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Over demanding market affects fisheries more than climate change

Fisheries that rely on short life species, such as shrimp or sardine, have been more affected by climate change, because this phenomenon affects chlorophyll production, which is vital for phytoplankton, the main food for both species.

Disclosed by the research "Socioeconomic Impact of the global change over the fishing resources of the Mexican Pacific" headed by Ernesto A. Ch?vez Ortiz, from the National Polytechnic Institute (IPN).

Work performed at the Interdisciplinary Center of Marine Sciences (CICIMAR) from the IPN, indicates that in the last five years there have been no "spectacular" changes attributable to climate change, what has affected the fishing resources more is the over demanding market.

"Globally, a great part of the fishing resources is being exploited to its maximum capacity, several have overpass its regeneration capacities and are overexploited" Ch?vez Ortiz points out.

The specialist at CICIMAR details that the research consisted in exploratory weather and fisheries analysis, and confirmed what has been intuitively said for a while: a lot of the variability in the fishing is due to climate change, the problem is that evidence hadn't been found to prove it.

"In the research we found a clear and objective way to show it: we took historical data from FAO regarding fisheries, available since 1950, compared it to the data of weather variability and found high correlations.

Change patterns were identified, for example, while in the 70's the sardine production increases, in the 80's it decreases below average levels, meanwhile shrimp fishing increased above average but decreased in the 90's.

This way, climate changes were identified in the mid 70's and late 80's that affected the fishing of sardine and shrimp in the Mexican Pacific Ocean, possibly attributable to El Ni?o. In the particular case of the shrimp, it effects are related to an input of water from the continent; for example, when there's a good raining season, there will be an increase in the crustacean production, which is reduced when it doesn't rain.

The researcher at CICIMAR clarifies that the analysis of the fisheries, examined in the guidelines of this project, used of a simulation model that allows to evaluate optimal exploitation strategies, possible change in the biomass of the analyzed resources, as well as the long term effects of climate change, like cyclones, and set them apart of those caused by the intensity of the fishing.


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Gear up for flood risk this spring

The risk of flooding is rising nationwide as snow melt from heavy winter weather mixes with anticipated spring rains. Minor flooding is already reported in some areas of the country, including the Florida panhandle, Indiana and Illinois, and the National Weather Service predicts minor flooding across large areas of the Midwest and South, with heavier flooding likely in the upper Midwest and along the lower Mississippi River valley.

"Flooding can occur quickly, and we need to prepare for it, just as we need to prepare for other weather events such as hurricanes and tornadoes," said Sarah Nafziger, M.D., an emergency medicine physician at the University of Alabama at Birmingham and assistant state emergency medical services medical director for the Alabama Department of Public Health.

Nafziger says keeping informed is the key to staying safe during flooding events. Know your risk, pay attention to media reports, and have a plan.

"If flooding is expected in your area, plan an escape route that leads to higher ground, and prepare an emergency kit with first aid supplies and medicine, batteries, water, flashlights, and nonperishable food," she said. "Charge your electronic devices, and be ready to flee."

Nafziger says the National Weather Service website is a good source for additional recommendations before, during and after flooding; these include avoiding flood waters, heeding road closings and cautionary signs, and waiting for an official "all clear" before returning to a flooded area.

"The aftermath of flood can be just as dangerous as the actual flooding, with disease, electrical hazards and even displaced animals as threats," Nafziger said.


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Appearance of night-shining clouds has increased

First spotted in 1885, silvery blue clouds sometimes hover in the night sky near the poles, appearing to give off their own glowing light. Known as noctilucent clouds, this phenomenon began to be sighted at lower and lower latitudes -- between the 40th and 50th parallel -- during the 20th century, causing scientists to wonder if the region these clouds inhabit had indeed changed -- information that would tie in with understanding the weather and climate of all Earth.

A NASA mission called Aeronomy of Ice in the Mesosphere, or AIM, was launched in 2007 to observe noctilucent clouds, but it currently only has a view of the clouds near the poles. Now scientists have gathered information from several other missions, past and present, and combined it with computer simulations to systematically show that the presence of these bright shining clouds have indeed increased in areas between 40 and 50 degrees north latitude, a region which covers the northern third of the United Sates and the lowest parts of Canada. The research was published online in the Journal of Geophysical Research: Atmospheres on March 18, 2014.

