 | Nuclear Winter: Nuclear War would be an Unprecedented Human Catastrophe - by Carl Sagan - 2010-11-09 |
| Even small nuclear wars can have devastating climatic effects... |
Michele Kearney's Environmental Blog - Environmental degradation and waning natural resources including energy resources threaten U.S. security. And the loss of renewable natural resources, including forests, fresh water, fish and fertile soils, can drive political instability and conflict in the developing world, and around the globe. In short, natural resoures, energy and the environment are national security issues.
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Friday, November 12, 2010
Nuclear Winter: Nuclear War would be an Unprecedented Human Catastrophe - by Carl Sagan - 2010-11-09
Arabs face severe water crisis by 2015
Lebanon, once considered to have an abundance of water, is threatened with acute shortages as the Arab world lurches toward severe water scarcity as early as 2015. For Lebanon, which has long neglected to take measures to conserve and manage its water resources, the crisis couldn't come at a worse time: The government is gripped by political crisis that many fear could lead to renewed civil war; the decision-making process has been paralyzed; and a 10-year water plan adopted in 2002 has ground to a halt.
The Cabinet, burdened with a $54 billion public debt, decided recently to delay all discussion on a proposal by Water and Energy Minister Jibran Bassil to build 11 dams on Lebanon's several rivers.
Fadi Comair, general director of hydraulic and electrical resources, says that enlisting the private sector is the only way to solve the worsening water problem.
"We cannot implement infrastructure projects if the private sector does not intervene," he told The Daily Star, Lebanon's English language newspaper. "Without the private sector we can do nothing."
Comair, lashing out at the sectarian divisions that plague Lebanon, declared: "If politicians in our country had any ethics they would have taken care of such projects instead of attacking each other on TV every day."
The World Bank recently urged major investment in Lebanon's ramshackle water infrastructure while noting that the tiny country's water resources are equivalent to 49,830 cubic feet per capita, one of the highest in the Middle East and North Africa.
Other states in the arid region can only watch in wonder as Lebanon's government ignores a problem most would gladly take on if they had the same water resources.
The Arab world has 5 percent of the world's population -- an estimated 360 million people -- but only 1.4 percent of the planet's renewable fresh water supply.
By 2025, the Arab population will likely total around 568 million, gravely stretching shrinking natural water resources.
By the end of the century, the report noted, climate change will mean a 25 percent decrease in precipitation and a matching increase in evaporation rates.
The wealthier Arab states, primarily the oil producers of the Persian Gulf that have no rivers and little rainfall, rely heavily on desalination plants. They account for half the world's desalination capacity, a costly undertaking. Other states, including Egypt and Jordan, plan to develop nuclear power to drive such plants.
But that will take years to achieve. And even in the Arabian Peninsula, water consumption is rising as the population swells.
Water use there now exceeds renewable sources, Sweden's Stockholm International Water Institute says, and that situation is unlikely to change anytime soon.
In the meantime, a November report by the Arab Forum for Environment and Development said that in less than five years from now Arabs will have to get by on around 7,650 cubic feet of water a year each. That's less than 1-10th of the world average of 196,800 cubic feet of water per capita.
"The Arab world is already living a water crisis that will only get worse with inaction," the report said.
Thirteen Arab states are among the 19 in the world most affected by water scarcity and citizens of eight of those Arab countries have to survive on less than 7,060 cubic feet of water per year.
"Without fundamental changes in policies and practices, the situation will get worse, with drastic social, political and economic ramifications," the Arab Forum warned.
Limited resources mean water in the region plays a strategic role in national security, foreign policy and domestic stability.
Agriculture is a major drain on renewable water supplies because of irrigation and that could lead to states going to war over water resources in a region where sectarian and ethnic conflict as well as intrastate tensions are rife.
"Analysts, academics and diplomats remain divided over whether or not water will cause a war within the region, but they do agree on one thing: it will become an increasingly important and scarce resource in the coming decades," The Middle East Economic Digest observed recently.
