant removes more than 90 percent of the radioactive metals radium and barium, the effluent still exceeds federal limits for radioactive waste disposal, the researchers said. Plants, fish, and other organisms near the facility are potentially at risk for radium bioaccumulation. Downstream, carcinogenic byproducts can form when water with excess levels of the salt bromide mixes with disinfection chemicals at municipal drinking water plants, the study said. A mile downstream from the treatment facility, bromide levels were 40 times higher than background levels, the researchers reported.
24 Sep 2013:
Major Wind and Rain Belts
Could Shift North as Earth Warms
A study of warming at the end of the last Ice Age indicates that future warming caused by the burning of fossil fuels will likely shift the planet's rain and wind belts northward, say researchers
at Columbia University's Lamont-Doherty Earth Observatory. Regions that are already dry — including the western U.S., western China, and the Middle East — could grow drier, while equatorial Africa and monsoonal Asia may become wetter. An examination of data such as polar ice cores and ocean sediments shows that as the last Ice Age ended 15,000 years ago, northward shifts in the tropical rain belt and mid-latitude jet stream occurred as the temperature gradient between the northern and southern hemispheres increased. That sharper gradient came about because the land mass-dominated northern hemisphere warmed faster than the ocean-dominated southern hemisphere, according to the study, published in the Proceedings of the National Academy of Sciences
. Researchers say a similar pattern could develop in years to come as the northern hemisphere continues to warm faster than the southern hemisphere.
17 Sep 2013:
Major Company Backs Out
Of Pebble Mine Project in Alaska
A major mining company has withdrawn its participation in Alaska's Pebble Mine project, dimming the controversial project's prospects of moving forward, the Anchorage Daily News reports
. The British Mining giant, Anglo American, said it was pulling out of the project to focus on lower-risk mining ventures — a tacit acknowledgment that opposition among fishermen,
Bristol Bay watershed
indigenous groups, and environmentalists was making it increasingly unlikely that the Pebble Mine would receive the necessary state and federal approvals. The opposition is focused on concerns that the massive gold and copper mine would threaten Bristol Bay and endanger the world's richest wild salmon fishery
. Northern Dynasty Minerals, a Canadian company, continues to back the project, but a company official said the firm would have trouble moving forward without a partner.
11 Sep 2013:
Arsenic in Vietnam Groundwater
Slowly Moving Toward Hanoi, Study Says
As the population and water needs of Hanoi mushroom, the capital city of Vietnam is slowly drawing poisonous arsenic into the aquifer that supplies its drinking water, say researchers from the U.S. and Vietnam
. Water contaminated with arsenic has moved more than a mile
The Red River
closer to the aquifer over the last 40 to 60 years, the researchers report in Nature
, due to the city's increasing water demand; municipal pumping in Hanoi doubled between 2000 and 2010. The good news, says lead researcher Alexander van Geen of Columbia University's Lamont-Doherty Earth Observatory, is the contaminated groundwater "is not moving as fast as we had feared it might.” This will give Hanoi officials time, perhaps decades, to determine how to best deal with the problem. The study also determined why arsenic is leaching into the groundwater: As water containing arsenic mixes with high levels of organic carbon from the Red River and other surrounding aquifers, the chemistry changes and arsenic dissolves in the water.