"Noctilucent clouds occur at altitudes of 50 miles above the surface -- so high that they can reflect light from the sun back down to Earth," said James Russell, an atmospheric and planetary scientist at Hampton University in Hampton, Va., and first author on the paper. "AIM and other research has shown that in order for the clouds to form, three things are needed: very cold temperatures, water vapor and meteoric dust. The meteoric dust provides sites that the water vapor can cling to until the cold temperatures cause water ice to form."

To study long-term changes in noctilucent clouds, Russell and his colleagues used historical temperature and water vapor records and a validated model to translate this data into information on the presence of the clouds. They used temperature data from 2002 to 2011 from NASA's Thermosphere Ionosphere Mesosphere Energetics and Dynamics, or TIMED, mission and water vapor data from NASA's Aura mission from 2005 to 2011. They used a model previously developed by Mark Hervig, a co-author on the paper at GATS, Inc., in Driggs, Idaho.

The team tested the model by comparing its output to observations from the Osiris instrument on the Swedish Odin satellite, which launched in 2001, and the SHIMMER instrument on the U.S. Department of Defense STPSat-1 mission, both of which observed low level noctilucent clouds over various time periods during their flights. The output correlated extremely well to the actual observations, giving the team confidence in their model.

The model showed that the occurrence of noctilucent clouds had indeed increased from 2002 to 2011. These changes correlate to a decrease in temperature at the peak height where noctilucent clouds exist in the atmosphere. Temperatures at this height do not match temperatures at lower levels -- indeed, the coldest place in the atmosphere is at this height during summertime over the poles -- but a change there certainly does raise questions about change in the overall climate system.

Russell and his team will research further to determine if the noctilucent cloud frequency increase and accompanying temperature decrease over the 10 years could be due to a reduction in the sun's energy and heat, which naturally occurred as the solar output went from solar maximum in 2002 to solar minimum in 2009.

"As the sun goes to solar minimum, the solar heating of the atmosphere decreases, and a cooling trend would be expected," said Russell.

NASA's Goddard Space Flight Center in Greenbelt, Md. manages the TIMED mission for the agency's Science Mission Directorate at NASA Headquarters in Washington. The spacecraft was built by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.


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Climatologists offer explanation for widening of Earth's tropical belt

A cool-water anomaly known as La Ni?a occupied the tropical Pacific Ocean throughout 2007 and early 2008. In April 2008, scientists at NASA’s Jet Propulsion Laboratory announced that while the La Ni?a was weakening, the Pacific Decadal Oscillation (PDO) -- a larger-scale, slower-cycling ocean pattern—had shifted to its cool phase. This image shows the sea surface temperature anomaly in the Pacific Ocean from April 14–21, 2008. Places where the Pacific was cooler than normal are blue, places where temperatures were average are white, and places where the ocean was warmer than normal are red. The broad area of cooler-than-average water off the coast of North America from Alaska (top center) to the equator is a classic feature of the cool phase of the PDO. The cool waters wrap in a horseshoe shape around a core of warmer-than-average water. (In the warm phase, the pattern is reversed). Unlike El Ni?o and La Ni?a, which may occur every 3 to 7 years and last from 6 to 18 months, the PDO can remain in the same phase for 20 to 30 years. The shift in the PDO can have significant implications for global climate.Credit: NASA image by Jesse Allen, AMSR-E data processed and provided by Chelle Gentemann and Frank Wentz, Remote Sensing Systems Recent studies have shown that Earth's tropical belt -- demarcated, roughly, by the Tropics of Cancer and Capricorn -- has progressively expanded since at least the late 1970s. Several explanations for this widening have been proposed, such as radiative forcing due to greenhouse gas increase and stratospheric ozone depletion.

Now, a team of climatologists, led by researchers at the University of California, Riverside, posits that the recent widening of the tropical belt is primarily caused by multi-decadal sea surface temperature variability in the Pacific Ocean. This variability includes the Pacific Decadal Oscillation (PDO), a long-lived El Ni?o-like pattern of Pacific climate variability that works like a switch every 30 years or so between two different circulation patterns in the North Pacific Ocean. It also includes, the researchers say, anthropogenic pollutants, which act to modify the PDO.

Study results appear March 16 in Nature Geoscience.

