Hikers ascend through the smog of  Los Angeles, one of six cities where researchers studied the effects of air pollution on the heart. By Flickr User Jason Morrison

One morning a couple of years ago, I decided to take a jog around the perimeter of my hotel in Delhi, India. A little bit of exercise might mitigate the crushing jetlag after my 24-hour flight from California, I thought. Within a minute or two of sucking in the city’s soot-filled air, my lungs and eyes were scorched. While I knew that Delhi’s air quality was bad, I had no idea it’s the 12th worst in the world—nor was I aware of precisely how damaging air pollution can be to the body.

As we’ve written about recently, researchers have discovered that smog can cause lung cancer and that nano-particles in the air burrow through cell membranes, possibly damaging the lungs and the circulatory system. But a new study published today in the journal PLOS Medicine shows that exposure to fine particulate matter in the air may be linked to a faster hardening of the arteries in otherwise healthy people, which can lead to increases in stroke and heart attack.

The study, conducted by researchers from University of Michigan and University of Washington, followed nearly 5,500 people—all heart-disease-free—from six American metro areas (Baltimore; Chicago; Los Angeles; New York City; Winston Salem, North Carolina and St. Paul, Minnesota). Scientists began the study by conducting ultrasound tests to measure the thickness of each participant’s right common carotid artery, which supplies blood to the head, neck, and brain.

Residents of New York City participated in a study that linked air pollution to increased risk of heart attack and stroke. By Flickr user JRGCastro

The participants’ home addresses were then recorded, and the researchers tapped the Environmental Protection Agency’s Air Quality System, a database of air quality levels gathered by monitors throughout the country, to gauge the amount of fine particulate matter in their neighborhoods. The scientists were able to factor in variables including proximity to major streets and highways, which allowed for a great deal of precision–air pollution concentrations varied, as it turned out, even within specific neighborhoods. Within the next five years, the thickness of each participant’s artery was tested once more. The scientists estimated their exposure to fine particulate matter during the period between the exams.

What they found was that exposure to higher concentrations of fine particulate air pollution correlated with an accelerated thickening of the arteries. Conversely, reductions in air pollution were linked with a slower progression of arterial thickening. Such a thickening or hardening of the arteries can eventually block the flow of blood to the head, resulting in stroke, or to the heart, causing heart attack.

“Linking these findings with other results from the same population suggests that persons living in a more polluted part of town may have a 2 percent higher risk of stroke as compared to people in a less polluted part of the same metropolitan area,” study author Sara Adar said in a statement.

The findings may also help shed light on previous studies that have linked chronic air pollution exposure and death, and may encourage lawmakers to support clean air standards. “Our findings furthermore bolster recent reports that falling pollution levels in the United States after the adoption of the Clean Air Act are associated with reduced mortality and increased life expectancy,” the study authors wrote.

Air quality in the United States is far superior to that in many parts of the world. But where is air quality the worst? The World Health Organization’s database of global air pollution statistics reveals that low- and middle-income regions of the Eastern Mediterranean have the worst air quality overall. Among cities, Ahwaz in Iran is the world’s most polluted. Mongolia’s Ulan Bataar ranks second in air pollution and Delhi comes in 12th.

The W.H.O. rankings are based on the number of parts per million of particles smaller than 10 micrometers (PM10) floating around in the air. Even the filthiest air in the U.S., in California’s San Joaquin Valley, pales in comparison to these other cities. Ahwaz has 372 PM10, while Delhi has 198. Bakersfield, the most polluted city in the U.S., has 38.

The best cities in the U.S. for keeping your arteries free and clear? Santa Fe, New Mexico and Clearlake, California–each with a PM10 of just six. Much healthier choices for a jog the next time around.

Drought and an increased demand for water have stressed the Colorado River, which flows nearly 1,500 miles through seven states and Mexico. Photo by Flickr user Alex E. Proimos

When Alexandra Cousteau, granddaughter of Jacques, recently went to Mexico to explore the southern terminus of the Colorado River, she found mud, sand and dust where water once raged. The expedition was videotaped for a short film (viewable below) produced in conjunction with Cousteau’s nonprofit, Blue Legacy, which raises awareness about water issues. The video was called Death of a River: The Colorado River Delta.

That title, it turns out, is an apt one: Today, the conservation organization American Rivers released its annual ranking of America’s most endangered rivers, and the Colorado topped the list.

The group cites outdated water management as the main malady attacking the Colorado’s health. “A century of water management policies and practices that have promoted wasteful water use have put the river at a critical crossroads,” a statement (PDF) released by the organization reads. “Demand on the river’s water now exceeds its supply, leaving the river so over-tapped that it no longer flows to the sea.”

At one time, the river emptied into the Gulf of California, between mainland Mexico and the Baja Peninsula. In fact, this river mouth can still be found on maps, including Google’s, because it’s supposed to be there. But a recent study (PDF) conducted by the Bureau of Reclamation (a division of the U.S. Department of Interior) determined that the entire river and its tributaries are siphoned off to meet the drinking, bathing and toilet-flushing needs of 40 million Americans throughout seven states, including Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming. It also irrigates 5.5 million acres of land and helps meet the electrical-power appetite of much of the West through hydro-power facilities. Nearly two dozen Native American tribes depend on it, and it’s the centerpiece of 11 national parks, most famously the Grand Canyon.

“Growing demands on the Colorado River system, coupled with the potential for reduced supplies due to climate change may put water users and resources relying on the river at risk of prolonged water shortages in the future,” the study authors write. “Ultimately,” they add, “the Study [sic] is a call to action.”

Low water levels at the Colorado River’s Hoover Dam, on the Arizona-Nevada border. Photo by Flickr user Remon Rijper

But what action is needed? Water conservation, water reuse and water augmentation–replacing water drawn from wells–the authors say. Specifically, landowners and municipalities must boost their agricultural, municipal and industrial water conservation agendas, as well as improve their energy water-use efficiency. Solutions for the most challenging regions include finding ways to import water, reuse waste water and desalinize ocean and brackish water.

Scientists acknowledge some solutions they’ve looked into are easier said than done and that not all are viable in every region. For instance, options like importing water to Southern California via submarine pipelines, water bags and icebergs (PDF), along with watershed management techniques like weather modification (aka cloud-seeding) are a bit pie-in-the-sky.

The Colorado isn’t the only endangered river, by far. Georgia’s Flint River, the San Saba River in Texas, Wisconsin’s Little Plover River, the Catawba River in the Carolinas and Minnesota’s Boundary Waters were all also red-flagged by American Rivers this year.

The challenge for all of these rivers, including the Colorado, only grows in the future. Climate-change-induced drought is working against them. American Rivers notes (PDF) that changes to climate are expected to reduce the Colorado River’s flow by as much as 10 to 30 percent by the year 2050. It could leave yet more sand and mud behind, making parts of the American West and Southwest even more parched.

Scientists believe the absence of seed-dispersing birds is thinning the forests on the island of Guam. Photo by Isaac Chellman

Visitors to Guam’s forests find them quiet–eerily so: No chirping of birds can be heard overhead. But slithering in the shadows on the ground are snakes, each some six feet long. Brown tree snakes made their debut on Guam, the southernmost island in the Mariana Archipelago, when islanders were rebuilding after World War II. Most likely, they were stowaways in lumber shipments heading north through the Pacific Ocean from New Guinea. They quickly began feasting on the birds and small lizards they discovered in Guam’s dense forests, and–free to slither through the mountainous terrain without predators of their own–they completed an invasion of the island at a pace of one mile per year. By the late 1940s, the forests had largely fallen silent, and now, all of Guam’s native bird species are history.

Last fall, scientists from Rice University and the University of Guam published one of the first studies of the island’s extinct forest birds, which include species such as the Mariana fruit dove, Guam flycatcher and Rufous fantail. They focused on how the absence of birds has caused a spike in the spider population, which is 40 times greater on Guam than nearby islands.

Now, the researchers are turning their attention to the issue of Guam’s thinning forests—a consequence, they also believe, of the bird deficit. This summer they’ll launch a four-year study of 16 tree species, looking at how the loss of birds, which scatter seeds, is affecting tree distribution.

