Top weather conditions that amplify Lake Erie algal blooms revealed

Of the many weather-related factors that contribute to harmful algal blooms (HABs) in Lake Erie, a new study has identified one as most important: the wind.

Over a 10-year period in Lake Erie, wind speed contributed more consistently to HABs than sunshine or even precipitation, researchers at The Ohio State University and their colleagues found.

The ongoing study is unusual, in that researchers are building the first detailed analyses of how the various environmental factors influence each other -- in the context of satellite studies of Lake Erie.

They gave their early results at the American Geophysical Union meeting on Dec. 17.

To C.K. Shum, Distinguished University Scholar and professor of geodetic science at Ohio State, the finding "underscores the need for environmental agencies to incorporate the threat of extreme weather events caused by climate change into future algae mitigation strategies."

Where other studies have linked weather phenomena to HABs, this study goes a step further to look at how environmental drivers impact each other, and "ranks" them by their relative importance in promoting HABs, said Song Liang, formerly of Ohio State and now an associate professor of environmental and global health at the University of Florida.

"What surprised us the most was how the impact of nonweather factors, such as nitrogen and phosphorus pollution, varied strongly by season, while weather factors remained consistently important throughout the year," he said.

Researchers have long known that high nitrogen and phosphorus levels are the actual causes of HABs, which choke freshwater ecosystems and render the water toxic. But when it comes to the various environmental factors that can amplify the amount of these nutrients in the water, or aid or hamper the spread of algae, the relationships are much more complex.

"One of the objectives of this project is investigating historical patterns of harmful algal blooms and their linkage to water quality and environmental factors," explained project leader Jiyoung Lee, associate professor of environmental health sciences at Ohio State. "By doing this, we can better understand and predict the future of HABs and water safety in the Lake Erie community with the impact of changing climate and environmental factors."

Liang and his group analyzed nine environmental factors, including solar radiation, wind speed, precipitation, nitrogen concentration, water temperature and water quality in Lake Erie from 2002 to 2012. Then the larger research team used data from the sensor onboard the European Space Agency's Envisat satellite MEdium Resolution Imaging Spectrometer (MERIS) to examine how the color of the lake water changed during those years -- an indication of the concentration of the toxic blue-green algae present in HABs.

The researchers examined the environmental drivers by season, and found that wind speed affected the spread of algal blooms consistently throughout spring, summer and fall. Seasons of low winds led to larger blooms. That's because when wind speed is low, lake water is more still, and algae can more easily float to the top and form thick mats that spread along the lake surface.

Sunlight, meanwhile, was important in the spring and summer as a source of energy for the algae. Precipitation was very important in the summer and the winter, when rains and melting snow boosted runoff and delivered nitrogen and phosphorus, which algae use as food sources, to the lake.

As the project continues, the researchers hope to get a better understanding of how the variables relate to each other, and explore the notion of weather and climate as factors in a kind of "early warning system" for HABs.

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Even in restored forests, extreme weather strongly influences wildfire's impacts

The 2013 Rim Fire, the largest wildland fire ever recorded in the Sierra Nevada region, is still fresh in the minds of Californians, as is the urgent need to bring forests back to a more resilient condition. Land managers are using fire as a tool to mimic past fire conditions, restore fire-dependent forests, and reduce fuels in an effort to lessen the potential for large, high-intensity fires, like the Rim Fire. A study led by the U.S. Forest Service's Pacific Southwest Research Station (PSW) and recently published in the journal Forest Ecology and Management examined how the Rim Fire burned through forests with restored fire regimes in Yosemite National Park to determine whether they were as resistant to high-severity fire as many scientists and land managers expected.

Since the late 1960s, land managers in Yosemite National Park have used prescribed fire and let lower intensity wildland fires burn in an attempt to bring back historical fire regimes after decades of fire suppression. For this study, researchers seized a unique opportunity to study data on forest structure and fuels collected in 2009 and 2010 in Yosemite's old-growth, mixed-conifer forests that had previously burned at low to moderate severity. Using post-Rim Fire data and imagery, researchers found that areas burned on days the Rim Fire was dominated by a large pyro-convective plume -- a powerful column of smoke, gases, ash, and other debris -- burned at moderate to high severity regardless of the number of prior fires, topography, or forest conditions.

"The specific conditions leading to large plume formation are unknown, but what is clear from many observations is that these plumes are associated with extreme burning conditions," says Jamie Lydersen, PSW biological science technician and the study's lead author. "Plumes often form when atmospheric conditions are unstable, and result in erratic fire behavior driven by its own local effect on surface wind and temperatures that override the influence of more generalized climate factors measured at nearby weather stations."

When the extreme conditions caused by these plumes subsided during the Rim Fire, other factors influenced burn severity. "There was a strong influence of elapsed time since the last burn, where forests that experienced fire within the last 14 years burned mainly at low severity in the Rim Fire. Lower elevation areas and those with greater shrub cover tended to burn at higher severity," says Lydersen.

When driven by extreme weather, which often coincides with wildfires that escape initial containment efforts, fires can severely burn large swaths of forest regardless of ownership and fire history. These fires may only be controlled if more forests across the landscape have been managed for fuel reduction to allow early stage suppression before weather- and fuels-driven fire intensity makes containment impossible. Coordination of fire management activities by land management agencies across jurisdictions could favor burning under more moderate weather conditions when wildfires start and reduce the occurrences of harmful, high-intensity fires.

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In the mood to trade? Weather may influence institutional investors' stock decisions

Weather changes may affect how institutional investors decide on stock plays, according to a new study by a team of finance researchers. Their findings suggest sunny skies put professional investors more in a mood to buy, while cloudy conditions tend to discourage stock purchases.

The researchers conclude that cloudier days increase the perception that individual stocks and the Dow Jones Industrials are overpriced, increasing the inclination for institutions to sell.

The research paper, "Weather-Induced Mood, Institutional Investors, and Stock Returns," has been published in the January 2015 issue of The Review of Financial Studies. The research was collaborated by Case Western Reserve University's Dasol Kim and three other finance professors (William Goetzmann of Yale University, Alok Kumar of University of Miami and Qin Wang of University of Michigan-Dearborn).

Institutional investors represent large organizations, such as banks, mutual funds, labor union funds and finance or insurance companies that make substantial investments in stocks. Kim said the results of the study are surprising, given that professional investors are well regarded for their financial sophistication.

"We focus on institutional investors because of the important role they have in how stock prices are formed in the markets," said Kim, assistant professor of banking and finance at Case Western Reserve's Weatherhead School of Management. "Other studies have already shown that ordinary retail investors are susceptible to psychological biases in their investment decisions. Trying to evaluate similar questions for institutional investors is challenging, because relevant data is hard to come by."

Building on previous findings from psychological studies about the effect of sunshine on mood, the researchers wanted to learn how mood affects professional investor opinions on their stock market investments.

By linking responses to a survey of investors from the Yale Investor Behavior Project of Nobel Prize-winning economist Robert Shiller and institutional stock trade data with historical weather data from the National Oceanic and Atmospheric Administration, the researchers concluded aggregated data shows that seasonably sunnier weather leads to optimistic responses and a willingness to buy.

The research accounts for differences in weather across regions of the country and seasons. They show that these documented mood effects also influence stock prices, and that the observed impact does not persist for long periods of time.

