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Remote sensing moisture model could aid farmers

Global farmers could get better decision-making help as refinements are made to North Alabama soil moisture modeling research being done by an atmospheric science doctoral student at The University of Alabama in Huntsville (UAH).

The models indicate how much added moisture would be needed in a given area versus historical data to achieve various crop yields, and they could aid in making expensive infrastructure investments by helping to determine their economic viability.

"The important thing that I want to stress is that this is not a predictive model, it is a decision-support model. It helps farmers and officials make decisions based on historical weather patterns," says doctoral student Vikalp Mishra. In areas where water is in short supply, irrigation infrastructure can be expensive and the model could help to determine its economic cost effectiveness.

Mishra was the primary author of a paper with his advisor and UAH associate professor of atmospheric science Dr. John Mecikalski, UAH Earth System Science Center principle researcher James Cruise, and researchers from the University of Maryland-College Park and the U.S. Dept. of Agriculture's Hydrology and Remote Sensing Laboratory in Beltsville, Md.

The model uses satellite data to determine the amount of soil moisture present and then estimates yields based on available moisture. Water is at the center of nearly all farming decisions. It affects the crop cultivar, the variety of seed planted, the amount and type of fertilizer required and the amount of irrigation needed to produce a given weight of grain.

Researchers begin by using satellite derived evapotranspiration estimates at thermal infrared bands to deduce the amount of moisture being transpired by plants. Moisture data are derived from the Geostationary Operational Environmental Satellites (GOES). GOES data are inputted into the Atmosphere-Land Exchange Inverse (ALEXI) model, previously developed by Dr. Mecikalski and others. The ALEXI model calculates the evapotranspiration rates. The soil moisture is directly related to the evapotranspiration and the percentage of canopy cover so that the amount of moisture in the soil up to the rooting depth can be deduced.

"Once we have that soil moisture estimation, then the next thing is to categorize the values we obtained into surface values and root zone values," says Mishra. The amount of vegetative cover influences those values. If there is more vegetation, there is more transpiration, which means that moisture is being drawn from the soil in the root zone of the plants, he says. Less vegetative cover means the sensed moisture is evaporating at a greater rate from the top layer of soil.

Vegetation cover is estimated using the Moderate Resolution Imaging Spectroradiometer (MODIS) scientific instrument launched into Earth orbit by NASA in 1999 on board Terra (EOS AM) and in 2002 on board the Aqua (EOS PM) satellites.

"If it's more than 30 percent vegetative cover, then it is predominantly root zone moisture due to transpiration," Mishra says.

Being able to sense the strata of ground moisture to that depth is important, Mishra says, because different crops have different root depths and distributions for optimal water uptake.

Next a soil moisture profile is developed with the principle of maximum entropy model (POME), which uses prior specific data over a set of trial probabilities to determine which is the most likely outcome. The result is input into the Decision Support System for Agrotechnology Transfer (DSSAT) program, a software application program that comprises crop simulation models for over 28 crops and has been in use for more than 30 years across the world. The model encompasses all inputs into the crop, including weather, plant spacing, cultivar, fertilizer, soil type and fertility, and others.

Mishra applies as many quantified inputs about crops and weather conditions possible to this model, except one: precipitation.

At this point, he inputs his soil moisture profiles and from there he can model yields in kilograms per hectare based on how much soil moisture is available to the crop. The model can provide daily estimates of grain weights as well as water and fertilizer needs within a growing period.

Mishra's North Alabama sensor research, done in conjunction with USDA's Hydrology and Remote Sensing Laboratory, covered a 10-square-kilometer area that included dry land-farmed crops relying on rainfall only, irrigated crops, varying crop types, pasture and fallow land. The data were compared with a decade of USDA Agricultural Census yield data.

"What we found was that our soil moisture measurements and estimated crop yields were significantly comparable with county averaged National Agricultural Statistics Service yield data and ground-based precipitation-induced DSSAT results," Mishra says. His doctoral research is focused on trying to pinpoint the area of measurement more closely, reducing it from 100 square kilometers to 1 square kilometer, so the results will be more supportive of the decisions of individual farmers in an area.

The work could prove especially valuable for farmers and government officials in the more arid countries of the world, says collaborator Cruise, the principle researcher from UAH's Earth System Science Center.

