Authors of the paper, led by , a UW research scientist in atmospheric sciences, set out to examine observations collected from weather stations around the world as a way to study the distribution of clouds. The research was recently published in the American Meteorological Society’s .

Among the many reasons that scientists study clouds are that cloud properties are expected to change with global warming and clouds have an impact on temperature and rainfall.

Eastman and co-author , a UW professor of atmospheric sciences and of Earth and space sciences, found that from 1971 through 2009 cloud cover over land globally declined 0.4 percent per decade. That’s less of a decline than the 0.7 percent per decade that the pair found in a 2007 paper that examined data from 1971 through 1996.

Because scientists would need to examine much more data about changes in types of clouds at different altitudes at different locations in different seasons, it’s difficult to ascertain how important this change in cloud cover over land is.

鈥淲e do expect global cloud cover to respond to climate change, but this trend alone cannot be directly linked as a cause or result of global warming,鈥� Eastman said.

The research was based on visual observation that doesn’t include information about important changes to cloud features like thickness or the ability to reflect light.

Visual observations do, however, shed light on some notable changes in cloud distribution.

For instance, the researchers found a significant poleward shift in the cloud cover associated with the mid-latitude storm track, often described as the jet stream, as well as a shift poleward in the dry, cloud-free areas over the subtropical deserts.

“Since these clouds are associated with the jet stream, it indicates the jet stream is also moving poleward,” Eastman said. “This supports other findings that the tropics are expanding with the shift in the jet stream.”

In 2006, UW scientists were the first to that the jet stream was shifting, leading to an expansion of the world’s driest regions.

In their research, Eastman and Warren also discovered significant changes in clouds over Northern India that are consistent with a drying trend there. They found an increasing incidence of stratiform clouds and fewer cumuliform clouds. Stratiform clouds are low, horizontal clouds that form in sheets. They tend to produce light rain or drizzle and are less likely to produce heavy rain than cumuliform clouds, which are distinct, vertical clouds created by warm, moist air rising in turbulent updrafts.

The change could be caused by heavy pollution containing large amounts of black carbon in the area. Black carbon absorbs sunlight, creating a warming effect aloft while reducing the amount of sunlight that reaches the surface, cooling it. That stabilizes the atmosphere, creating an environment more conducive to the formation of stratiform than cumulonimbus clouds.

“We saw a shift in cloud types in this area, which supports models that show that pollutants are causing this change in the way clouds form and on precipitation,” Eastman said.

In northeastern China, which like India has also experienced droughts along with a large increase in pollution, the researchers were unable to identify a similar pattern. Instead, they found that the area is experiencing a slight decline in both cumuliform and stratiform clouds.

Eastman and Warren hope to continue analyzing the observations.

“Our goal is to keep this going so we can verify satellite measurements and support modelers in their work,” Eastman said.

The researchers face some challenges though.

“There are more than 100 countries, thousands of observers and millions of data points,” Eastman said. “You’re going to see some problems.”

For example, they detail anomalies they found with data from weather stations in Russia that appeared to show a dramatic change in clouds over some areas. When they examined data on other kinds of clouds observed from the same stations, they found that those clouds didn’t substantially change, which they regard as unlikely. The researchers also noticed that the dramatic changes in observed clouds occur in different years at different stations.

“We have not identified the cause for the spurious changes in cloud types shown here. It is most likely the result of an undocumented change in observing procedure or training at some stations,” they wrote in the paper.

Eastman and Warren also face a possible reduction in the overall volume of data they are able to collect. Some regions of the world, like the U.S. and Canada, are switching from human observations to machine observations.

“The data set has to be homogeneous,” Eastman said. That means the pair can’t incorporate data from North America in their reports.

The research was supported by the National Science Foundation.

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For more information, contact Eastman at 206-543-7180 or rmeast@atmos.washington.edu

Average total rainfall in the area for August is about a half-inch. During this 24-hour period more than 8 inches fell, causing severe damage and leaving 193 dead, hundreds missing and thousands homeless.

“Flash flooding events don’t happen often but when they do they are some of the scariest, most dangerous and quickest natural disasters that can happen,” said , a 天美影视传媒 graduate student in . “But now that we know what types of conditions to look out for, flash flood warnings in remote regions of India might be possible.”

