Electromagnetic waves linked to particle fallout in Earth's atmosphere, new study finds

In a new study that sheds light on space weather's impact on Earth, Dartmouth researchers and their colleagues show for the first time that plasma waves buffeting the planet's radiation belts are responsible for scattering charged particles into the atmosphere.

The study is the most detailed analysis so far of the link between these waves and the fallout of electrons from the planet's radiation belts. The belts are impacted by fluctuations in "space weather" caused by solar activity that can disrupt GPS satellites, communication systems, power grids and manned space exploration.

The results appear in the journal Geophysical Research Letters. A PDF is available on request.

The Dartmouth space physicists are part of a NASA-sponsored team that studies the Van Allen radiation belts, which are donut-shaped belts of charged particles held in place by Earth's magnetosphere, the magnetic field surrounding our planet. In a quest to better predict space weather, the Dartmouth researchers study the radiation belts from above and below in complementary approaches -- through satellites (the twin NASA Van Allen Probes) high over Earth and through dozens of instrument-laden balloons (BARREL, or Balloon Array for Radiation belt Relativistic Electron Losses) at lower altitudes to assess the particles that rain down.

The Van Allen Probes measure particle, electric and magnetic fields, or basically everything in the radiation belt environment, including the electrons, which descend following Earth's magnetic field lines that converge at the poles. This is why the balloons are launched from Antarctica, where some of the best observations can be made. As the falling electrons collide with the atmosphere, they produce X-rays and that is what the balloon instruments are actually recording.

"We are measuring those atmospheric losses and trying to understand how the particles are getting kicked into the atmosphere," says co-author Robyn Millan, an associate professor in Dartmouth's Department of Physics and Astronomy and the principal investigator of BARREL. "Our main focus has been really on the processes that are occurring out in space. Particles in the Van Allen belts never reach the ground, so they don't constitute a health threat. Even the X-rays get absorbed, which is why we have to go to balloon altitudes to see them."

In their new study, the BARREL researchers' major objective was to obtain simultaneous measurements of the scattered particles and of ionoized gas called plasma out in space near Earth's equator. They were particularly interested in simultaneous measurements of a particular kind of plasma wave called electromagnetic ion cyclotron waves and whether these waves were responsible for scattering the particles, which has been an open question for years.

The researchers obtained measurements in Antarctica in 2013 when the balloons and both the Geostationary Operational Environmental Satellite (GOES) and Van Allen Probe satellites were near the same magnetic field line. They put the satellite data into their model that tests the wave-particle interaction theory, and the results suggest the wave scattering was the cause of the particle fallout. "This is the first real quantitative test of the theory," Millan says.

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Temperature anomalies are warming faster than Earth's average, study finds

It's widely known that Earth's average temperature has been rising. But research by an Indiana University geographer and colleagues finds that spatial patterns of extreme temperature anomalies -- readings well above or below the mean -- are warming even faster than the overall average.

And trends in extreme heat and cold are important, said Scott M. Robeson, professor of geography in the College of Arts and Sciences at IU Bloomington. They have an outsized impact on water supplies, agricultural productivity and other factors related to human health and well-being.

"Average temperatures don't tell us everything we need to know about climate change," he said. "Arguably, these cold extremes and warm extremes are the most important factors for human society."

Robeson is the lead author of the article "Trends in hemispheric warm and cold anomalies," which will be published in the journal Geophysical Research Letters and is available online. Co-authors are Cort J. Willmott of the University of Delaware and Phil D. Jones of the University of East Anglia.

The researchers analyzed temperature records for the years 1881 to 2013 from HadCRUT4, a widely used data set for land and sea locations compiled by the University of East Anglia and the U.K. Met Office. Using monthly average temperatures at points across the globe, they sorted them into "spatial percentiles," which represent how unusual they are by their geographic size.