A summary of the research was also recently featured at The Harvard Law School Forum on Corporate Governance and Financial Regulation.

Journal Reference:

W. N. Goetzmann, D. Kim, A. Kumar, Q. Wang. Weather-Induced Mood, Institutional Investors, and Stock Returns. Review of Financial Studies, 2014; 28 (1): 73 DOI: 10.1093/rfs/hhu063

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Global warming's influence on extreme weather

Understanding the cause-and-effect relationship between global warming and record-breaking weather requires asking precisely the right questions.

Extreme climate and weather events such as record high temperatures, intense downpours and severe storm surges are becoming more common in many parts of the world. But because high-quality weather records go back only about 100 years, most scientists have been reluctant to say if global warming affected particular extreme events.

On Wednesday, Dec. 17, at the American Geophysical Union's Fall Meeting in San Francisco, Noah Diffenbaugh, an associate professor of environmental Earth system science at the Stanford School of Earth Sciences, will discuss approaches to this challenge in a talk titled "Quantifying the Influence of Observed Global Warming on the Probability of Unprecedented Extreme Climate Events." He will focus on weather events that -- at the time they occur -- are more extreme than any other event in the historical record.

Diffenbaugh emphasizes that asking precisely the right question is critical for finding the correct answer.

"The media are often focused on whether global warming caused a particular event," said Diffenbaugh, who is a senior fellow at the Stanford Woods Institute for the Environment. "The more useful question for real-world decisions is: 'Is the probability of a particular event statistically different now compared with a climate without human influence?'"

Diffenbaugh said the research requires three elements: a long record of climate observations; a large collection of climate model experiments that accurately simulate the observed variations in climate; and advanced statistical techniques to analyze both the observations and the climate models.

One research challenge involves having just a few decades or a century of high-quality weather data with which to make sense of events that might occur once every 1,000 or 10,000 years in a theoretical climate without human influence.

But decision makers need to appreciate the influence of global warming on extreme climate and weather events.

"If we look over the last decade in the United States, there have been more than 70 events that have each caused at least $1 billion in damage, and a number of those have been considerably more costly," said Diffenbaugh. "Understanding whether the probability of those high-impact events has changed can help us to plan for future extreme events, and to value the costs and benefits of avoiding future global warming."

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Air pollution over Asia influences global weather and makes Pacific storms more intense

In the first study of its kind, scientists have compared air pollution rates from 1850 to 2000 and found that anthropogenic (human-made) particles from Asia impact the Pacific storm track that can influence weather over much of the world.

The team, which includes several researchers from Texas A&M University, has had its work published in the current issue of Proceedings of the National Academy of Sciences (PNAS).

Yuan Wang, Yun Lin, Jiaxi Hu, Bowen Pan, Misti Levy and Renyi Zhang of Texas A&M's Department of Atmospheric Sciences, along with colleagues from Pacific Northwest National Laboratory, the University of California at San Diego and NASA's Jet Propulsion Laboratory, contributed to the work.

The team used detailed pollution emission data compiled by the Intergovernmental Panel on Climate Change and looked at two scenarios: one for a rate in 1850 -- the pre-Industrial era -- and from 2000, termed present-day.

By comparing the results from an advanced global climate model, the team found that anthropogenic aerosols conclusively impact cloud formations and mid-latitude cyclones associated with the Pacific storm track.

"There appears to be little doubt that these particles from Asia affect storms sweeping across the Pacific and subsequently the weather patterns in North America and the rest of the world," Zhang says of the findings.

"The climate model is quite clear on this point. The aerosols formed by human activities from fast-growing Asian economies do impact storm formation and global air circulation downstream. They tend to make storms deeper and stronger and more intense, and these storms also have more precipitation in them. We believe this is the first time that a study has provided such a global perspective."

In recent years, researchers have learned that atmospheric aerosols affect the climate, either directly by scattering or absorbing solar radiation, and indirectly by altering cloud formations. Increasing levels of such particles have raised concerns because of their potential impacts on regional and global atmospheric circulation.

In addition, Zhang says large amounts of aerosols and their long-term transport from Asia across the Pacific can clearly be seen by satellite images.

The Pacific storm track represents a critical driver in the general global circulation by transporting heat and moisture, the team notes. The transfer of heat and moisture appears to be increased over the storm track downstream, meaning that the Pacific storm track is intensified because of the Asian air pollution outflow.

"Our results support previous findings that show that particles in the air over Asia tend to affect global weather patterns," Zhang adds.

"It shows they can affect the Earth's weather significantly."

Yuan Wang, who conducted the research with Zhang while at Texas A&M, currently works at NASA's Jet Propulsion Laboratory as a Caltech Postdoctoral Scholar.

The study was funded by grants from NASA, the Department of Energy, Texas A&M's Supercomputing facilities and the Ministry of Science and Technology of China.

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The ten best weather places in the world

Do you dream of a place that is always sunny? Where the temperature is perfect? Where there is virtually no severe weather? Ed Darack has. His article, "The 10 Best Weather Places in the World," featured in the March/April issue of Weatherwise magazine attempts to name the top ten places in the world that continually experience the best weather.

Darack defines what "best" weather consists of. The basis of this list is founded in weather that has positive effects on human fundamental needs (physical, mental, and emotional). "We can determine meteorological "best" criteria for ideal human physical, mental, and emotional health that includes temperature, humidity, average number of sunny days, and other criteria, by studying the results of research conducted on environmental effects on humans." With this in mind Darack creates a mythical place of weather perfection, 'Anthro-Weathertopia'. Here the temperature never strays too far from 68?F, the humidity is always comfortably 50%, and the clouds are never a threat. Unfortunately this perfect place does not exist, but his article lists the top ten places that come close.

The Manjimup region of the extreme south west region of Western Australia ranks at number ten on the list. It is a piece of lush land off the southern Indian Ocean. In February, the average summer temperature clocks in at 81?F during the day and 56.1?F at night. In the winter, the coldest month, July, records an average temperature high of 58?F and low of 43.5?F. There is an average rainfall of 39 inches per year. The only drawback is that, although rarely, the Manjimup region does experience extended periods of cold and rain.

Number six on the list is one of the most comfortable weather cities on the planet, Lisbon, Portugal. Lisbon, located on the Atlantic coast of Portugal, experiences moderate temperature throughout the year. In August, the warmest month, the daily average temperature is 82.9?F with a mean nighttime low of 65.5?F. January, the coldest month, Lisbon experiences a daily high on 58.6?F and a nighttime low of 46.9?F. The yearly average rainfall is 30.5 inches.

Next we visit the northwestern coast of Morocco, which stands at number three. The cold currents of the Atlantic Ocean provide little season variability and extremely mild temperatures year round. The heart of this region is Casablanca which records an average daily high of 63?F and a mean evening low of 45?F. The average rainfall in December, the wettest month, only comes to 5.75 inches and less than .5 inches in July, the driest. In addition, the northwestern coast almost never experiences any type of severe weather.

Can't imagine anywhere else having such perfect weather? Find out which other places made the list by accessing "The 10 Best Weather Places in the World."

Story Source:

The above story is based on materials provided by Taylor & Francis. Note: Materials may be edited for content and length.