The brown tree snake has obliterated nearly all of Guam’s bird species since it was introduced during World War II. Photo by Isaac Chellman

The study has its roots in an a-ha moment that lead scientist Haldre Rogers recently had while conducting another seed-dispersal study in Guam’s forests. “I noticed that there seemed to be a lot of gaps [in the trees] and that the pioneer tree species–such as papaya and sumak–were difficult to find on Guam, compared to nearby islands,” she explained to Surprising Science. She discovered that there were in fact twice as many such gaps on Guam per unit area of forest. 

Pioneer trees, which are the first to appear after a disruption to the ecosystem and thrive in the full sunlight of open spaces in the forest, have small seeds that are consumed by small birds. “Without birds to move their seeds to these sunny spots in the forest, these quick-growing trees may be less likely to germinate or grow to their full size,” Rogers hypothesized.

The problem with such thinning is that it could change the structure of Guam’s forests. “There’s a concern that [they] may become filled with open areas and start to look more like Swiss cheese than a closed canopy forest,” Rogers said. In other words, what were once cool, dark forests could transform into hot, open sunny ones.

There are other possible explanations for the tree-thinning: An undiscovered forest disease could be targeting pioneer species, or mammals like pigs and deer might have a strong taste for the trees. But according to Rogers, there isn’t strong evidence to support either of these scenarios. The upcoming study will attempt to determine the cause definitively.

The Mariana fruit dove was driven to extinction by the brown tree snake on Guam and is highly endangered on other islands in the Mariana Archipelago. Photo by Isaac Chellman

To that end, the researchers will cut down individual trees in various spots within Guam’s forests, creating new gaps in the forest. They’ll also remove trees from locations on two nearby islands that are still brimming with birds. Then they’ll monitor how long it takes the spaces to fill in and take note of which seedlings thrive on Guam versus on the other islands. It may seem that to get their results they’re destroying what they’re trying to study, but in actuality they’re taking down a tiny percentage of the island’s trees–20 total.

Guam’s situation is similar to that of tropical regions worldwide. “Animals involved in seed-dispersal are in decline in a lot of tropical forests around the world right now,” the co-principal investigator of the study, Amy Dunham, said in a statement. “It’s very important to understand the implications of those declines.” So far scientists have looked into the role of endangered mammals like lemurs, giant tortoises (PDF) and African forest elephants (PDF) in seed dispersal, but the upcoming study will be one of the first to focus on endangered birds.

It’s also the rare study to examine what happens when seed dispersal completely ceases–Guam being the only place in the world to experience whole-island forest bird loss in modern times. “The situation on Guam–which is tragic–provides us with a unique opportunity to see what happens when all seed-dispersal services provided by animals are lost from an entire ecosystem,” Dunham said. 

The snakes, meanwhile, continue to dominate the island of Guam. The U.S. Department of Agriculture traps approximately 6,000 brown tree snakes each year, and yet there are still nearly two million slithering around the island. The snakiest patches contain 14,000 of the reptiles per square mile–one of the highest snake concentrations in the world.

In February, the Department of Agriculture embarked on a new tactic for tackling the snake problem: dropping dead mice laced with acetaminophen, which is fatal to them, into the jungle. ”We are taking this to a new phase,” Daniel Vice of the Department of Agriculture’s branch that focuses on wildlife services in Hawaii, Guam and other U.S. held Pacific Islands, said in a recent interview. “There really is no other place in the world with a snake problem like Guam.”

Wetlands, such as this marsh above, buffer communities against flooding. Photo by Flickr user daryl_mitchell

In the aftermath of Superstorm Sandy last fall, New York Governor Andrew Cuomo joked to President Barack Obama that New York “has a 100-year flood every two years now.” On the heels of flooding from 2011′s Hurricane Irene and Tropical Storm Lee, it certainly seemed that way. Given that climate change has sparked multiple major storms and raised sea levels, and that urban and agricultural development have impeded our natural flood-management systems, chronic flooding could be here to stay.

Wetlands, which include swamps, lagoons, marshes and mangroves, help mitigate the problem by trapping floodwaters. “Historically, wetlands in Indiana and other Midwestern states were great at intercepting large runoff events and slowing down the flows,” environmental engineer Meghna Babbar-Sebens of Oregon State University said in a recent statement. ”With increases in runoff, what was once thought to be a 100-year flood event is now happening more often.”

One key problem is that most of our wetlands no longer exist. By the time the North American Wetlands Conservation Act (PDF) was passed in 1989, more than half of the wetlands in the United States had been paved over or filled in. In some states, the losses are much greater: California has lost 91 percent of its wetlands, and Indiana, 85 percent. In recent years, scientists have been honing the art of wetlands restoration, and now a recent study published in the journal Ecological Engineering by scientists at Oregon State University is helping to make new wetlands easier to plan and design.

Scientists are using an Indiana watershed to study how wetlands can be created or restored to help stem the effects of climate change. Photo by Flickr user Davitydave

The research focused on Eagle Creek Watershed, ten miles north of Indianapolis, and identified nearly 3,000 potential sites where wetlands could be restored or created to capture runoff. Through modeling, the scientists discovered that a little wetland goes a long way. “These potential wetlands cover only 1.5% of the entire watershed area, but capture runoff from 29% (almost a third) of the watershed area,” the study authors wrote.

Their next step was to begin developing a web-based design system to allow farmers, agencies and others to identify areas optimal for new or restored wetlands and to collaborate in designing them. The recently launched system, called Wrestore, uses Eagle Creek as a test-piece.

A new web tool analyzes different components of a watershed; Indiana’s Eagle Creek Watershed steam network is pictured here. Map courtesy of Wrestore

The tool has a variety of functions: It helps identify a region’s rivers and streams, divides watersheds into smaller sub-watersheds and shows where runoff is likely to collect—places conducive to building wetlands. If a city wants to reduce flooding in its watershed, the site’s interactive visualization engine displays various conservation options and allows groups of city planners to collaborate on the design of new wetlands.

“Users can look at various scenarios of implementing practices in their fields or watershed, test their effectiveness via the underlying hydrologic and water quality models, and then give feedback to an ‘interactive optimization’ tool for creating better designs,” Babbar-Sebens, lead author of the study and the lead scientist on the web tool, told Surprising Science.

It provides an easy way for landowners to tackle such environmental challenges. “The reason we used a web-based design system is because it gives people the flexibility to try and solve their problems of flooding or water quality from their homes,” Babbar-Sebens said.

As the spring flood season approaches and environmental degradation continues throughout the nation, a new tool for mitigating wetland loss with targeted, minimal wetland gain is certainly a timely innovation. Babbar-Sebens and her team have been testing it out on Eagle Creek Watershed and will be fine-tuning it throughout the spring. ”There is a lot of interest in the watershed community for something like this,” she said.

An island of ice breaking away from Greenland’s Petermann Glacier (in the center of the photo)  in the summer of 2010. By NASA

On the morning of July 16, 2010, a hunk of ice four times the size of Manhattan cracked away from the tongue of Greenland’s Petermann Glacier and drifted to sea as the largest iceberg since 1962. Just two years later, another massive section of ice calved from the same glacier. Icebergs like these don’t stay put in the Arctic–they get picked up by currents and ushered to warmer climates, melting along the way.

According to a new study published in the journal Geophysical Research Letters, Greenland’s melting glaciers and ice caps sent 50 gigatons of water gushing into the oceans from 2003 to 2008. This comprises about 10 percent of the water flowing from all ice caps and glaciers on Earth. The research comes on the heels of a study last year that showed the ice sheets of Greenland and Antarctica are disappearing three times faster than in the 1990s, and that Greenland’s is melting at an especially accelerated rate. In the new study, scientists were able to put an even finer point to the ice-melt situation by separating out the glaciers and ice caps from the ice sheet, which blankets 80 percent of the island. What they discovered is that Greenland’s glaciers are actually melting more quickly than the ice sheet.