Rasmussen and , a UW professor in atmospheric sciences, studied satellite images and what’s called re-analysis data to piece together what happened to create such a torrential downpour. Their conclusions 鈥� including that the flash flood was set off by a string of unusual weather events not unlike those that caused devastating flash floods in Colorado and South Dakota in the 1970s 鈥� appear in the Nov. 14 Bulletin of the American Meteorological Society.

They found that on three consecutive days clouds formed high in the mountains to the east over the Tibetan Plateau. By itself, that isn’t uncommon, Rasmussen said.

“What’s different in this case is that there was the unusual wind coming from the east and blowing west,” she said. That helped the clouds clump together and build into a larger storm system capable of creating heavy rain over Leh, which is 11,480 feet above sea level.

At the same time, low-level winds carried in moisture from both the Bay of Bengal and the Arabian Sea. “The storm, forming just up the slope, was able to tap into that additional moisture,” she said.

Typically, such large storm systems don’t have the chance to build because each day as the sun sets, the warm air that has helped the clouds form and lift gets cooler. The clouds then die out in the evening. But during those three days of August 2010, the unusual wind blew through the night, spurring the clouds to continue building into a system capable of heavy rain.

Above-average rain fell on the first two days. Since the region typically gets so little rainfall, the soil doesn’t absorb water well.

“The key is that this happened for three successive days. If the third day hadn’t happened or if the first two days hadn’t set the process in motion, there probably wouldn’t have been such a devastating flash flood,” Rasmussen said.

The situation is reminiscent of weather that caused deadly flooding through the Big Thompson Canyon in Colorado in 1976 and the Black Hills of South Dakota in 1972. In all three cases, large organized clouds gathered high in the mountains and drew moisture up the slope of the mountain into the storms.

The resulting heavy rains are uncommon in mountains, where there typically isn’t enough moisture to cause such dramatic rain. They are also more dangerous than storms in the plains, where water can spread more evenly. In the mountains, the water is funneled into valleys where it accumulates into a narrow space and can form a flash flood.

“A flash flooding-type storm could be moved out onto the plains and simply cause rain across a wide area. But in the right place at the wrong time it can be devastating,” Rasmussen said.

Now that researchers have identified these common elements, including organized clouds high in the mountains on the edge of an arid plain with unusual access to moisture, weather forecasters can potentially warn people who could be in danger if a flash flood happens, she said.

There were some differences between the U.S. floods and the Leh incident. For instance, in the U.S., the storms didn’t move very much. In Leh, for three days the storms moved along the Tibetan plateau but all the rain funneled into the valley where Leh is situated.

In addition to viewing satellite images, Rasmussen and Houze examined data created by using observations of actual conditions to adjust forecasts in retrospect. This re-analysis data included information collected from surface measurements and weather balloons that track things like pressure patterns and moisture in the region. The researchers also recently completed a high-resolution modeling study confirming the findings in the paper.

The National Science Foundation and NASA funded the research.

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For more information, contact Rasmussen at kristen@atmos.washington.edu or Houze at 206-543-6922 or houze@uw.edu.

It’s all part of a new partnership that has evolved since disappearing Arctic ice has opened vast new frontiers 颅颅鈥� for the Coast Guard and for 天美影视传媒 scientists.

This year, the lowest ebb of Arctic sea ice covered less area than at any time since scientists began recording it. From 1979 to 2000, the average low point for the year was 7 million square kilometers, or 2.7 million square miles. This year, it’s less than half as much 鈥� 3.4 million square kilometers.

“It used to be that the ice just pulled back a bit from the beach each year,” said , an oceanographer at the UW’s . “Now we’re seeing huge areas of open water.”

Suddenly faced with a great expansion of the water over which it must monitor ship traffic and perform search-and-rescue operations, the Coast Guard has begun making regular flights over the Arctic, taking off from Kodiak, Alaska. UW researchers, equally eager to explore the newly accessible ocean, are among those who have tagged along on regular Coast Guard flights, known as Arctic Domain Awareness flights,聽 to deploy scientific equipment.

The UW is leading a project known as the that aims to take repeated ocean, ice and atmospheric measurements in the Beaufort and Chukchi Seas, north and west of Alaska.

Researchers are able to arrange for deployment of equipment to take those measurements via the Coast Guard’s scheduled C-130 Hercules aircraft tours. They have flown monthly this summer, with Coast Guard crews deploying 19 probes as far as 80 degrees north latitude, north of most land masses. The final flight will be in mid-October, after which it gets too dark to travel very far and the ice returns.