Their findings include:

Temperatures at the cold and warm "tails" of the spatial distribution -- the 5th and 95th percentiles -- increased more than the overall average Earth temperature.Over the 130-year record, cold anomalies increased more than warm anomalies, resulting in an overall narrowing of the range of Earth's temperatures.In the past 30 years, however, that pattern reversed, with warm anomalies increasing at a faster rate than cold anomalies. "Earth's temperature was becoming more homogenous with time," Robeson said, "but now it's not."

The study records separate results for the Northern and Southern Hemispheres. Temperatures are considerably more volatile in the Northern Hemisphere, an expected result because there's considerably less land mass in the South to add complexity to weather systems.

The study also examined anomalies during the "pause" in global warming that scientists have observed since 1998. While a 16-year-period is too short a time to draw conclusions about trends, the researchers found that warming continued at most locations on the planet and during much of the year, but that warming was offset by strong cooling during winter months in the Northern Hemisphere.

"There really hasn't been a pause in global warming," Robeson said. "There's been a pause in Northern Hemisphere winter warming."

Co-author Jones of the University of East Anglia said the study provides scientists with better knowledge about what's taking place with Earth's climate. "Improved understanding of the spatial patterns of change over the three periods studied are vital for understanding the causes of recent events," he said.

It may seem counterintuitive that global warming would be accompanied by colder winter weather at some locales. But Robeson said the observation aligns with theories about climate change, which hold that amplified warming in the Arctic region produces changes in the jet stream, which can result in extended periods of cold weather at some locations in the mid-northern latitudes.

And while the rate of planetary warming has slowed in the past 16 years, it hasn't stopped. The World Meteorological Organization announced this month that 2014 is on track to be one of the warmest, if not the warmest, years on record as measured by global average temperatures.

In the U.S., the East has been unusually cold and snowy in recent years, but much of the West has been unusually warm and has experienced drought. And what happens here doesn't necessarily reflect conditions on the rest of the planet. Robeson points out that the United States, including Alaska, makes up only 2 percent of Earth's surface.

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Global warming will not reduce deaths in the winter months, British study concludes

New information released today finds that global warming is not likely to lessen britain's excess winter dying rate as formerly thought. The research is released within the journal Character Global Warming and debunks the broadly held view that warmer winters will cut the amount of deaths normally seen in the very coldest season.

Examining data in the past six decades, scientists in the College of Exeter and College College London (UCL) checked out the way the winter dying rate has transformed with time, and just what factors affected it.

They discovered that from 1951 to 1971, the amount of cold winter days was strongly associated with dying rates, while from 1971 to 1991, both the amount of cold days and flu activity were accountable for elevated dying rates. However, their analysis demonstrated that from 1991 to 2011, flu activity alone was the primary cause in year upon year variation in the winter months mortality.

Lead investigator Dr Philip Staddon stated "We have proven that the amount of cold days inside a winter no more describes its quantity of excess deaths. Rather, the primary reason for year upon year variation in the winter months mortality in recent decades continues to be flu."

They claim that this reduced outcomes of the amount of cold days and deaths inside a winter could be described by enhancements in housing, healthcare, earnings along with a greater understanding of the potential risks from the cold.

As global warming progresses, the United kingdom will probably experience growing weather extremes, including more less foreseeable periods of utmost cold. The study highlights that, despite a generally warmer winter, a far more volatile climate could really result in elevated amounts of winter deaths connected with global warming, instead of less.

Dr Staddon thinks the findings have important implications for policy:

"Both policy makers and health care professionals have, for a while, assumed that the potential take advantage of global warming is a decrease in deaths seen over winter. We have proven this is not likely to be. Efforts to combat winter mortality because of cold spells shouldn't be lessened, and individuals against flu and flu-like ailments ought to be maintained."

Co-author, Prof Hugh Montgomery of UCL stated:

"Global warming seems unlikely to reduce winter dying rates. Indeed, it might substantially increase them by driving extreme weather occasions and greater variation in the winter months temps. Action must automatically get to prevent this happening."