05 Sep 2013:
Swapping Corn for Rice Benefits
China's Miyun Reservoir, Study Shows
After years of contamination and decreasing output, China's Miyun Reservoir is rebounding
, say researchers from China and the U.S. Rice farming had contaminated and tapped the reservoir, which lies 100 miles north of Beijing and is the main water source for the city's 20 million inhabitants. But four years ago, the Chinese government began paying farmers to grow corn instead, which requires less water and leads to less fertilizer and sediment runoff than rice farming
. Now, water quality tests show that fertilizer runoff declined sharply, the researchers found, and the amount of reservoir water available to Beijing and surrounding areas has increased. Farmers also made more money growing corn instead of rice and were able to spend less time tending their crops, the study concluded
How High Tech Is Helping
Bring Clean Water to Rural India
Social entrepreneur Anand Shah runs Sarvajal, a company that seeks to bring clean water to remote villages in India by deploying solar-powered “water
ATMs,” which dispense water to residents with the swipe of a prepaid smart card. Sarvajal, launched in 2008, currently serves more than 110,000 rural customers and is now is moving into India’s urban slums, where people often spend hours a day waiting for trucks to deliver clean water. In an interview with Yale Environment 360
, Shah talks about the challenges of expanding access to clean water in India and the lessons his company has learned from its first five years of operation. “The solutions came from what we actually saw in the field, rather than being invented elsewhere,” he says, “and that’s what makes it work.”
Read the interview.
23 Aug 2013:
Arsenic in Groundwater
May Affect 20 Million People in China
Nearly 20 million people in China are exposed to high levels of arsenic in the water they use for drinking and cooking, a new model based on geological and
hydrological data and well samples shows. The model predicts high arsenic concentrations
(10 micrograms per liter or greater) across more than 580,000 square kilometers, according to Chinese and Swiss researchers, who published their findings in Science
. Researchers had long known that some regions had high arsenic concentrations, but it would have taken several decades to test the millions of wells in China. The new prediction combined the most recent tests with data about the underlying geology, soil characteristics, and topography.
26 Jul 2013:
Parched New Mexico Reservoir
Reveals Effects of Prolonged Drought
A pair of satellite images released by NASA this week
shows the effects of a severe drought on New Mexico’s largest reservoir, where water levels are at their lowest
levels in four decades. Earlier this week, the U.S. Army Corps of Engineers estimated that Elephant Butte reservoir in southern New Mexico was holding about 65,057 acre-feet of water, only 3 percent of its capacity of 2.2 million acre-feet, largely as a result of prolonged drought conditions and unusually low spring snowmelt from nearby mountains. That represents the lowest water levels in the reservoir since 1972. From the mid-1980s to 2000 the reservoir was nearly filled to capacity, as illustrated in a 1994 satellite image, top, released by NASA. The reservoir, fed by the Rio Grande, provides water for about 90,000 acres of agricultural land and about half the city of El Paso, Tex.
15 Jul 2013:
Map Shows Possible Link
Between Warmer Springs and Large Fires
An interactive tool produced by the group Climate Central illustrates how rising temperatures and reduced snowpack in the western U.S. have corresponded with an increase in wildfires
in recent decades. Based on
federal wildfire data from 1970 to 2012, the graphic shows how large fires in some western states — including Arizona, Colorado, and Idaho — have doubled or even tripled in four decades, a period when the average spring and summer temperatures in 11 states increased by more than 1.5 degrees F. According to the Climate Central analysis, Arizona has experienced the highest average increase in spring temperatures, about 1 degree F, which has likely been a key factor in the steep increase in fires covering more than 1,000 acres. Another key factor has been the decrease in mountain snowpack. During several seasons, unusually low amounts of spring snow caused extended droughts that helped drive more big fires.
02 Jul 2013:
Drought Tolerance in Plants
Boosted by New Synthetic Chemical
Scientists have identified a chemical that helps plants better tolerate drought conditions
, a discovery they say could help boost crop production as extreme weather
Click to enlarge
Cutler Lab/UC Riverside
Soybean plant, right, treated with quinabactin
conditions become more common. After testing thousands of different molecules, researchers at the University of California, Riverside found and named a chemical, quinabactin, that caused the pores, or stomata, in Arabidopsis plants to close firmly, thus preventing water loss. The action is similar to the way a naturally occurring stress hormone, known as abscisic acid (ABA), performs in drought-tolerant plant varieties. While it was previously known that ABA triggers the closing of stomata pores during dry periods, the hormone is far too expensive to apply in agricultural fields, scientists say. Writing in the Proceedings of the National Academy of Sciences
, the researchers report that the synthetic chemical mimics the effects of ABA but is much simpler chemically and cheaper to produce.