"The main impetus was to run this model in areas where you don't have a lot of precipitation to start with," Cruise says. "Then you can determine just how much irrigation and other inputs you might need to get a given result." But the continuing work to pinpoint the areas of measurement could result in an online database that farmers in Alabama and elsewhere could use to help them make decisions to cope with variability in annual rainfall, he says.

"There are potentially many different gradients," Cruise says, "where the area being measured could be downsized."

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Climate change could increase thunderstorm severity, climatologist predicts

This spring may be more like a lion than a lamb. John Harrington Jr. is a synoptic climatologist and professor of geography at Kansas State University who studies weather events, how often they occur and the conditions when they occurred. He says climate change may be increasing the severity of storms.

"One of the big concerns I have is that the warmer atmospheric temperatures will drive a little bit more evaporation out of the ocean and the Gulf of Mexico," Harrington said. "One of the things that helps storms be stronger is having more moisture, so that added moisture may increase the height and severity of a tall cumulonimbus thunderstorm cloud."

Harrington said the added moisture might make storms stronger and more potent in the future.

This year may also bring a change in weather conditions due to El Ni?o, which the United States hasn’t experienced for about two years. El Ni?o warms the temperature of the Pacific Ocean, which creates cooler and wetter conditions for the West Coast. Harrington says there is a good possibility El Ni?o will arrive this fall going into winter.

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New statistical models could lead to better predictions of ocean patterns

The world's oceans cover more than 72 percent of Earth's surface, impact a major part of the carbon cycle, and contribute to variability in global climate and weather patterns. However, accurately predicting the condition of the ocean is limited by current methods. Now, researchers at the University of Missouri have applied complex statistical models to increase the accuracy of ocean forecasting that can influence the ways in which forecasters predict long-range events such as El Nino and the lower levels of the ocean food chain -- one of the world's largest ecosystems.

"The ocean really is the most important part of the world's environmental system because of its potential to store carbon and heat, but also because of its ability to influence major atmospheric weather events such as droughts, hurricanes and tornados," said Chris Wikle, professor of statistics in the MU College of Arts and Science. "At the same time, it is essential in producing a food chain that is a critical part of the world's fisheries."

The vastness of the world's oceans makes predicting its changes a daunting task for oceanographers and climate scientists. Scientists must use direct observations from a limited network of ocean buoys and ships combined with satellite images of various qualities to create physical and biological models of the ocean. Wikle and Ralph Milliff, a senior research associate at the University of Colorado, adopted a statistical "Bayesian hierarchical model" that allows them to combine various sources of information as well as previous scientific knowledge. Their method helped improve the prediction of sea surface temperature extremes and wind fields over the ocean, which impact important features such as the frequency of tornadoes in tornado alley and the distribution of plankton in coastal regions -- a critical first stage of the ocean food chain.

"Nate Silver of The New York Times combined various sources of information to understand and better predict the uncertainty associated with elections," Wikle said. "So much like that, we developed more sophisticated statistical methods to combine various sources of data -- satellite images, data from ocean buoys and ships, and scientific experience -- to better understand the atmosphere over the ocean and the ocean itself. This led to models that help to better predict the state of the Mediterranean Sea, and the long-lead time prediction of El Nino and La Nina. Missouri, like most of the world, is affected by El Nino and La Nina (through droughts, floods and tornadoes) and the lowest levels of the food chain affect us all through its effect on Marine fisheries."

El Nino is a band of warm ocean water temperatures that periodically develops off the western coast of South America and can cause climatic changes across the Pacific Ocean and the U.S. La Nina is the counterpart that also affects atmospheric changes throughout the country. Wikle and his fellow researchers feel that, through better statistical methods and models currently in development, a greater understanding of these phenomena and their associated impacts will help forecasters better predict potentially catastrophic events, which will likely be increasingly important as our climate changes.

Wikle's study, "Uncertainty management in coupled physical-biological lower trophic level ocean ecosystem models," was funded in part by the National Science Foundation and was published in Oceanography and Statistical Science.

Cite This Page:

University of Missouri-Columbia. "New statistical models could lead to better predictions of ocean patterns." ScienceDaily. ScienceDaily, 18 March 2014. .University of Missouri-Columbia. (2014, March 18). New statistical models could lead to better predictions of ocean patterns. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2014/03/140318154927.htmUniversity of Missouri-Columbia. "New statistical models could lead to better predictions of ocean patterns." ScienceDaily. www.sciencedaily.com/releases/2014/03/140318154927.htm (accessed April 19, 2014).