Studies such as these demonstrate the impacts of a warming climate on Greenland’s glaciers. But, as they say, a picture is worth a thousand words. Visual evidence of this liquefaction is captured by NASA satellites, which are able to take snapshots of calving glaciers and document longer-term ice melt. NASA displays photos of the glaciers in its State of Flux photo gallery, along with a rotating collection of satellite images that illustrate other changes to the environment, including wildfires, deforestation and urban development.

The photos, with their “now-you-see-it, now-you-don’t” quality, illustrate how glaciers are fast becoming ephemeral. Here are a few stark examples:

Greenland’s Helheim Glacier can be seen retreating and thinning from 2001 (left) to 2003 (center) to 2005 (right). By NASA 

The set of images above shows the edge of Greenland’s Helheim Glacier, located on the fringe of the Greenland Ice Sheet, as captured by a satellite in 2001, 2003 and 2005. The calving front is marked by the curved line through the valley, while bare ground appears brown or tan and vegetation is red.

According to NASA, when warmer temperatures initially cause a glacier to melt, it can spark a chain reaction that accelerates the thinning of the ice. As the edge of the glacier begins to liquefy, it crumbles, creates icebergs and eventually disintegrates. The loss of mass throws the glacier off balance, and further thinning and calving occurs, a process that stretches the glacier through its valley. Total ice volume decreases then shrinks the glacier as calving carries ice away. Helheim’s calving front stayed put from the 1970s until 2001, at which point the glacier began hasty cycles of thin, advance, and dramatic retreat, ultimately moving 4.7 miles toward land by 2005.

Greenland’s Petermann Glacier on June 26, 2010 (left) , before a massive iceberg broke away, and on August 13, 2010, after the break. By NASA

The massive calving event at Petermann Glacier in 2010 is pictured in these two images. The glacier is the white ribbon on the right side of each photo, and its tongue extends into the Nares Strait, which appears as a bluish-black stripe across the center of the right image and is heavily flecked with white chunks in the photo on the left. In the first image, the tongue of the glacier is intact; in the second, a huge chunk of ice has broken off and can be seen floating away through the fjord. This iceberg was 97 square miles in size–four times bigger than the island of Manhattan.

Greenland’s Petermann Glacier on July 16, 2012 (left and center), before a major calving event, and July 17, 2012, after an iceberg broke off. By NASA

In the summer of 2012, a second massive iceberg crumbled away from the Petermann Glacier. In these images, the glacier is the white ribbon snaking up from the bottom right. If you follow the tongue up, you’ll see that it appears intact in the photos at left and center (though the center image has an ominous crack spanning its width), which were taken the day before the calving occurred. The photo on the right shows that it crumbled as the glacier calved.

Given that Greenland experienced an exceptionally warm summer in 2012 and temperatures were higher than average this winter, 2013 is primed for more melting and massive icebergs. Last year’s ice-melt season lasted two months longer than the average since 1979, and this year’s is already off to an inauspicious start. It kicked off on March 13 with the sixth-smallest sea-ice area on record for Greenland, according to the National Snow and Ice Data Center. What will the new summer calving season bring?

Polar bear-brown bear hybrids like this pair at Germany’s Osnabrück Zoo are becoming more common as melting sea ice forces the two species to cross paths. Photo by Corradox/Wikimedia Commons

Scientists and science writers have created catchy monikers for hybrid species, much the way tabloid writers merge the names of celebrity couples (Kimye, Brangelina, anyone?). Lions and tigers make ligers. Narwhals meet beluga whales in the form of narlugas. And pizzlies and grolar bears are a cross between polar bears and grizzlies. In coming years, their creativity may get maxed out to meet an expected spike in the number of hybrids. A driving force? Climate change. 

A new study published in the journal PLOS Genetics showed that there’s a historic precedent for cross-breeding among polar bears and brown bears–we’ll jump on the bandwagon and call them brolar bears. The researchers also asserted that such hybridization is currently occurring at an accelerated clip. As sea ice melts, polar bears are forced ashore to an Arctic habitat that’s increasingly hospitable to brown bears. There have been recent sightings in Canada of the resulting mixed-breed animals, which have coloring anomalies such as muddy-looking snouts and dark stripes down their backs, along with the big heads and humped backs typical of brown bears.

As it turns out, climate-change-induced hybridization extends well beyond bears. A 2010 study published in the journal Nature listed 34 possible and actual climate-change-induced hybridizations (PDF) of Arctic and near-Arctic marine mammals–a group that has maintained a relatively consistent number of chromosomes over time, making them particularly primed for hybridization. Here are some highlights from this list, along with some more recent discoveries. 

In 2009, a bowhead-right-whale hybrid was spotted in the Bering Sea by the National Oceanic and Atmospheric Administration’s (NOAA) National Marine Mammal Laboratory. Right whales, which typically hail from the North Pacific and North Atlantic, will increasingly be migrating north into the Arctic Ocean, the domain of bowheads, as a result of climate change–and co-mingling their DNA. The authors of the Nature study determined that “[d]iminishing ice will encourage species overlap.”

The narluga has a very big head, according to the scientists who found one in West Greenland. Its snout and lower jaw were particularly burly, and its teeth shared some similarities with both narwhals and belugas. Both species, which form a whale family called monodontidae, live in the Arctic Ocean and hunters have reported seeing more whales of similar stature in the region.

Harbor and Dall’s porpoises have already been mixing it up off the coast of British Columbia, and given that harbor porpoises are likely to keep moving north from the temperate seas of the North Atlantic and North Pacific into the home waters of the Dall’s, the trend is expected to continue. (Click here to see rare photos of the hybrid porpoise.)

Scientists in Ontario, Canada, are investigating inter-breeding between southern and northern flying squirrels as the southern rodents push into northern habitats. The hybrid squirrels have the stature of the southern species and the belly coloring of the northern one. The video below details the research.

Hybrid species often suffer from infertility, but some of these cross-breeds are having success at procreating. For example, researchers recently discovered the offspring of a female pizzly and a male grizzly bear (a subspecies of the brown bear) in Canada’s Northwest Territories. Despite cases like these, scientists are debating whether all of this hybridization is healthy. “Is this going to be a problem for the long-term existence of parental species? Are they going to merge into one big hybrid population?” asked University of California, Berkeley evolutionary biologist Jim Patton in an interview.

In the case of inter-bred polar bears, the concern is that the changing climate will be more welcoming to brown bears, and that while inter-species mating at first might appear to be an adaptive technique for polar bears, it could end up spelling their demise in all ways except cellular structure–much the way Neanderthals were folded into the human gene pool thanks to early humans in Europe more than 47,000 years ago.

Rare and endangered species are particularly vulnerable to the pitfalls of hybridization, according to the authors of the Nature study. “As more isolated populations and species come into contact, they will mate, hybrids will form and rare species are likely to go extinct,” they wrote. “As the genomes of species become mixed, adaptive gene combinations will be lost.”

Such is likely the case with the narluga. Scientists determined the animal’s lack of a tusk is a liability because the tusk is a measure of the narwhal’s breeding prowess. And a pizzly living at a German zoo showed seal-hunting tendencies, but lacked the swimming prowess of polar bears.

As Patton pointed out, it will be many years until we know the full consequences of hybridization. “We’re only going to find out in hindsight,” he said. But that’s not a reason to be complacent, according to the Nature authors, who called for the monitoring of at-risk species. “The rapid disappearance of sea ice,” they wrote, “leaves little time to lose.”

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Warming oceans have caused levels of phytoplankton, like the mixed sample of single-celled and chain-forming diatoms pictured above, to decline 40 percent since 1950. Photo by Richard Kirby

Two weeks ago, a group of sailors off the coast of New Zealand leaned over the side of their boat, dropped a contraption into the Pacific Ocean and watched it disappear. Using an app they’d downloaded to a smartphone, they logged a reading from the underwater device, along with their GPS location and the water temperature. In just a few minutes’ time, they had become the first participants in a new program launched by the UK’s Plymouth University Marine Institute which allows citizen scientists to help climatologists study the effects of climate change on the oceans.

