Statistics research could build consensus around climate forecasts

Huge levels of data associated with global warming are now being put together by research groups around the globe. Data from all of these numerous sources leads to di?erent climate forecasts hence, the necessity arises to mix information across data sets to reach a consensus regarding future climate estimations.

Inside a paper released last December within the SIAM Journal on Uncertainty Quantification, authors Matthew Heaton, Tamara Greasby, and Stephan Sain propose a record hierarchical Bayesian model that consolidates global warming information from observation-based data sets and climate models.

"The huge variety of climate data -- from reconstructions of historic temps and modern observational temperature dimensions to climate model forecasts of future climate -- appears to agree that global temps are altering," states author Matthew Heaton. "Where these data sources disagree, however, is as simple as just how much temps have transformed and therefore are likely to change later on. Our research seeks to mix a variety of causes of climate data, inside a statistically rigorous way, to find out a consensus how much temps are altering."

Utilizing a hierarchical model, the authors mix information from all of these various sources to acquire an ensemble estimate of current and future climate together with an connected way of measuring uncertainty. "Each climate databases gives us approximately just how much temps are altering. But, each databases also offers a diploma of uncertainty in the climate projection," states Heaton. "Record modeling is really a tool not only to obtain a consensus estimate of temperature change but additionally approximately our uncertainty relating to this temperature change."

The approach suggested within the paper combines information from observation-based data, general circulation models (GCMs) and regional climate models (RCMs).

Observation-based data sets, which focus mainly on local and regional climate, are acquired if you take raw climate dimensions from weather stations and using it to some power grid defined within the globe. This enables the ultimate data product to supply an aggregate way of measuring climate instead of being limited to individual weather data sets. Such data sets are limited to current and historic periods of time. Another supply of information associated with observation-based data sets are reanalysis data takes hold which statistical model predictions and weather station findings are combined right into a single gridded renovation of climate within the globe.

GCMs are computer models which capture physical processes regulating the climate and oceans to simulate the response of temperature, precipitation, along with other meteorological variables in various situations. While a GCM portrayal of temperature wouldn't be accurate to some given day, these models give fairly good estimations for lengthy-term average temps, for example 30-year periods, which carefully match observed data. A large benefit of GCMs over observed and reanalyzed information is that GCMs can simulate climate systems later on.

RCMs are utilized to simulate climate on the specific region, instead of global simulations produced by GCMs. Since climate inside a specific region is impacted by the relaxation of Earth, atmospheric conditions for example temperature and moisture in the region's boundary are believed by utilizing other sources for example GCMs or reanalysis data.

By mixing information from multiple observation-based data sets, GCMs and RCMs, the model acquires a quote and way of measuring uncertainty for that climate, temporal trend, along with the variability of periodic average temps. The model was utilized to evaluate average summer time and winter temps for that Off-shore Southwest, Prairie and North Atlantic regions (observed in the look above) -- regions that represent three distinct environments. The idea is climate models would behave in a different way for all these regions. Data from each region was considered individually to ensure that the model might be fit to every region individually.

"Our knowledge of just how much temps are altering is reflected in most the information open to us," states Heaton. "For instance, one databases might claim that temps are growing by 2 levels Celsius while another source indicates temps are growing by 4 levels. So, will we believe a couple-degree increase or perhaps a 4-degree increase? The reply is most likely 'neither' because mixing data sources together indicates that increases would probably be approximately 2 and 4 levels. The thing is that that not one databases has all of the solutions. And, only by mixing a variety of causes of climate data shall we be really in a position to evaluate just how much we believe temps are altering."

Some previous such work concentrates on mean or average values, the authors within this paper acknowledge that climate within the larger sense includes versions between years, trends, earnings and extreme occasions. Therefore, the hierarchical Bayesian model used here concurrently views the typical, linear trend and interannual variability (variation between years). Many previous models also assume independence between climate models, whereas this paper makes up about parallels shared by various models -- for example physical equations or fluid dynamics -- and fits between data sets.

"While our work is a great initial step in mixing a variety of causes of climate information, we still are unsuccessful for the reason that we still omit many viable causes of climate information," states Heaton. "In addition, our work concentrates on increases/decreases in temps, but similar analyses are necessary to estimate consensus alterations in other meteorological variables for example precipitation. Finally, hopefully to grow our analysis from regional temps (say, over just part of the U.S.) to global temps."

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Microwave radar monitors sliding slopes: Geodesists research within the Alps

The "Steinlehnen" slope in Northern Tyrol (Austria) began to maneuver in 2003. Rockfalls threatened people, roads and structures. Meanwhile, peace has came back even though the slope is basically "sneaking," Steinlehnen is becoming a fascinating research object for researchers recently.

Professor Andreas Eichhorn from the Geodetic Measurement Systems and Sensors branch within the Department of Civil and Environment Engineering in the Technical College of Darmstadt started the interdisciplinary project KASIP (Understanding-based Security Alarm with Recognized Deformation Predictor) along with the Technical College of Vienna and also the "alpS" research institute the aim ended up being to mix metrological findings from the slope with computer models.