Co-author, Prof Michael Depledge of College of Exeter School Of Medicine stated:

"Studies from the kind we've carried out provide information that's key for policymakers and political figures planning to handle the impacts of global warming. We are hopeful that the significance of this problem is going to be understood, to ensure that matters of health insurance and environment security could be worked with seriously and effectively."

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Extreme weather triggered by global warming decides distribution of bugs, study shows

As global warming is advancing, the temperature in our planet increases. Many of the essential for the big number of creatures which are cold-blooded (ectothermic), including bugs. Their body's temperature is ultimately based on the ambient temperature, and also the same therefore is applicable towards the efficiency and speed of the vital biological processes.

But could it be alterations in climate or frequency of utmost temperature problems that possess the finest effect on species distribution? It was the questions that several Danish and Australian scientists made the decision to look at in many insect species.

Johannes Overgaard, Department of Bioscience, Aarhus College, Denmark, Michael R. Kearney and Ary A. Hoffmann, Melbourne College, Australia, lately released the outcomes of those studies within the journal Global Change Biology. The outcomes demonstrate that it's particularly the extreme temperature occasions that comprise the distribution of both tropical and temperate species. Thus global warming affects ectotermic creatures mainly because more periods of utmost weather are required later on.

Fruit flies were patterned

The scientists examined 10 fruit fly types of the genus Drosophila modified to tropical and temperate parts of Australia. First they examined the temps that the species can sustain growth and reproduction, and they found the limitations of tolerance for cold and hot temps.

"This is actually the very first time ever where we've been in a position to compare the results of extremes and alterations in average conditions inside a rigorous manner across several species," mentions Ary Hoffmann.

According to this understanding and understanding from the present distribution from the 10 species then they examined if distribution was correlated towards the temps needed for growth and reproduction in other words restricted to their ability to tolerate extreme temperature conditions.

"The solution was unambiguous: it's the species' ability to tolerate very hot or cold days that comprise their present distribution," states Johannes Overgaard.

Therefore, it is the ultimate weather occasions, for example prolonged high temperatures or very cold weather, that amounted to the bugs their existence, not a rise in climate.

Drastic changes available

With this particular information in hands, the scientists could then model how distributions are required to alter if global warming continues for the following a century.

Most terrestrial creatures experience temperature variation on daily and periodic time scale, and they're modified to those conditions. Thus, for any species to keep its existence under different temperature conditions you will find two simple conditions that must definitely be met. First of all, the temperature should from time to time be so that the species can grow and reproduce, and next, the temperature must not be so extreme the population's survival is threatened.

In temperate climate for instance, you will find many species that are modified to pass through low temps during the cold months, after which grow and reproduce within the summer time. In warmer environments, the task might be quite contrary. Here, the species might endure high temps throughout the dry hot summer time, while growth and reproduction mainly happens throughout the mild and wet winter period.

The end result was discouraging for those 10 species.

"Global warming can lead to less cold days or weeks, and therefore allow species to maneuver toward greater latitudes. However global warming also results in a greater incidence to very hot days and our model therefore forecasts the distribution of those species will disappear to under half their present distribution"states Johannes Overgaard.

"Actually, our forecasts are that some species would disappear entirely within the next couple of decades, even whether they have a reasonably wide distribution that presently covers 100s of kilometers," adds Ary Hoffmann.

"Although no 10 species analyzed are usually regarded as either dangerous or advantageous microorganisms for human society, the outcomes indicate that distribution of numerous insect species is going to be transformed significantly, and it'll most likely also affect most of the species which have particular social or commercial importance ," finishes Johannes Overgaard.

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Periodic Arctic summer time ice extent still difficult to forecast, study states

Will next year's summer time Arctic ice extent be low or high? Can ship captains intend on moving the famous Northwest Passage -- an immediate shipping route from Europe to Asia over the Arctic Sea -- to reduce some time and fuel? New research states year-to-year predictions from the Arctic's summer time ice extent are not reliable.

