Homes in the direct path of the monster tornado that roared through Oklahoma City suburbs Monday were all but certain to be destroyed. Yet inexpensive construction techniques could have kept up to 85 percent of the area's damaged houses standing, according to a civil engineer.

The trick is already common along the hurricane-prone Gulf Coast — the use of clips and straps to keep the walls bolted to the roof and the foundation, explained Andrew Graettinger, a civil engineer at the University of Alabama. These parts cost about $1 each.

---

"You need several hundred of them in the house, but it is not anything drastic, it is not a humongous expense, it is relatively inexpensive," he told NBC News.

For about $2,000 more, a house can be outfitted (or retrofitted) with a safe room built to specifications of the Federal Emergency Management Agency (FEMA). These fortified rooms, often constructed with cinder blocks and filled with mortar and rebar, can withstand tornado-force winds and storm debris.

"Lower wind speeds, you design to protect your house and higher wind speeds you design to save your life," Graettinger said. "Unfortunately, you have to do them both." 

The total cost is the equivalent of installing granite countertops or a whirlpool tub, which many homeowners opt for without a second thought to make their homes look nice and raise their value. They could — and are beginning to — opt for the tornado proofing as well, Graettinger noted.

The National Weather Service initially rated Monday's storm as an EF-4, the second strongest type, with winds of 166 to 200 mph. Most — if not all — houses in its direct path were splinted to pieces.

Any storm in the top three categories, with winds at least as high as 135 mph, is strong enough to break apart wood "and at that point, a wood home is going to come apart," Graettinger said.

Even steel structures are vulnerable in those conditions, noted Curtis McCarty, a home builder in Norman, Okla., who is on the state's Uniform Building Code Commission.  

"If you are above ground and you get hit in a storm like that, no matter the type of construction unless it is a concrete-reinforced structure, you are probably not going to have anything left," he told NBC News. 

But the EF rating, Graettinger said, represents "the worst sustainable section of the storm." He and his colleagues found that during the 2011 tornadoes in Tuscaloosa, Ala., (EF-4) and Joplin, Mo., (EF-5) about 85 percent of the homes were in areas with winds ranked at or below EF-2 – 111 to 135 mph.

"All of those homes, 85 percent of the area, could have experienced much less damage," he said. 

The clips and straps recommended for tornado-proofing work by keeping the walls attached to the roof. "You are going to be able to hold the assembly of the house together better," explained McCarty. But there's nothing remotely affordable, he added, that can withstand an EF-3, EF-4, or EF-5.

Exotic materials such as carbon fiber found in bicycles and Kevlar, the material used in bulletproof vests, could be used in storm shelters to project people from devastating tornado winds, according to TechNewsDaily. The advantage is an ability to bend with the wind, reducing chances of being toppled. 

But such futuristic materials are expensive and impractical for the masses, noted Graettinger. What's exotic, he said, is that the building industry is beginning to design for tornadoes with the understanding that well-constructed homes on the fringe of even the most devastating storms can survive.

"The next step is to optimize some of these designs with more creative and exotic materials, which will come in the future," he added. "But I think we should stick with what we know works, is proven to work along the Gulf Coast … that would be a huge step forward."

John Roach is a contributing writer for NBC News. To learn more about him, visit his website.

The current boom in U.S. natural gas production from glassy shale rock formations is poised to usher in an era of energy independence and could bridge the gap between today's fossil-fuel age and a clean-energy future. But that future may be swamped in a legacy of wastewater, a new study suggests.

Natural gas production is soaring thanks to hydraulic fracturing, or fracking, a technique that shoots several million gallons of water laced with chemicals and sand deep underground to break apart chunks of the glassy rock, freeing trapped gas to escape through cracks and fissures into wells.

---

An average of 10 percent of this water flows back to the surface within a few weeks of the frack job. The rest is absorbed by the surrounding rock and mixes with briny groundwater, explained Radisav Vidic, a civil and environmental engineer at the University of Pittsburgh.

