NASA simulation shows ozone makes use of from aloft

Outside fanatics in Colorado's Front Range are from time to time compensated with amazing visibility caused by dry, obvious air and wind. But it is what individuals within the mountainous U.S. West can't see in conditions such as this -- ozone plunging lower down from full of the stratosphere, the 2nd layer from the atmosphere -- which has attracted the eye of NASA researchers, college researchers and quality of air managers.

Invisible Burglar

Ozone within the stratosphere, situated normally 10 to 48 kilometers (6 to 30 miles) over the ground, typically stays within the stratosphere. This is not on days like April 6, 2012.

Tomorrow, a quick-moving section of low pressure moved northeast across states within the Western U.S., clipping western and northern Colorado. Ozone-wealthy stratospheric air descended, folding into tropospheric air close to the ground. Winds became predominant from the air mass and pressed it in most directions, getting stratospheric ozone down in Colorado and across the Northern Front Range. The big event, known as a stratospheric ozone invasion, elevated ground-level ozone levels in certain areas to potentially unhealthy levels. Watch the invasion unfold inside a new NASA simulation from the event.

Ozone full of the climate, within the stratosphere, forms naturally when sunlight mingles with oxygen molecules to create the well-known "layer" that safeguards existence on the planet in the sun's dangerous ultraviolet sun rays. That's as opposed to ozone close to the ground, within the troposphere, which forms from complex responses including chemicals released from industrial processes, vehicle exhaust, along with other off cuts of fossil fuel combustion. Ozone at walk out can harm lung tissue and pose an instantaneous threat to sensitive groups for example individuals with bronchial asthma.

Because of this, the Climate Act necessitates the U.S. Environment Protection Agency to create a threshold for ground-level ozone, as layed out within the National Ambient Quality Of Air Standards. Claims that exceed this threshold could be penalized, even though the Environmental protection agency can grant exceptions for natural occasions or individuals shown to be beyond reasonable control.

This is exactly why ozone makes use of are point of interest of quality of air managers like Patrick Reddy, lead forecast meteorologist at Colorado's Department of Public Health insurance and Atmosphere in Colorado, Colo. Reddy co-leads the Environmental protection agency Stratospheric Invasion Work Group, assigned to recognize ozone invasion occasions and collect input for enhanced analysis.

The condition of Colorado flagged the levels connected using the April 6 event as possibly exceeding the EPA's allowable threshold. Now it's as much as Reddy and co-workers to find out when the invasion on April 6 is a practicable candidate for that preparation of documentation to become considered a fantastic event.

"We have to make use of the best science that people can to show effectively that 'but for' this invasion there will not have been an exceedence," Reddy stated.

Resolution Needs

Reddy states it's fairly apparent whenever a stratospheric ozone invasion has happened, according to signatures in satellite data, quality of air monitoring stations and meteorological data. For instance, low water vapor, wind and ozone at remote locations are frequently sign of stratospheric air.

Proof of the makes use of, however, does not display in the models presently utilized by quality of air managers. A lot of individuals models assume ozone moves in the stratosphere towards the troposphere in a constant, average rate. This does not capture the episodic invasion occasions.

Meiyun Lin, an atmospheric researcher at Princeton College and NOAA's Geophysical Fluid Dynamics Laboratory (GFDL) in Princeton, Nj, set to better evaluate the outcome of stratospheric ozone makes use of. Lin and co-workers used satellite and meteorological findings alongside a worldwide chemistry-climate model to simulate makes use of in high-resolution.

Such as the pixels inside a photograph, the resolution of the model refers back to the size three-dimensional boxes of atmosphere. Models simulate the chemistry and atmospheric processes inside each box. For perspective, one with 200-kilometer (124-mile) resolution is normal of present day high-finish climate models, and 25-kilometer (16-mile) resolution is normal of high-finish weather predictions.

"We absolutely want to use one having a power grid size a minimum of no more than, or more compact than, 50-by-50 kilometers (31-by-31 miles) to check out when and where the stratospheric air reaches the top,Inch Lin stated.

Lin's analysis, with different GFDL model with 50-kilometer (31-mile) resolution, indicates the effect on walk out ozone within the U.S. West from spring invasion occasions is 2 to 3 occasions more than formerly believed. The research was released October 2012 in Journal of Geophysical Research.