The Kiwi sailors were measuring the concentration of phytoplankton, a microorganism that lives at the sea surface. Phytoplankton, also called microalgae, produce half of the oxygen in the air we breathe and are responsible for 50 percent of the Earth’s photosynthesis. Whales, jellyfish, shrimp and other marine life feast on it, making it a critical part of the marine food chain.

Phytoplankton require a certain water temperature to thrive (this varies regionally), and without these favored conditions, they either decrease in number or migrate in search of optimal water. As the upper levels of the Earth’s oceans have warmed by 0.59 degrees Fahrenheit in the past century, the amount of phytoplankton worldwide dips by roughly 1 percent each year, according to a 2010 study published in the journal Nature

In fact, the study showed that phytoplankton concentrations have decreased by a total of 40 percent since 1950. The decline joins coral bleaching, sea-level rise, ocean acidification and a slowing of deep-water circulation (which effects water temps and weather patterns) as the known tolls of climate change on the oceans.

This drop in phytoplankton population is troubling because of this organism’s role in the marine food web. “Despite their microscopic size, phytoplankton… are harbingers of climate change in aquatic systems,” wrote the authors of a 2011 study on phytoplankton and climate change published in the journal Proceedings of the Royal Society. So understanding how other sea creatures will fare as climate changes depends on how drastically phytoplankton levels continue to drop.

The effects of a food shortage on big, open-ocean fish like swordfish and tuna, which already suffer from over-fishing, could pose problems for humans as well. “We’re squeezing [fish] from both ends,” Paul Falkowski, who runs the Rutgers University Environmental Biophysics and Molecular Ecology Lab, told Nature. “We’re overfishing the oceans for sure. Now we see there is pressure from the bottom of the food chain.”

Despite it’s importance, scientists have struggled to monitor phytoplankton, and analyzing all of the Earth’s oceans presents obvious logistical hurdles. Those challenges became apparent after one recent study concluded climate change is not to blame for dwindling phytoplankton levels and another refuted that phytoplankton is vanishing at all–igniting debate within the scientific community. Enter the Plymouth study, which is attempting to end the dispute and fill in gaps in phytoplankton research by harnessing the millions of sailors and fishermen who cruise the world’s oceans to help measure phytoplankton levels in the upper reaches of the water.

The program relies on the Secchi app, a new smartphone app devised by the Plymouth scientists that’s named for the Secchi Disk (PDF)—a piece of equipment that’s been used to measure turbidity in water since its invention in 1865 by Italian scientist Pietro Angelo Secchi. “It’s arguably the simplest item of marine sampling equipment,” Plymouth’s Richard Kirby, a plankton biologist who’s heading up the project, told Surprising Science.

Plankton biologist Richard Kirby lowers a Secchi Disk into Britain’s Plymouth Sound. Photo courtesy of Richard Kirby

When a seafaring citizen scientist is ready to use the app, the first step is to make a Secchi Disk (instructions are included). The small, white disk–made of plastic, wood or metal–is attached to a tape measure on one side and a weight on the other. You hold the tape measure and lower the disk vertically into the seawater, and as soon as it disappears from sight, you note the depth on the tape measure. This number, the “Secchi depth,” reflects the transparency of the water column, which is influenced by the number of particles present. “Away from estuaries and areas where the turbidity of the water column may be influenced by suspended sediment, the Secchi Depth is inversely related to phytoplankton biomass,” Kirby says. The Secchi depth also tells scientists the depth to which light supports life in the water.

You enter the Secchi depth and the GPS location on your smartphone (a network connection isn’t required for this) into the app. The Plymouth researchers receive the data as soon as you regain network connectivity. You can also upload photos and type in additional details like water temperature (measured by the boat) and notes on visual observations–say, a foamy surface, a plankton bloom or a flock of feeding sea birds.

A Secchi Disk submerged in Britain’s Plymouth Sound. Photo by Richard Kirby

The Plymouth researchers hope ocean-goers across the globe will participate in the research, with which they will build a database and a map of the oceans charting both the seasonal and annual changes in phytoplankton levels to help scientists studying climate change and the oceans. “One person recording a Secchi depth twice a month for a few years will generate useful data about their local sea,” Kirby says. “The more people that take part, the greater the project and the more important and valuable it will become to future generations.”

Kirby notes that citizen scientists have long provided valuable data on long-term changes to the environment, and sees the internet as big opportunity to unite the efforts of citizen scientists. “We often look back and wish we had started monitoring something about the natural world,” he says. “‘If only we had started measuring ‘x’ ten years ago.’ Well, there is no time like the present to start something for the future.”

The pollution in California’s San Joaquin Valley, including above this Norton cornfield, was tested by NASA as part of a program to monitor air quality from space. Photo by Flickr user mhall209

If you had to guess what part of the the U.S. has the very worst air pollution–where winds and topography conspire with fumes from gasoline-chugging vehicles to create an aerial cesspool–places like Los Angeles, Atlanta and as of late, Salt Lake City, would probably pop to mind. The reality may come as a bit of a surprise. According to the Environmental Protection agency, California’s bucolic San Joaquin Valley is “home of the worst air quality in the country.”

Not coincidentally, the San Joaquin Valley is also the most productive agricultural region in the world and the top dairy-producing region in the country. Heavy duty-diesel trucks constantly buzz through the valley, emitting 14 tons of the greenhouse gas ozone daily, and animal feed spews a whopping 25 tons of ozone per day as it ferments, according to a 2010 study. In addition, hot summertime temperatures encourage ground-level ozone to form, according to the San Joaquin Valley Air Pollution Control District. Pollution also streams down from the Bay Area, and the Sierra Nevada Mountains to the east help to trap all of these pollutants near the valley floor. Particulate matter that creates the thick greyish-brown smog hanging over the valley is of paramount concern–it’s been linked to heart disease, childhood asthma and other respiratory conditions.

So when NASA devised a new, five-year air quality study to help fine-tune efforts to accurately measure pollution and greenhouse gases from space, it targeted the San Joaquin Valley. “When you’re trying to understand a problem, you go where the problem is most obvious,” the study’s principal investigator, Jim Crawford, said in an interview. To Crawford, the dirty air over the valley may be important to evaluating how human activities contribute to climate change. “Climate change and air quality are really traced back to the same root in the sense that air quality is the short term effect of human impact and climate change the long term effect,” Crawford said.

In January and February, NASA sent two research planes into the skies above San Joaquin Valley to collect data on air pollution. One plane flew at high altitude over the valley during the daytime, armed with remote sensors, while the second plane cruised up and down the valley, periodically spiraling down toward the ground to compare the pollution at higher and lower altitudes. Weather balloons were used for ground-level measurements as well.

NASA deployed two airplanes to study pollution in the lowest level of the atmosphere in California’s San Joaquin Valley as part of a program to use satellites to monitor air quality and emissions. Photo by Tom Tschida/NASA

The data NASA collected in the experiment was similar to what satellites can see from space: the presence of ozone, fine particulates, nitrogen dioxide and formaldehyde (precursors to pollution and ozone) and carbon monoxide (which has a median lifetime of a month and can be used to watch the transport of pollution). But satellites are limited in their air-quality-sensing abilities. “The real problem with satellites is that they’re currently not quantitative enough,” Crawford told Surprising Science. “They can show in a coarse sense where things are coming from, but they can’t tell you how much there is.”

Nor can satellites distinguish between pollution at the ground level and what exists higher in the atmosphere. Also, they circle just once a day, and if it isn’t in the early morning, when commuters are busily burning fossil fuels, or in the late afternoon, when emissions have festered and air quality is at its worst, scientists don’t have a clear picture of just how bad pollution can get. Monitoring stations on the ground are likewise limited. They provide scientists with a narrow picture that doesn’t include the air farther above the monitoring station or an understanding of how the air mixes and moves. The research from the NASA study, specifically that collected by the spiraling airplane, fills in these gaps.

Data from the flights will also be used in conjunction with future satellites. “What we’re trying to move toward is a geostationary satellite that will stare at America throughout the day,” Crawford told Surprising Science. Geostationary satellites–which will be able to measure overall levels of pollution–can hover over one position, but like current satellites, researchers need ancillary data from aircraft detailing how pollution travels above the Earth’s surface, like that retrieved from the San Joaquin Valley, to help validate and interpret what satellites see. “The satellite is never going to operate in isolation and the ground station isn’t going to do enough,” Crawford said. 