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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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Winds could fan deadly Calif. wildfire

Frank Bellino, The Press-Enterprise/AP

Residents help battle the fire in Murrieta, Calif. Firefighters say it's too soon to determine the gender of the body found in a burned home in the Campo area on Monday.

Frank Bellino, The Press-Enterprise/AP

Residents help battle the fire in Murrieta, Calif. Firefighters say it's too soon to determine the gender of the body found in a burned home in the Campo area on Monday.

CAMPO, Calif. (AP) â?? A fire that killed an elderly man who refused to evacuate and burned 20 homes in rural San Diego County was smoldering Tuesday, but gusty afternoon winds could push it back to life, authorities said.

Nearly 1,000 firefighters planned an all-out effort to surround the blaze, which continued to threaten about 25 homes in the rural community of Tierra del Sol near the U.S.-Mexican border, said fire spokesman Andy Menshek. Residents of two other small communities were allowed to return home earlier.

About 80 residents remained under evacuation orders.

"That is the one remaining evacuated area," Menshek said. "That's out highest priority today â?¦ we have propane tanks, downed power lines and a lot of hotspots to mop up."

The fire, which has burned nearly 4 1/2 square miles of hilly brush land since Sunday, was 55 percent contained.

Although no active flame was showing, winds began picking up Tuesday morning and gusts of up to 40 mph could hit in the afternoon, Menshek said.

"If we get one ember over the line, the fire could take off," he said.

On Monday, the body of an elderly man was retrieved from a burned home in Tierra del Sol. Neighbors reported the man missing when they saw his only vehicle parked at the home, authorities said. His identity was not immediately released, but neighbors told U-T San Diego he was 82 and had one leg.

Reverse 911 calls notifying homeowners of the evacuation order were made by the county sheriff's department. Neighbors said the man decided to remain.

"He felt that he was going to be OK if he stayed," sheriff's Lt. Rose Kurupas told the newspaper.

"He chose to stay and that's sad," Menshek said. "That's why we issue these evacuations."

Other blazes in the West remained active, blanketing some communities in eastern Washington state with smoke. The air quality in many Wenatchee and Cashmere areas was deemed either "hazardous" or "unhealthy" by state officials.

Authorities there updated the sizes of two of the state's largest fires after more accurate mapping and burnouts to create fire lines, officials said. The Wenatchee complex of fires was reported at 82 square miles, while the Table Mountain fire had burned nearly 57 square miles.

Crews also gained ground on a 5 1/2-square-mile fire in Montana's Musselshell County, allowing residents to return to about 50 homes southeast of Roundup. That blaze was human-caused and under investigation.

Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.For more information about reprints & permissions, visit our FAQ's. To report corrections and clarifications, contact Standards Editor Brent Jones. For publication consideration in the newspaper, send comments to letters@usatoday.com. Include name, phone number, city and state for verification. To view our corrections, go to corrections.usatoday.com.

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Winds could fan deadly Calif. wildfire

Frank Bellino, The Press-Enterprise/AP

Residents help battle the fire in Murrieta, Calif. Firefighters say it's too soon to determine the gender of the body found in a burned home in the Campo area on Monday.

Frank Bellino, The Press-Enterprise/AP

Residents help battle the fire in Murrieta, Calif. Firefighters say it's too soon to determine the gender of the body found in a burned home in the Campo area on Monday.

About 80 residents remained under evacuation orders.

"That is the one remaining evacuated area," Menshek said. "That's out highest priority today â?¦ we have propane tanks, downed power lines and a lot of hotspots to mop up."

The fire, which has burned nearly 4 1/2 square miles of hilly brush land since Sunday, was 55 percent contained.

Although no active flame was showing, winds began picking up Tuesday morning and gusts of up to 40 mph could hit in the afternoon, Menshek said.

"If we get one ember over the line, the fire could take off," he said.

Reverse 911 calls notifying homeowners of the evacuation order were made by the county sheriff's department. Neighbors said the man decided to remain.

"He felt that he was going to be OK if he stayed," sheriff's Lt. Rose Kurupas told the newspaper.