Researchers in the National Ice and snow Data Center (NSIDC), College College London, College of Nh and College of Washington examined 300 summer time Arctic ocean ice predictions from 2008 to 2013 and located that predictions are very accurate when ocean ice the weather is near to the downward trend that's been noticed in Arctic ocean ice during the last 3 decades. However, predictions aren't so accurate when ocean ice the weather is abnormally greater or lower in comparison for this trend.

"We discovered that in a long time once the ocean ice extent departed strongly in the trend, such as with 2012 and 2013, forecasts unsuccessful no matter the technique accustomed to forecast the September ocean ice extent," stated Julienne Stroeve, a senior researcher at NSIDC and professor at College of school London. Stroeve is lead author from the study, released lately in Geophysical Research Letters.

"That downward trend reflects Arctic global warming, but what causes yearly versions round the trend are not as easy to pin lower," stated Lawrence Hamilton, co-author along with a investigator in the College of Nh. "This assortment of predictions from a variety of sources highlights where they are doing well, where more jobs are needed."

Arctic ocean ice cover develops each winter as sunset for many several weeks, and reduces each summer time because the sun increases greater within the northern sky. Every year, the Arctic ocean ice reaches its minimum extent in September. Researchers consider Arctic ocean ice like a sensitive climate indicator and track this minimum extent each year to ascertain if any trends emerge.

Multi-funnel passive microwave satellite instruments happen to be monitoring ocean ice extent since 1979. Based on the data, September ocean ice extent from 1979 to 2013 has rejected 13.7 percent per decade. The current years have proven a much more dramatic decrease in Arctic ice. In September 2012, Arctic ocean ice arrived at an archive minimum: 16 percent less than any previous September since 1979, and 45 percent less than the typical ice extent from 1981 to 2010.

Lengthy-term forecasts of summer time Arctic extent produced by global climate models (GCMs) claim that the downward trend will probably result in an ice-free Arctic summer time in the center of a lifetime. GCMs have been in overall agreement on lack of Arctic summer time ocean ice consequently of anticipated warming from the increase in green house gases this century.

Shorter-term predictions of summer time ice extent are not as easy to create but have reached popular. The diminishing ice has caught the interest of seaside towns within the Arctic and industries thinking about removing assets as well as in a shorter shipping route between Asia and europe.

Most of the predictions examined within the study centered on the condition from the ice cover just before the summer time melt season. Based on the study, including ocean ice thickness and concentration could enhance the periodic predictions.

"It might be also easy to predict ocean ice cover annually ahead of time rich in-quality findings of ocean ice thickness and snow cover within the whole Arctic," stated Cecilia Bitz, co-author and professor of atmospheric sciences in the College of Washington.

"Temporary forecasts are achievable, but challenges stay in predicting anomalous years, and there's an excuse for better data for initialization of forecast models," Stroeve stated. "Obviously there's always the problem that people cannot predict the elements, and summer time weather designs remain important."

The research examined predictions from study regarding Environment Arctic Change (SEARCH) Ocean Ice Outlook, a task that gathers and summarizes ocean ice predictions produced by ocean ice scientists and conjecture centers. Contributing factors towards the SEARCH Ocean Ice Outlook project employ a number of strategies to forecast the September ocean ice extent, varying from heuristic, to record, to stylish modeling approaches.

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Photo voltaic activity not really a key reason for global warming, study shows

Global warming is not strongly affected by versions in warmth in the sun, a brand new study shows.

The findings overturn a broadly held scientific view that extended periods of warm and cold temperature previously may have been triggered by periodic fluctuations in photo voltaic activity.

Research analyzing what causes global warming within the northern hemisphere in the last 1000 years has proven that before the year 1800, the important thing driver of periodic alterations in climate was volcanic eruptions. These often prevent sunlight reaching Earth, leading to awesome, drier weather. Since 1900, green house gases happen to be the responsible for global warming.