But first, the research will be plugged into air-quality computer models, which will help locate the sources of emissions. Knowing how sources work together to contribute to poor air quality, where pollution is and exactly what levels it’s hitting is a priority for the EPA, which sets air-quality regulations, and the state agencies that enforce them, according to Crawford. The data will inform their strategies on reducing emissions and cleaning the air with minimal impact to the economy and other quality-of-life issues. “Air quality forecasts are great,” Crawford says. “But at some point people will ask, ‘Why aren’t we doing something about it?’ The answer is that we are.” The researchers have conducted similar flights over the Washington, D.C. area and are planning flyovers of Houston and possibly Denver in the years to come.

One thing’s for sure: Data to inform action is sorely needed. In 2011, Sequoia and Kings Canyon National Park, on the eastern edge of the valley, violated the EPA’s national ambient air quality standard a total of 87 days of the year and Fresno exceeded the standard 52 days. Pinpointing exactly where pollution originates and who’s responsible–a goal of the study–will go a long way to clearing the air, so to speak.

New York City is a leader in lowering greenhouse gas emissions. Photo by Flickr user Andrew C Mace

Cities are to greenhouse-gas emissions what Chernobyl was to nuclear power plant failures, which is to say, they’re the worst offenders out there. Cities consume two-thirds of the world’s energy and cough up 70 percent of global CO₂ emissions. Some are even gaining notoriety: Air pollution in Beijing is so severe these days that residents can’t even escape it by going indoors, according to scientists at Columbia University’s Earth Institute.

But many cities are making progress in shrinking their greenhouse-gas footprints, and a recent new study shows that they can make reductions of as much as 70 percent. Scientists at University of Toronto’s Civil Engineering department used Toronto as a test piece for studying cities’ carbon footprints, and they outlined how changes in transportation, buildings and energy supplies–things like boosting insulation, switching to LED lighting and putting in building management systems and automatic lighting controls–can reduce emissions.

A 30 percent reduction would be fairly simple, the researchers say. “With current policies, especially cleaning of the electricity grid, Toronto’s per-capita GHG [greenhouse gas] emissions could be reduced by 30 per cent over the next 20 years,” study author Chris Kennedy said in a statement. “To go further, however, reducing emissions in the order of 70 per cent, would require significant retrofitting of the building stock, utilization of renewable heating and cooling systems, and the complete proliferation of electric, or other low carbon, automobiles.”

Toronto has yet to begin adopting the plan Kennedy and his colleagues have outlined, but it is among the 58 city-members of the C40 Cities Climate Leadership Group, an organization committed to developing and implementing policies and practices to reduce greenhouse gas emissions. The group’s chair is New York City Mayor Michael Bloomberg, and in fact, New York is one of the most innovative and aggressive cities in the world when it comes to emissions reduction. “In my mind London and NYC are providing the greatest leadership,” Kennedy told Surprising Science.

Many other cities are also making strides, according to a 2011 study issued by C40 that details what its member-cities are doing to reduce their emissions. Forty major cities participated in the research, including Chicago, Houston, Los Angeles, Philadelphia and New York in the U.S., and cities from Moscow and Jakarta to Beijing and Mexico City internationally–many of the most populated, high-traffic urban centers in the world. Engineering and design firm Arup, along with the Clinton Climate Initiative, surveyed city officials and conducted research on their greenhouse-gas output and actions to reduce emissions.

Five cities stood out–here’s a breakdown of some highlights:

São Paulo: When landfills were reaching capacity in South America’s most populous city, the Brazilian metropolis installed thermoelectric power plants to capture and burn biogases emitted by the decaying waste. São Paulo’s 10 million citizens generate 15,000 tons of garbage each day, and trash is one of the city’s biggest greenhouse-gas challenges—as opposed to other cities, which struggle more with emissions from buildings and energy supplies. This step allowed São Paulo to reduce methane emissions and produce clean energy at the same time, and now 7 percent of the city’s electricity needs are met this way.

Copenhagen: Known for its bicycle culture, Denmark’s capital is a leader in green transportation, with 36 percent of work- or school-related commutes done by pedaling, according to the C40 study. Other cities have used Copenhagen as a model for their cycle parking, lanes, signage and other biking infrastructure. But Copenhagen is also a leader in waste management. Since 1988, it has reduced the amount of garbage it sends to landfills from 40 percent to less than 2 percent, and fully half of the city’s waste is recycled and used to generate heat. Nearly all of Copenhagen’s buildings (PDF) utilize an underground piping network that distributes hot water or steam in lieu of relying on boilers or furnaces. Citizens are required to pay for the heat regardless of whether they’re connected to the system.

Addis Ababa: In Ethiopia’s capital, shoddy water pipes are being replaced to help boost the city’s 50 percent leakage rate  “Cities can lose huge amounts of their often energy-intensively produced potable water due to leakage from pipes during distribution,” the C40 study authors wrote. “Wasting potable water… increases greenhouse gas emissions, and is also a major issue for those cities that are threatened with droughts. The number of drought-threatened cities is rising due to climate change.” 

That project joins large-scale, low-carbon housing developments that will create new homes for people currently living in Addis Ababa’s shanty towns, the C40 study showed. The city is also planning to convert 40 percent of its land to green space, which serves to absorb CO₂ emissions and reduce the urban-heat-island effect. To that end, Addis Ababa’s mayor instituted a plan to plant three million new trees (the most ambitious tree-planting project in the world) and create a giant nature reserve featuring every tree and plant native to Ethiopia. 

Ethiopia’s capital city Addis Ababa is shrinking its carbon footprint by building low-carbon, low-income housing and launching the most aggressive tree-planting program in the world. Photo by Flickr user Travlr

New York City: The city that never sleeps is a leader in green policy, according to the C40 study. Its PlaNYC, a program designed to reduce greenhouse gas emissions and otherwise prepare for climate change, includes planting trees and other vegetation to enhance 800 acres of parks and open spaces and pushing new development to areas with existing transit access so that new subway and bus lines don’t have to be added. The Greener Greater Buildings plan mandates upgrades to meet the NYC Energy Conservation Code for renovations, and the NYC Green Infrastructure Plan integrates details like green roofs and porous pavement into the city’s quest to manage storm runoff and alleviate pressure on wastewater treatment plants, which overflow in storms. New York is also known for its system of innovative pneumatic troughs that remove trash from Roosevelt Island through underground tunnels and eliminate the need for fleets of fossil-fuel-burning garbage trucks that clog traffic and wear down streets.

London: Greenhouse-gas reductions in the UK’s capital and largest city are impressive in part because it’s the only city to have achieved them “by diminishing consumption [rather] than a change of energy sources,” according to another study published last fall by Kennedy. His research showed that London was also the sole city where carbon emissions from commercial and institutional buildings have dropped. How did London make it happen? Establishing a so-called Congestion Charge Zone (PDF) was one key measure. A fee structure tied to emissions restricts the movement of freight and other heavy goods vehicles within the city’s center and allows electric vehicles to travel for free in the zone. The scheme, introduced in 2003, “has reduced vehicle numbers in the central business district by over 70,000 per day, cutting carbon emissions in the zone by 15%,” according to the study authors. Also, the city’s transit systems are integrated and easy to use thanks to a smart-ticket program, attracting more riders who might otherwise drive gas-guzzling cars.

While the overall effect of these emissions-reduction efforts hasn’t yet been measured, C40 study authors say the 40 cities have taken a combined total of 4,734 actions to tackle climate change. The simplest and most immediate change cities can make, according to Kennedy, is to decarbonize their electricity grids. “This is important because a low-carbon electricity source can be an enabler of low carbon technologies in other sectors, for example electric vehicles, or heating via ground source heat pumps,” he says. But the most effective change Kennedy recommends that city residents make in lowering their carbon footprints is to set their home thermostats 1 or 2 degrees lower in the winter or higher in the summer.

What does or could your city do to reduce its emissions? Leave us a note with your ideas!