"He chose to stay and that's sad," Menshek said. "That's why we issue these evacuations."

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'Daughter of Isaac' could hit Gulf Coast

It could be stormy deja vu all over again for the Gulf Coast this weekend, as remnants of Hurricane Isaac meander in the Gulf of Mexico just off Pensacola, Fla.

This area of disturbed weather "could become a tropical depression as early as Thursday, though Friday is more likely," says Weather Underground meteorologist Jeff Masters. He adds that the storm would probably make landfall along the Florida Panhandle or west coast of Florida on Sunday.

If the disturbance reaches the 39-mph threshold to become a named storm, the "daughter of Isaac" would be called Nadine.

Regardless of whether it becomes a named storm, bad weather is likely along the Gulf Coast for the next several days.

"Very humid air, combined with the disturbance, will unleash downpours and the potential for flash flooding from part of the Louisiana coast to the Florida Panhandle," reports AccuWeather meteorologist Alex Sosnowski.

Elsewhere in the tropics, Hurricane Leslie became the sixth hurricane of the season far out in the Atlantic Ocean on Wednesday afternoon, and could hit Bermuda over the weekend and eastern Canada next week, the National Hurricane Center reported. As of 5 p.m. Wednesday, Leslie had sustained winds of 75 mph, and was crawling to the north at 2 mph. The hurricane was 460 miles south southeast of Bermuda.

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While Midwest and East bake, Northwest could see some flakes

The unofficial start to summer will kick off with blazing heat across most of the eastern half of the country this Memorial Day weekend.

By Laurie Skrivan, AP

Lifeguard Sam McCabe of cleans off the water slide at an aquatic center in Maplewood, Mo., on Thursday in preparation for the Memorial Day holiday weekend. Residents across the Midwest and East might be dealing with record-setting heat during the holiday weekend.

By Laurie Skrivan, AP

Temperatures will soar into the 90s as far north as Illinois. Chicago could hit 100 degrees on Sunday.

Elsewhere, a pesky, windy storm could ruin beach plans along the Southeast coast, while parts of the Northwest deal with light snow and chilly weather.

July in May: Hot and humid conditions will be the rule in the southern Plains, Mississippi Valley, Great Lakes, Ohio Valley, the Mid-Atlantic and the Southeast all three days of this holiday weekend. High temperatures in the 90s will be widespread from Texas to Maryland.

Cities such as Memphis, Louisville, Little Rock and St. Louis could all break temperature records. The Indianapolis 500 could be run in record heat on Sunday.

The worst of the heat isn't expected to make it into the Northeast and New England, however, where temperatures in the 70s and 80s are likely.

Soggy Southeast: Just like last weekend's Tropical Storm Alberto, another slow-moving storm will meander around the Southeast coast this weekend, potentially bringing bands of rain, gusty winds and rough surf. The storm may become tropical, and it would receive the name Beryl.

Other than the ruined outdoor plans, the rain will be welcome across the drought-plagued states of Florida, Georgia, and the Carolinas.

Wintry West, severe North: Some parts of the northern Rockies and Northwest will be in the 40s and 50s this weekend. Some snow is possible at higher elevations.

Severe storms could rattle the upper Midwest through the weekend as cooler air clashes with the unusual heat.

For more information about reprints & permissions, visit our FAQ's. To report corrections and clarifications, contact Standards Editor Brent Jones. For publication consideration in the newspaper, send comments to letters@usatoday.com. Include name, phone number, city and state for verification. To view our corrections, go to corrections.usatoday.com.

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'Monster' sunspot could hurl flares at Earth

A "monster sunspot" more than 60,000 miles wide could send some powerful solar flares toward Earth on Wednesday, NASA says.

The sunspot -- actually a group of four spots, each larger than Earth, and smaller spots -- emerged over the weekend and was spotted by the orbiting Solar Dynamics Observatory and amateur astronomers, Spaceweather.com reported (via Space.com). It tossed off a moderately strong M-class flare today, and is expected to follow up with even stronger flares, possibly even X class.

Sunspot AR 1476 is so big that a photographer in the Philippines captured it at sunset, without a solar telescope.

But Spaceweather offers potential sungazers this crucial warning:

Even when the sun is dimmed by clouds and haze, looking into the glare can damage your eyes. Looking through unfiltered optics is even worse. If you chose to photograph the low sun, use the camera's LCD screen for viewfinding.