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New NASA Van Allen Probes observations helping to improve space weather models

Using data from NASA's Van Allen Probes, researchers have tested and improved a model to help forecast what's happening in the radiation environment of near-Earth space -- a place seething with fast-moving particles and a space weather system that varies in response to incoming energy and particles from the sun.

NASA's Van Allen Probes orbit through two giant radiation belts that surround Earth. Their observations help improve computer simulations of events in the belts that can affect technology in space.

When events in the two giant doughnuts of radiation around Earth -- called the Van Allen radiation belts -- cause the belts to swell and electrons to accelerate to 99 percent the speed of light, nearby satellites can feel the effects. Scientists ultimately want to be able to predict these changes, which requires understanding of what causes them.

Now, two sets of related research published in the Geophysical Research Letters improve on these goals. By combining new data from the Van Allen Probes with a high-powered computer model, the new research provides a robust way to simulate events in the Van Allen belts.

"The Van Allen Probes are gathering great measurements, but they can't tell you what is happening everywhere at the same time," said Geoff Reeves, a space scientist at Los Alamos National Laboratory, or LANL, in Los Alamos, N.M., a co-author on both of the recent papers. "We need models to provide a context, to describe the whole system, based on the Van Allen Probe observations."

Prior to the launch of the Van Allen Probes in August 2012, there were no operating spacecraft designed to collect real-time information in the radiation belts. Understanding of what might be happening in any locale was forced to rely mainly on interpreting historical data, particularly those from the early 1990s gathered by the Combined Release and Radiation Effects Satellite, or CRRES.

Imagine if meteorologists wanted to predict the temperature on March 5, 2014, in Washington, D.C. but the only information available was from a handful of measurements made in March over the last seven years up and down the East Coast. That's not exactly enough information to decide whether or not you need to wear your hat and gloves on any given day in the nation's capital.

Thankfully, we have much more historical information, models that help us predict the weather and, of course, innumerable thermometers in any given city to measure temperature in real time. The Van Allen Probes are one step toward gathering more information about space weather in the radiation belts, but they do not have the ability to observe events everywhere at once. So scientists use the data they now have available to build computer simulations that fill in the gaps.

The recent work centers around using Van Allen Probes data to improve a three-dimensional model created by scientists at LANL, called DREAM3D, which stands for Dynamic Radiation Environment Assimilation Model in 3 Dimensions. Until now the model relied heavily on the averaged data from the CRRES mission.

One of the recent papers, published Feb. 7, 2014, provides a technique for gathering real-time global measurements of chorus waves, which are crucial in providing energy to electrons in the radiation belts. The team compared Van Allen Probes data of chorus wave behavior in the belts to data from the National Oceanic and Atmospheric Administration's Polar-orbiting Operational Environmental Satellites, or POES, flying below the belts at low altitude. Using this data and some other historical examples, they correlated the low-energy electrons falling out of the belts to what was happening directly in the belts.

"Once we established the relationship between the chorus waves and the precipitating electrons, we can use the POES satellite constellation -- which has quite a few satellites orbiting Earth and get really good coverage of the electrons coming out of the belts," said Los Alamos scientist Yue Chen, first author of the chorus waves paper. "Combining that data with a few wave measurements from a single satellite, we can remotely sense what's happening with the chorus waves throughout the whole belt."

The relationship between the precipitating electrons and the chorus waves does not have a one-to-one precision, but it does provide a much narrower range of possibilities for what's happening in the belts. In the metaphor of trying to find the temperature for Washington on March 5, it's as if you still didn't have a thermometer in the city itself, but can make a better estimate of the temperature because you have measurements of the dewpoint and humidity in a nearby suburb.

The second paper describes a process of augmenting the DREAM3D model with data from the chorus wave technique, from the Van Allen Probes, and from NASA's Advanced Composition Explorer, or ACE, which measures particles from the solar wind. Los Alamos researchers compared simulations from their model -- which now was able to incorporate real-time information for the first time -- to a solar storm from October 2012.

"This was a remarkable and dynamic storm," said lead author Weichao Tu at Los Alamos. "Activity peaked twice over the course of the storm. The first time the fast electrons were completely wiped out -- it was a fast drop out. The second time many electrons were accelerated substantially. There were a thousand times more high-energy electrons within a few hours."

Tu and her team ran the DREAM3D model using the chorus wave information and by including observations from the Van Allen Probes and ACE. The scientists found that their computer simulation made by their model recreated an event very similar to the October 2012 storm.

What's more the model helped explain the different effects of the different peaks. During the first peak, there simply were fewer electrons around to be accelerated.

However, during the early parts of the storm the solar wind funneled electrons into the belts. So, during the second peak, there were more electrons to accelerate.

"That gives us some confidence in our model," said Reeves. "And, more importantly, it gives us confidence that we are starting to understand what's going on in the radiation belts."

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Harsh weather conditions increase cost of food

Many of your favorite products at the grocery store are going to cost more, according to Glynn Tonsor, associate professor of agricultural economics at Kansas State University.

"When consumers walk in the grocery store, they are going to have to continue to juggle what they put in those baskets," Tonsor said.

Several items will cost more this year, including beef, pork, vegetables and nuts. Most of the increase in price is because of extreme drought facing several states.

"Most people recognize weather has a big hand in food production," Tonsor said. "What they might not recognize is the actual location of food production around the country and therefore how weather across the country impacts the food prices they see."

California, described as the salad bowl of the United States, produces more than 90 percent of select vegetables and nut products. However, the state is facing extreme drought conditions. That means fewer of these products are available. Tonsor says the limited supply will increase the price of the products anywhere from 5 to 20 percent.

Drought is also taking a toll on beef. The drought in Oklahoma, coupled with the already historically low amount of cattle in the United States, will hike up the price for beef.

"It's not just a weather story," Tonsor said. "The other thing that's getting talked a lot about that will show up at the meat counter is animal health issues, particularly in the pork industry.

These animal health issues do not affect human health, but they do decrease the amount of pork available. That could affect the prices at the grocery store by summer, Tonsor said.

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New airborne GPS technology for weather conditions takes flight

GPS technology has broadly advanced science and society's ability to pinpoint precise information, from driving directions to tracking ground motions during earthquakes. A new technique led by a researcher at Scripps Institution of Oceanography at UC San Diego stands to improve weather models and hurricane forecasting by detecting precise conditions in the atmosphere through a new GPS system aboard airplanes.

The first demonstration of the technique, detailed in the journal Geophysical Research Letters (GRL), is pushing the project's leaders toward a goal of broadly implementing the technology in the near future on commercial aircraft.

Current measurement systems that use GPS satellite signals as a source to probe the atmosphere rely on GPS receivers that are fixed to ground and can't measure over the ocean, or they rely on GPS receivers that are also on satellites that are expensive to launch and only occasionally measure in regions near storms. The new system, led by Scripps Institution of Oceanography geophysicist Jennifer Haase and her colleagues, captures detailed meteorological readings at different elevations at targeted areas of interest, such as over the Atlantic Ocean in regions where hurricanes might develop.

"This field campaign demonstrated the potential for creating an entirely new operational atmospheric observing system for precise moisture profiling from commercial aircraft," said Haase, an associate researcher with the Cecil H. and Ida M. Green Institute of Physics and Planetary Physics (IGPP) at Scripps. "Having dense, detailed information about the vertical moisture distribution close to the storms is an important advancement, so if you put this information into a weather model it will actually have an impact and improve the forecast."