Yemen, the Arab world's poorest state which is gripped by terrorism, civil strife and a collapsing economy, could be a case in point. It's expected to run out of water in the next few years.http://www.terradaily.com/reports/Arabs_face_severe_water_crisis_by_2015_999.html
The Cabinet, burdened with a $54 billion public debt, decided recently to delay all discussion on a proposal by Water and Energy Minister Jibran Bassil to build 11 dams on Lebanon's several rivers.
Fadi Comair, general director of hydraulic and electrical resources, says that enlisting the private sector is the only way to solve the worsening water problem.
"We cannot implement infrastructure projects if the private sector does not intervene," he told The Daily Star, Lebanon's English language newspaper. "Without the private sector we can do nothing."
Comair, lashing out at the sectarian divisions that plague Lebanon, declared: "If politicians in our country had any ethics they would have taken care of such projects instead of attacking each other on TV every day."
The World Bank recently urged major investment in Lebanon's ramshackle water infrastructure while noting that the tiny country's water resources are equivalent to 49,830 cubic feet per capita, one of the highest in the Middle East and North Africa.
Other states in the arid region can only watch in wonder as Lebanon's government ignores a problem most would gladly take on if they had the same water resources.
The Arab world has 5 percent of the world's population -- an estimated 360 million people -- but only 1.4 percent of the planet's renewable fresh water supply.
By 2025, the Arab population will likely total around 568 million, gravely stretching shrinking natural water resources.
By the end of the century, the report noted, climate change will mean a 25 percent decrease in precipitation and a matching increase in evaporation rates.
The wealthier Arab states, primarily the oil producers of the Persian Gulf that have no rivers and little rainfall, rely heavily on desalination plants. They account for half the world's desalination capacity, a costly undertaking. Other states, including Egypt and Jordan, plan to develop nuclear power to drive such plants.
But that will take years to achieve. And even in the Arabian Peninsula, water consumption is rising as the population swells.
Water use there now exceeds renewable sources, Sweden's Stockholm International Water Institute says, and that situation is unlikely to change anytime soon.
In the meantime, a November report by the Arab Forum for Environment and Development said that in less than five years from now Arabs will have to get by on around 7,650 cubic feet of water a year each. That's less than 1-10th of the world average of 196,800 cubic feet of water per capita.
"The Arab world is already living a water crisis that will only get worse with inaction," the report said.
Thirteen Arab states are among the 19 in the world most affected by water scarcity and citizens of eight of those Arab countries have to survive on less than 7,060 cubic feet of water per year.
"Without fundamental changes in policies and practices, the situation will get worse, with drastic social, political and economic ramifications," the Arab Forum warned.
Limited resources mean water in the region plays a strategic role in national security, foreign policy and domestic stability.
Agriculture is a major drain on renewable water supplies because of irrigation and that could lead to states going to war over water resources in a region where sectarian and ethnic conflict as well as intrastate tensions are rife.
"Analysts, academics and diplomats remain divided over whether or not water will cause a war within the region, but they do agree on one thing: it will become an increasingly important and scarce resource in the coming decades," The Middle East Economic Digest observed recently.