"Prior analyses have found that climate models underestimate the observed rate of tropical widening, leading to questions on possible model deficiencies, possible errors in the observations, and lack of confidence in future projections," said Robert J. Allen, an assistant professor of climatology in UC Riverside's Department of Earth Sciences, who led the study. "Furthermore, there has been no clear explanation for what is driving the widening."

Now Allen's team has found that the recent tropical widening is largely driven by the PDO.

"Although this widening is considered a 'natural' mode of climate variability, implying tropical widening is primarily driven by internal dynamics of the climate system, we also show that anthropogenic pollutants have driven trends in the PDO," Allen said. "Thus, tropical widening is related to both the PDO and anthropogenic pollutants."

Widening concerns

Tropical widening is associated with several significant changes in our climate, including shifts in large-scale atmospheric circulation, like storm tracks, and major climate zones. For example, in Southern California, tropical widening may be associated with less precipitation.

Of particular concern are the semi-arid regions poleward of the subtropical dry belts, including the Mediterranean, the southwestern United States and northern Mexico, southern Australia, southern Africa, and parts of South America. A poleward expansion of the tropics is likely to bring even drier conditions to these heavily populated regions, but may bring increased moisture to other areas.

Widening of the tropics would also probably be associated with poleward movement of major extratropical climate zones due to changes in the position of jet streams, storm tracks, mean position of high and low pressure systems, and associated precipitation regimes. An increase in the width of the tropics could increase the area affected by tropical storms (hurricanes), or could change climatological tropical cyclone development regions and tracks.

Belt contraction

Allen's research team also showed that prior to the recent (since ~1980 onwards) tropical widening, the tropical belt actually contracted for several decades, consistent with the reversal of the PDO during this earlier time period.

"The reversal of the PDO, in turn, may be related to the global increase in anthropogenic pollutant emissions prior to the ~ early 1980s," Allen said.

Analysis

Allen's team analyzed IPCC AR5 (5th Assessment Report) climate models, several observational and reanalysis data sets, and conducted their own climate model experiments to quantify tropical widening, and to isolate the main cause.

"When we analyzed IPCC climate model experiments driven with the time-evolution of observed sea surface temperatures, we found much larger rates of tropical widening, in better agreement to the observed rate--particularly in the Northern Hemisphere," Allen said. "This immediately pointed to the importance of sea surface temperatures, and also suggested that models are capable of reproducing the observed rate of tropical widening, that is, they were not 'deficient' in some way."

Encouraged by their findings, the researchers then asked the question, "What aspect of the SSTs is driving the expansion?" They found the answer in the leading pattern of sea surface temperature variability in the North Pacific: the PDO.

They supported their argument by re-analyzing the models with PDO-variability statistically removed.

"In this case, we found tropical widening -- particularly in the Northern Hemisphere -- is completely eliminated," Allen said. "This is true for both types of models--those driven with observed sea surface temperatures, and the coupled climate models that simulate evolution of both the atmosphere and ocean and are thus not expected to yield the real-world evolution of the PDO.

"If we stratify the rate of tropical widening in the coupled models by their respective PDO evolution," Allen added, "we find a statistically significant relationship: coupled models that simulate a larger PDO trend have larger tropical widening, and vice versa. Thus, even coupled models can simulate the observed rate of tropical widening, but only if they simulate the real-world evolution of the PDO."

Future work

Next, the researchers will be looking at how anthropogenic pollutants, by modifying the PDO and large scale weather systems, have affected precipitation in the Southwest United States, including Southern California.

"Future emissions pathways show decreased pollutant emissions through the 21st century, implying pollutants may continue to drive a positive PDO and tropical widening," Allen 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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Risk of dengue fever epidemic in Europe

The risk of dengue fever beginning to spread in Europe is imminent. According to researchers from Ume? University, this is no longer just an issue for the scientific community but also for politicians and policy makers, who need to be prepared and develop preventive measures.

With a changing climate and rising temperatures in Europe, the incidence of the Aedes aegypti mosquito has also increased. The mosquito is the main vector of dengue that can cause haemorrhagic fever. Although no outbreak of the disease has not yet occurred in Europe, researchers at the Epidemiology and Global Health unit at Ume? University claim that there is now good living conditions for the mosquito in Europe and that it is therefore only a matter of time before we see an epidemic here. The Aedes albopictus mosquito has already established itself in large parts of Europe. Even though it is not as competent a vector as Aedes aegypti, several domestic cases of the disease have been observed in countries such as France and Croatia.