04 Jun 2013:
Nanofilter System Can Deliver
Clean Water to Rural Families for $2.50
Indian scientists have developed a filter system they say can provide clean water to rural families for less than $2.50 per year
and help reduce incidences of diarrhea that cause tens of thousands of deaths in the developing world annually. Writing in the Proceedings of the National Academy of Sciences
, researchers from the Indian Institute of Technology Madras (IITM) describe the filter, which contains a composite of nanoparticles, held within a sieve, that emit a stream of silver ions that eradicate water-based microbes. In producing the filter, the team used a material called aluminium oxyhydroxide-chitosan, which, because of its structure and the diameter of the silver nanoparticles, is optimal for releasing the silver ions at temperatures of between five to 35 degrees C. In addition, the material is widely available, and environmentally friendly, and it keeps concentrations of the silver ions below safe drinking water standards, lead author Thalappil Pradeep told ScieDev.Net
. So far, the scientists have installed the filters in water treatment plants in West Bengal, but are now seeking a company to produce the devices for widespread use.
31 May 2013:
Getting More ‘Crop-per-Drop’
In World’s Driest Agricultural Regions
Improvements in irrigation in the world’s driest regions could significantly boost food production and water sustainability, according to a new study
. In an analysis of how water is used for 16 staple food crops worldwide, including in regions with similar climates, a team of researchers identified specific areas where major efficiency improvements can be made in the so-called “crop per drop” — or the amount of food produced per liter of water. According to their findings, published in the journal Environmental Research Letters
, about 40 percent of the available water in some dry regions is used to produce about 20 percent of the food calories. But in other regions with similar climate conditions, the productivity is much greater, said Kate A. Brauman, a researcher at the University of Minnesota’s Institute on the Environment. If these less-productive regions could improve their crop-per-drop productivity by even a modest amount, she said, “this would increase annual production on rain-fed croplands by enough to provide food for about 110 million people.”
24 May 2013:
Majority of Earth’s Population
Faces Water Shortages by Mid-Century
A conference of 500 of the world’s leading water scientists issued a stark declaration
at the end of a four-day meeting in Germany, warning that within two generations a majority of the people on the planet will face problems obtaining ample supplies of clean water. At the meeting, “Water in the Anthropocene,” the scientists said that the of over-pumping of underground aquifers, soaring populations, pollution, the over-use of fertilizers, and climate change are seriously threatening supplies of freshwater
around much of the globe. Continuing on the current path will mean that most of Earth’s population “will be living under the handicap of severe water pressure,” the scientists said, adding, “This handicap will be self-inflicted and is, we believe, entirely avoidable.” The conference proposed a wide range of solutions, including better study and monitoring of water supplies, basic reform in irrigation and agriculture, and innovation in the institutions that set national and global water policy.
17 Apr 2013:
Outdated Management, Drought
Threaten Colorado River, Report Says
Drought, mismanagement, and over-exploitation of its waters have made the Colorado River — the lifeblood of the arid Southwest and drinking water source for 36 million people — among the most vulnerable rivers in
the U.S., according to the group American Rivers. In its annual report on “America’s Most Endangered Rivers
,” the organization placed the 1,400-mile Colorado at the top of the list of threatened rivers, saying the iconic river “is so dammed, diverted, and drained that it dries to a trickle before reaching the sea.” Proposals to remove more than 300,000 acre-feet of new water from the river and its tributaries, coupled with a projected reduction in its flow of 10 to 30 percent because of global warming, will add further stress to the Colorado system
. According to the report, outdated water management systems also threaten the Flint River in Georgia, the San Saba River in Texas, and the Little Plover River in Wisconsin. In the U.S. Southeast, storage ponds for coal ash pose a threat to the Catawba River, a major source of drinking water for parts of North Carolina and South Carolina.