Yemen, the Arab world's poorest state which is gripped by terrorism, civil strife and a collapsing economy, could be a case in point. It's expected to run out of water in the next few years.http://www.terradaily.com/reports/Arabs_face_severe_water_crisis_by_2015_999.html
Invasive grass threatens U.S. grazing land
| An invasive species of "devil" weed in range lands in the western United States could make millions of acres of grazing land worthless, researchers say. Researchers at Oregon State University say the weed knows as medusahead has growth advantages over most other grass species that could allow it to continue to spread across much of the West and disrupt native ecosystems, a university release said Thursday. Their study comparing the "relative growth rate" of this invasive annual grass to that of other competing species in natural field conditions found that medusahead has a faster growth rate, a longer period of growth and produced more total biomass than any native grasses. "Medusahead is now spreading at about 12 percent a year over 17 western states," Seema Mangla, a researcher in the OSU College of Forestry, said. "Once established, it's very hard to get rid of. "It displaces native grasses and even other invasive species that animals can still eat," she said. "This is a devil species," she said. Native to the Mediterranean region, medusahead was imported to the United States in the late 1880s. The sharp and twisting points on the tips of medusahead can injure animals and give the plant its name, based on the female monster in Greek mythology who had hair composed of writhing snakes. The plant takes up other soil resources and its deep root system soaks up limited moisture. It creates fuel for wildfires, is virtually inedible and prevents many other plants from germinating, researchers say. Experts at the Oregon Department of Agriculture say once land is invaded by medusahead, it becomes largely worthless, incapable of supporting native animals, birds or livestock.http://www.seeddaily.com/reports/Invasive_grass_threatens_US_grazing_land_999.html |
Thursday, November 11, 2010
Leaking underground CO2 storage could contaminate drinking water
Leaking underground CO2 storage could contaminate drinking water
Leaks from carbon dioxide injected deep underground to help fight climate change could bubble up into drinking water aquifers near the surface, driving up levels of contaminants in the water tenfold or more in some places, according to a study by Duke University scientists. http://www.physorg.com/news/2010-11-leaking-underground-co2-storage-contaminate.html
Leaks from carbon dioxide injected deep underground to help fight climate change could bubble up into drinking water aquifers near the surface, driving up levels of contaminants in the water tenfold or more in some places, according to a study by Duke University scientists. http://www.physorg.com/news/2010-11-leaking-underground-co2-storage-contaminate.html
Wednesday, November 10, 2010
New Shipping Lanes in Melting Arctic Will Accelerate Global Warming
http://www.truth-out.org/new-shipping-lanes-melting-arctic-will-accelerate-global-warming65005
Lisa Song, Solve Climate: "In the next few decades, a warming Arctic will open up shorter shipping routes, potentially reducing the amount of fuel needed to travel between ports. But the increased amount of soot in the atmosphere could further accelerate the region's climate change, and the shorter distances won't generate enough fuel savings to offset the impact. Those are the key findings of a recent study published in the journal Atmospheric Chemistry and Physics. This new study is the first systematic analysis of how Arctic shipping could affect local climate."
Read the Article
Lisa Song, Solve Climate: "In the next few decades, a warming Arctic will open up shorter shipping routes, potentially reducing the amount of fuel needed to travel between ports. But the increased amount of soot in the atmosphere could further accelerate the region's climate change, and the shorter distances won't generate enough fuel savings to offset the impact. Those are the key findings of a recent study published in the journal Atmospheric Chemistry and Physics. This new study is the first systematic analysis of how Arctic shipping could affect local climate."
Read the Article
Modeling Glacier Fed Water Dependency
 The researchers investigated the whole river basin region of certain glaciers in the Himalayas, the Andes, the Caucasus Mountains, Siberia, North America and New Zealand. Credit: Uni Innsbruck |
The scientists gathered data on the amount of precipitation on certain glaciers and calculated when the water is discharged and available in populated areas.
"There is a big difference in whether the water is discharged in an arid period or in a period, when there usually is a lot of precipitation, e.g. in monsoon regions in Asia," explains Ben Marzeion.
"And there are regions, for instance around the Aral Sea, where precipitation happens in the mountain regions in winter. The glacier melt water runoff in summer is vital for the population living in this area."
The Innsbruck researchers modeled estimates that show human dependence on glacier melt in a certain region. They demonstrate that high-mountain communities are highly dependent on glacier melt water but the population density is usually relatively low in these regions.
"The impact is a lot more dramatic in mid latitude river basins, where the population density is a lot higher and glacier melt still contributes to the available water reservoir to a large extent," the climatologists explain.