"What happens to that water is a very good question," he told NBC News. "We would like to know how much of it stays in the shale, and for how long, and is there a potential for migration away from the well."

Vidic led a review study of the scientific literature looking into these questions, which is published in Thursday's issue of the journal Science. 

He said there is a small risk that some of this water could find its way into a crack that leads up to drinking-water aquifers. Most, though, follows the path of least resistance back to the well and flows out at the rate of around 30 to 50 gallons per day. "And what comes back out is much, much worse than anything you put in there, so the real concern is, what do you do with the water that comes back out? Because that's where the potential for major environmental impact occurs," he said.

Salty wastewater
This wastewater, he noted, is 10 times saltier than seawater and contains naturally occurring radioactive material released from the shale.

For now, this wastewater is either injected into wells where, in theory, it will stay indefinitely; or it is cleaned up and reused for subsequent frack jobs. 

Recycling has become particularly common in Pennsylvania's Marcellus Shale region, where the geology limits disposal in injection wells. "I applaud the industry in Pennsylvania for coming up with that [recycling process], but it only works as long as you have more wells to inject into," Vidic said.

Eventually — and no one knows for sure when — more wastewater will be produced than there are new wells being drilled. The technology exists to treat the wastewater, but it is expensive and will leave behind mountains of salt and other solids that will need a proper home.

"The thing is, the industry is simply not addressing it right now," Vidic said. This oversight, he added, has potential be the source of panic and environmental woe when drilling slows.

The natural-gas industry downplays the issue. The concern is "a hypothetical situation that doesn't actually reflect what is really going on," Steve Everley, a spokesman for Energy-in-Depth, an industry trade group, told NBC News. 

A sudden deluge of wastewater, he noted, is "highly unlikely." But if it were to happen, he said, "companies would still be treating and finding a way to do something with the wastewater in a responsible fashion."

That wait-and-see approach worries Kate Sinding, who directs the community fracking defense project for the National Resources Defense Council, an environmental group. She pointed out that wastewater cannot be reused indefinitely.

"I think they are all counting on shipping it off somewhere else to be dealt with," she told NBC News. "In the Marcellus that would be Ohio, but not surprisingly, Ohio doesn't want all of the stuff from these other states, so we think it is a big problem and one that has to be taken much more seriously."

Frack fluid discolosures
According to Vidic, the wastewater problem is more serious than the nondisclosure of what exactly is in the fluid injected into the well, which has generated concerns about drinking water contamination. 

"There have been more than 1 million hydraulically fractured treatments done, and there is one case where we have seen the contamination of groundwater by the hydraulic fracturing fluids," he said. That one case occurred, he added, because the drilling took place in a region where there were abandoned wells, which served as conduits to the groundwater. 

He and his colleagues note that understanding the exact composition of the injection fluid is important for water quality. It's also important to find out exactly where Pennsylvania's estimated 100,000 abandoned wells are located.

The dearth of this and other data, Vidic noted, means more research is needed to fully understand the impact of natural gas development on water quality, but added that to date the scientific literature provides "no evidence of severe environmental pollution."

"This is an industry," he noted. "And any industry has a footprint … We all want cheap energy and we want more of it. So, OK, you can dig out more coal and burn coal, but I would take natural gas any day of the week over coal."

More about fracking:

• Disputes over fracking's effect cloud its future
• Agreement reached on fracking standards
• Fracking provides energy, jobs ... and quakes?

In addition to Vidic, the authors of "Impact of Shale Gas Development on Regional Water Quality" include S.L. Brantley, J.M Vandenbossche, D. Yoxtheimer, J.D. Abad.

John Roach is a contributing writer for NBC News. To learn more about him, visit his website. 

Warming oceans are pushing fish toward the poles in search of cooler waters, according to a study that raises new concerns that climate change is robbing the tropics of a primary source of income and nutrition.

Meanwhile, in higher latitudes, data show that trawlers are hauling more warm-water fish out of the ocean – a phenomenon that will change what shows up on menus at locavore restaurants from Cape Town to Tokyo. 