Scientists have identified a link between global warming and extreme weather events such as heat waves. Photo by Flickr user perfectsnap

During the month of July 2011, the United States was seized by a heat wave so severe that roughly 9,000 temperature records were set, 64 people were killed and a total of 200 million Americans were left very sweaty. Temperatures hit 117 degrees Fahrenheit in Shamrock, Texas, and residents of Dallas spent 34 consecutive days stewing in 100-plus-degree weather.

For the past couple of years, we’ve heard that extreme weather like this is tied to climate change, but until now, scientists weren’t sure exactly how the two were related. A new study published yesterday in the journal Proceedings of the National Academy of Sciences reveals the mechanism behind events such as the 2011 heat wave.

What it comes down to, according to scientists at Potsdam Institute for Climate Impact Research (PIK), is that higher temperatures caused by global warming are disrupting the flow of planetary waves that oscillate between Arctic and tropical regions, redistributing the warm and cold air that usually help regulate the Earth’s climate. “When they swing up, these waves suck warm air from the tropics to Europe, Russia, or the US, and when they swing down, they do the same thing with cold air from the Arctic,” lead author Vladimir Petoukhov of PIK explained in a statement.

Under pre-global-warming conditions, the waves might have initiated a short, two-day burst of warm air followed by a rush of cooler air in Northern Europe, for example. But these days, with global temperatures having climbed 1.5 degrees Fahrenheit in the past century and escalating particularly sharply since the 1970s, the waves increasingly stall out, resulting in 20- to 30-day heat waves. 

The way it occurs is this: The greater the temperature difference between regions like the Arctic and Northern Europe, the more air circulates between the areas–warm air rises over Europe, cools over the Arctic, and rushes back down to Europe, keeping it chilly. But with global warming heating up the Arctic, the temperature gap between the regions is closing, stanching the flow of air. In addition, land masses warm and cool more easily than oceans. ”These two factors are crucial for the mechanism we detected,” Petoukhov said. “They result in an unnatural pattern of the mid-latitude air flow, so that for extended periods the… waves get trapped.”

The scientists developed models of this phenomenon and then entered daily weather data for the middle latitudes of the Northern Hemisphere during the summers from 1980 to 2012. They found that during several major heat waves and episodes of prolonged rain–which led to floods–the planetary waves had indeed been trapped and amplified.

Researchers examined the July 2011 heat wave in the U.S. for new clues on global warming and extreme weather. (Reds represent above-average temperatures and blues are lower-than-average temps.) Image via NASA Earth Observatory

“Our dynamical analysis helps to explain the increasing number of novel weather extremes,” said Hans Joachim Schellnhuber, director of PIK and co-author of the study. “It complements previous research that already linked such phenomena to climate change, but did not yet identify a mechanism behind it.”

The research joins another recent study (PDF) by scientists at Harvard that highlights how changes to air circulation patterns are spreading drought. As warm tropical air rises, it triggers rains before migrating to higher latitudes. The dry air then descends, heats up and eventually travels again, landing in regions characterized by desert. These dry regions used to be confined to narrow bands spanning the globe. But now, these bands are expanding by several degrees in latitude.

“That’s a big deal, because if you shift where deserts are by just a few degrees, you’re talking about moving the southwestern desert into the grain-producing region of the country, or moving the Sahara into southern Europe,” study author Michael McElroy said in a statement. In this way, climate change threatens national security because drought, heat and other extreme weather events can jeopardize food stocks, destroy roads and bridges, and ultimately lead to political instability, the authors note.

The connection between climate change and extreme weather will be highlighted this summer, if current trends continue. The summer of 2012 was even hotter in the U.S. than that of 2011, and according to the PIK scientists, it was also marked by prolonged, amplified waves in the mid-latitudes of the Northern Hemisphere.

Unfortunately, the frequency of these atmospheric patterns is only expected to increase. When the researchers compared the period from 1980 to 1990 with that from 2002 to 2012, they saw that the incidence of trapped waves had doubled. Bottom line: Heat waves are not only here to stay, they’ll become more frequent and will linger for longer.

Ice melt in Greenland will significantly affect water levels throughout the world, most of all the equatorial Pacific and South Africa. Photo by Christine Zenino

If you live on the coast, watch out–the shoreline close to home is moving. The planet’s two largest ice sheets, in Antarctica and Greenland, have been melting at an unprecedented pace for the past decade, and ice melt is the biggest contributor to rising sea levels. But not all coasts will draw closer inland. Scientists have determined (PDF) that water levels will rise in some parts of the world and dip in others.

Now, new research published in the journal Geophysical Research Letters and coordinated by the European organization Ice2sea shows in specific detail the effect of ice melt on sea levels by the year 2100.

Looking at Antarctica’s 15 major drainage basins and three glaciers in Greenland, the researchers relied on two ice-loss scenarios–one a mid-range melt and the other a more significant deterioration of glacial ice–and used sophisticated computer modeling to examine where and how severe the alterations in sea level would be. They keyed in on three main factors: Changes in water distribution due to the warming of the oceans; alterations in the Earth’s mass distribution that continue to occur as the crust rebounds after the last ice age, 10,000 years ago; and the fact that as glaciers melt, the Earth’s gravitational pull in the surrounding areas decreases, sending water away from the glaciers and redistributing it to other parts of the world.

What the modeling showed is that water will rush away from some polar regions and toward the equator, making the low-elevation coastal zones of the equatorial Pacific, particularly those with gently dipping shorelines, most vulnerable to rising sea levels. At the same time, water levels in some polar regions will actually drop. The total rise in the worst affected parts of the equatorial oceans could start at two feet and spike to more than three feet. This is in comparison to the six-inch sea-level rise that occurred globally in the 20th century.

In the United States, Hawaii will be hit hard. Both the moderate and more extreme ice-melt scenarios place Honolulu in the crosshairs of rising sea levels. “Honolulu is located in the broad area in the Pacific Ocean where the sea-level fingerprint is expected is expected to attain its largest… amplitude,” the authors wrote. Trouble will be brewing well before 2100, the research shows. In the latter half of the 21st century, sea levels could rise 0.32 inches per year in Hawaii, according to the more severe scenario studied.

Honolulu lies in the region that will be most affected by sea-level rise. Photo by Wally Gobetz

Other parts of the U.S. will also be affected, including the Gulf of Mexico and the East Coast, from Miami to New York City. Europe, however, will be relatively unscathed. Its close proximity to the melting ice will slow down sea-level rise. But that’s not entirely good news because it will be at the expense of greater sea-level rise in other parts.

One ramification to these rises is obvious: Coastal flooding. It’s likely that hurricanes, high seasonal waves and tsunamis will send water further inland. Also, new wetlands will be created–which sounds like a theoretical boon, but will alter surface drainage and therefore result in flooding at high tides and during heavy rainfall. In addition, coastal erosion will occur, as will the salinification of coastal groundwater aquifers, creating problems for countries like water-strapped India.

A concern the scientists have is that planners building sea walls and taking other precautionary measures are relying on outdated information. “The most reliable ‘old data’ at our disposal are those saying that sea level HAS BEEN effectively rising, on the average, by 15 to 20 cm [about six inches] during the 20th century,” the study’s lead author, Giorgio Spada of Italy’s University of Urbino, told Surprising Science in an email. “A wall of [two feet] could be enough… but we have evidence that the sea level rise is accelerating and it is ‘very likely’ that it will rise by more than 20 cm globally during the 21st century.”

Moving forward, the researchers believe that even more detailed modeling is necessary. “We need to get to a higher geographic resolution before we will really be giving planners and policy-makers what they need,” David Vaughan, program coordinator of Ice2Sea told Surprising Science. “There will be some variations in how sea-level rise changes risk between one seaside town and another 100 km [32 feet] down the coast. But we’re not in a position to advise at this level of detail.”

In the meantime, the Intergovernmental Panel on Climate Change (IPCC) is working on its fifth assessment report, a comprehensive analysis of the potential effects of climate change and suggestions for mitigating the risks. Scheduled for publication next year, it will incorporate new research–perhaps even these findings–conducted since the last report, published in 2007.