Regional differences The incentive of the study was the widespread discussion about the impact of climate change on water availability in highly populated regions. "In the last few years numbers have been named that do not pass a closer examination," says glaciologist and climatologist Georg Kaser. "It is an exaggeration when it is claimed that the melting of glaciers endangers the water supply of 2 billion people."
With their study the Innsbruck scientists want to draw attention to the considerable regional differences regarding the problem of future water supply. "By all means, the expected climatic development may have detrimental effects for smaller high-mountain communities."
The data for the study was obtained from the World Glacier Inventory, global temperature and precipitation data and the Global Digital Elevation Model. The researchers investigated the whole river basin region of certain glaciers in the Himalayas, the Andes, the Caucasus Mountains, Siberia, North America and New Zealand.
"In principle, this is a simple research approach, which, nevertheless, provides us with important arguments for a more differentiated discussion in climate research," says Georg Kaser, who is pleased about the results of the study, which has been published in the renowned scientific journal Proceedings of the National Academy of Sciences (PNAS).
"With regard to the next report issued by the Intergovernmental Panel on Climate Change (IPCC), our data can be seen as the basis for regionally more precise estimations and they show that the impact of the expected climate change may be higher in some regions than in others," says Kaiser
Fish stocks dwindle as trawlers empty Asia's seas
 |
For big fish "finding a mate is a difficult task. They have to swim a long distance to find one," said Edward Allison from the World Fish Center in Malaysia's northern resort island of Penang.
One of the culprits is bottom trawling, which involves dragging huge, heavy nets along the sea floor. Large metal plates and rubber wheels attached to the nets move along the bottom and crush nearly everything in their path.
Allison said the habitat for young fish, or fry, is also shrinking because the mangrove swamps which provide food and protection are being obliterated by coastal development including tourist resorts.
Demand for top-quality seafood, from Southeast Asian nations themselves and from Hong Kong and China, is another major factor behind the emptying of the seas.
According to World Fish data, there were 10 times more fish in the Gulf of Thailand in 1965 than 30 years later.
In Malaysia the decline was between 80 and 90 percent while in the Philippines it is estimated that there was a 46-78 percent dropoff in fish stocks.
There is little data from other countries without the resources to carry out the studies, but World Fish believes the rate of decline in those three countries is reflected across Southeast Asia.
In Tanjung Karang, a fishing village in central Malaysia on the banks of the murky Tengi river which flows into the Malacca Strait, coastal fishermen are gloomy as they come ashore to sell their daily catch.
After spending four hours at sea Kamarul Nizam, 35, managed to net only a few kilos of small prawns and cheap catfish. He sells them to Gan Soon Heng, a wholesaler who has been in the business for more than two decades.
Sitting in his wooden shop on the banks of the Tengi, Gan gives Kamarul about 30 dollars -- meagre pay for a hard day's work, as half is eaten up in costs.
Gan shows off a 37 kilo (81 pound) stingray, a 12 kilo garoupa and a long Spanish mackerel.
"Such a big stingray is rare. Even the 12 kilo garoupa is considered small. Twenty years ago you could catch much bigger fishes. Now you only get small ones," he said as he pointed to a few palm-sized stingrays lying in an icebox.
Tiew Kian Hap, 44, has fished the Malacca Strait for three decades, trawling for giant stingray, redfish and black pomfret.
"If we catch them we can make a profit. But their numbers now are much less. Also there are a lot of fishing boats out there hunting for them too," he said.
Instead, he mostly hauls in tiddlers that go to make belachan, a strong-smelling fish paste that is a vital ingredient in some popular Malaysian dishes.
Tiew lamented the lack of enforcement that sees big trawlers encroach close to the shore, wiping out the fry that, if left undisturbed, would grow into a valuable catch.
"Popular fishes like kambong or mackerel which we hope to catch get wiped out because even the small ones -- one to two inches -- are caught when their nets sweep the ocean floor," he said.
"There is no point reporting it because no action is taken."
Another fisherman, Ong Chee Hooi, 33, said the decline had been sharp in the past five years, and that even the mud crabs that used to be plentiful in the mangroves were disappearing.