---

"There'll be changes in the kinds of fish that are available to people who would like to follow that kind of (eating local) strategy," Michael Fogarty, a fisheries biologist with the National Oceanic and Atmospheric Administration's Northeast Fisheries Science Center, told NBC News.

Fogarty was not involved with the new research, which he said confirms "what people have seen in different ways but usually on a more localized level." The global perspective published today in Nature, he added, put the fishing industry and consumers on alert that they'll need to adapt to climate change.

Fish as thermometers
The research used the temperature preference of fish and other marine species as a thermometer to assess the impact of climate change on the world's oceans between 1970 and 2006. Atlantic cod, for example, have a colder preferred temperature than tropical grouper.

The preferred temperature of all the species caught in a particular region, in turn, provides a snapshot of a fishery in space and time that can be tracked to see the impact of warming oceans.

"If the catch composition is having more and more warm-water species present in it, then the mean temperature of the catch will also increase," William Cheung, a fisheries biologist at the University of British Columbia, explained to NBC News.

He and his colleagues found that global fishery catches are increasingly dominated by warm-water species as a result of fish migrating out of the tropics toward the poles. For example, in British Columbia, Canada, tuna and mackerel are more abundant while sockeye salmon are declining.

Meanwhile, the tropics are losing fish. Those that remain are adapted to the warmest waters.

"If the temperatures continue to warm in the tropics, then even these hot-water adapted species will find it difficult to live in the tropics, so we would expect as a result that the fishery production potential in the tropics will decline," Cheung said.

Given that many communities in the tropics rely on fishing for income and food, this trend highlights their particular vulnerability to climate change, he added.

What to do?
"Climate change has made it to the fishmonger and onto our dining tables," Mark Payne, a marine scientist at the National Institute for Aquatic Resources in Denmark, writes in a Nature perspective article about the new study. "The question now is, how should we respond?"

According to Cheung, policymakers and fisheries managers ought to reduce existing stresses on marine ecosystems such as overfishing, habitat destruction and pollution in order to increase their resilience to climate change.

In addition, the world's fishing industry should prepare for the expected changes in species composition.

"Ultimately, it is important to reduce greenhouse gas emissions," he said. "Because if we reduce that, then we know that the rate of change in sea surface temperature will be reduced and this would actually reduce the level of response in terms of fish stocks to climate change."

John Roach is a contributing writer for NBC News. To learn more about him, visit his website. 

Sometimes, drinking a few beers after class can save the planet. A just-launched online "game" dreamed up during one such beer-drinking session aims to do that by encouraging people around the world to supply much needed data about the world's power plants that burn fossil fuels.

While the general whereabouts of these plants is known, in much of the world details are fuzzy on the kind of fuel they burn and how much electricity they produce, explained Kevin Gurney, a senior sustainability scientist at Arizona State University.

"My argument is that this is something that is actually locally known and so why not leverage that in a time in which social networks dominate our lives?" he told NBC News.

---

To do that, he and the students in his lab built Ventus, a website where anyone anywhere can enter what data they can about the world's power plants including precise location, fuel type and electricity generation. The video below explains more about the project.

The more "useful" information a person enters, the more points they earn. A winner will be announced in 2014, and will receive a trophy and become "famous among our very elite, newly-formed global group of citizen scientist enviro-nerds," the game website explains.

"I wanted to fly people to Tempe and let them golf," Gurney told NBC News. "But one of the limitations of being in a university is you can't spend money that way."

The team hopes the game will become viral enough on social media such as Facebook and Twitter to gain traction in parts of the world where power plant data is sorely lacking — which is pretty much everywhere excluding the U.S., Canada, Western Europe and South Africa.

Outside of these countries, "you pretty much fall off the cliff of information; there is very, very little," Gurney explained. 

The team did spend a few thousand dollars to purchase a comprehensive list of facilities from the Center for Global Development that provides plant names and the cities they are near. As best they could, the team plotted roughly 25,000 power plants from the list on a Google Earth map. 