The researchers are studying the impact of the lack of ice cover. For instance, ocean surface temperature can be 5 or 6 degrees warmer without ice. Because there’s no ice to block solar radiation, the layer of warmer water extends deeper and that affects circulation patterns and slows the growth of ice during the winter. Changes in the ocean surface temperatures can also have profound effect on the atmosphere and changes in the temperature, humidity and cloud cover can in turn affect how fast sea ice melts or grows.

“For the first time we’re measuring ocean and atmosphere in an integrated way and trying to track the changes,” said , a climatologist and chair of the Applied Physics Laboratory’s Polar Science Center.

UW scientists involved with the , designed to monitor sea level pressure, surface air temperature and ice motion, have also taken advantage of the Coast Guard flights. The multiagency program is led by the UW’s Polar Science Center and has deployed hundreds of buoys in the Arctic since 1979.

The researchers have modified some equipment so it can be tossed out of airplanes rather than deployed by ship. One large buoy used by the International Arctic Buoy Program carries instruments that transmit air temperature and pressure information via satellite and gets rolled out of the back of the airplane flying 300 feet above the surface. At that height, a parachute fills and releases in time to temper the buoy’s landing. If the buoy is dropped from higher it might hit too hard, damaging the instruments; too low and the parachute may drag the buoy sideways in the water. The researchers have learned about both issues the hard way.

Coast Guard crews have also been deploying 3-foot-long, tube-shaped instrument packages out the side door of the planes. Once the package hits the water, it drops a torpedo-shaped sensor probe that travels to a depth of 1,000 meters, or 3,280 feet, in about 10 minutes. The probe is connected by a thin copper wire to a radio transmitter that floats on the surface. The probe sends data about water temperature and salinity up the thin wire to the surface transmitter, which relays it by VHF radio back to the airplane circling above.

Without the planes, the researchers would have to hire a ship, usually an icebreaker, to bring the instruments to the targeted location. Or, they could pay for a specialized research aircraft, an expensive proposition, particularly for research that benefits from weekly or monthly expeditions. “You won’t get that kind of repeat coverage with a designated research aircraft,” Schweiger said.

The Coast Guard appears to get some value from taking the scientists along too. Data from the buoys about air pressure and temperature is fed into the world meteorological network. “This weather data helps them fly safely,” said , a mathematician at the Applied Physics Laboratory who coordinates the International Arctic Buoy Program.

The scientists can also field questions from the crew about ice thickness and the weather in the area, Morison said.

The data they collect is already being used by many institutions as well, including the , which closely monitors Arctic sea ice.

The researchers hope to be able to continue their collaboration with the Coast Guard in years to come.

The Seasonal Ice Zone Reconnaissance Surveys program is funded by the Office of Naval Research and the International Arctic Buoy Program is funded by the 20 research and operational institutions that comprise the program.

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For more information, contact Schweiger at axel@apl.washington.edu or 206-543-1312.

While many oceanographers set out specifically hoping to avoid rough seas, Thomson, who studies large waves, is chasing them. He and his team are preparing to visit Station P, one of the oldest oceanographic research sites, located more than 1,000 miles offshore. Instruments there have measured waves more than 33 feet high.

Thomson, who is also an assistant professor of civil and environmental engineering, and his team will be deploying new buoys that measure waves and retrieving an old one — if its battery doesn’t die before they reach it. They’ll also use balloons in the air and instruments mounted to the research vessel to measure many aspects of the rough seas.

The Scientist at Work blog features researchers setting out on expeditions around the world, offering them an opportunity to give readers an inside glimpse into the life of a scientist in the field. The New York Times describes the blog as “the modern version of a field journal, a place for reports on the daily progress of scientific expeditions — adventures, misadventures, discoveries.”

Thomson’s appeared today and describes the last minute scramble to prepare for the expedition, which unexpectedly will depart four weeks earlier than initially planned. 聽Keep an eye on the blog in the coming weeks to follow along on the adventure.

The ringed seal, currently under listing, builds caves to rear its young in snow drifts on sea ice. Snow depths must be on average at least 20 centimeters, or 8 inches, to enable drifts deep enough to support the caves.

“It’s an absolute condition they need,” said , an associate professor of atmospheric sciences at the 天美影视传媒. She’s a co-author of the study, published in the journal .