"Their numbers have fallen. Factories and houses put up by the coast are polluting the water and this is killing the mangrove swamps," he said.
Allison said the use of dynamite and cyanide to fish in coral reefs, common in Indonesia and the Philippines, also poses a serious threat.
He urged enforcement authorities to adopt conservation measures such as encouraging the use of hook and line traps that net only targeted fish, and aquaculture to produce popular species.
"The aquatic system is quite resilient and they can recover if we can remove some of the pressures. What is needed is the political will and motivation to do so," he said.
Climate Change Assessments
- The Rise of the Arctic - Laurence Smith, Wall Street Journal
- China Is Winning the Green Energy Race - Thomas Friedman, NY Times
- Does Climate Change Cause Civil War? - Michael Levi, CFR
- Gillard Faces Rudd-made Climate Trap - Dennis Shanahan
- Russia Can't Afford Climate Inaction - Anthony Giddens, Financial Times
- The Global Warming Deniers Are Wrong - Johann Hari, The Independent
- Looming Disaster at the Top of the World - Thomas Homer-Dixon, NY Times
- Russia & Pakistan: Is Climate Change to Blame? - Washington Post
- Time for a Joint U.S.-Canada Carbon Tax - David Frum, National Post
- Australia's Foreign Policy Challenges - Fergus Hanson, The Australian
- Europe's Greens Embrace Decline - Bjorn Lomborg, Korea Times
- How Kevin Rudd Lost His Nerve - Peter Hartcher, Sydney Morning Herald
- A U.S.-China Climate Surge? - S. Julio Friedmann, Jordan Times
- The Root of Climate Email Fiasco - George Monbiot, The Guardian
- Women at the Heart of U.S. Foreign Policy - Hillary Clinton, The Times
- Global Warming Skeptics Ignore Arctic War - Walter Rodgers, CS Monitor
- Three Lessons from Copenhagen - Brahma Chellaney, Japan Times
- World Cools Toward Warmists - Paul Chesser, Washington Times
- Will Warming Force Refugees North? - Council on Hemispheric Affairs
- Don't Give Up on Climate Change - New York Times
- Climate Change and Open Science - L. Gordon Crovitz, Wall St. Journal
- A Contrived Attack on Climate Science - Jeffrey Sachs, The National
- How Rich-Poor Gap Sank Copenhagen - Lenore Taylor, The Australian
- Climate Change Is Costing India Millions - Supriya Sule, The Hindu
- Let the Markets Fight Global Warming - Malcolm Turnbull, The Australian
- India Now Supports Discredited IPCC - Barun Mitra, Wall Street Journal
- Climate Strategy on Road to Nowhere - Bjorn Lomborg, Globe and Mail
- Climate Science: Truth and Tribalism - The Guardian
- The Bright Side of Global Warming - Anne Jolis, Wall Street Journal
- Climate Change: What Next? - R.K. Pachauri, The Hindu
- Believe It: The Planet Will Survive - Steve Janke, National Post
- Can We Still Trust Climate Forecast? - Gerald Traufetter, Der Spiegel
- Climate Change's Latest Storm - Wall Street Journal
- Europe's Post-Copenhagen View of Obama - Steven Hill, IHT
- Developed Nations Obstruct Climate Progress - Lu Xuedu, China Daily
- China Is Leading the Green Leap - Thomas Friedman, New York Times
- How To Bridge the Climate Change Debate - Andrew Coyne, Maclean's
- Don't Make China a Climate Scapegoat - Dennis Pamlin, China Daily
- China Wants It Both Ways on Climate - Brahma Chellaney, Japan Times
- Nation State Has Outlived its Usefulness - John Bruton, Irish Times
- George W. Bush Key to the Climate Change Movement - Greg Hunt
- World Needs Single Climate Authority - Euro. Council on Foreign Relations
- Stormy Times for Global Warmists - Michael Fumento, Forbes
- A Velvet Climate Revolution? - Laszlo Solyom, Jordan Times
- To Save the Planet, Save the Seas - Dan Laffoley, New York Times
- Don't Look to Beijing for Global Leadership - Greg Sheridan