"These are exciting results, especially given the complications involved in working from an airplane," says Eric DeWeaver, program director in the National Science Foundation's (NSF) Division of Atmospheric and Geospace Sciences, which funded the research. "Satellite-based measurements are now regularly used for weather forecasting and have a big impact, but airplanes can go beyond satellites in making observations that are targeted right where you want them."

The GRL paper details a 2010 flight campaign aboard NSF aircraft and subsequent data analysis that demonstrated for the first time that atmospheric information could be captured by an airborne GPS device. The instrumentation, which the scientists labeled "GISMOS" (GNSS [Global Navigation Satellite System] Instrument System for Multistatic and Occultation Sensing), increased the number of atmospheric profiles for studying the evolution of tropical storms by more than 50 percent.

"We're looking at how moisture evolves so when we see tropical waves moving across the Atlantic, we can learn more about which one is going to turn into a hurricane," said Haase. "So being able to look at what happens in these events at the early stages will give us a lot longer lead time for hurricane warnings."

"This is another case where the effective use of GPS has the potential to improve the forecast and therefore save lives," said Richard Anthes, president emeritus of the University Corporation for Atmospheric Research, which currently runs the satellite based GPS measurements system called COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate).

While the current GISMOS design occupies a refrigerator's worth of space, Haase and her colleagues are working to miniaturize the technology to shoe box size. From there, the system can more feasibly fit onto commercial aircraft, with hundreds of daily flights and a potential flood of new atmospheric data to greatly improve hurricane forecasting and weather models.

The technology also could improve interpretation of long-term climate models by advancing scientists' understanding of factors such as the moisture conditions that are favorable for hurricane development.

Paytsar Muradyan, who recently received a Ph.D. from Purdue University in atmospheric sciences, started working with Haase in 2007 as a graduate student during the formative stages of GISMOS's design and development. She eventually flew with the group in the 2010 campaign and took away a wealth of experience from the demands of the project.

"It was a lot of responsibility but certainly rewarding to work with a group of world-known scientists in an interdisciplinary project," said Muradyan.

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Ancient stormy weather: World's oldest weather report could revise bronze age chronology

An inscription on a 3,500-year-old stone block from Egypt may be one of the world's oldest weather reports -- and could provide new evidence about the chronology of events in the ancient Middle East.

A new translation of a 40-line inscription on the 6-foot-tall calcite block called the Tempest Stela describes rain, darkness and "the sky being in storm without cessation, louder than the cries of the masses."

Two scholars at the University of Chicago's Oriental Institute believe the unusual weather patterns described on the slab were the result of a massive volcano explosion at Thera -- the present-day island of Santorini in the Mediterranean Sea. Because volcano eruptions can have a widespread impact on weather, the Thera explosion likely would have caused significant disruptions in Egypt.

The new translation suggests the Egyptian pharaoh Ahmose ruled at a time closer to the Thera eruption than previously thought -- a finding that could change scholars' understanding of a critical juncture in human history as Bronze Age empires realigned. The research from the Oriental Institute's Nadine Moeller and Robert Ritner appears in the spring issue of the Journal of Near Eastern Studies.

The Tempest Stela dates back to the reign of the pharaoh Ahmose, the first pharaoh of the 18th Dynasty. His rule marked the beginning of the New Kingdom, a time when Egypt's power reached its height. The block was found in pieces in Thebes, modern Luxor, where Ahmose ruled.

If the stela does describe the aftermath of the Thera catastrophe, the correct dating of the stela itself and Ahmose's reign, currently thought to be about 1550 B.C., could actually be 30 to 50 years earlier.

"This is important to scholars of the ancient Near East and eastern Mediterranean, generally because the chronology that archaeologists use is based on the lists of Egyptian pharaohs, and this new information could adjust those dates," said Moeller, assistant professor of Egyptian archaeology at the Oriental Institute, who specializes in research on ancient urbanism and chronology.

In 2006, radiocarbon testing of an olive tree buried under volcanic residue placed the date of the Thera eruption at 1621-1605 B.C. Until now, the archeological evidence for the date of the Thera eruption seemed at odds with the radiocarbon dating, explained Oriental Institute postdoctoral scholar Felix Hoeflmayer, who has studied the chronological implications related to the eruption. However, if the date of Ahmose's reign is earlier than previously believed, the resulting shift in chronology "might solve the whole problem," Hoeflmayer said.

The revised dating of Ahmose's reign could mean the dates of other events in the ancient Near East fit together more logically, scholars said. For example, it realigns the dates of important events such as the fall of the power of the Canaanites and the collapse of the Babylonian Empire, said David Schloen, associate professor in the Oriental Institute and Near Eastern Languages & Civilizations on ancient cultures in the Middle East.

"This new information would provide a better understanding of the role of the environment in the development and destruction of empires in the ancient Middle East," he said. For example, the new chronology helps to explain how Ahmose rose to power and supplanted the Canaanite rulers of Egypt -- the Hyksos -- according to Schloen. The Thera eruption and resulting tsunami would have destroyed the Hyksos' ports and significantly weakened their sea power.

In addition, the disruption to trade and agriculture caused by the eruption would have undermined the power of the Babylonian Empire and could explain why the Babylonians were unable to fend off an invasion of the Hittites, another ancient culture that flourished in what is now Turkey.

A tempest of rain

Some researchers consider the text on the Tempest Stela to be a metaphorical document that described the impact of the Hyksos invasion. However, Ritner's translation shows that the text was more likely a description of weather events consistent with the disruption caused by the massive Thera explosion.

Ritner said the text reports that Ahmose witnessed the disaster -- the description of events in the stela text is frightening.

The stela's text describes the "sky being in storm" with "a tempest of rain" for a period of days. The passages also describe bodies floating down the Nile like "skiffs of papyrus." Importantly, the text refers to events affecting both the delta region and the area of Egypt further south along the Nile. "This was clearly a major storm, and different from the kinds of heavy rains that Egypt periodically receives," Ritner said.

In addition to the Tempest Stela, a text known as the Rhind Mathematical Papyrus from the reign of Ahmose also makes a special point of mentioning thunder and rain, "which is further proof that the scholars under Ahmose paid close and particular attention to matters of weather," Ritner said.

Marina Baldi, a scientist in climatology and meteorology at the Institute of Biometeorology of the National Research Council in Italy, has analyzed the information on the stela along with her colleagues and compared it to known weather patterns in Egypt.

A dominant weather pattern in the area is a system called "the Red Sea Trough," which brings hot, dry air to the area from East Africa. When disrupted, that system can bring severe weather, heavy precipitation and flash flooding, similar to what is reported on the Tempest Stela.

"A modification in the atmospheric circulation after the eruption could have driven a change in the precipitation regime of the region. Therefore the episode in the Tempest Stela could be a consequence of these climatological changes," Baldi explained.

Other work is underway to get a clearer idea of accurate dating around the time of Ahmose, who ruled after the Second Intermediate period when the Hyksos people seized power in Egypt. That work also has pushed back the dates of his reign closer to the explosion on Thera, Moeller explained.