"The last outbreak of dengue in Portuguese Madeira when several thousand became ill, shows that it is no longer a theoretical possibility that the disease can take hold in Europe. It is a reality that can strike at any time," says Raman Preet, researcher and scientific project manager of the Dengue Tools project at the Department of Epidemiology and Global Health, Ume? University. "When the disease shows up in Europe it has probably accompanied travelers in areas in the world where the disease is established. Then it will be spread with the help of the Aedes mosquito."

The risk for Swedish travelers to be infected by dengue is highest when going to Sri Lanka and Bangladesh, while most cases in Sweden stems from trips to Thailand. There is currently no vaccine that can protect against dengue, nor is there any treatment when the illness strikes. Symptoms are similar to those of severe cold with fever, headache, muscle and joint pain, or upset stomach. The disease can be life threatening when it affects children, the elderly and chronically ill. In severe cases it can develop into a hemorrhagic fever.

The previous models used to study the spread of dengue and especially the living conditions for the Aedes mosquito has taken up the average temperature in different areas. Jing Helmersson, PhD student within the EU-funded DT project at Ume? University, demonstrates in her studies that it is not enough. These calculations must also include the diurnal temperature distribution in different areas, and temporal trends when assessing the potential for an epidemic caused by dengue. Therefore, Jing Helmersson has developed a climate model with historical data from 1901 to the present day, whose projections extends to 2099. The results show a strong link between climate change and increased ability for mosquitoes to spread the disease in Europe.

"In our analyses, we can see that climate change, including the extreme weather with large daily temperature fluctuations in different areas of Europe, causes a large relative increase in the potential for epidemic spread of dengue fever," says Jing Helmersson. "It mainly concerns areas in southern and central Europe where the potential for proliferation previously has been small. At the same time we see that the spread potential will decrease in warm areas of the world, because the temperatures get too high."

Following the results of the research project, Jing Helmersson believes that it is important to continue with the mapping of future risks of dengue infection, especially in temperate regions of the Northern Hemisphere. Increased globalization and the influx of viruses carried by flight passengers further heightens the risks.

"Perhaps the most important of these studies is that they give us a better understanding of the risks of a future epidemic of dengue fever," says Jing Helmersson. "This type of modelling where we use weather and climate data makes it possible to forewarn the authorities in countries that are at risk of dengue epidemics, so that they in turn can prepare and start to act."

Story Source:

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


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Fierce 2012 magnetic storm just missed us: Earth dodged huge magnetic bullet from the sun

Earth dodged a huge magnetic bullet from the sun on July 23, 2012.

According to University of California, Berkeley, and Chinese researchers, a rapid succession of coronal mass ejections -- the most intense eruptions on the sun -- sent a pulse of magnetized plasma barreling into space and through Earth's orbit. Had the eruption come nine days earlier, it would have hit Earth, potentially wreaking havoc with the electrical grid, disabling satellites and GPS, and disrupting our increasingly electronic lives.

The solar bursts would have enveloped Earth in magnetic fireworks matching the largest magnetic storm ever reported on Earth, the so-called Carrington event of 1859. The dominant mode of communication at that time, the telegraph system, was knocked out across the United States, literally shocking telegraph operators. Meanwhile, the Northern Lights lit up the night sky as far south as Hawaii.

In a paper appearing today (Tuesday, March 18) in the journal Nature Communications, former UC Berkeley postdoctoral fellow and research physicist Ying D. Liu, now a professor at China's State Key Laboratory of Space Weather, UC Berkeley research physicist Janet G. Luhmann and their colleagues report their analysis of the magnetic storm, which was detected by NASA's STEREO A spacecraft.

"Had it hit Earth, it probably would have been like the big one in 1859, but the effect today, with our modern technologies, would have been tremendous," said Luhmann, who is part of the STEREO (Solar Terrestrial Observatory) team and based at UC Berkeley's Space Sciences Laboratory.

A study last year estimated that the cost of a solar storm like the Carrington Event could reach $2.6 trillion worldwide. A considerably smaller event on March 13, 1989, led to the collapse of Canada's Hydro-Quebec power grid and a resulting loss of electricity to six million people for up to nine hours.