Sunspots don't excite you? How about a pair of coronal mass ejections, or a dark, coronal hole that has opened in the sun's atmosphere and is hurling solar winds toward us? Good chance of strong geomagnetic activity, including auroras.

Want to know the space weather now? NOAA has it.

The latest sun show comes three weeks after the spectacular eruption captured by the solar orbiter.

BLOG: Satellite captures giant eruption from sun today

NASA has a primer on the solar cycle.

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Weather pattern could fuel more Ala. tornadoes

HUNTSVILLE, Ala. (AP) – This isn't a tornado warning, nor is the siren about to go screaming across the Tennessee Valley.

Dusty Compton, AP

A tornado roars through Tuscaloosa, Ala., in April 2011.

Dusty Compton, AP

A tornado roars through Tuscaloosa, Ala., in April 2011.

But the potential and the indicators are in place to make the upcoming spring tornado season a rocky one to ride out.

This follows a storm season in 2011 that saw several killer tornadoes lash Alabama.

John Christy, the state climatologist and director of the Earth System Science Center at the University of Alabama in Huntsville, cited the presence of the La Niña weather pattern as a cause for tornado apprehension this spring.

"In a La Niña type year, we tend to have more of these types of experiences with the trailing cold front creating the opportunity for those specific ingredients to provide the high contrast between cold and warm," Christy said.

"We are still in La Niña pattern. The long-range forecast for the spring is for warmer than usual. So that sets up an opportunity for a contrast along the way for these ingredients to come together."

If it happens, Kevin Knupp will be ready. A professor of atmospheric sciences at UAH who studies tornadoes, Knupp is working on research about the influence gravity waves have on tornadoes.

Knupp compared the gravity waves to the way water moves across a lake. As the gravity waves encounter a potential tornado, it can enhance the likelihood of a twister developing, according to Knupp's theory.

"When the waves intersect the storm, oftentimes - not always but most of the time - there is a response from the storm," Knupp said. "If there is an existing circulation, it intensifies that existing circulation there and if there is no tornado genesis, the formation of a tornado can occur at that time."

Watching gravity waves -- which is easier in a humid climate like Alabama -- can aid forecasters in identifying tornadoes. Knupp said the National Weather Service in Huntsville was already using gravity waves among its tools for distinguishing tornadoes.

"We can be more specific on when and where it might form," said Knupp, who is also studying the impact topography has on the intensity of tornadoes. "We want to do that because the false alarm rate on tornado warnings has been so high in this area."

So what's on the horizon for the Tennessee Valley as prime tornado season approaches in March and April?

"From a historical standpoint, Alabama gets about 60 tornadoes a year," Christy said. "Most of them come in the spring. So by any standard measure, you should be ready for something to happen this spring.

"With the way the global atmosphere circulation is set up (with the La Niña pattern), there is a bit more chance that number will be higher than average this spring."

The La Niña pattern, Christy and Knupp said, brings cold air from the Pacific Ocean into close proximity with warm air from the Gulf of Mexico. Christy described it as an "opportunity" for the two air masses to "collide" over Alabama and that's when the atmosphere becomes unstable.

But Christy downplayed any seeming increase in tornadoes in recent years.

"We still have just as many tornadoes as we've ever had," he said. "We just put more stuff in their way to hit. So the damage from tornadoes will just continue to rise."

Of course, weather experts are loathe to look farther into the future than absolutely necessary. But history, in a sense, can be a crystal ball with a peek at what's to come.

"If it happened before, it'll happen again and probably worse," Christy said. "That's my general rule of climate."

Said Knupp, "I remember that word for word and that's what I tell my students."

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Climate change could increase storm surges

Last year's most devastating tropical system -- Hurricane Irene -- was considered by some experts to be a "100-year-event," a storm that comes around only once a century.

Irene lashed the East Coast in August, killing at least 45 people and leading to $7.6 billion in damages.

But a study out this week in Nature Climate Change says that due to global warming, these monster storms could make landfall more frequently, causing destructive storm surges every 3 to 20 years instead of once a century.

The lead author of the study was Ning Lin of the Massachusetts Institute of Technology, who partnered with scientists at Princeton University to undertake the research.