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Air pollution from Asia affecting world's weather

Extreme air pollution in Asia is affecting the world's weather and climate patterns, according to a study by Texas A&M University and NASA's Jet Propulsion Laboratory researchers.

Yuan Wang, a former doctoral student at Texas A&M, along with Texas A&M atmospheric sciences professors Renyi Zhang and R. Saravanan, have had their findings published in the current issue of Nature Communications.

Using climate models and data collected about aerosols and meteorology over the past 30 years, the researchers found that air pollution over Asia -- much of it coming from China -- is impacting global air circulations.

"The models clearly show that pollution originating from Asia has an impact on the upper atmosphere and it appears to make such storms or cyclones even stronger," Zhang explains.

"This pollution affects cloud formations, precipitation, storm intensity and other factors and eventually impacts climate. Most likely, pollution from Asia can have important consequences on the weather pattern here over North America."

China's booming economy during the last 30 years has led to the building of enormous manufacturing factories, industrial plants, power plants and other facilities that produce huge amounts of air pollutants. Once emitted into the atmosphere, pollutant particles affect cloud formations and weather systems worldwide, the study shows.

Increases in coal burning and car emissions are major sources of pollution in China and other Asian countries.

Air pollution levels in some Chinese cities, such as Beijing, are often more than 100 times higher than acceptable limits set by the World Health Organization standards, Zhang says.

One study has shown that lung cancer rates have increased 400 percent in some areas due to the ever-growing pollution problem.

Conditions tend to worsen during winter months when a combination of stagnant weather patterns mixed with increased coal burning in many Asian cities can create pollution and smog that can last for weeks. The Chinese government has pledged to toughen pollution standards and to commit sufficient financial resources to attack the problem. "The models we have used and our data are very consistent with the results we have reached," Saravanan says.

"Huge amounts of aerosols from Asia go as high as six miles up in the atmosphere and these have an unmistakable impact on cloud formations and weather."

Zhang adds that "we need to do some future research on exactly how these aerosols are transported globally and impact climate. There are many other atmospheric observations and models we need to look at to see how this entire process works."

Yuan Wang, who conducted the research with Zhang while at Texas A&M, currently works at NASA's Jet Propulsion Laboratory as a Caltech Postdoctoral Scholar.

The study was funded by grants from NASA, Texas A&M's Supercomputing facilities and the Ministry of Science and Technology of China.

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Hot weather deaths projected to rise 257 percent in UK by 2050s, experts warn

The number of annual excess deaths caused by hot weather in England and Wales is projected to surge by 257% by the middle of the century, as a result of climate change and population growth, concludes research published online in the Journal of Epidemiology and Community Health.

The elderly (75+) will be most at risk, particularly in the South and the Midlands, the findings suggest.

The research team, from the London School of Hygiene and Tropical Medicine, and Public Health England, used time-series regression analysis to chart historic (1993-2006) fluctuations in weather patterns and death rates to characterise the associations between temperature and mortality, by region and by age group.

They then applied these to projected population increases and local climate to estimate the future number of deaths likely to be caused by temperature -- hot and cold -- for the 2020s, 2050s, and 2080s.

They based their calculations on the projected daily average temperatures for 2000-09, 2020-29, 2050-59 and 2080-89, derived from the British Atmospheric Data Centre (BADC), and population growth estimates from the Office of National Statistics.

The calculations indicated a significantly increased risk of deaths associated with temperature across all regions of the UK, with the elderly most at risk.

The number of hot weather days is projected to rise steeply, tripling in frequency by the mid 2080s, while the number of cold days is expected to fall, but at a less dramatic pace.

At the national level, the death rate increases by just over 2% for every 1?C rise in temperature above the heat threshold, with a corresponding 2% increase in the death rate for every 1?C fall in temperature below the cold threshold.

In the absence of any adaptive measures, excess deaths related to heat would be expected to rise by 257% by the 2050s, from an annual baseline of 2000, while those related to the cold would be expected to fall by 2% as a result of milder winters, from a current toll of around 41,000, but will still remain significant.

Those aged 85 and over will be most at risk, partly as a result of population growth -- projected to reach 89 million by the mid 2080s -- and the increasing proportion of elderly in the population, say the authors.

Regional variations are likely to persist: London and the Midlands are the regions most vulnerable to the impact of heat, while Wales, the North West, Eastern England and the South are most vulnerable to the impact of cold.

Rising fuel costs may make it harder to adapt to extremes of temperature, while increased reliance on active cooling systems could simply end up driving up energy consumption and worsening the impact of climate change, say the authors.

Better and more sustainable options might instead include shading, thermal insulation, choice of construction materials implemented at the design stage of urban developments, suggest the authors.

While the death toll from cold weather temperatures will remain higher than that caused by hot temperatures, the authors warn that health protection from hot weather will become increasingly necessary -- and vital for the very old.

"As the contribution of population growth and aging on future temperature related health burdens will be large, the health protection of the elderly will be important," warn the authors, recalling the social changes that have led to many elderly living on their own -- a contributory factor to the high death toll in France in the 2003 heatwave.

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'Standing on a comet': Rosetta mission will contribute to space weather research

A comet-bound spacecraft that's been in sleep mode for more than two years is scheduled to wake up on the morning of Jan. 20 -- beginning the home stretch of its decade-long journey to a mile-wide ball of rock, dust and ice.

If all goes as planned, Rosetta -- a European Space Agency-led mission that involves University of Michigan engineers and scientists -- will be the first craft to actually land on a comet as well as track it for an extended period of time.

The Philae lander will latch on to the core of comet 67P/Churyumov-Gerasimenko in November and the orbiter will operate until the end of 2015. No mission has ever attempted such an in-depth look at one of these relics of the earliest days of our solar system.

Engineers at U-M's Space Physics Research Lab built electronic components for an onboard instrument that's believed to be the most sensitive of its kind ever flown in space. And a team of researchers will be involved in the mission science as well.

While most of the big questions Rosetta aims to answer deal with the origin and evolution of the solar system, U-M scientists will make a unique contribution that could provide very practical insights into how the sun and planets interface today.

They'll analyze measurements taken at the comet to study solar wind interactions that can lead to solar storms. The solar wind is a stream of charged particles emanating from the sun. Solar storms are bursts of activity that can threaten astronauts and damage Earth's satellites and electric grid.

"How the solar wind operates is one of the biggest outstanding questions about the solar system today. By studying how it interacts with cometary gases, we can learn a lot about the composition of the solar wind," said Tamas Gombosi, the Rollin M. Gerstacker Professor of Engineering in the Department of Atmospheric, Oceanic and Space Sciences.

Gombosi and his research group are leaders in the field of space weather. A model they developed was recently adopted by the national Space Weather Prediction Center.

At the sun's equator, the wind travels rather slowly, Gombosi said. It moves faster at high latitudes. Interactions between the two varieties can lead to magnetospheric storms. Earth orbits near the equator, so it's hard to study the fast wind from our vantage point.

"But comets pass through all of it. With their help, we can study the fast solar wind," Gombosi said.

Gombosi and other U-M researchers will be involved in additional Rosetta goals. They'll study and simulate how quickly the comet outgases material from its nucleus to its tail as it rings around the sun. They'll be involved in examining what elements are in the comet's tail, atmosphere and ionosphere, as well as how fast the electrified particles in the ionosphere are traveling.