"An extreme space weather storm -- a solar superstorm -- is a low-probability, high-consequence event that poses severe threats to critical infrastructures of the modern society," warned Liu, who is with the National Space Science Center of the Chinese Academy of Sciences in Beijing. "The cost of an extreme space weather event, if it hits Earth, could reach trillions of dollars with a potential recovery time of 4-10 years. Therefore, it is paramount to the security and economic interest of the modern society to understand solar superstorms."

Based on their analysis of the 2012 event, Liu, Luhmann and their STEREO colleagues concluded that a huge outburst on the sun on July 22 propelled a magnetic cloud through the solar wind at a peak speed of more than 2,000 kilometers per second -- four times the typical speed of a magnetic storm. It tore through Earth's orbit but, luckily, Earth and the other planets were on the other side of the sun at the time. Any planets in the line of sight would have suffered severe magnetic storms as the magnetic field of the outburst tangled with the planets' own magnetic fields.

The researchers determined that the huge outburst resulted from at least two nearly simultaneous coronal mass ejections (CMEs), which typically release energies equivalent to that of about a billion hydrogen bombs. The speed with which the magnetic cloud plowed through the solar wind was so high, they concluded, because another mass ejection four days earlier had cleared the path of material that would have slowed it down.

"The authors believe this extreme event was due to the interaction of two CMEs separated by only 10 to 15 minutes," said Joe Gurman, the project scientist for STEREO at NASA's Goddard Space Flight Center in Greenbelt, Md.

One reason the event was potentially so dangerous, aside from its high speed, is that it produced a very long-duration, southward-oriented magnetic field, Luhmann said. This orientation drives the largest magnetic storms when they hit Earth because the southward field merges violently with Earth's northward field in a process called reconnection. Storms that normally might dump their energy only at the poles instead dump it into the radiation belts, ionosphere and upper atmosphere and create auroras down to the tropics.

"These gnarly, twisty ropes of magnetic field from coronal mass ejections come blasting from the sun through the ambient solar system, piling up material in front of them, and when this double whammy hits Earth, it skews the Earth's magnetic field to odd directions, dumping energy all around the planet," she said. "Some of us wish Earth had been in the way; what an experiment that would have been."

"People keep saying that these are rare natural hazards, but they are happening in the solar system even though we don't always see them," she added. "It's like with earthquakes -- it is hard to impress upon people the importance of preparing unless you suffer a magnitude 9 earthquake."

All this activity would have been missed if STEREO A -- the STEREO spacecraft ahead of us in Earth's orbit and the twin to STEREO B, which trails in our orbit -- had not been there to record the blast.

The goal of STEREO and other satellites probing the magnetic fields of the sun and Earth is to understand how and why the sun sends out these large solar storms and to be able to predict them during the sun's 11-year solar cycle. This event was particularly unusual because it happened during a very calm solar period.

"Observations of solar superstorms have been extremely lacking and limited, and our current understanding of solar superstorms is very poor," Liu said. "Questions fundamental to solar physics and space weather, such as how extreme events form and evolve and how severe it can be at the Earth, are not addressed because of the extreme lack of observations."


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Linking storms to climate change a 'distraction', say experts

Connecting extreme weather to climate change distracts from the need to protect society from high-impact weather events which will continue to happen irrespective of human-induced climate change, say experts.

Writing in the journal Weather, Climate and Society, the University of Manchester researchers argue that cutting greenhouse gas emissions, while crucial to reducing humanity's longer-term impact on the planet, will not eliminate violent storms, tornadoes or flooding and the damage they cause.

The authors suggest that developing greater resilience to extreme weather events must be given greater priority if the socioeconomic impact of storms, like those that have ravaged Britain this winter, is to be reduced.

Professor David Schultz, one of the authors of the guest editorial, said: "One of the long-term effects of climate change is often predicted to be an increase in the intensity and frequency of many high-impact weather events, so reducing greenhouse gas emissions is often seen to be the response to the problem.

"Reducing humanity's impact on our planet should be pursued as a matter of urgency, but more emphasis must also be placed on being resilient to individual weather events, as this year's storms in Britain have so devastatingly shown."

In the past, say the authors, society responded to weather disasters with calls for greater resilience, but public awareness of humanmade climate change has given climate timescales (decades and centuries) far greater importance than weather timescales (days and years)

Schultz, a professor of synoptic meteorology, and co-author Dr Vladimir Jankovic, a science historian specialising in weather and climate, say the short-term, large variability from year to year in high-impact weather makes it difficult, if not impossible, to draw conclusions about the correlation to longer-term climate change.