26 Mar 2013:
China’s Utility Giants
Vulnerable to Water Scarcity, Report Says
China’s five largest power utilities, which depend on water-intensive, coal-fired stations to generate electricity, are vulnerable to water supply disruptions because they are centered in the country’s water-scarce northern regions, a new report says. According to Bloomberg New Energy Finance
, the five power generators — Huaneng, Datang, Huadian, Guodian, and China Power Investment — operate hundreds of gigawatts of thermal plants in the industrial northeast, where water resources are increasingly strained. Eighty-five percent of China’s power-generating capacity is in water scarce regions, said Maxime Serrano Bardisa, one of the report’s coauthors. The report said that major technical and policy shifts will be required to avert serious disruptions, including the addition of systems that use less water, such as closed-cycle or air-cooled systems. Such improvements could cost the utilities $20 billion in retrofit costs, the report said.
18 Mar 2013:
New Chinese Premier
Vows To Tackle Pollution With ‘Iron Fist’
China’s new premier, Li Keqiang, has vowed aggressive government action
to curb the rampant pollution that has provoked growing public outrage, saying the country would phase out “backward production
Smog covers Beijing in January
facilities” that have contributed to dangerous health conditions in numerous regions. Speaking at his first press conference, Li said the government would set deadlines to address the public health controversy, exemplified by choking air pollution over Beijing that has kept air quality at dangerous levels
since the beginning of the year. Chronic air pollution problems in major metropolitan areas, coupled with a recent episode in which more than 12,000 rotting pig carcasses
were discovered in a river that provides Shanghai’s drinking water, have triggered growing public protest. While Li offered few specific solutions, he promised “vigorous” efforts to tackle pollution. “We need to face the situation and punish offenders with no mercy and enforce the law with an iron fist,” he said. “We shouldn’t pursue economic growth at the expense of the environment.”
13 Mar 2013:
New Desalination Process
Slashes Costs of Producing Fresh Water
Lockheed Martin, one of the world’s largest military contractors, has developed a process that company officials say significantly reduces the amount of energy needed to desalinate water
, an innovation that could help communities worldwide tackle the growing threat of water scarcity. According to the company, the new process uses ultra-thin carbon membranes with holes large enough to allow water to pass through, but small enough to block the salt molecules in seawater, Reuters reports. Because the membranes have holes as thin as a single atom, the process would require far less energy than existing desalination technologies, which rely on reverse osmosis, the company says. “It’s 500 times thinner than the best filter on the market today and a thousand times stronger,” said John Stetson, a Lockheed Martin engineer. “The energy that’s required and the pressure that’s required to filter salt is approximately 100 times less.” A 2011 study
found that desalination technology could be the cheapest approach to meeting the planet’s growing water needs.
08 Mar 2013:
Largest U.S. Dam Removal
Releases Huge Amount of Sediment
Scientists tracking the aftermath of the largest dam removal in U.S. history say the dismantling of a dam in northwestern Washington state has unleashed about 34 million cubic yards of sediment and debris
that built up
A plume of sediment at the mouth of the Elwha River.
for more than a century. While about one-third of the 210-foot Glines Canyon Dam on the Elwha River still stands, vast amounts of sediment are already flowing downstream, allowing University of Washington (UW) scientists a rare opportunity to track the discharges and study their ecological impacts. Scientists say it is unclear where much of the sediment will end up — or what the environmental consequences will be. In an ongoing study, they will use sophisticated technology to track particles in the water and monitor their accumulation on the ocean floor. Scientists say the sediment — enough to fill 3 million truckloads — could create murkier water conditions, threatening the reproduction of salmon and blocking light for marine life.