Steven Pawson and Eric Nielsen, atmospheric researchers at NASA's Goddard Space Flight Center in Greenbelt, Md., will also be in search of enhanced model simulations of stratospheric ozone makes use of. They set to find out if the Goddard Earth Watching System Model, Version 5 (GEOS-5) Chemistry-Climate Model could replicate stratospheric makes use of at 25-kilometer (16-mile) resolution.

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

"High-resolution modeling is giving us the capacity to look at these occasions adequately the very first time,Inch Nielsen stated.

High-resolution models are possible because of computing energy now able to replicating the chemistry and movement of gasses and contaminants round the atmosphere and calculating their interactions. Adding chemistry to those models, however, isn't with no computational cost. For instance, a weather forecast that can take about 1 hour of computational time would take five hrs to operate in the same resolution using the chemistry incorporated.

"For any very long time people thought excluding stratospheric chemistry would be a reasonable approximation to create,Inch stated Lesley Ott, an atmospheric researcher at NASA Goddard. "But recent work has proven that you will need to consider exactly what the stratosphere does. It's not only something can totally ignore, even though it's more computationally intensive."

Atmospheric dimensions in the ground and from aircraft suggest the greater resolution models take presctiption track. In June and This summer 2011, NASA aircraft travelled at low altitude within the Baltimore-Washington area included in Uncover-AQ, a NASA airborne campaign to review urban quality of air. Evaluating data in the aircraft using the model output, Ott states the models carried out well.

Tying it Together

Researchers know that makes use of reaching surface air tend to be more frequent in spring and early summer time, when chemistry and conditions are better for such occasions. Also, makes use of may affect mountainous regions within the U.S. West due to the fact land at elevation is nearer to the stratosphere.

The next thing is to discover the way the frequency of makes use of changes from year upon year and just what controls its variability. "This is actually the very first time our models are giving us the opportunity to attempt to answer individuals questions," Ott stated.

Reddy, too, anticipates seeing when the models can streamline confirming and predicting efforts. "The excellent factor concerning the new model items is they may help us potentially perform a better job predicting these occasions and recording what went down for individuals occasions that you want to undergo the Environmental protection agency," he stated.

The models may also help Reddy as his agency activly works to refine and expand its services. Appliances could more precisely focus the timing and scale of invasion effects would boost the state's capability to problem advisories that better target affected populations.

Does which means that that spring snowboarders may have yet another forecast to think about before going to the slopes?

"In the western world, expect if on the clean-searching, windy day in spring likely to ozone health advisory," Reddy stated.

For Bryan Duncan, an atmospheric researcher at NASA Goddard, "It can't stop me from taking pleasure in the powder conditions."

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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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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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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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Paper shows Japan feared aftershocks at nuke plant (AP)

TOKYO – Japan feared three months after the Fukushima nuclear power plant was hit by a tsunami that aftershocks could further damage one of its fuel storage pools, causing rods inside to melt and spew radiation within hours, according to a newly released document.

The Japan Nuclear Energy Safety Organization said it carried out a simulation that showed some 1,500 mostly used fuel rods at the plant's No. 4 reactor building could start breaking in two hours if aftershocks further damaged the pool and caused cooling water to escape. The fuel rods could start melting within eight hours, the organization said in a report dated June 30 and published Friday.

The report shows that the pool remained vulnerable for nearly four months until its operator completed reinforcement work in July. Tokyo Electric Power Co. had said before then that the building could withstand major aftershocks without reinforcement, but made repairs after acknowledging structural damage and water leaks from the pool area.

The March 11 quake and tsunami triggered meltdowns at the plant's three reactors. Explosions also damaged their buildings, plus Unit 4 next to them.

The simulation was based on a scenario that cooling water was lost in the Unit 4 spent fuel storage pool, located on the top floor of the building. The Unit 4 pool was considered high risk as it contained more fuel than the other three pools, as it also stored fuel rods that had been moved from the unit's reactor core, which was being fitted with new parts.

In the report, the government-funded JNES said a loss of pool water due to additional cracks from aftershocks could cause the fuel rods to overheat. Their casings could break and start spewing radiation in about 2 hours. Fuel pellets inside each rod could start melting within 7.7 hours at about 2,800 Celsius (5,000 Fahrenheit), it said.