They argue that while large public investments in dams and flood defences, for example, must account for the possibilities of how weather might change in the future, this should not prevent short-term thinking to address more immediate vulnerability to inevitable high-impact weather events.

"Avoiding construction in floodplains, implementing strong building codes, and increasing preparedness can make society more resilient to extreme weather events," said Dr Jankovic. "But compounding the problem is that finding money for recovery is easier than spending on prevention, even if the costs of recovery are much higher."

This bias, say the authors, has a tendency to diminish the political dedication for preventative measures against extreme weather, regardless of whether they are caused or intensified by humanmade influences. Yet, steps taken to protect society from the weather can protect the planet as well, they argue.

Dr Jankovic said: "Improving forecasting, increasing preparedness or building better infrastructure can increase resilience and reduce carbon-dioxide emissions. For example, greening neighbourhoods or painting roofs lighter colours will both reduce the urban heat-island effect and reduce carbon-dioxide emissions through reduced air-conditioning costs, while making cities more resistant to storm damage would reduce emissions generated from rebuilding devastated areas."

Professor Schultz added: "Linking high-impact weather events with climate change can be distracting; perpetuating the idea that reducing greenhouse gases would be enough to reduce increasingly vulnerable world populations, in our view, only confuses the public and policy-makers as to the socio-economic susceptibility to extreme weather.

"With or without mitigation, there is no quick-fix, single-cause solution for the problem of human vulnerability to socio-environmental change, nor is there a reasonable prospect of attenuating high-impact weather. Addressing such issues would give the world an opportunity to develop a two-pronged policy in climate security, reducing longer-term climate risks in conjunction with preventing shorter-term weather disasters."


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Microwave radar monitors sliding slopes: Geodesists research in the Alps

The "Steinlehnen" slope in Northern Tyrol (Austria) started to move in 2003. Rockfalls threatened people, streets and buildings. Meanwhile, peace has returned; although the slope is merely "creeping," Steinlehnen has become an interesting research object for scientists in recent years.

Professor Andreas Eichhorn of the Geodetic Measurement Systems and Sensors branch in the Department of Civil and Environmental Engineering at the Technical University of Darmstadt initiated the interdisciplinary project KASIP (Knowledge-based Alarm System with Identified Deformation Predictor) together with the Technical University of Vienna and the "alpS" research institute; the goal was to combine metrological observations of the slope with computer models.

"A slope is tremendously complex," says Eichhorn. It can be difficult to determine exactly how a mountain slope is composed and how a failure mechanism works in detail. Therefore, scientists will not be able to rely solely on computer-based models to predict mass movements in the future; they also need efficient and precise surveillance and monitoring systems that are as comprehensive as possible.

To do this, Eichhorn and his team tested different methods at Steinlehnen. "Installing sensors in highly active areas of the mountain is very dangerous," explains Eichhorn. "We were looking for a method that, among other things, makes non-contact observation possible." In the end, one method proved to be particularly suitable; although its basic physical principle has been used in geodesy for a long time, it was never used for the monitoring of slopes. This method uses a microwave radar of the Department of Physical Geodesy and Satellite Geodesy of the TU Darmstadt (Professor Matthias Becker), which was applied prototypically by Eichhorn's team of Darmstadt scientists.

Here, the entire surface of a slope is "shot" with microwaves that are reflected back from the surface and can then be analyzed. By comparing different measurements, the scientists can document changes of just a few millimeters. Accumulations or erosion of rock material, or even the beginning of a major landslide, can thus be recorded, Eichhorn says. In contrast to methods that scan the surface with laser light, for example, microwaves deliver much less disturbance. "A laser has too much noise," says Eichhorn. In her dissertation, doctoral candidate Sabine R?delsperger developed an evaluation strategy for interpreting the measured data; among other things, this also makes it possible to remove meteorological disturbances and to arrive at meaningful 3D images of the slope.

During the KASIP experiments, the geodesists from Darmstadt, together with their colleagues from the field of geophysics, achieved many important insights for the more accurate interpretation of observed geophysical phenomena and the correlation between the weather and the sliding behavior of the slope. But the research also has practical benefits, as Eichhorn explains: "Solely in terms of technology, it is possible to continuously monitor a large-scale critical slope in high-resolution. Accelerations -- early indicators of the possible slipping of large masses -- can be detected, and it can be determined when the slope stops moving."