The findings reveal that periods of low sun activity shouldn't be envisioned having a sizable effect on temps on the planet, and therefore are likely to improve scientists' understanding which help climate predicting.

Researchers in the College of Edinburgh completed the research using records of past temps built with data from tree rings along with other historic sources. They in comparison this data record with computer-based types of past climate, featuring both significant and minor changes under the sun.

They discovered that their type of weak changes under the sun gave the very best correlation with temperature records, showing that photo voltaic activity has already established a small effect on temperature previously millennium.

The research, released in Character GeoScience, was based on natural Atmosphere Research Council.

Dr Andrew Schurer, from the College of Edinburgh's School of GeoSciences, stated: "So far, the influence from the sun on past climate continues to be poorly understood. Hopefully our new breakthroughs can help improve our knowledge of how temps have transformed in the last couple of centuries, and improve forecasts for the way they may develop later on. Links between your sun and anomalously cold winters within the United kingdom continue to be investigated."

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New study suggests coral reefs may be able to adapt to moderate climate change

October 29, 2013

A new modeling study shows that widespread bleaching events like this one in Thailand in 2010 will become more common in the future. However, the study also found signs corals may be adapting to warming -- the question is if it can be fast enough to keep up with the rate humans are burning fossil fuels.

High resolution (Credit:C. Mark Eakin/NOAA )

Coral reefs may be able to adapt to moderate climate warming, improving their chance of surviving through the end of this century, if there are large reductions in carbon dioxide emissions, according to a study funded by NOAA and conducted by the agency’s scientists and its academic partners. Results further suggest corals have already adapted to part of the warming that has occurred.

“Earlier modeling work suggested that coral reefs would be gone by the middle of this century. Our study shows that if corals can adapt to warming that has occurred over the past 40 to 60 years, some coral reefs may persist through the end of this century,” said study lead author Cheryl Logan, Ph.D., an assistant professor in California State University Monterey Bay’s Division of Science and Environmental Policy. The scientists from the university, and from the University of British Columbia, were NOAA’s partners in the study.

Warm water can contribute to a potentially fatal process known as coral “bleaching,” in which reef-building corals eject algae living inside their tissues. Corals bleach when oceans warm only 1-2°C (2-4°F) above normal summertime temperatures. Because those algae supply the coral with most of its food, prolonged bleaching and associated disease often kills corals.

The study, published online in the journal Global Change Biology, explores a range of possible coral adaptive responses to thermal stress previously identified by the scientific community. It suggests that coral reefs may be more resilient than previously thought due to past studies that did not consider effects of possible adaptation.

The study projected that, through genetic adaptation, the reefs could reduce the currently projected rate of temperature-induced bleaching by 20 to 80 percent of levels expected by the year 2100, if there are large reductions in carbon dioxide emissions.

“The hope this work brings is only achieved if there is significant reduction of human-related  emissions of heat-trapping gases,” said Mark Eakin, Ph.D., who serves as director of the NOAA Coral Reef Watch monitoring program, which tracks bleaching events worldwide. “Adaptation provides no significant slowing in the loss of coral reefs if we continue to increase our rate of fossil fuel use.”

“Not all species will be able to adapt fast enough or to the same extent, so coral communities will look and function differently than they do today,” CalState’s Logan said.

While this paper focuses on ocean warming, many other general threats to coral species have been documented to exist that affect their long-term survival, such as coral disease, acidification, and sedimentation. Other threats to corals are sea-level rise, pollution, storm damage, destructive fishing practices, and direct harvest for ornamental trade.

According to the Status of Coral Reefs of the World: 2000 report, coral reefs have been lost around the world in recent decades with almost 20 percent of reefs lost globally to high temperatures during the 1998-1999 El Niño and La Niña and an 80 percent percent loss of coral cover in the Caribbean was documented in a 2003 Science paper. Both rates of decline have subsequently been documented in numerous other studies as an on-going trend.