While a start, the team needs more precise information to accurately model power plant carbon dioxide emissions, the source of more than 40 percent of the greenhouse gases produced by human activity.

Getting this information, however, is a challenge. Two undergraduate students in Gurney's lab spent six months poring over the list and then looking for the plants using Google Earth. They found 800. "This was just too labor-intensive and, of course, it is perfect for crowdsourcing," Gurney said.

The data collected from the game will lead to better models of carbon emissions that policymakers, in turn, can use to make more informed decisions about efforts to combat and adapt to climate change, he added. 

For all of this to happen, though, word of the game needs to spread and reach the people who can reliably provide the necessary information. The whole project could end up a failure, Gurney noted.

"That is the nature of operationalizing an idea that you had while you were sitting around having a beer with your research group."

John Roach is a contributing writer for NBC News. To learn more about him, visit his website.

About 3 million years ago, evergreen forests — not tundra — carpeted the Arctic, Greenland was green, and sea ice only formed for a few months in the winter, if it formed at all, according to analysis of sediment pulled from a Russian lake. 

"Where we are going is into this warmer world," Julie Brigham-Grette, a geologist at the University of Massachusetts Amherst, told NBC News.

At the time — the Pliocene — concentrations of the greenhouse gas carbon dioxide were around 400 parts per million, the same as they are today. But Arctic temperatures were about 14.4 degrees Fahrenheit (8 degrees Celsius) warmer than today, explained Brigham-Grette, who led the analysis.

---

Assuming the interpretation is correct — and it is consistent with other research — she added, then the models currently used to forecast future climate underrepresent the power of carbon dioxide to warm the planet.

Brigham-Grette hopes that the modeling community can tune its parameters to better match her team's data "so that we can have faith that they are doing the best job possible of making projections into the future," she said. 

Environmental storybook
The 1,043-foot-long (318-meter) sediment core is a story book of environmental change ever since a meteorite plunged into northeastern Russia some 3.6 million years ago and blasted out an 11-mile-wide (18-kilometer) crater that then filled with water.

Key to the story are bits of pollen from Douglas fir and hemlock, types of evergreen trees, that grew around Lake El'gygytgyn, about 62 miles (100 kilometers) north of the Arctic Circle. The pollen tells researchers what vegetation grew there, which in turn paints a picture of how warm and wet it was.

In the Middle Pliocene, the record suggests summer temperatures were around 59 to 61 degrees Fahrenheit (15 to 16 degrees Celsius) and annual rains of about 24 inches (60 centimeters). 

It allows a "reconstruction of the way the world was," Mark Pagani, a geologist at Yale University, who was not involved with the new research, explained to NBC News. "It is really useful; it is not a model anymore."

The analysis from this and other studies suggests that the carbon dioxide already in the atmosphere has baked several degrees of warming into the climate system, which is in the slow process of reaching a new balance. "You have to wait awhile if you want to see how warm it can get," Pagani noted.

Ancient cooling
Brigham-Grette and colleagues detail a time series from the lake sediment core in a paper published online today in Science that focuses on the transition from the warmer, wetter Arctic of the past to the beginnings of the last ice age, known as the Pleistocene. 

Earlier work indicated that glaciers started to form in the Arctic during the Pliocene, but the Lake El'gygytgyn sediment core suggests that "it is too warm in the summers to preserve the ice," Brigham-Grette said. "We don't start getting summers colder than present until about 2.5 million" years ago.

Going forward, the sediment core should allow the research community to refine its understanding of what the onset of glaciation looked like — perhaps a slow start with a scattering of small glaciers, she noted.

"That's the academic question: what drove us into glaciation," Brigham-Grette said. "The more practical one for the world today is understanding what the response time of the planet is to increasing greenhouse gases."

"And this new record from the Arctic is going to show that in fact it is quite reasonable to expect the warming we are seeing now to actually have major changes in the high latitudes."