The report was part of hundreds of pages of documents containing simulation results on dozens of accident scenarios by JNES earlier in the crisis.

Plant workers are still struggling to contain radiation still leaking from the plant, although the amount is far less than before.

TEPCO said Friday that Unit 1 — one of the most damaged buildings — now has an outer shell made of airtight polyester designed to contain radioactive particles inside the building. Similar covers are also planned for other buildings.

Government officials are also making massive decontamination efforts in areas around the plant, from where tens of thousands of people had to evacuate.

Recent discoveries of radiation "hot spots" in and around Tokyo have also caused fears among people there, where many concerned parents routinely check their neighborhoods for radiation. In most cases the reading is estimated to be below the internationally accepted annual limit, but critics say the standard exceeds Japan's cap before the accident and the government should expand the scope of decontamination.

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U.N. nuclear report shows Japan safety shortcomings (Reuters)

VIENNA (Reuters) – Japanese nuclear regulators failed to review and approve steps taken after 2002 to protect against tsunamis at the Fukushima plant and these proved insufficient to prevent the tidal wave disaster three months ago, a U.N. report showed.

A detailed assessment by experts from the International Atomic Energy Agency -- the first outside review of Japan's nuclear crisis -- suggested several shortcomings both before and after a tidal wave crippled the power station three months ago.

But it also praised the way workers on the ground dealt with the situation at Fukushima Daiichi after the massive earthquake and huge tsunami devastated its reactors on March 11, triggering the world's worst nuclear catastrophe in a quarter of a century.

Given the extreme circumstances it is doubtful "that any better solutions than the ones actually chosen could have been realistically implemented," said the 160-page report, prepared for a ministerial nuclear safety meeting in Vienna next week.

A three-page summary was issued at the end of the 18-member team's May 24-June 2 inspector mission to Japan. It said the country underestimated the threat from tsunamis to the Fukushima plant and urged sweeping changes to its regulatory system.

Japanese authorities have been criticized for failing to plan for a tsunami that would surge over the 5.7 meter (19-ft) wall at the nuclear power station in the country's northeast, despite warnings that such a risk was looming.

The wave that crashed into the complex after the 9.0 magnitude earthquake was about 14 meters (46 feet) high.

In another setback to efforts to restore control over the quake-stricken plant, a rise in radiation halted the clean-up of radioactive water at Fukushima on Saturday only hours after it got under way.

The full IAEA report said there had been "insufficient defense-in-depth provisions" for tsunami hazards, even though they had been considered in the design and siting of the plant operated by Tokyo Electric Power Company, or Tepco.

DECISION DELAYS

Extra protective steps were taken as a result of an evaluation after 2002 -- the projected tsunami height was increased -- but they were insufficient "to cope with the high tsunami run-up values and all associated hazardous phenomena."

"Moreover, those additional protective measures were not reviewed and approved by the regulatory authority," said the report. It added: "Severe accident management provisions were not adequate to cope with multiple plant failures."

The document, obtained by Reuters, was submitted to IAEA member states on Friday but has not yet been made public.

At the June 20-24 IAEA-hosted meeting, some 150 nations will begin charting a strategy on boosting global nuclear safety, but differences on how much international action is needed may hamper follow-up efforts, diplomats say.

Japan's crisis has prompted a rethink of energy policy around the world, underlined by Germany's decision to shut down all its reactors by 2022 and an Italian vote to ban nuclear power for decades.

Three reactors at the Japanese complex went into meltdown when power and cooling functions failed, causing radiation leakage and forcing the evacuation of some 80,000 people.

Japanese officials have come under fire for their handling of the emergency and the authorities have admitted that lax standards and poor oversight contributed to the accident.

In 2007, the IAEA was ignored when it called on Japan to create a more powerful and independent nuclear regulator, and the report underlined the need for greater regulatory control.

"An updating of regulatory requirements and guidelines should be performed reflecting the experience and data obtained during the Great East Japan Earthquake and Tsunami," it said.

Japan has a well organized emergency preparedness and response system but "complicated structures and organizations can result in delays in urgent decision making," it added.

The report also listed wider lessons for improving nuclear safety worldwide and help avert any repeat of the disaster, saying reactors should be built so that they can withstand rare and "complex combinations" of external threats.

(Editing by Mark Heinrich)

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