Tropical coral reef ecosystems are among the most diverse ecosystems in the world, and provide economic and social stability to many nations in the form of food security, where reef fish provide both food and fishing jobs, and economic revenue from tourism. Mass coral bleaching and reef death has increased around the world over the past three decades, raising questions about the future of coral reef ecosystems.

In the study, researchers used global sea surface temperature output from the NOAA/GFDL Earth System Model-2 for the pre-industrial period though 2100 to project rates of coral bleaching.

Because initial results showed that past temperature increases should have bleached reefs more often than has actually occurred, researchers looked into ways that corals may be able to adapt to warming and delay the bleaching process.

The article calls for further research to test the rate and limit of different adaptive responses for coral species across latitudes and ocean basins to determine if, and how much, corals can actually respond to increasing thermal stress.

In addition to Logan, the other authors of the paper were John Dunne, NOAA Geophysical Fluid Dynamics Laboratory; Eakin, NOAA’s Coral Reef Watch; and Simon Donner, Department of Geography at the University of British Columbia. NOAA’s Coral Reef Conservation Program funded the study.

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, Instagram and our other social media channels.

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Study shows deeper meltdown at Japan nuke reactor (AP)

TOKYO – Radioactive debris from melted fuel rods may have seeped deeper into the floor of a Japan's tsunami-hit nuclear reactor than previously thought, to within a foot from breaching the crucial steel barrier, a new simulation showed Wednesday.

The findings will not change the ongoing efforts to stabilize the reactors more than eight months after the Fukushima Dai-ichi plant was disabled, but they harshly depict the meltdowns that occurred and conditions within the reactors, which will be off-limits for years.

The plant operator Tokyo Electric Power Co. said its latest simulation showed fuel at the No. 1 reactor may have eroded part of the primary containment vessel's thick concrete floor. The vessel is a beaker-shaped steel container, set into the floor. A concrete foundation below that is the last manmade barrier before earth.

The fuel came within a foot of the container's steel bottom in the worst-case scenario but has been somewhat cooled, TEPCO's nuclear safety official Yoshihiro Oyama said at a government workshop. He said fuel rods in the No. 1 reactor were the worst damaged because it lost cooling capacity before the other two reactors, leaving its rods dry and overheated for hours before water was pumped in.

The nuclear crisis following the March 11 earthquake and tsunami caused massive radiation leaks and the relocation of some 100,000 people.

Another simulation on the structure released by the government-funded Japan Nuclear Energy Safety Organization, or JNES, said the erosion of the concrete could be deeper and the possibility of structural damage to the reactor's foundation needs to be studied.

JNES official Masanori Naito said the melting fuel rods lost their shape as they collapsed to the bottom of the vessel, then deteriorated into drops when water pumping resumed, and the fuel drops spattered and smashed against the concrete as they fell, Naito said.

TEPCO and government officials are aiming to achieve "cold shutdown" by the end of the year — a first step toward creating a stable enough environment for work to proceed on removing the reactors' nuclear fuel and closing the plant altogether.

The government estimates it will take 30 years or more to safely decommission Fukushima Dai-ichi.

Wednesday's simulations depict what happened early in the crisis and do not mean a recent deterioration of the No. 1 reactor. Oyama said, however, the results are based only on available data and may not match the actual conditions inside the reactors, which cannot be opened for years.

Some experts have raised questions about achieving the "cold shutdown," which means bringing the temperature of the pressure vessel containing healthy fuel rods to way below the benchmark 100 Celsius (212 Fahrenheit). They say the fuel is no longer there and measuring the temperature of empty cores is meaningless, while nobody knows where and how hot the melted fuel really is.

Kiyoharu Abe, a nuclear expert at JNES, said it's too early to make a conclusion and more simulations should be done to get accurate estimates.

"I don't think the simulation today was wrong, but we should look at this from various viewpoints rather than making a conclusion from one simulation," Abe said. "It's just the beginning of a long process."

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