Microwave radar devices are still very expensive, but the method already has potential as a good early warning system: "If you would observe critical slopes with them, you could reliably determine exactly where something is happening," says Eichhorn. "Then less expensive measurement systems and their sensors could be specifically applied there."


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NASA simulation portrays ozone intrusions from aloft

Outdoor enthusiasts in Colorado's Front Range are occasionally rewarded with remarkable visibility brought about by dry, clear air and wind. But it's what people in the mountainous U.S. West can't see in conditions like this -- ozone plunging down to the ground from high in the stratosphere, the second layer of the atmosphere -- that has attracted the interest of NASA scientists, university scientists and air quality managers.

Invisible Intruder

Ozone in the stratosphere, located on average 10 to 48 kilometers (6 to 30 miles) above the ground, typically stays in the stratosphere. Not on days like April 6, 2012.

On that day, a fast-moving area of low pressure moved northeast across states in the Western U.S., clipping western and northern Colorado. Ozone-rich stratospheric air descended, folding into tropospheric air near the ground. Winds took hold of the air mass and pushed it in all directions, bringing stratospheric ozone to the ground in Colorado and along the Northern Front Range. The event, called a stratospheric ozone intrusion, raised ground-level ozone concentrations in some areas to potentially unhealthy levels. Watch the intrusion unfold in a new NASA simulation of the event.

Ozone high in the atmosphere, in the stratosphere, forms naturally when sunlight mingles with oxygen molecules to form the well-known "layer" that protects life on Earth from the sun's harmful ultraviolet rays. That's in contrast to ozone near the ground, in the troposphere, which forms from complex reactions involving chemicals emitted from industrial processes, vehicle exhaust, and other byproducts of fossil fuel combustion. Ozone at ground level can damage lung tissue and pose an immediate threat to sensitive groups such as people with asthma.

For this reason, the Clean Air Act requires the U.S. Environmental Protection Agency to set a threshold for ground-level ozone, as outlined in the National Ambient Air Quality Standards. States that exceed this threshold can be fined, although the EPA can grant exceptions for natural events or those proven to be beyond reasonable control.

That's why ozone intrusions are on the minds of air quality managers like Patrick Reddy, lead forecast meteorologist at Colorado's Department of Public Health and Environment in Denver, Colo. Reddy co-leads the EPA Stratospheric Intrusion Work Group, tasked to identify ozone intrusion events and collect input for improved analysis.

The state of Colorado flagged the concentrations associated with the April 6 event as possibly exceeding the EPA's allowable threshold. Now it's up to Reddy and colleagues to determine if the intrusion on April 6 is a viable candidate for the preparation of documentation to be classified as an exceptional event.

"We need to use the best science that we can to demonstrate conclusively that 'but for' this intrusion there would not have been an exceedence," Reddy said.

Resolution Requirements

Reddy says it's fairly obvious when a stratospheric ozone intrusion has occurred, based on signatures in satellite data, air quality monitoring stations and meteorological data. For example, low water vapor, wind and high ozone at remote locations are often characteristic of stratospheric air.

Evidence of the intrusions, however, doesn't show up in the models currently used by air quality managers. Many of those models assume ozone moves from the stratosphere to the troposphere at a constant, average rate. This fails to capture the episodic intrusion events.

Meiyun Lin, an atmospheric scientist at Princeton University and NOAA's Geophysical Fluid Dynamics Laboratory (GFDL) in Princeton, New Jersey, set out to better quantify the impact of stratospheric ozone intrusions. Lin and colleagues used satellite and meteorological observations alongside a global chemistry-climate model to simulate intrusions in high-resolution.

Like the pixels in a photograph, the resolution of a model refers to the size of three-dimensional boxes of atmosphere. Models simulate the chemistry and atmospheric processes inside each box. For perspective, a model with 200-kilometer (124-mile) resolution is typical of today's high-end climate models, and 25-kilometer (16-mile) resolution is typical of high-end weather forecasts.

"We absolutely need to use a model with a grid size at least as small as, or smaller than, 50-by-50 kilometers (31-by-31 miles) to look at where and when the stratospheric air reaches the surface," Lin said.

Lin's analysis, based on a GFDL model with 50-kilometer (31-mile) resolution, suggests that the impact on ground level ozone in the U.S. West from springtime intrusion events is two to three times greater than previously estimated. The study was published October 2012 in Journal of Geophysical Research.