Lin and her colleagues used computer models to simulate future hurricanes, looking at the impact of climate change on storm surges, with New York City as a case study. The team simulated tens of thousands of storms under different climate conditions.

Today, a "100-year storm" has a surge flood of about two meters, on average, in New York City. But with added greenhouse gas emissions due to the burning of fossil fuels, the computer models found that a two-meter surge flood would instead occur once every three to 20 years.

Lin says that knowing the frequency of storm surges may help urban and coastal planners design seawalls and other protective structures.

While the number of hurricanes globally may or may not increase due to global warming, some scientists say that the ones that do form could be more intense than they would be otherwise.

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New Forecast: Sun's 'Superstorms' Could Doom Satellites (SPACE.com)

Magnetic storms set off by the sun could pose a bigger threat than thought to weather, communication, military and other satellites close to Earth, with a potentially devastating economic impact, scientists suggest.

In the new study, researchers found that solar radiation can energize a belt of high-energy particles that surrounds Earth more dramatically than previously believed.

The study focused on the possible effects of a particularly strong magnetic storm on the Van Allen radiation belts, the dangerous rings of high-energy particles that girdle the Earth. The belts are split into two distinct zones. The outer belt, which is made up of electrons, reaches from about 15,800 to 31,600 miles (25,500 to 51,000 kilometers) above the surface, while the inner belt, which consists of a mix of electrons and protons, reaches from about 4,000 to 8,000 miles (6,400 to 12,800 km) above. [Stunning Photos of Solar Flares & Sun Storms]

Scientists had known the outer belt could become far more intense during geomagnetic storms caused by high-energy particles spewed by the sun, such as the storm that supercharged Earth's northern lights display Monday night (Sept. 26). However, they have long thought such storms do not affect the inner belt.

Now computer simulations suggest that during a "superstorm" — which has occurred in the past and is likely to recur in the future ? the electrons in the inner belt, too, could become energized. Near-Earth radiation could then remain dramatically more intense for several years afterward.

"The increase in radiation in the inner zone may last for up to a decade and continue damaging satellites for years after a very strong storm," study lead author Yuri Shprits, a space physicist at the University of California, Los Angeles, told SPACE.com.

This radiation would damage satellites in that zone and potentially cut their lifetimes by five-sixths or more. [Related: Space Radiation to Rise for Astronauts, Airline Passengers]

"It would not destroy all satellites at once," Shprits said. "However, at least according to our calculations, a very strong storm can increase the radiation dose in the inner zone by a factor of 10, and within a few years we may lose a significant portion of the satellites that traverse the inner zone."

In terms of new strategies that might be needed to protect satellite systems, "it's hard to say," Shprits said. "First of all, we need to estimate risks and estimate cost. If cost is too high, we may want to accept the risks and start getting ready to replenish the fleet in the case of such event."

"There are a number of rather expensive strategies that can be used to mitigate the risk, including redundancy in electronics and increased shielding," he added. "Zero risk means infinite cost."

Two missions to study the radiation belts are planned for 2012, Shprits noted: NASA's Radiation Belt Storm Probe will observe radiation belts in the equatorial plane, while Moscow State University's LOMONOSOV mission, with UCLA-built instruments on board, will observe radiation belts at low altitudes.

The scientists detailed their findings online in the Aug. 25 issue of the journal Space Weather.

Follow SPACE.com contributor Charles Q. Choi on Twitter @cqchoi. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

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Pakistan warns floods could affect millions (AFP)

ISLAMABAD (AFP) – Pakistan warned on Wednesday that floods triggered by monsoon rains could affect millions more people this year, but claimed it was better prepared after a massive humanitarian crisis in 2010.

Last year, monsoon-triggered floods affected up to 21 million people and killed an estimated 1,750 people, causing an estimated $10 billion in losses and hammering the already depressed economy.

"There is a very little chance of flooding at the scale of last year and not more than two million people are likely to be affected by floods this year," said Zafar Qadir, the head of the national disaster management authority.

Last year's floods were the worst in Pakistani history.

"Even if there is flooding like last year, not more than six million people will be affected and we are prepared for that," Qadir said.

Qadir said normal annual rain fall in Pakistan is 137.5 millimetres and that this year a 10 percent decline is forecast, except in northern regions where a 10 percent increase is likely.