Michael Combi, the Freeman Devold Miller Collegiate Research Professor in the Department of Atmospheric, Oceanic and Space Sciences, is a co-investigator on several instruments. He'll look into the rate at which the comet's core is sublimating, or turning from a solid into a gas, and he'll also work on a team that's analyzing those gases. They'll explore the levels of carbon monoxide and carbon dioxide, for example. They can't detect carbon dioxide from Earth.

"It's very difficult to observe some of the chemical species when they're far away and faint. Carbon dioxide is probably the second most abundant species at most comets, but it's not been observed in the thousands we've looked at from Earth," said Combi, who has studied comets for more than 30 years.

Comets -- small rock and ice bodies -- were present in the nebula that spawned the solar system and have been orbiting ever since in far away, cold belts either just past the orbit of Neptune or a quarter of the distance to the nearest star. For scientists, they're archeological artifacts that help them understand how the solar system formed and evolved. They're believed to have delivered Earth's oceans and perhaps the seeds of life in organic materials.

"People use the analogy that it's been in the freezer for the past 4.5 million years and brought in for convenient study. So we're looking as much as we can at the way the way the solar system was 4.5 billion years ago," Combi said.

Comet 67P/Churyumov-Gerasimenko is one of the smallest bodies humans have ever tried to land on. Its gravity is about 1,000 times less than that of Earth.

"On the lander, there's a camera that can look straight down like you're standing up and looking at the ground. Then there's a panoramic camera that can look out and see a picture of the horizon. It'll be fun to see what this landscape looks like," Combi said. "It'll be like standing on a comet."

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A whole new meaning to bad weather: Top ten worst weather places in the world

Have you ever wondered what places on Earth experience the worst weather? Ed Darack has. His article, "The 10 Worst Weather Places in the World," featured in this month's issue of Weatherwise magazineattempts to name the top ten places in the world that continually experience the most extreme weather. Inverting our fascination with "the grass is always greener" lists, (best beaches, places to live, vacation, etc.), Darack investigates the top ten places in the world with the worst weather.

Darack defines "bad" weather, what a "place" consists of, and the analysis of the conditions themselves. However, due to the lack of comprehensive global meteorological research, especially in the harshest climates where the risk to human life is significant, Darack relies on the available data and an effort to be objective.

Oymyakon, Republic of Sakha, Russian Siberia ranks number ten on the list. It has been recorded, although with dispute, that Oymyakon has reached the lowest temperature of Earth outside of Antarctica and the coldest permanently inhabited place at -89.9?F. On average, it drops to -50?F every night. Also, it is one of the places on the planet with the greatest annual swing rising to 86?F during the summer.

Number six on the list is Gandom-e Beryan, Dasht-e Lut, Iran, which is known for the hottest land surface temperature ever recorded. Using data from NASA's Earth Observing System's Aqua satellite, measuring the skin temperature of the planet, Gandom-e Beryan reached a staggering 159.3?F over the course of 2003-2009.

Next we visit the entire coastline of Antarctica, which stands at number three, not so much for the temperature, although extremely freezing, as for the storms. The driest continent meeting the world's most tumultuous ocean, the Southern Ocean, results in almost constant storms racing around the continent. In addition, extreme katabatic wind is also a factor. At Cape Dension in Commonwealth Bay in 1995 a wind speed of 129mph was measured. The highest wind speed ever recorded in Antarctica was 199mph.

Find out which other places made the list by accessing "The 10 Worst Weather Places in the World" free until the end of December 2013: http://www.weatherwise.org/Archives/Back%20Issues/2013/November-December%202013/10_worst_full.html

Story Source:

The above story is based on materials provided by Taylor & Francis. Note: Materials may be edited for content and length.

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New phone alerts for extreme weather may prevent casualties in India

When Cyclone Phailin hit India in late 2013 it became the largest storm to batter the subcontinent in over a decade. The storm, officially classified as a Category 5 tropical cyclone, affected more than 12 million people in India and neighboring countries, and required mass evacuations.

These evacuations revealed an urgent need for an effective alert system which could forewarn the majority of the population. A new paper published in Atmospheric Science Letters details how computer science undergraduates have created image based mobile phone alerts, connected to the Weather Research and Forecasting system.

India has a mobile phone subscriber base exceeding 929 million people and this is expected to touch 1.15 billion by the end of 2014. An alert system developed for mobiles could reach an estimated 97% of the population..

The paper details how during the 2013 storm the computer scientists were able to track its genesis, progression and landfall. By converting this information into images suitable for phones, they created a forecasting and warning system accessible to ordinary citizens.

"Cyclone alerts can save lives and property, but must be easily accessible," said Dr. Sat Ghosh. "The global perception of India's emerging IT prowess is lopsided. It is thought of as merely a manufacturing hub; however, our article puts the country's numerical literacy to practical use. The easy-to-use Weather Research and Forecasting model remains confined to an elite group of users, such as atmospheric scientists and weather forecasters. Our research explores how the WRF forecast can be interfaced with mobile telephony which has a deep penetration even in rural pockets of India."

Story Source:

The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length.

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National Weather Service completes Doppler radar upgrades

April 25, 2013

Dual-pol data shows what type of precipitation is falling based on its shape.

Download here (Credit: NOAA)

This week, the National Weather Service completed the dual-polarization technology update in Brownsville, Texas – concluding the 122 NWS radar site upgrades throughout the country. This new advanced technology is helping federal weather forecasters more accurately track, assess and warn the public of approaching high-impact weather.

Dual-polarization is the most significant enhancement made to the nation’s federal weather radar system since Doppler technology was first installed in the early 1990s. Dual-pol radar sends and receives both horizontal and vertical pulses, which produces a much more informative picture of the size and shape of the objects in the sky. This provides meteorologists the ability to distinguish between rain, snow, hail and non-weather items like wildfire smoke plumes, birds and insects. Conventional Doppler radar only has a one-dimensional view making it difficult to tell the type of precipitation or object in the sky.

The radar receiving dish inside the protective cover. Dual-pol is both a hardware and software upgrade to the radar.

Download here (Credit: NOAA)

“This achievement is the result of years of research, development and continued investment that’s helping us become a more weather-ready nation,” said Dr. Louis Uccellini, director, NOAA’s National Weather Service. “It is amazing what we can see with dual-pol technology. This game-changing technology has already helped forecasters issue more accurate and timely warnings to the public and has saved lives.”

Dual-pol is credited with providing improved detection of heavy rainfall, which can increase warning time for flash floods. During winter storms, forecasters use dual-pol information to monitor a transition from snow to sleet and freezing rain, which allows for a more accurate forecast. Dual-pol can also spot airborne debris giving forecasters the ability to confirm a tornado on the ground, even in the dark or when hidden by heavy rain. The new technology has also been used to help detect hazards to aircraft, such as volcanic ash plumes, icing conditions and birds.

“I am committed to supporting the National Weather Service’s critical mission of forecasting and warning about severe weather, and supporting the men and women who work every day to fulfill that mission”, said Senator Barbara A. Mikulski, chairwoman of the Appropriations subcommittee that funds NOAA, “We owe it to our communities – to the coastal states that depend on accurate hurricane forecasts, and to the interior states that depend on timely tornado warnings – to make sure our weather offices are fit for duty. These new state-of-the-art radars will ensure our forecasters have the tools and technology they need to protect lives and livelihoods.”