John Roach is a contributing writer for NBC News. To learn more about him, visit his website. 

For the past ten years, skyscraper-sized icebergs have cracked off glaciers in Greenland and tumbled into the sea at an ever-quickening rate in response to global warming, raising concerns about runaway ice loss and rising seas. The good news? The rate of acceleration will slow, according to a new study.

The slowdown is related to the physics and geography that govern glacier movement, not a forecast that the rise in global temperatures will halt anytime soon. Indeed, the ice sheets will continue to melt and push up sea levels around the world, just not as quickly as feared, the study's lead author said.

---

The earlier work extrapolated the rate of acceleration seen since the late 1990s out to 2100, explained Faezeh Nick, a glaciologist at The University Center in Svalbard, Norway. But scientists now know that glaciers respond to warming in complex ways, especially those that end at the sea.

These moving tongues of ice, known as outlet glaciers, accelerate in bursts — dumping tons of ice into the ocean — but then the pace slackens. "It doesn't go lower than it was before, but it doesn't stay at the top" rate, Nick told NBC News.

Her work hinges on individual models of the four largest outlet glaciers in Greenland and their individual response to atmospheric and ocean warming. The models are based on more than a decade's worth of scientific observations.

For example, two of the glaciers are particularly sensitive to the production of surface melt water, which falls down crevasses and fractures off icebergs. Submarine melting of ice by warmer seas is big factor in another glacier, which thins the ice and releases a natural brake, allowing more icebergs to calve. 

Once the models were tuned to accurately represent the observed historic trends of these outlet glaciers, Nick used the models to forecast future ice loss using two different scenarios of warming in the coming centuries.

Under a mid-range warming of 5.04 degree Fahrenheit (2.8 degrees Celsius) by 2100, the outlet glaciers contribute 0.3 to 0.5 inches (8.5 to 13.1 millimeters) to sea level rise, which is equivalent to 30 to 47 gigatons of water per year, according to the paper published today in the journal Nature.

For perspective, Nick said that Lake Geneva, among the largest lakes in Western Europe, holds about 90 gigatons of water. "You are losing half of that lake to the ocean every year just from these four glaciers," she said.

The four glaciers account for 22 percent of Greenland's total contribution to sea level rise. If the findings are extrapolated to include iceberg production and surface melt from all of the island's glaciers, the researchers estimate a total contribution of sea level rise from Greenland of between 3 and 7 inches (65 and 183 millimeters) by 2100.

Under the warmer scenario modeled — an 8 degree Fahrenheit (4.5 degree Celsius) rise by 2100 — the team found the sea level rise would be 50 percent higher.

The modeling is "good science" and consistent with other recent findings, glaciologist Richard Alley at Pennsylvania State University, told NBC News in an email.

He explained that an icesheet can shrink by waiting for the environment to bring warmth to it or send ice off to find warmth. "Iceberg calving is the fastest way to send the ice off to melt elsewhere," he said.

The geography of the narrow fjords where the outlet glaciers terminate is such that as the glaciers retreat, friction on the glaciers will increase, thus slowing down their seaward march and, eventually, eroding their ability to dump big icebergs.

"Then, the ice must melt in place, from heat in the air, rather than melting elsewhere from water. … Note that this does not mean that we're safe because Greenland is no worry," Alley added. "Too warm, and the ice will melt, and surface melting has been accelerating overall, contributing to sea level rise."

John Roach is a contributing writer for NBC News. To learn more about him, visit his website. 

Shhh! Widespread adoption of energy-efficient technologies such as compact fluorescent light bulbs and electric cars promises to curb the pace of global climate change. But if widespread adoption is the goal, don't mention the environmental benefits, a new paper suggests.

"There is likely to be a significantly sized group that may not like these environmental messages," Dena Gromet, a researcher at the Wharton School at the University of Pennsylvania and the paper's lead author, told NBC News.

While not specifically addressed in the new paper, she added that "other messages might have more universal appeal that can be emphasized" when promoting energy efficiency such as greater energy independence and long-term financial savings.