Steven Pawson and Eric Nielsen, atmospheric scientists at NASA's Goddard Space Flight Center in Greenbelt, Md., are also in pursuit of improved model simulations of stratospheric ozone intrusions. The team set out to see if the Goddard Earth Observing System Model, Version 5 (GEOS-5) Chemistry-Climate Model could replicate stratospheric intrusions at 25-kilometer (16-mile) resolution.

They show that indeed, the model could replicate small-scale features, including finger-like filaments, within the apron of ozone-rich stratospheric air that descended over Colorado on April 6, 2012.

"High-resolution modeling is giving us the capability to examine these events comprehensively for the first time," Nielsen said.

High-resolution models are possible due to computing power now capable of simulating the chemistry and movement of gasses and pollutants around the atmosphere and calculating their interactions. The addition of chemistry to these models, however, is not without a computational cost. For example, a weather forecast that takes about one hour of computational time would take five hours to run at the same resolution with the chemistry included.

"For a long time people thought excluding stratospheric chemistry was a reasonable approximation to make," said Lesley Ott, an atmospheric scientist at NASA Goddard. "But recent work has shown that you really need to consider what the stratosphere is doing. It's not just something you can totally ignore, despite the fact that it's more computationally intensive."

Atmospheric measurements from the ground and from aircraft suggest the higher resolution models are on track. In June and July 2011, NASA aircraft flew at low altitude over the Baltimore-Washington area as part of DISCOVER-AQ, a NASA airborne campaign to study urban air quality. Comparing data from the aircraft with the model output, Ott says the models performed well.

Tying it Together

Scientists already know that intrusions reaching surface air are more frequent in spring and early summer, when chemistry and weather conditions are more favorable for such events. Also, intrusions are more likely to affect mountainous regions in the U.S. West simply because land at elevation is closer to the stratosphere.

The next step is to find out how the frequency of intrusions changes from year to year and what controls its variability. "This is really the first time that our models are giving us the chance to try to answer those questions," Ott said.

Reddy, too, looks forward to seeing if the models can streamline reporting and forecasting efforts. "The nice thing about the new model products is that they could help us potentially do a better job forecasting these events and documenting what happened for those events that we want to submit to the EPA," he said.

The models could also help Reddy as his agency works to refine and expand its services. Models that could more accurately focus the timing and scale of intrusion effects would enhance the state's ability to issue advisories that better target affected populations.

Does that mean that spring skiers will have an additional forecast to consider before heading to the slopes?

"In the West, don't be surprised if on a clean-looking, windy day in spring there's an ozone health advisory," Reddy said.

As for Bryan Duncan, an atmospheric scientist at NASA Goddard, "It wouldn't stop me from enjoying the powder conditions."


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Conventional theories about Titanic disaster put on ice: Risk of icebergs higher now than in 1912

Academics at the University of Sheffield have dispelled a long-held theory that the Titanic was unlucky for sailing in a year with an exceptional number of icebergs and say the risk of icebergs is actually higher now.

Previously it had been suggested that the seas which sank the famous cruise ship -- which set off on its maiden voyage 102 years ago today (Thursday 10 April 2014) -- had an exceptional number of icebergs caused by lunar or solar effects.

But academics at the University have shown the ship wasn't voyaging in an extreme year.

Using data on iceberg locations dating back to 1913 -- recorded to help prevent a repeat of the Titanic -- they have shown that 1912 was a significant ice year but not extreme.

Professor Grant Bigg who led the research, said: "We have seen that 1912 was a year of raised iceberg hazard, but not exceptionally so in the long term. The year 1909 recorded a slightly higher number of icebergs and more recently the risk has been much greater -- between 1991 and 2000 eight of the ten years recorded more than 700 icebergs and five exceeded the 1912 total."

He added: "As use of the Arctic, in particular, increases in the future with the declining sea-ice the ice hazard will increase in water not previously used for shipping. As polar ice sheets are increasingly losing mass as well, the iceberg risk is likely to increase in the future, rather than decline."

The iceberg which sank the Titanic was spotted just before midnight on 14 April 1912 500m away. Despite quick action to slow the ship it wasn't enough and the ship sank in just two and a half hours. The disaster saw 1,517 people perish and only 700 survive.

Funding for the research, published in the journal Weather, was provided by the National Environment Research Council (NERC).


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