Dual-polarization is the most significant enhancement made to the nation’s Next Generation Weather Radar network, NEXRAD, since Doppler radar was first installed in the early 1990s.

Download here (Credit: NOAA)

The National Weather Service has used dual-pol to develop 14 new radar products that have improved the speed, understanding, and accuracy of the information it provides about extreme weather. Forecasters now have more confidence to accurately assess weather events and be more descriptive in weather warnings, which helps improve public response to the warnings.

The nationwide dual-pol upgrade began in Sept. 2011 and the public has been benefiting from the new technology every day since. Here are a few successes:

On Feb. 10, 2013, NWS weather forecasters in Jackson, Miss., used the new radar technology to confirm a powerful tornado (EF-4) was moving across Southern Mississippi’s Lamar County toward the populated city of Hattiesburg. Forecasters warned the public using detailed, descriptive language about the tornado’s size and path, resulting in no fatalities. On the same day, dual-pol information helped the Jackson forecasters recognize thunderstorms with particularly heavy rainfall rates, enabling them to issue flash flood warnings more than an hour before flash flooding started.

Dual-pol technology can also identify non-weather targets such as bugs, bats or debris from a tornado producing damage on the ground.

Download here (Credit: NOAA)

On Nov. 7-8, 2012, NWS meteorologists at the Boston forecast office relied on dual-pol radar information to help locate the rain/snow line as a nor’easter traversed the area. During the afternoon and evening, a storm formed across Rhode Island and eastern Massachusetts. Snow fell to the west of the boundary where temperatures dipped into the 30s, while rain fell to the east where temperatures held in the 40s. Using dual-pol information, forecasters were able to accurately track the slow progress of the rain-snow line and provide short term forecasts which helped department of transportation officials focus their snow removal assets and for the media to highlight the hazardous routes to the traveling public. The NWS forecast office in Phoenix relied on dual-pol technology to successfully warn for a very large dust storm that moved across the metro area during the early evening of July 5, 2011. There were widespread reports of near-zero visibility and winds gusting more than 50 mph. Dual-pol radar data estimated this dust storm reached a peak height of at least 5,000 to 6,000 feet, with a leading edge stretching close to 100 miles and traveling at least 150 miles. Forecasters collaborated with emergency management and media partners, providing details on potential impacts as the dust approached from the southeast.  Dust storm warnings described the large size of the dust area and the potential for widespread low visibilities of less than a quarter mile.  Safety tips in the warnings and updating warning statements helped people in the storm's path make fast and smart decisions.

In addition to the 122 NWS-owned radars, the full nationwide radar network includes another 37 radar sites owned by the FAA and Defense Department, which will be completely upgraded to dual-pol technology this summer. NOAA’s NEXRAD radar program is a tri-agency effort with NOAA, the Federal Aviation Administration, and the United States Air Force.

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels.

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NOAA, EUMETSAT sign long-term agreement for weather, climate monitoring

August 28, 2013

Building on a 30-year relationship, top officials from NOAA and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) signed a long-term cooperative agreement, ensuring continued space-based weather, water and climate monitoring.

At a ceremony at the European Union (EU) Delegation in Washington, D.C. yesterday, Kathryn D. Sullivan, Ph.D., NOAA acting administrator and Alain Ratier, EUMETSAT’s director general, signed the agreement. They were joined by Dr. Francois Rivasseau, deputy chief of mission, EU Delegation to the United States.

“The need for environmental intelligence has never been stronger. This partnership with our EUMETSAT colleagues allows us to continue collecting and sharing vital space-based observations, resulting in a better understanding of our global environment,” Sullivan said.

Ratier added, “The partnership between EUMETSAT and NOAA has continuously developed over the last 30 years and taken a strategic dimension, bringing substantial benefits to Europe, the USA and the worldwide user communities. Today the partnership covers back-up arrangements and data exchange for geostationary satellites and full sharing of low Earth orbit satellite systems, with the Initial Joint Polar System and the Jason series. With this agreement, we have established a policy framework to further develop our cooperation into the next decades.”

Key successes of the NOAA-EUMETSAT partnership include:

NOAA and EUMETSAT operate a joint polar satellite system, where EUMETSAT’s Metop satellites fly in the mid-morning orbit, while NOAA’s polar satellites and the Suomi NPP spacecraft fly in the afternoon orbit. Both agencies share all the data, which form the backbone of all medium range weather forecasts in the United States and Europe and make up the majority of the data used by the U.S. weather model (GFS) and the major European weather model (ECMWF).NOAA instruments fly onboard the EUMETSAT satellites, and EUMETSAT instruments are on the NOAA spacecraft, providing cost savings and more uniform datasets for meteorologists and scientists across continents.NOAA and EUMETSAT also exchange data from geostationary satellites, and have a back-up agreement in place for data sharing should either agency’s spacecraft experience trouble.The partnership also extends to the Jason-2 ocean surface topography mission that has been crucial to improvements in weather modeling and tropical storm intensification forecasting, and is supporting the EU-led Copernicus Earth Observation program with data from the Suomi NPP satellite.

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. For more information about NOAA satellites, please visit: www.nesdis.noa.gov and follow us on Facebook, Twitter and our other social media channels.

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National Weather Service more than doubles computing capacity

July 29, 2013

This is the Hurricane Weather Research and Forecasting (HWRF) model showing the Tropical Storm Flossie precipitation forecast for the Hawaiian Islands on July 29, 2013. HWRF is one of the sophisticated numerical computer models now being run on NOAA's new supercomputers.

Download here (Credit: NOAA)

Whizzing through 213 trillion calculations per second, newly upgraded supercomputers of NOAA’s National Weather Service are now more than twice as fast in processing sophisticated computer models to provide more accurate forecasts further out in time. And as the hurricane season ramps up, forecasters will be armed with an enhanced hurricane model that will improve track and intensity forecasts.

The scientific data and insights that these newly upgraded supercomputers will provide are essential to help government officials, communities, and businesses better understand and manage the risks associated with extreme weather and water events. In support of the president’s Climate Action Plan, the administration will continue to take steps like this to analyze and predict climate variability amid an increasing number of extreme natural events affecting the nation.

“These improvements are just the beginning and build on our previous success. They lay the foundation for further computing enhancements and more accurate forecast models that are within reach,” said Louis W. Uccellini, Ph.D., director of NOAA’s National Weather Service. “These upgrades are a game-changer for the entire public and private weather industry. In addition to the benefits to our own forecasters and products, we will provide our private sector partners with better information to empower them to enhance their services.”

Nicknamed “Tide,” the supercomputer in Reston, Va., and its Orlando-based backup named “Gyre,” are operating with 213 teraflops (TF) — up from the 90 TF with the computers that preceded them. This higher processing power allows the National Weather Service to implement an enhanced Hurricane Weather Research and Forecasting (HWRF) model.

"These forecasting advances can save lives,” said U.S. Sen. Bill Nelson, who helped get funding to add even more capacity to the supercomputer. “It's going to allow for better tracking of life-threatening storms and more accurately predict when and where they'll hit, and with what intensity."