But without sea ice, the platform that allows the snow to pile up disappears, ultimately reducing the area where the seals can raise their pups.

Bitz typically focuses on studying the area and thickness of sea ice. “But when a seal biologist telephoned and asked what our climate models predict for snow depth on the ice, I said, ‘I have no idea,'” she said. “We had never looked.”

That biologist was co-author Brendan Kelly of the National Science Foundation and he was curious about the snow depth trend because he was contributing to a governmental report in response to the petition to list the seals as threatened.

The researchers, including lead author and UW atmospheric sciences graduate student , found that snowfall patterns will change during this century but the most important factor in determining snow depth on the ice will be the disappearance of the sea ice.

“The snowfall rate increases slightly in the middle of winter by the end of the century,” Hezel said. However, at the same time sea ice is expected to start forming later in the year than it does now. The slightly heavier snowfall in the winter won’t compensate for the fact that in the fall — which is also when it snows the heaviest — snow will drop into the ocean instead of piling up on the ice.

The researchers anticipate that the area of the Arctic that accumulates at least 20 centimeters of snow will decrease by almost 70 percent this century. With insufficient snow depth, caves won’t hold up.

Other climate changes threaten those caves, too. For instance, the snow will melt earlier in the year than it does now, so it’s possible the caves won’t last until the young seals are old enough to venture out on their own. In addition, more precipitation will fall as rain, which soaks into the snow and can cause caves to collapse.

The research is important for more than just the ringed seals. “There are many other reasons to study snow cover,” Hezel said. “It has a huge thermodynamic impact on the thickness of the ice.”

Snow on sea ice in fall and winter acts like a blanket that slows the release of heat from the relatively warm ocean into the atmosphere. That means deeper snow tempers sea ice growth.

In the spring, snow has a different impact on the ice. Since snow is more reflective than ice, it creates a cooling effect on the surface. “So the presence of snow helps sustain the icepack into spring time,” Hezel said.

To produce the study, the scientists examined 10 different climate models, looking at historic and future changes of things like sea ice area, precipitation, snowfall and snow depth on sea ice. The resulting prediction for declining snow depth on sea ice this century agreed across all of the models.

The new research comes too late to be cited in the about ringed seals that was written by the National Oceanic and Atmospheric Administration in response to the petition to list the ringed seal as threatened. However, it confirms results that were based on a single model that Bitz provided for the report two years ago. NOAA expects to soon.

The UW scientists on this study were funded by the Office of Naval Research.

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For more information, contact Hezel at phezel@atmos.washington.edu or 206-321-5737 or Bitz at 206-543-1339, bitz@atmos.washington.edu.

atmospheric physicist describes a possible way to run an experiment to test the concept on a small scale in a comprehensive paper published this month in the journal .

The point of the paper — which includes updates on the latest study into what kind of ship would be best to spray the salt water into the sky, how large the water droplets should be and the potential climatological impacts — is to encourage more scientists to consider the idea of marine cloud brightening and even poke holes in it. In the paper, he and a colleague detail an experiment to test the concept.

“What we’re trying to do is make the case that this is a beneficial experiment to do,” Wood said. With enough interest in cloud brightening from the scientific community, funding for an experiment may become possible, he said.

The theory behind so-called marine cloud brightening is that adding particles, in this case sea salt, to the sky over the ocean would form large, long-lived clouds. Clouds appear when water forms around particles. Since there is a limited amount of water in the air, adding more particles creates more, but smaller, droplets.

“It turns out that a greater number of smaller drops has a greater surface area, so it means the clouds reflect a greater amount of light back into space,” Wood said. That creates a cooling effect on Earth.

Marine cloud brightening is part of a broader concept known as geoengineering which encompasses efforts to use technology to manipulate the environment. Brightening, like other geoengineering proposals, is controversial for its ethical and political ramifications and the uncertainty around its impact. But those aren’t reasons not to study it, Wood said.

“I would rather that responsible scientists test the idea than groups that might have a vested interest in proving its success,” he said. The danger with private organizations experimenting with geoengineering is that “there is an assumption that it’s got to work,” he said.

Wood and his colleagues propose trying a small-scale experiment to test feasibility and begin to study effects. The test should start by deploying sprayers on a ship or barge to ensure that they can inject enough particles of the targeted size to the appropriate elevation, Wood and a colleague wrote in the report. An airplane equipped with sensors would study the physical and chemical characteristics of the particles and how they disperse.