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More rain could worsen flooding along Missouri River (Reuters)

MISSOURI VALLEY, Iowa (Reuters) – Unwelcome waves of thunderstorms dumped rain and hail in eastern Nebraska and western Iowa on Thursday and heavy rain fell in Montana this week that could make historic Missouri River flooding worse.

At Omaha, Nebraska, the Missouri River reached 30.4 feet overnight, the second highest level behind the historic 1952 flood, and federal officials said a levee near Hamburg, Iowa, sustained a third partial breach on Thursday morning.

Iowa officials said they were preparing to close parts of Interstate 29 from Sioux City to Council Bluffs by late Friday, including a section that runs by Missouri Valley, Iowa.

"Nobody knows how much we'll get," said Jeff Ellis, owner of several gas stations/convenience stores in Missouri Valley, Iowa, and across the river in Blair, Nebraska, of the flooding. "Two feet, zero feet, nobody knows. It's all a guess."

Slow moving storms dumped rain across Missouri Valley on Thursday afternoon, causing street flooding along U.S. Highway 30, which runs east-west through town. At an Ellis station, 15 people soaked to the skin heaved hundreds of sandbags.

"I grabbed a bunch of college kids and high school guys from Blair, good guys," Ellis said, shaking his head as rain poured down. "We're going to sandbag the front and the side."

Rain is forecast for six of the next seven days in the area around Omaha, but more across the river in Iowa.

"I'm sure to those who are monitoring how much water is being stored and released from reservoirs ... I'm sure any rainfall would be considered a concern to them," said Jim Meyer, meteorologist in charge for the National Weather Service in the Omaha area.

Meyer said a lot of the precipitation has already been factored into forecasts given to federal officials.

On Wednesday, the U.S. Army Corps of Engineers added to planned water releases from the Fort Peck Dam in Montana for a second consecutive day due to hard rains.

About 260 miles of the Missouri have been closed to boaters from Gavins Point Dam south to where the borders of Iowa, Nebraska and Missouri meet. That is near where sandbags were dropped by helicopter to patch a partial levee breach Sunday that threatens the town of Hamburg, Iowa.

The Corps does not expect the levee repairs to withstand the full weight of the Missouri and contractors are racing to raise a secondary levee to protect Hamburg by June 14, when peak water releases are planned from Gavins Point.

HEAVY MONTANA RAINS

From Montana through Missouri residents have been shoring up levees along the Missouri River ahead of planned record water releases from its six major dams to relieve pressure on reservoirs swollen by heavy rains and melting snow.

Volunteers were placing sandbags around a Warren Distribution facility in Council Bluffs on Thursday across the Missouri River from Omaha.

The river has six dams from Fort Peck in Montana to Gavins Point on the South Dakota-Nebraska border. It runs freely below Gavins Point the more than 800 miles to the Mississippi River, making that dam a focus for people along the Lower Missouri.

All of the dams are planned to reach maximum release rates by about mid June and hold them through at least mid August.

Up to five inches of rain fell in parts of Montana from Monday through Wednesday, forcing the Corps to increase planned releases to 60,000 cubic feet per second at Fort Peck and warn that the rate could be increased from there.

The Montana rains forced fresh evacuations due to overflows on tributaries, including in Nashua downstream of Fort Peck, and in flood-battered Roundup on the Musselshell River.

The Corps said the Garrison Dam reservoir above Bismarck, North Dakota, had capacity to handle the additional releases from Fort Peck and has left intact its planned maximum releases at 150,000 cubic feet per second from the other five dams.

The Missouri River forms the northwest portion of the Mississippi River basin that stretches from Montana to western New York and funnels water south into the Gulf of Mexico.

Thousands of South Dakota and North Dakota residents have voluntarily left homes in communities protected by hastily built sandbag barriers and levees ahead of peak releases.

On Thursday, officials cautioned that the sustained record flows could still threaten levees in the Dakotas now holding.

Corps officials also have warned that more breaches like the one near Hamburg are likely given the varying strengths of the flood protections and the height, speed and duration of planned releases of water from reservoirs.

(Additional reporting by David Bailey in Minneapolis, James Kelleher in Chicago and Laura Zuckerman in Salmon, Idaho; Editing by Greg McCune and Jerry Norton)

(Corrects paragraph 14 to reflect that Warren Distribution was conducting sandbag operation, not Ameristar Casino)