- Copenhagen Talks Not Just About Energy - John Seager
- On Foreign-Policy Front, Consider Obama Lucky -- So Far - Ian Bremmer
- The Changing Climate in India - Andrew Light, Julian L. Wong, Sabina Dewan
- No More Hot Air in Copenhagen - Bjorn Lomborg
- Time for Climate Change Realism - Richard Haass
- Shining a Light on Climate Change - Ban Ki-moon
- Seven Ways to Build a Cleaner Planet - Tony Blair
- The Global Climate Imperative - R.K. Pachauri
Tuesday, November 9, 2010
$5 Trillion: The Cost Each Year of Rainforest Destruction
British researchers set out the economic impact of species destruction -- and their findings are changing world's approach to global warming. READ MORE
By Matt Chorley / Independent UK
Biofuel worse for climate than fossil fuel: study
Biofuels Fallacy: Why Burning Plants Instead of Fossil Fuels Won't Save the Climate The quest to replace black fuels with green fuels is just another resource and land grab by big corporations.
The quest to replace black fuels with green fuels is just another resource and land grab by big corporations. READ MORE
Jeff Conant: You and your colleagues at ETC Group are strong advocates of taking what I would call a reasoned approach to the deployment of new technologies; you're best known for having led the charge for a global ban on the infamous Terminator Seed, and you've just had a tremendous victory by winning a global moratorium on geoengineering experiments (see last week's piece on AlterNet). Now, you're releasing a report on another impending technological concern: synthetic biology.
Jim Thomas: The report is called "The New Biomassters: Synthetic Biology and the Next Assault on Biodiversity and Livelihoods." It's an exposé and argument against the new "bioeconomy" most OECD countries are now promoting as the next (supposedly "green") wave of industrial production -- switching from fossil fuels to biological material (biomass) as the key feedstock of the economy. As such, it encompasses biofuels, burning biomass for electricity, and using biomass for chemicals, plastics and other materials formerly sourced from petroleum. More at:
Monday, November 8, 2010
The International Space Weather Initiative by Dr. Tony Phillips for NASA Science News
 Although space weather is usually associated with Earth's polar regions--think, "Northern Lights"--the equator can be just as interesting. For example, there is a phenomenon in Earth's upper atmosphere called the "equatorial anomaly." It is, essentially, a fountain of ionization that circles the globe once a day, always keeping its spout toward the sun. During solar storms, the equatorial anomaly can intensify and shape-shift, bending GPS signals in unexpected ways and making normal radio communications impossible. |
"Strong solar storms can knock out power, disable satellites, and scramble GPS," says meeting organizer and ISWI executive director Joe Davila of NASA's Goddard Space Flight Center. "This meeting will help us prepare for the next big event."
A key problem organizers hope to solve is a gap - many gaps, actually - in storm coverage around our planet. When a big storm is underway, waves of ionization ripple through Earth's upper atmosphere, electric currents flow through the topsoil, and the whole planet's magnetic field begins to shake.
"These are global phenomena," says Davila, "so we need to be able to monitor them all around the world."
Climate scientists plan campaign against global warming skeptics
Report Reveals Forces Destroying Atlantic Bluefin Tuna By ANDREW C. REVKIN
A powerful and innovative international journalistic effort has revealed the web of interests — from boat captains to European government agencies to fish auctions — behind the devastation of Atlantic bluefin tuna.