The next step would be to use additional airplanes to study how the cloud develops and how long it remains. The final phase of the experiment would send out five to 10 ships spread out across a 100 kilometer, or 62 mile, stretch. The resulting clouds would be large enough so that scientists could use satellites to examine them and their ability to reflect light.

Wood said there is very little chance of long-term effects from such an experiment. Based on studies of pollutants, which emit particles that cause a similar reaction in clouds, scientists know that the impact of adding particles to clouds lasts only a few days.

Still, such an experiment would be unusual in the world of climate science, where scientists observe rather than actually try to change the atmosphere.

Wood notes that running the experiment would advance knowledge around how particles like pollutants impact the climate, although the main reason to do it would be to test the geoengineering idea.

A phenomenon that inspired marine cloud brightening is ship trails: clouds that form behind the paths of ships crossing the ocean, similar to the trails that airplanes leave across the sky. Ship trails form around particles released from burning fuel.

But in some cases ship trails make clouds darker. “We don’t really know why that is,” Wood said.

Despite increasing interest from scientists like Wood, there is still strong resistance to cloud brightening.

“It’s a quick-fix idea when really what we need to do is move toward a low-carbon emission economy, which is turning out to be a long process,” Wood said. “I think we ought to know about the possibilities, just in case.”

The authors of the paper are treading cautiously.

“We stress that there would be no justification for deployment of [marine cloud brightening] unless it was clearly established that no significant adverse consequences would result. There would also need to be an international agreement firmly in favor of such action,” they wrote in the paper’s summary.

There are 25 authors on the paper, including scientists from University of Leeds, University of Edinburgh and the Pacific Northwest National Laboratory. The lead author is John Latham of the National Center for Atmospheric Research and the University of Manchester, who pioneered the idea of marine cloud brightening.

Wood鈥檚 research was supported by the UW College of the Environment Institute.

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For more information, contact Wood at 206-543-1203 or robwood2@u.washington.edu

When averaged, the predictions have come in remarkably close to the mark in the past two years. But the low and high predictions are off by hundreds of thousands of square kilometers.

Researchers are working hard to improve their ability to more accurately predict how much Arctic sea ice will remain at the end of summer. It’s an important exercise because knowing why sea ice declines could help scientists better understand climate change and how sea ice is evolving.

This year, researchers from the ‘s are the first to include new NASA sea ice thickness data collected by airplane in a prediction.

They expect 4.4 million square kilometers of remaining ice (about 1.7 million square miles), just barely more than the 4.3 million kilometers in 2007, the lowest year on record for Arctic sea ice. The median of collected by the Sea Ice Outlook and released on Aug. 13 is 4.3 million.

“One drawback to making predictions is historically we’ve had very little information about the thickness of the ice in the current year,” said , a climatologist at the Polar Science Center, a department in the UW’s .

To make their prediction, Lindsay and , an oceanographer in the Polar Science Center, start with a widely used model pioneered by Zhang and known as the . That system combines available observations with a model to track sea ice volume, which includes both ice thickness and extent.

But obtaining observations about current-year ice thickness in order to build their short-term prediction is tough. NASA is currently in the process of designing a new satellite that will replace one that used to deliver ice thickness data but has since failed. In the meantime, NASA is running a program called that uses airplanes to survey sea ice as well as Arctic ice sheets.

“This is the first year they made a concerted effort to get the data from the aircraft, process it and get it into hands of scientists in a timely manner,” Lindsay said. “In the past, we’ve gotten data from submarines, moorings or satellites but none of that data was available in a timely manner. It took months or even years.”

There’s a shortcoming to the IceBridge data, however: It’s only available through March. The radar used to measure snow depth on the surface of the ice, an important element in the observation system, has trouble accurately gauging the depth once it has melted and so the data is only collected through the early spring before the thaw.

The UW scientists have developed a method for informing their prediction that is starting to be used by others. Researchers have struggled with how best to forecast the weather in the Arctic, which affects ice melt and distribution. “Jinlun came up with the idea of using the last seven summers. Because the climate is changing so fast, only the recent summers are probably relevant,” Lindsay said.

The result is seven different possibilities of what might happen. “The average of those is our best guess,” Lindsay said.