---

Those who show a distaste for the environmental messages tend to side with conservative political ideologies, according to the paper, which teases apart how political views affect attitudes and choices when it comes to energy-efficient products.

"As expected, the more conservative participants were, the less they favored investing in energy-efficient technology," Gromet and colleagues write in the paper published online Monday in the Proceedings of the National Academy of Sciences. 

The ideological divide was strongest when energy efficiency was tied to the environmental message of reducing carbon emissions. Energy efficiency is more broadly appealing for the financial savings it offers and for increasing energy independence.

The negative impact of environmental messaging became apparent when 210 study participants were given $2 to go light bulb shopping. When energy efficient, but more costly, compact fluorescent light bulbs (CFLs) were sold with a sticker that read "Protect the Environment," conservatives shied away from them.

When the more expensive CFLs were sold without environmental messaging — but touted the fact that CFLs last 9,000 hours longer than the less expensive incandescent bulbs and reduce energy costs by 75 percent — more conservatives bought them.

When both bulbs were priced the same — 50 cents — all but one participant bought the more energy-efficient bulb, regardless of the content of the label, indicating that people across party lines give the biggest weight to economic value, the researchers note.

Environmental messages may be unnecessary to sell the energy-efficient technologies to liberals, according to the paper. These consumers may already "spontaneously" associate energy-efficient options with environmental benefits and "do not need a label to call the benefits to their attention." 

"When liberals are buying a CFL, they are already thinking about how this is a good choice because it is going to benefit the environment," Gromet explained. "Whereas our research suggests it may not be as top-of-mind for more conservative individuals."

This pattern of environmentalism and its association with the left-leaning side of the political spectrum has also been noted in survey data collected by Edward Maibach, who directs the Center for Climate Change Communication at George Mason University.

"Conservatives are as likely as liberals to take a range of energy-saving actions, such as buying fuel efficient cars and energy-efficient appliances, but they are less likely to take certain energy-saving actions that are symbolically associated with environmentalism, such as installing CFLs," he told NBC News in an email.

That said, the center's most recent survey released April 2 found that 52 percent of Republicans and Republican-leaning Independents think climate change is happening and 62 percent said America should address it.

"The most conservative Republicans, however, remain unconvinced and are not interested in seeing America respond," he said. "My guess is that it is mostly very conservative Republicans who are turned off by environmental messaging associated with energy-saving products."

John Roach is a contributing writer for NBC News. To learn more about him, visit his website.

The modern era of biology was launched 60 years ago today with the publication of a one-page paper in the journal Nature that described the DNA's double helix structure, a revelation of how organisms store biological information and pass it from one generation to the next.

The Nobel Prize winning discovery was published by the biologists James Watson, an American, and Francis Crick, an Englishman. In 2003, Congress declared that "DNA Day" was April 25.

---

The date is also special because it commemorates the completion of the Human Genome Project — the reference sequence for the 3 billion DNA letters that comprise the human genome — the instruction book for building and maintaining a human being, Francis Collins, director of the National Institutes of Health, notes in a blog post today.

To learn more about the day and the discoveries it celebrates, check out the National Human Genome Research Institute's DNA Day Facebook page. Visitors are encouraged to suggest a "DNAnalogy" that helps explain what DNA is. For example, visitor Tom Wood writes that "DNA is like an architectural blueprint. The blueprint is the plan, but it's never the final result."

The weeks leading up to this year's celebration of the 1953 discovery have been filled with stories about a 60-year-old letter in which biologist Francis Crick told his son about DNA's double helix structure. The letter and Crick's Nobel Prize sold at an auction on April 10 for a record $6 million. 

To learn more about the DNA, check out the stories below:

• New Nobel letters reveal secrets of DNA prize
• Nobel Prize medal for discovery of DNA structure to be sold
• Lessons learned as human genome map turns 10
• Human Genome Project marks 10 years

John Roach is a contributing writer for NBC News. To learn more about him, visit his website.