With improved physics and a storm-tracking algorithm, the model has displayed up to a 15 percent improvement in both track and intensity forecasts, compared to last year's version of the model. The upgraded HWRF is also capable of processing real-time data collected from the inner core of a tropical system by the tail Doppler radar attached to NOAA’s P3 hurricane hunter aircraft, data which are expected to produce even greater forecast improvements.

“Next comes the quantum leap,” added Uccellini. Following this round of long-planned upgrades, funding requested in the FY 2014 President’s Budget, in addition to funding provided to NOAA by Congress in the spring of 2013 as part of the Hurricane Sandy emergency supplemental appropriations bill, would increase computing power even further to 1,950 TF by summer 2015. “That gives us the necessary computer power to run an enhanced version of our primary forecast model, the Global Forecast System,” said Uccellini.

"Given recent events like the tornado in Moore, Oklahoma or Superstorm Sandy, federal weather resources and personnel should be considered vital national assets. These upgrades assure world-class capabilities and a continued pathway to keep American lives and property safer," said J. Marshall Shepherd Ph.D., president of the American Meteorological Society and Professor at the University of Georgia. "As a father of two children and a scientist that understands looming weather threats, I take comfort in these developments."

Investments in supercomputing power for weather prediction are another step in NOAA’s efforts to build a Weather-Ready Nation. NOAA’s Weather-Ready Nation initiative, launched nearly two-years ago, has resulted in improvements in products, services and the way information is communicated to the public and partners. These improvements increase resilience to severe weather and reduce the potential of significant societal and economic impacts from severe weather.  A Weather-Ready Nation is a society that is prepared for, and responds effectively to, weather-related events.

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels.

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New analyses find evidence of human-caused climate change in half of the 12 extreme weather and climate events analyzed from 2012

September 5, 2013

The "Explaining Extreme Events of 2012 from a Climate Perspective" report was published today by the Bulletin of the American Meteorological Society. (Full report).

High resolution (Credit: U.S. Navy)

Human influences are having an impact on some extreme weather and climate events, according to the report “Explaining Extreme Events of 2012 from a Climate Perspective” released today by the Bulletin of the American Meteorological Society. Overall, 18 different research teams from around the world contributed to the peer-reviewed report that examined the causes of 12 extreme events that occurred on five continents and in the Arctic during 2012. Scientists from NOAA served as three of the four lead editors on the report.
The report shows that the effects of natural weather and climate fluctuations played a key role in the intensity and evolution of the 2012 extreme events. However, in some events, the analyses revealed compelling evidence that human-caused climate change, through the emission of heat-trapping gases, also contributed to the extreme event.

“This report adds to a growing ability of climate science to untangle the complexities of understanding natural and human-induced factors contributing to specific extreme weather and climate events,” said Thomas R. Karl, L.H.D, director of NOAA’s National Climatic Data Center (NCDC). “Nonetheless, determining the causes of extreme events remains challenging.”

In addition to investigating the causes of these extreme events, the multiple analyses of four of the events — the warm temperatures in the United States, the record-low levels of Arctic sea ice, and the heavy rain in both northern Europe and eastern Australia — allowed the scientists to compare and contrast the strengths and weaknesses of their various methods of analysis. Despite their different strategies, there was considerable agreement between the assessments of the same events.

Thomas Peterson, Ph.D., principal scientist at NOAA’s NCDC and one of the lead editors on the report, said, “Scientists around the world assessed a wide variety of potential contributing factors to these major extreme events that, in many cases, had large impacts on society. Understanding the range of influences on extreme events helps us to better understand how and why extremes are changing."

Key findings include:

Location and type of events analyzed in the Paper.

High resolution (Credit: NOAA)

Heat Wave and Drought in United States:

Human-induced climate change had little impact on the lack of precipitation in the central United States in 2012.The 2012 spring and summer heat waves in the U.S. can be mainly explained by natural atmospheric dynamics, however, human-induced climate change was found to be a factor in the magnitude of warmth and was found to have affected the likelihood of such heat waves.  For example: High temperatures, such as those experienced in the U.S. in 2012 are now likely to occur four times as frequently due to human-induced climate change.Approximately 35 percent of the extreme warmth experienced in the eastern U.S. between March and May 2012 can be attributed to human-induced climate change.  

Hurricane Sandy Inundation Probability:

The record-setting impacts of Sandy were largely attributable to the massive storm surge and resulting inundation from the onshore-directed storm path coincident with high tide. However, climate-change related increases in sea level have nearly doubled today’s annual probability of a Sandy-level flood recurrence as compared to 1950. Ongoing natural and human-induced forcing of sea level ensures that Sandy-level inundation events will occur more frequently in the future from storms with less intensity and lower storm surge than Sandy. 

Arctic Sea Ice:

The extremely low Arctic sea ice extent in summer 2012 resulted primarily from the melting of younger, thin ice from a warmed atmosphere and ocean. This event cannot be explained by natural variability alone. Summer Arctic sea ice extent will continue to decrease in the future, and is expected to be largely absent by mid-century.  

Global Rainfall Events:

The unusually high amount of summer rainfall in the United Kingdom in 2012 was largely the result of natural variability. However, there is evidence that rainfall totals are influenced by increases in sea surface temperature and atmospheric moisture which may be linked to human influences on climate.The magnitude of the extreme rainfall experienced over southeastern Australia between October 2011 and March 2012 was mainly associated with La Niña conditions. However, the likelihood of above-average precipitation during March was found to have increased by 5 percent to 15 percent because of human influences on the climate. Extreme rainfall events such as the December 2011 two-day rainfall in Golden Bay, New Zealand, are more likely to occur due to a 1 percent to 5 percent increase in available moisture resulting from increased levels of greenhouse gases in the atmosphere.The July 2012 extreme rainfall events in North China and southwestern Japan were mainly due to natural variability. 

The report was edited by Peterson, along with Martin P. Hoerling, NOAA’s Earth System Research Laboratory; Peter A. Stott, UK Met Office Hadley Centre and Stephanie C. Herring of NCDC and written by 78 scientists from 11 countries. View the full report online.

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Weather phobias

[This is a repost of an entry which had outdated links. That original entry and reader comments are here.]

As is mentioned in my bio, my desire to become a meteorologist was rooted in a phobia of thunder and lightning. A lot of kids are scared of thunderstorms, but mine went way beyond a normal childhood fear. I was petrified at the sound of thunder or the flash of lightning, especially at night.

I'm not sure exactly how old I was, but probably sometime during elementary school age I snuck into my parents' room and hid under their bed all night because I was worried there MIGHT be a thunderstorm.

My father, upon awakening in the morning, couldn't find me. Finally he did. The subsequent exchange went something like this:

"What in the world are you doing under there?!"

"I was worried there'd be a thunderstorm."

"But Stu, there's not a cloud in the sky!"

That fright is what triggered my curiosity, fascination, and even obsession with the weather. It has lasted my whole life. Fortunately, my phobia has not, although in certain situations lightning still makes me more uneasy than most people. For awhile I actually went too far in the other direction and became a little too nonchalant ... until a couple of close calls jolted me (figuratively, fortunately not literally).

With that background, I was quite interested to hear about a new study on weather phobias (focusing specifically on severe thunderstorms and tornadoes).

There even used to be a website (now defunct) which was exclusively devoted to storm phobias, and I'm certainly not the only one who has experienced some of these phobic symptoms!

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