The Tigris River basin is chief among the regions in the Middle East that have suffered massive groundwater depletion in recent years. Photo by Charles Fred

Climate change, believed to have contributed to the decline of the Ottoman Empire (PDF) when drought forced villagers into a nomadic life in the late 16th century, is once again having an adverse affect on the Middle East. Precipitation has dropped off and temperatures have climbed for the past 40 years, with conditions growing especially severe in the last decade. A 2012 Yale study (PDF) showed that a drought from 2007 to 2010 so seriously stunted agriculture in the Tigris and Euphrates river basins that hundreds of thousands of people fled Iran, eastern Syria and northern Iraq.

A new study published today in the journal Water Resources Research puts an even finer point to the climate change fall-out in the Middle East: The Tigris and Euphrates river basins lost 117 million acre-feet of their stored freshwater from 2003 to 2010, an amount almost equivalent to the entire volume of water in the Dead Sea. The research, conducted by scientists at UC Irvine, NASA’s Goddard Space Flight Center and the National Center for Atmospheric Research, is one of the first large-scale hydrological analyses of the region, encompassing parts of Turkey, Syria, Iraq and Iran.

Drought typically sends water-users underground in search of aquifers, and in the midst of the 2007 water crisis, the Iraqi government, for one, did just that, drilling 1,000 wells. Such pumping has been the primary cause of recent groundwater depletion, according to the new study. Sixty percent of the lost water was removed from underground reservoirs, while dried-up soil, dwindling snowpack and losses in surface water from reservoirs and lakes exacerbated the situation. “The [groundwater storage loss] rate was especially striking after the 2007 drought,” hydrologist Jay Famiglietti, principle investigator of the study and a professor at UC Irvine, noted in a statement. Overall, the area has experienced “an alarming rate of decrease in total water storage,” he added.

Since gathering information on the ground in a region marked by such political instability isn’t very practical–or in some cases, even possible at all–the scientists instead utilized data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellites. These satellites measure a region’s gravitational pull; over time, small changes observed in the strength of this pull are influenced by factors such as rising or falling water reserves. From this, the scientists uncovered variations in water storage over much of the last decade.

The video below is a visualization of groundwater fluctuations in the Tigris and Euphrates basins using GRACE satellite imagery; blues represent wet conditions and reds are indicative of dry conditions. The drought that began in 2007 is clearly reflected.

“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.” In fact, the region is experiencing the second-fastest rate of groundwater storage loss on the planet, surpassed only by India.

Yet, demand for freshwater continues to rise worldwide, including in the U.S., where aquifer depletion is also a growing problem. Groundwater supplies in the Southwest and western Great Plains have been stressed for many years, according to the United States Geological Survey (USGS). The area surrounding Tucson and Phoenix in south-central Arizona has seen the highest drop in groundwater levels–300 to 500 feet–but other regions have also suffered. Long Island and other parts of the Atlantic coast, west-central Florida and the Gulf Coast region–notably Baton Rouge–are out of balance. And perhaps most surprisingly, the Pacific Northwest is experiencing groundwater depletion as a result of irrigation, industrial water use and public consumption.

According to study co-author Matt Rodell of NASA, such depletion is unsustainable. “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.”

What’s to be done? More research, according to the authors of the new Middle East study. “The opportunity to construct the most accurate and holistic picture of freshwater availability, for a particular region or across the globe, is now on us,” they wrote. “Such science-informed studies are essential for more effective, sustainable, and in transboundary regions, collaborative water management.” Building on that last point, they called for international water-use treaties and more consistent international water laws.

They will also spread word of their findings by traveling to the Middle East. Famiglietti and three of his UC Irvine colleagues, including the study’s lead author, Katalyn Voss, are heading to Israel, Palestine and Jordan tomorrow to share their data with water authorities, scientists, water managers and NGOs; verify the GRACE measurements with locally obtained data; and begin collaborating with local groups on hydrology and groundwater-availability research.

They hope to educate themselves on the region’s best practices for water efficiency, with the goal of introducing those techniques to other water-strapped areas, including California. “Ideally, this trip will set the foundation for future research collaborations in the region, with universities and government agencies, as well as provide an opportunity for cross-regional learning between California and the Middle East,” Voss told Surprising Science.

The Indian Peafowl may need help adapting to climate change. Photo by Sergiu Bacioiu

In the coming years, the birds of Asia’s Eastern Himalaya and Lower Mekong Basin, considered biodiversity hotspots by scientists, will need to relocate within the region to find viable habitat, according to a new study published in the journal Global Change Biology. The reason? Climate change. Researchers at England’s Durham University tested 500 different climate-change scenarios for each of 370 Asian bird species and found that every possible climatic outcome–even the least extreme–would have an adverse effect on the birds.

The researchers honed in on sensitive habitat in Bhutan, Laos, Cambodia, Vietnam and parts of Nepal and India, where development and population growth are occurring at a rapid clip and the effects of climate shifts are expected to be significant, with both wet and dry seasons intensifying. Portions of the region will suffer drastically, the study authors wrote, and certain climates will have “no present-day analogues” by 2100.

This will send birds in search of food. “Food availability [could become] more seasonal, meaning that in some periods there is an over-abundance of food, in others the birds starve,” lead author Robert Bagchi, formerly of Durham University and now a senior scientist at ETH Zürich, told Surprising Science. Species in the Lower Mekong Basin, which includes Laos, Cambodia and Vietnam, will be most vulnerable to these shifts.

In the most extreme cases, the research showed, birds will need to be physically relocated–an outcome scientists are hoping to avoid. Instead, they’re recommending proactive conservation. “Maintaining forest patches and corridors through agricultural landscapes is likely to be a far more effective and affordable long term solution than translocation,” Bagchi said. Linking bird habitat will be key so that species can move between sites that are currently viable and those that will suit them in the future.

The ramifications of bird relocation on plants and other animals has yet to be examined, but the shifts likely won’t bode well. Plant species that rely on birds to disperse seeds may not be able to survive, according to Bagchi. “Understanding how species interactions are going to change is very much at the cutting edge of what ecologists are trying to understand at the moment,” he said.

The study joins a growing body of research into how changes in climate affect food and water supplies, ranges, breeding habits and life cycles for birds and a variety of wildlife. Among those studied and deemed at risk are California’s threatened and endangered bird species. Research published last year showed that sea-level rise and changes in precipitation will most seriously imperil wetlands birds.

Investigators with the National Science Foundation are currently studying the prospects of Antarctica’s Adélie penguins for surviving climate change; the birds rely on floating sea ice, and if warmer temperatures melt that ice, the penguins will vanish. The top swimmers and foragers among their ranks have the best chances of survival, according to researchers, whose work is detailed in this video.

Scientists in Antarctica are studying how climate change is affecting Adélie penguins. Photo by Penguinscience.com

Among mammals, the adverse impacts of global warming on polar bear habitat has been well documented. A 2011 study showed the bears must swim longer distances in search of stable sea ice and that cubs are 27 percent more likely to die as a result of the extended plunges. New research published in the journal Ecology reveals that elephants are also vulnerable: Higher temperatures and lower precipitation have created an acute threat to Myanmar’s endangered Asian elephants, particularly babies.

Land-dwelling North American animals have also been affected. The snowmelt required by wolverines for reproduction is so greatly diminished that federal wildlife officials nominated the animal for Endangered Species Act listing earlier this month. And climate-change-induced, late-spring snowfalls have caused the Columbian ground squirrel to extend its Rocky Mountains hibernation by ten days over the past 20 years, according to Canadian researchers. By emerging later, the animals lose valuable time to stock up on the food they need to survive the next winter.

Conversely, another hibernator, the yellow-bellied marmot, was shown in a 2010 study to actually thrive in the face of climate alterations–a phenomenon scientists attributed to earlier-spring plant growth. But they predicted the benefits would be short-lived due to an increasingly serious climatic pitfall: drought.