I encourage you to explore the reporting by the International Consortium of Investigative Journalists and a companion documentary by Television for the Environment. (Also known by its lower-case acronym, tve, the nonprofit documentary unit was created in 1984 by WWF, known in the United States as the World Wildlife Fund, the United Nations Environment Program and the Britain’s Central TV). Here’s a video summary:
http://www.youtube.com/watch?v=jC2snB6db5Q&feature=player_embedded
Der Spiegel: Geologists Warning Of “Mega-Eruption”
Der Spiegel: Geologists Warning Of “Mega-Eruption”http://www.spiegel.de/wissenschaft/natur/0,1518,727092,00.html
Germany's Der Spiegel reports on the growling-ever-louder Indonesian Merapi volcano in an article titled: Geologists Warning of Mega-Eruption of Merapi.
The Merapi eruptions are becoming more violent – and the big bang could be just ahead. The Indonesian volcano has been spewing 800°C ash clouds for days.
Indonesia's volcanoes (Wikipedia)
According to Der Spiegel, 122 people have been killed, most on Friday. “Merapi is among the most dangerous volcanoes,” says geo-scientist Volker Steinbach of the German Federal Administration for Geoscience and Raw Materials (BGR). Der Spiegel adds:
Friday’s eruption is its worst this decade, says the chief geologist of the Energy Administration, Raden Sukhyiar, in the “Jakarta Post”. The biggest known eruptions occurred in 1006, 1369, 1786, 1822, 1872 – destroying a large number of villages – and 1930 when 1300 people perished.
Investigations of the volcano have revealed that an unprecedented Magma reservoir lurks underneath it, says Birger Lühr, a volcano researcher at the GFZ in Potsdam, Germany.
A rough estimate indicates that there is three times more magma than what was ejected by the Indonesian volcano Tambora in 1815 – the biggest eruption in the last 10,000 years, which led to a cooling of the climate globally.
Geoscientists aren’t sure what to make of this huge magma reservoir. As Der Spiegel reports, they are hesitant to make predictions of catastrophe (That’s only done in climate science, even though the odds are far less).
Word of a ‘mega-eruption’ is making the rounds among scientists. But apparently they are avoiding the use of the word to avoid being labelled preachers of disasters. ‘We can only speculate what the volcano will do,’ says Birger Lühr. Merapi is hardly predictable.
Merapi in 2005 (Wikipedia)
History shows, however, that volcanoes in Indonesia have a worrisome potential for catastrophic eruptions. Nature cannot be controlled. It can only be coped with.
Sunday, November 7, 2010
Volcanoes Have Shifted Asian Rainfall
 Large, explosive volcanoes such as Indonesia's Merapi (erupting here in 2006) have the potential to change weather patterns if their eruptions are big enough. |
Now, scientists have shown that eruptions also affect rainfall over the Asian monsoon region, where seasonal storms water crops for nearly half of earth's population.
Tree-ring researchers at Columbia University's Lamont-Doherty Earth Observatory showed that big eruptions tend to dry up much of central Asia, but bring more rain to southeast Asian countries including Vietnam, Laos, Cambodia, Thailand and Myanmar-the opposite of what many climate models predict. Their paper appears in an advance online version of the journal Geophysical Research Letters.
The growth rings of some tree species can be correlated with rainfall, and the observatory's Tree Ring Lab used rings from some 300 sites across Asia to measure the effects of 54 eruptions going back about 800 years.
The data came from Lamont's new 1,000-year tree-ring atlas of Asian weather, which has already produced evidence of long, devastating droughts; the researchers also have done a prior study of volcanic cooling in the tropics.
"We might think of the study of the solid earth and the atmosphere as two different things, but really everything in the system is interconnected," said Kevin Anchukaitis, the study's lead author. "Volcanoes can be important players in climate over time."
River Flows Across US Altered By Land And Water Management
 Flows are altered by a variety of land- and water-management activities, including reservoirs, diversions, subsurface tile drains, groundwater withdrawals, wastewater inputs, and impervious surfaces, such as parking lots, sidewalks and roads. |
"Findings show the pervasiveness of stream flow alteration resulting from land and water management, the significant impact of altered stream flow on aquatic organisms, and the importance of considering this factor for sustaining and restoring the health of the Nation's streams and ecosystems."