27 Feb 2013:
Oxfam Ranks Food Giants on
Sourcing and Environmental Policies
The group Oxfam has published an online scorecard assessing the agricultural sourcing of the world’s biggest food and beverage companies, rating them on factors that include water resource management, climate
awareness, and transparency. Using publicly available information, the “Behind the Brands
” campaign rates the 10 companies with the largest overall revenues — including Nestlé, PepsiCo, Unilever, Mars, and General Mills — on their awareness and responsiveness to these issues and supply chain management. According to Oxfam's analysis, Europe-based companies Nestlé and Unilever earned the highest scores overall, receiving good marks for water management and workers’ rights. Seven of the 10 companies received the lowest possible score for land management
. Associated British Foods, Kellogg’s, and General Mills received the lowest overall scores. Oxfam says the scoreboard will be updated regularly.
19 Feb 2013:
New Global Standard Aims
To Reduce Water Waste by Businesses
The UK-based Carbon Trust has introduced what it calls the first global standard on water management and reduction
in hopes of encouraging more sustainable water use by businesses. The new standard, created by members of the group along with four early-adopting companies, including Coca-Cola Enterprises, will require businesses to show that they are measuring their water use and reducing consumption on a year-to-year basis, Carbon Trust executive Tom Delay told BBC News
. “We look at the various water supply methods: mains, surface water abstraction, groundwater, and rainwater collection,” he said. The Carbon Trust, which already helps business and governments reduce energy use and carbon emissions, decided to expand into water issues since freshwater scarcity is closely linked with climate change. According to a 2009 report
, global freshwater demand will outpace currently available supplies by 40 percent by 2030. In a survey of 475 companies in the U.S., UK, China, and Brazil, the Carbon Trust found that just one out of seven businesses have set targets for water reduction and report their performances publicly.
13 Feb 2013:
Middle East Water Loss
Is Starkly Documented by NASA Satellites
A pair of gravity-measuring NASA satellites has documented a precipitous drop in freshwater supplies in the arid Middle East
over the past decade. NASA said that since 2003 parts of Turkey, Syria, Iraq, and Iran had lost 144 cubic kilometers of total stored freshwater, an amount roughly equivalent to the water in the Dead Sea. NASA researchers attributed 60 percent of the loss to increased pumping of groundwater from underground reservoirs. An additional 20 percent of the loss came from soil drying up and snowpack shrinking, while the remaining 20 percent came from loss of surface water in lakes and reservoirs, according to the NASA study, to be published Friday in the journal Water Resources Research.
A drought in 2007 exacerbated all of these trends, but even without the drought scientists said that the rapidly growing population in the heart of the Middle East was using too much water at a time of increasing concern over intensifying droughts caused by climate change. The GRACE satellites — short for Gravity Recovery and Climate Experiment — measure changes in gravity
, in this case caused by the falling of water reserves, which alters the earth’s mass.
Interview: What’s Damaging U.S.
Salt Marshes and Why It Matters
For centuries, salt marshes along the U.S. coast have been disappearing, with some experts estimating that 70 percent have been lost to development, rising seas,
and other threats. One factor scientists always thought marshes could withstand was nutrient enrichment, such as the flow of nitrogen and phosphorus from fertilizers and septic systems. But a nine-year study led by Marine Biological Laboratory scientist Linda Deegan shows that an over abundance of nutrients may be contributing to the demise of these salt marshes. In a Yale Environment 360
interview, Deegan describes the study's implications and the vital services that would be lost if marshes disappear, from nourishing marine species to providing a barrier for coastal communities during storms such as Hurricane Sandy. Read the interview
11 Dec 2012:
NASA Visualization Captures
Record Year for Wildfires in the U.S.
This year has been an unusually severe one for wildfires in the U.S., with more than 9.1 million acres of land burned through the end of November, federal officials say. The total affected area, which is depicted in a new NASA map, is already the third-largest since records were first kept
in 1960, and will likely break previous
records by year’s end. The most intense fires occurred in the western U.S., where several major fires during the early summer — sparked by a combination of drought, light winter snow pack, and the long-term effects of climate change — forced evacuations in some areas. In the visualization, which shows all fires that occurred between Jan. 1 and Oct. 31, areas of yellow and orange indicate larger and more intense fires, while many of the less intense fires, shown in red, represent prescribed burns started for brush clearing or agriculture and ecosystem management. The visualization was based on data collected by NASA satellites.