Despite the progress in making predictions, the researchers say their abilities to foretell the future will always be limited. Because they can’t forecast the weather very far in advance and because the ice is strongly affected by winds, they have little confidence beyond what the long-term trend tells us in predictions that are made far in advance.

“The accuracy of our prediction really depends on time,” Zhang said. “Our June 1 prediction for the Sept. 15 low point has high uncertainty but as we approach the end of June or July, the uncertainty goes down and the accuracy goes up.”

In hindsight, that’s true historically for the average predictions collected by ‘s Sea Ice Outlook, a project funded by the National Science Foundation and the National Oceanic and Atmospheric Administration.

While the competitive aspect of the predictions is fun, the researchers aren’t in it to win it.

“Essentially it’s not for prediction but for understanding,” Zhang said. “We do it to improve our understanding of sea ice processes, in terms of how dynamic processes affect the seasonal evolution of sea ice.”

That may not be entirely the same for the enthusiasts who contribute a prediction. One polls readers in the summer for their best estimate of the sea ice low point. It’s included among the predictions collected by the Sea Ice Outlook, with an asterisk noting it as a “public outlook.”

The National Science Foundation and NASA fund the UW research into the Arctic sea ice low point.

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For more information, contact Lindsay at lindsay@apl.washington.edu or 206-543-5409
Zhang at zhang@apl.washington.edu or 206-543-5569

, an oceanographer with UW鈥檚 , set out to find if any endangered passed through the Fram Strait, an inhospitable, ice-covered stretch of sea between Greenland and the northern islands of Norway. Only around 40 sightings of bowhead whales, which were hunted almost to extinction, have been reported there since the 1970s.

Stafford and colleagues put two hydrophones, or underwater microphones, on moorings attached to the seafloor in Fram Strait, leaving them there for as long as the batteries would last: nearly a year. Since the population of bowhead whales likely to pass through was thought to number in the tens, they didn鈥檛 anticipate much interesting data.

鈥淲e hoped to record a few little grunts and moans,鈥� Stafford said. 鈥淲e were not expecting to get five months of straight singing.鈥�

Not only did they record singing nearly every hour of the day and night, they picked up more than 60 unique songs. A paper detailing their discoveries appears Tuesday (July 31) as the in Endangered Species Research and is openly accessible online.

The variety of tunes was so surprising that the researchers compared the whales鈥� song catalog to that of birds. 鈥淲hether individual singers display one, multiple or even all call types, the size of the song repertoire for鈥� bowheads in 2008-2009 is remarkable and more closely approaches that of songbirds than other鈥� whales,鈥� they wrote in the report.

They have yet to learn why the whales sang so consistently last year.

Scientists believe that bowhead whale song comes from males during mating season. In most other kinds of whales, individuals either sing the same song their whole lives or all members of a population sing the season鈥檚 same popular tune. If bowheads are like the former, that would mean more than 60 males were in the Fram Strait. If the population is evenly split between males and females, there could have been more than 100 whales 鈥� far more than anyone thought comprised this population.

With further study, the scientists instead could discover that individual bowhead whales have a repertoire of songs that they sing during a season. That would be equally interesting because it would make the bowheads the only known whales to sing a variety of songs in the same season.

The findings also hint at the possibility of a rebound in bowhead whales.

鈥淚f this is a breeding ground, it would be spectacular,鈥� said Stafford. 鈥淔or such a critically endangered species, it鈥檚 really important to know that there鈥檚 a reproductively active portion of the population.鈥�

In addition, since the whales are difficult to study given their year-round residence in the Arctic, virtually nothing was known about where they spend their winters. The research offers a clue about the whales鈥� migration path.

Only a handful of bowhead whale populations remain. The largest historic population, which includes the individuals studied for this report, once possibly numbered more than 30,000 members but was hunted to near-extinction from the 1600s through the 1800s. Commercial whaling reduced bowhead whale populations in other regions as well; combined, the four remaining populations are thought to number fewer than 10,000 members.

Bowhead whales are massive creatures. They grow to over 60 feet long, may live to 200 years old and can weigh 200,000 pounds. They use their huge skulls to break through ice as thick as 1.5 feet.

Bowhead whale song is unique in that the whales appear to sing with 鈥渢wo voices,鈥� simultaneously producing high- and low-frequency sounds. The whales sometimes repeat the same tune for hours at a time.