Meanwhile, as temperatures continue to rise, other wildlife and insects are expected to flourish outright, including certain invasive species that will be able to expand their ranges and survive winters in new places, as well as non-invasive species. A recent Discovery news article highlighting climate-change winners focused on the brown argus butterfly, which has found a new host plant and a larger range; the albatross, whose food-finding ability has gotten a boost from shifting wind patterns; and the Australian gray nurse shark, whose population could boom if warmer waters reunite two separate populations. Also, melting Arctic ice could provide new feeding opportunities for orcas–but if so, two species it preys on, belugas and narwhals, would move into the climate-change losers column.

Using new technology, scientists can study how infestations by insects like the western spruce budworm play a role in climate change. Photo by Paul Williams

It’s become a destructive cycle in the western U.S.: Warmer temperatures and drought conditions prolong the life cycle of mountain pine beetles, allowing them to prey on the pine, spruce and fir trees that blanket the mountains. The trees turn reddish-brown before dying off–a phenomenon the National Park Service deemed “an epidemic stretching from Canada to Mexico.” There’s widespread concern that such tree mortality creates an excellent fuel source for wildfires.

Until recently, scientists were left to survey the damage from the ground, with little ability to understand the causes and processes. But now new technology is enabling them to use satellite imagery to identify the sources of small, ecosystem-altering events–some of which, for example beetle outbreaks, are related to climate change drivers. A computer program called LandTrendr, developed by Boston University Earth and Environment professor Robert Kennedy, allows scientists to combine data they collect on the ground with satellite imagery from the U.S. Geological Survey (USGS) and NASA to get a better understanding of environmental disturbances.

Since 1972, NASA and the USGS have deployed satellites that snap specialized digital photographs of Earth’s landscapes. They’re able to capture details that exist in wavelengths invisible to the human eye, including those slightly longer than visible light called the near infrared. Healthy plants reflect energy in the near infrared, and by scanning the imagery, scientists can detect disruptions in Earth’s landscapes.

In the past, these images were prohibitively expensive, limiting scientists’ access. “We’d look at an image from 2000 and one from 2005 and ask, ‘What’s changed?’” Kennedy explained. “If you’re only looking at two images, it’s very difficult to track slowly evolving changes. You can tell something’s changed, but you don’t know how long it’s taken.”

When the USGS began providing these images for free in 2008, it was a turning point for Earth scientists. They now had access to thousands of shots of any given geographic region–images that Kennedy’s LandTrendr tool utilizes. “By looking at all the images, you can watch [changes] unfold. You have more confidence that you’re actually seeing trends,” he said. This is particularly useful for understanding climate change and land use change, which are “all about process,” according to Kennedy.

Kennedy is currently using LandTrendr technology to look at the net carbon exchange of forests; among other things, his work analyzes the amount of carbon lost in forests due to fire, clear cuts, partial cuts and urbanization. Studies of climate change in the Arctic and in transition zones between ecosystems are also utilizing LandTrendr. But in the Pacific Northwest, Garrett Meigs, a forestry PhD candidate at Oregon State University, is using LandTrendr to study the intersection of wildfire and insects.

Specifically, Meigs is examining the large wildfires that have ravaged Washington and Oregon since 1985, and how outbreaks of the mountain pine beetle and western spruce budworm affect subsequent fire activity. “When there’s drought, stress, a higher susceptibility to infestation, we can see the dieback of forest,” he said.

The LandTrendr algorithm incorporates satellite images of the regions affected by fire and bugs with Meigs’ own fieldwork and historical aerial data from the U.S. Forest Service, which has long used airplanes to survey insect infestations. “There were things we couldn’t detect or see before, but now we’re able to,” Meigs said.

Below is a video showing a LandTrendr visualization of the Pacific Northwest. Kennedy explains how it works: Stable evergreen forests are represented by the blue areas; when a mountain pine beetle infestation erupts, in this case in the Three Sisters area of Oregon, the imagery glows red. And when a slow-moving western spruce budworm moves into an area–there, the southern foothills of Mount Hood–it morphs yellow.

Could LandTrendr help predict climate change? Possibly. “We can’t see the future, we can only document with the satellites what has happened. But the whole game with science is to develop understandings that allow for prediction,” Kennedy says. “My hope is that by creating these maps and capturing these processes in ways we haven’t been able to see them before, we can test [climate change] hypotheses” by documenting where, when and if predicted effects occur, he said.

While Meigs’ study of insects and wildfire is largely retrospective, it has the potential to aid in future forecasting efforts. “We have a baseline to measure future change,” he says. “By seeing the conditions leading up to big insect outbreaks or wildfires, we may be able to recognize them as they emerge in the future.”

A new study shows that dispersing minerals into oceans to stem global warming would be an inefficient and impractical process. By Kent Smith

Installing a giant mirror in space to block sunlight, dispersing mass quantities of minerals into the oceans to suck carbon dioxide from the air and infusing the Earth’s upper atmosphere with sun-reflecting chemicals might sound like the stuff of science fiction, but they’re actual techniques that have been contemplated by scientists as possible quick solutions to climate change. More specifically, they’re examples of geo-engineering, a hotly contested subset of climate science whereby the Earth’s environment is intentionally manipulated in order to mitigate the effects of global warming.

Since cutting greenhouse gas emissions has been something of an exercise in futility, the idea behind geo-engineering is to put systems in place that manage the carbon dioxide that’s already emitted into the atmosphere. The two basic methods are solar radiation management—whereby a small amount of the sun’s heat and light is reflected back into space—and carbon dioxide removal, which involves the capture of CO2 or its uptake by the oceans.

A new study published yesterday in the journal Environmental Research Letters poked holes in one proposed approach to carbon dioxide removal. The research, conducted by scientists from Germany’s Alfred Wegener Institute for Polar and Marine Research, showed that dissolving the mineral olivine into the oceans would be an inefficient way of reducing atmospheric carbon dioxide.

The researchers used computer modeling to study six scenarios of dissolving olivine into the oceans—a process that increases the alkalinity of the water, which in turn allows the seas to absorb more carbon dioxide from the atmosphere. The results revealed the following limitation: Dispersing three gigatons (equal to three billion tons) of olivine into the oceans compensated for just roughly nine percent of the planet’s current CO2 emissions. To do the entire job would require 40 gigatons–an excessively large amount of the mineral.

Crushing all of that rock into a fine-enough powder for it to easily dissolve would present another set of environmental problems, according to the researchers. “[E]nergy costs of grinding olivine to such a small size suggest that with present day technology, around 30 per cent of the CO2 taken out of the atmosphere and absorbed by the oceans would be re-emitted by the grinding process,” the lead author of the study, Peter Köhler, said in a statement.

“If this method of geoengineering was deployed, we would need an industry the size of the present day coal industry to obtain the necessary amounts of olivine,” Köhler added. Olivine is found beneath the Earth’s surface. To distribute such a large quantity of it would require a fleet of 100 large ships.

The researchers also concluded that mass dissolution of olivine would have a few side effects. Iron and other trace metals would be released into the seas, which would result in ocean fertilization, a process that can spark plankton blooms. On the flip side, ocean acidification, another climate change woe, would actually improve with olivine dissolution. The rise in alkalinity would counteract ocean acidification.

But overall, the process would be far from a quick cure-all. “The [world’s] recent fossil emissions… are difficult if not impossible to be reduced solely based on olivine dissolution,” the researchers wrote. “It certainly is not a simple solution against the global warming problem,” Köhler added.

This study aside, many scientists have debated the merits of geo-engineering. Some are skeptical that greenhouse gas emissions will ever be effectively reduced and they see solar radiation management and carbon dioxide removal as viable alternatives. “People worry that if we use geoengineering, we wouldn’t reduce our greenhouse gas emissions,” Scott Barrett, a professor of natural resource economics at Columbia University, said in an interview published on the school’s Earth Institutes blog. “But we’re not reducing them anyway… And given that we have failed to address climate change, I think we’re better off having the possibility of geoengineering.”

Others disagree. “There’s no reason to think it’s going to work,” environmental activist and author Bill McKibben said in a recent interview with The Rumpus. “The side effects will probably be worse than the disease. And none of the things anyone’s talking about doing will do anything about the way we are destroying the ocean, which, even if nothing else was happening, would be enough to get off fossil fuels immediately.”