Flows are altered by a variety of land- and water-management activities, including reservoirs, diversions, subsurface tile drains, groundwater withdrawals, wastewater inputs, and impervious surfaces, such as parking lots, sidewalks and roads.
"Altered river flows lead to the loss of native fish and invertebrate species whose survival and reproduction are tightly linked to specific flow conditions," said Daren Carlisle, USGS ecologist and lead scientist on this study.
"These consequences can also affect water quality, recreational opportunities and the maintenance of sport fish populations."
For example, in streams with severely diminished flow, native trout, a popular sport fish that requires fast-flowing streams with gravel bottoms, are replaced by less desirable non-native species, such as carp. Overall, the USGS study indicated that streams with diminished flow contained aquatic communities that prefer slow moving currents more characteristic of lake or pond habitats.
"Management practices related to water demand continue to alter stream flows in many places," said Jeff Ostermiller, Water Quality Manager with the Utah Division of Water Quality.
"Understanding the ecological effects of these flow alterations helps water managers develop effective strategies to ensure that water remains sufficiently clean and abundant to support fisheries and recreation opportunities, while simultaneously supporting economic development."
Annual and seasonal cycles of water flows - particularly the low and high flows - shape ecological processes in rivers and streams. An adequate minimum flow is important to maintain suitable water conditions and habitat for fish and other aquatic life. High flows are important because they replenish floodplains and flush out accumulated sediment that can degrade habitat.
"While this study provided the first, national assessment of flow alteration, focused studies within specific geographic regions will provide a better understanding of the ecological effects of altered stream flows, which can be more effectively applied to local water management challenges," said Carlisle.
Time For A Rain Dance
 File image. |
In the most comprehensive reassessment of the effects of cloud seeding over the past fifty years, new findings from Prof. Pinhas Alpert, Prof. Zev Levin and Dr. Noam Halfon of Tel Aviv University's Department of Geophysics and Planetary Sciences have dispelled the myth that seeding is an effective mechanism for precipitation enhancement.
The findings were recently reported in Atmospheric Research.
Throwing seeds into the wind During the course of his study, Prof. Alpert and his colleagues looked over fifty years' worth of data on cloud seeding, with an emphasis on the effects of seeding on rainfall amounts in a target area over the Sea of Galilee in the north of Israel.
The research team used a comprehensive rainfall database and compared statistics from periods of seeding and non-seeding, as well as the amounts of precipitation in adjacent non-seeded areas.
"By comparing rainfall statistics with periods of seeding, we were able to show that increments of rainfall happened by chance," says Prof. Alpert. "For the first time, we were able to explain the increases in rainfall through changing weather patterns" instead of the use of cloud seeding.
Most notable was a six year period of increased rainfall, originally thought to be a product of successful cloud seeding. Prof. Alpert and his fellow researchers showed that this increase corresponded with a specific type of cyclones which are consistent with increased rainfall over the mountainous regions.
They observed that a similarly significant rain enhancement over the Judean Mountains, an area which was not the subject of seeding.
The researchers concluded that changing weather patterns were responsible for the higher amount of precipitation during these years. Their research method may be useful in the investigation of cloud seeding in the U.S. and other regions.
Considering the alternatives Despite being relatively expensive, there are more than 80 cloud seeding projects around the world, according to a recent World Meteorological Organization report. In Beijing, China, for example, Prof. Alpert notes, a large amount of chemical particles were introduced to the clouds to inhibit precipitation - a process called "overseeding" - to limit rainfall during the 2008 Olympics.
Seeding is also used in the Sierra Mountains of California and in Wyoming to try to increase precipitation in the mountains, thus increasing water levels in reservoirs. However, he says, there is no proof that this method is successful.
The only probable place where cloud seeding could be successful, Alpert says, is when seeding is performed on orographic clouds, which develop over mountains and have a short lifespan. In this type of cloud, seeding could serve to accelerate the formation of precipitation.
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