Stafford and her colleagues deployed the two hydrophones 60 miles apart. They made 2,144 hours of simultaneous recordings from September 2008 through July 2009. In order to conserve battery power and take recordings for a longer period of time, the hydrophones worked for nine minutes out of every half hour.

The hydrophone in the west, covered in dense ice and in colder water, picked up far more singing than the one in the east, where there was spotty ice coverage and warmer water. The greatest frequency of song occurred in the darkest, coldest period.

鈥淚t鈥檚 clear there鈥檚 a habitat preference,鈥� Stafford said. The thick canopy of ice may provide better acoustics than the loose pack ice and therefore might be favored by singing whales, she said.

鈥淎s Arctic sea ice declines, there may be some places like this that are important to protect in order to preserve a breeding ground for the bowhead whales,鈥� Stafford said.

To answer new questions that the data opens up 鈥� including how many whales make up this North Atlantic population 鈥� Stafford hopes to do additional study.

Co-authors of the paper include Sue Moore and Catherine Berchok from the National Oceanic and Atmospheric Administration; 脴ystein Wiig of the University of Oslo; Christian Lydersen, Edmond Hansen and Kit M. Kovacs from the Norwegian Polar Institute; and Dirk Kalmbach with the Alfred Wegener Institute of Polar and Marine Research in Germany. The research was funded by NOAA and supported by the Norwegian Polar Institute and the Alfred Wegener Institute.

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For more information, contact Stafford at 206-685-8617 or stafford@apl.washington.edu

Registered attendees can attend Baumans presentation of the paper at 11:20 a.m. on Friday, July 13, in room 118 of the William H. Gates School of Law.

“Cows are happy in parts of Northern California and not in Florida鈥� is a good way to sum up the findings of new research from the 天美影视传媒, said Yoram Bauman, best known as the “.鈥�

Bauman and colleagues found that the decline in milk production due to climate change will vary across the U.S., since there are significant differences in humidity and how much the temperature swings between night and day across the country. For instance, the humidity and hot nights make the Southeast the most unfriendly place in the country for dairy cows.

Their study combined high-resolution climate data and county-level dairy industry data with a method for figuring out how weather affects milk production. The result is a more detailed report than previous studies and includes a county-by-county assessment — that will be available to farmers — of the impact climate change will have on Holstein milk production in the U.S. through 2080.

Bauman, who contributed to the research while teaching for the UWs and is now a fellow at the , will present the findings during this weeks , held on the UW campus.

Scientists and the dairy industry have long known about and studied the impact of heat stress on cows’ milk production.

“Using U.S. Department of Agriculture statistics, if you look at milk production in the Southeast versus the Northwest, its very different,鈥� said , a postdoctoral researcher in the UWs and co-author of the paper. “Its reasonable to assume that some of that is due to the inhospitable environment for cows in the Southeast.鈥�

Previous research into how climate affects cow milk production in the U.S. was either limited in geographic scope or was too simplistic, ignoring the impact of humidity, for instance.

But by using detailed climate data covering night and day across the entire country, the researchers made some interesting discoveries. For instance, in Tillamook, Ore., where the climate is humid and the nighttime temperature doesnt change much, milk production begins to drop at a much lower temperature than in the dry Arizona climate. Tillamook cows become less productive starting at around 15 C, or 59 F, while those in Maricopa, Ariz., 聽start making less milk at around 25 C, or 77 F. In humid Okeechobee, Fla., cows become less productive at about the same temperature but losses increase at a much faster rate than in Arizona.

Fortunately for cows in Tillamook, however, the temperature there doesnt stray upward often and so actual milk losses are negligible, the researchers said. In Maricopa, the mean daily losses in summer, when the temperature soars, reach nearly 50 percent.

The authors also found that dairy farmers are already clustering in the most comfortable areas for cows, such as the cool coastal counties of Washington state.

But the outlook isnt good for areas across the southern U.S. where cows are already less productive in the heat of the summer.

“Perhaps most significantly, those regions that are currently experiencing the greatest losses are also the most susceptible: they are projected to be impacted the most by climate change,鈥� the researchers wrote in the paper.

Still, theres a notable silver lining in the report. While the researchers project that dairy production averaged across the U.S. will be about 6 percent lower in the 2080s than at the start of the century, other factors are likely to actually boost milk production even more.