Interview: Designing Green Cities
To Meet 21st Century Challenges
Landscape architect Martha Schwartz is a passionate believer in the role that landscape can play in urban sustainability. Great landscape design, she says, can
Martha Schwartz Partners
moderate extreme heat, recycle water, reduce energy use, lower carbon emissions, and attract people to urban areas. Following these principles, her London-based firm, Martha Schwartz Partners
, has designed such projects as Dublin’s Grand Canal Square; Exchange Square, in Manchester, England; and Abu Dhabi’s Corniche beachfront area. In an interview with Yale Environment 360
, Schwartz, a professor at Harvard University’s Graduate School of Design, talks about the importance of incorporating cultural values in urban design, explains why the design of streets and parking lots is as important as the design of parks, and discusses why the U.S. lags behind many other nations in the greening of its cities. Read the interview
20 Nov 2012:
U.S.-Mexico Reach Accord
On Sharing Colorado River Water
The U.S. and Mexico have reached an agreement on how to share water from the Colorado River
, a five-year deal crafted to help both nations prepare for future droughts. Under the agreement, regional water agencies in California, Arizona, and Nevada will purchase nearly 100,000 acre-feet of water from Mexico’s share of the river, enough to cover 200,000 households for a year. In return, Mexico will receive $10 million to repair damage along hundreds of miles of irrigation canals caused by a 2010 earthquake — repairs that will bring thousands of acres of farmland back into production, according to the Los Angeles Times
. The U.S. will also promise to buy additional water and allow it to flow to the delta south of the border, a region that has seen reduced water flow in recent years
as U.S. water demands upstream have increased. In addition, Mexico will agree to take lesser water during periods of drought, but will be allowed to keep some of its water in Lake Mead
, the vast reservoir that straddles Nevada and Arizona, providing badly needed storage capacity.
02 Nov 2012:
Sea-Level Rise Projections
Ignored Critical Feedbacks, Researcher Says
A U.S. researcher says projected sea-level rise over the next century has been underestimated because current models fail to consider several critical feedbacks
that might accelerate rising seas in the coming decades. While the 2007 report of the Intergovernmental Panel on Climate Change predicted that global sea levels could rise 0.2 to 0.5 meters by 2100, current projections suggest that seas could rise a meter or more. One of the factors ignored by earlier models, says University of Colorado geologist Bill Hay, is the influx of warm, briny ocean water into the Arctic that occurs when melting fresh water is released, a phenomenon he says acts as a sort of “heat pump” in the Arctic, adding more ice-free waters, which then absorb more solar energy. According to Hay, who will present his findings at the annual meeting of The Geological Society of America, another factor that was ignored is the potential melting of large ice sheets in Greenland and western Antarctica. A third feedback, he said, is the vast amounts of groundwater being removed to address humankind’s surging water needs, much of which ultimately ends up in the oceans.
13 Sep 2012:
In Himalaya Mountains,
A Mixed Picture of Glacial Melting
A new study says that glaciers in the Himalayas are reacting to climate change in different ways
, with glaciers in the eastern and central Himalayas retreating at accelerating rates, while glaciers in the western Himalaya and Hindu Kush region are more stable and possibly even growing in places. According to a report by the National Research Council
, many of the glaciers of the Himalayan region are retreating at rates comparable to other parts of the world, but changes to glacial meltwater are not likely to make a significant difference in water availability at lower elevations, which rely more on monsoon rains and snowmelt. If the the current rate of glacial retreat continues, however, the report said that high-elevation areas of some river basins could see altered seasonal water flow. In addition, researchers say the melting of glaciers could affect regional water security during periods of drought or “similar climate extremes.” The Himalaya/Hindu Kush region is the source of several river systems — including the Indus, Ganges, and Brahmaputra — that supply drinking water and irrigation to 1.5 billion people.