“Management practices and breeding are on track to double milk production in Holsteins in the next 30 or 50 years,鈥� Mauger said. “So while a 6 percent drop is not negligible, its small compared to other positive influences.鈥�

The research could be valuable to farmers looking to evaluate the cost and effectiveness of methods for keeping cows cool. “You can pick up dairy cows and truck them elsewhere,鈥� said Bauman, who noted that ranchers looking to expand could make decisions based on climate.

The researchers plan to make the data freely available so that farmers can look up their counties and find how the climate may affect their cows.

Other co-authors are , an assistant professor at UW Bothell and member of the UWs Climate Impacts Group, and Tamilee Nennich of Purdue University.

The researchers hope next to look at the impact climate has on other barnyard animals, such as pigs, and other effects, such as mortality rate, that rising temperature might have on cows.

The Conference on Climate Change is put on by publisher Common Ground and will take place in the UWs William H. Gates building on Thursday and Friday.

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For more information, contact Yoram Bauman, 206-351-5719, yoram@uw.edu or Guillaume Mauger, 206-724-7284 (cell), gmauger@uw.edu.

Along the way it will collect important data about ocean properties including currents, microorganisms and temperature, sending the information in real time to scientists sitting comfortably in their offices–and with updates it will do this for 25 years.

As with the entire cabled observatory network, there is much about the equipment that is unprecedented. Other instruments used to collect data about oceans survive only a few years. Some only send data periodically or when scientists can retrieve them from the ocean.

“This is a really special thing,鈥� said , an engineer at the Applied Physics Lab who helped design the profiling system.

It is comprised of a floating platform about 650 feet below the surface and tethered to the ocean floor, nearly two miles under water. Attached to the platform is the profiler equipment which will float to the surface and get pulled back down by a winch.

Via the Internet, scientists will be able to remotely program the profiler to travel on different schedules. For instance, researchers may want the profiler to “stop and loiter,鈥� collecting data from as many as 15 sensors over a period of time at a certain depth, Cram said.

Even the cable that connects it to the winch is special. Inside it are wires that carry power from the main seafloor cable to the shallow profiler and that connect it to the Internet, Cram said. When one of the instruments on the shallow profiler picks up data, it transmits it over the Internet in real time so that scientists–or anyone with an Internet connection–can access it from land.

Much of the equipment will last for decades underwater because it is fabricated from titanium, the ultrastrong, lightweight metal that is also highly resistant to corrosion. But not every component will last that long. Some, like sensors, will wear out over time and be replaced.

Having the cabled observatory permanently in place and constantly collecting data is incredibly important for science, said , a UW alum and oceanographer with the University of South Florida who is helping develop the Ocean Observatories Initiative project.

“This is ground breaking,鈥� she said

Many events in the ocean, like storms, are episodic and scientists either cant get to the area to deploy instruments or they aren’t able to predict the specific event.

Other ocean processes change slowly over long periods of time and scientists need continuous measurements to study them.

“We know the ocean is changing, but we need high-frequency, continuous measurements over long periods of time to really understand it,鈥� Daly said.

The instruments on the shallow profiler will measure things like temperature, salinity, currents, oxygen, carbon dioxide and pH (ocean acidity).

Oceanographers from UW and other institutions collaborated closely with the engineers to design the profiler. During the planning phase, oceanographers determined the science requirements for the system. Now during the construction phase, the engineers are working closely with scientists to implement the envisioned system.

Cram and his team are now resolving final questions identified during the recent review and are just starting to build the system. They hope to begin testing their profiler in about six months. Deployment on the cabled network is scheduled for 2014.

The investment by the NSF in the Ocean Observatories Initiative, including construction and 25 years of operations, could reach $769.5 million. The UW is expected to receive nearly $235 million for design and construction of the underwater network and for initial instrumentation and operations.

Led by Professor John R. Delaney in the UW School of Oceanography, the observatory now being constructed comprises 560 miles of underwater fiber-optic cable as well as scientific instrumentation like the shallow water profiler. The observatory’s cabled network connects to shore in Pacific City, Oregon.

Other Ocean Observatories Initiative sites around the world will also collect ocean data at critical locations. The overall goal of the initiative is to build an infrastructure that will transform the studies of issues including climate variability, ocean circulation, air-sea exchange and geodynamics over entire tectonic plates.

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For more information, contact Nancy Penrose; UW OOI Communications Coordinator; 206-221-5781