"An incline is greatly complex," states Eichhorn. It can be hard to find out just how a mountain slope consists and just how failing mechanism works at length. Therefore, researchers won't have the ability to depend exclusively on computer-based models to calculate mass actions later on additionally they need efficient and precise surveillance and monitoring systems which are as comprehensive as you possibly can.

To get this done, Eichhorn and the team examined different techniques at Steinlehnen. "Setting up sensors in highly active regions of the mountain is extremely harmful," describes Eichhorn. "I was searching for a technique that, amongst other things, makes non-contact observation possible." Ultimately, one way demonstrated to become particularly appropriate although its fundamental physical principle has been utilized in geodesy for any very long time, it had been not used at all for that monitoring of slopes. This process utilizes a microwave radar from the Department of Physical Geodesy and Satellite Geodesy from the TU Darmstadt (Professor Matthias Becker), that was applied prototypically by Eichhorn's team of Darmstadt researchers.

Here, the whole the surface of an incline is "shot" with microwaves which are deflected in the surface and may then be examined. By evaluating different dimensions, the researchers can document changes of only a couple of millimeters. Accumulations or erosion of rock material, or perhaps the start of a significant landslide, can thus be recorded, Eichhorn states. As opposed to techniques that scan the top with laser light, for instance, microwaves deliver a smaller amount disturbance. "A laser has an excessive amount of noise," states Eichhorn. In her own dissertation, doctorate candidate Sabine R?delsperger developed an assessment technique for interpretation the measured data amongst other things, this causes it to be easy to remove meteorological disturbances and to reach significant three dimensional pictures of the slope.

Throughout the KASIP experiments, the geodesists from Darmstadt, along with their co-workers in the area of geophysics, accomplished many important experience for that better interpretation of observed geophysical phenomena and also the correlation between your weather and also the sliding behavior from the slope. However the research also offers practical benefits, as Eichhorn describes: "Exclusively when it comes to technology, you'll be able to continuously monitor a sizable-scale critical slope in high-resolution. Accelerations -- early indications from the possible sliding of huge public -- could be detected, also it can be determined once the slope stops moving."

Microwave radar products continue to be very costly, however the method already has potential like a good early warning system: "Should you observe critical slopes together, you can dependably determine wherever something is going on,Inch states Eichhorn. "Then less costly measurement systems as well as their sensors might be particularly applied there."

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'Standing on a comet': Rosetta mission will contribute to space weather research

A comet-bound spacecraft that's been in sleep mode for more than two years is scheduled to wake up on the morning of Jan. 20 -- beginning the home stretch of its decade-long journey to a mile-wide ball of rock, dust and ice.

If all goes as planned, Rosetta -- a European Space Agency-led mission that involves University of Michigan engineers and scientists -- will be the first craft to actually land on a comet as well as track it for an extended period of time.

The Philae lander will latch on to the core of comet 67P/Churyumov-Gerasimenko in November and the orbiter will operate until the end of 2015. No mission has ever attempted such an in-depth look at one of these relics of the earliest days of our solar system.

Engineers at U-M's Space Physics Research Lab built electronic components for an onboard instrument that's believed to be the most sensitive of its kind ever flown in space. And a team of researchers will be involved in the mission science as well.

While most of the big questions Rosetta aims to answer deal with the origin and evolution of the solar system, U-M scientists will make a unique contribution that could provide very practical insights into how the sun and planets interface today.

They'll analyze measurements taken at the comet to study solar wind interactions that can lead to solar storms. The solar wind is a stream of charged particles emanating from the sun. Solar storms are bursts of activity that can threaten astronauts and damage Earth's satellites and electric grid.

"How the solar wind operates is one of the biggest outstanding questions about the solar system today. By studying how it interacts with cometary gases, we can learn a lot about the composition of the solar wind," said Tamas Gombosi, the Rollin M. Gerstacker Professor of Engineering in the Department of Atmospheric, Oceanic and Space Sciences.

Gombosi and his research group are leaders in the field of space weather. A model they developed was recently adopted by the national Space Weather Prediction Center.

At the sun's equator, the wind travels rather slowly, Gombosi said. It moves faster at high latitudes. Interactions between the two varieties can lead to magnetospheric storms. Earth orbits near the equator, so it's hard to study the fast wind from our vantage point.

"But comets pass through all of it. With their help, we can study the fast solar wind," Gombosi said.

Gombosi and other U-M researchers will be involved in additional Rosetta goals. They'll study and simulate how quickly the comet outgases material from its nucleus to its tail as it rings around the sun. They'll be involved in examining what elements are in the comet's tail, atmosphere and ionosphere, as well as how fast the electrified particles in the ionosphere are traveling.

Michael Combi, the Freeman Devold Miller Collegiate Research Professor in the Department of Atmospheric, Oceanic and Space Sciences, is a co-investigator on several instruments. He'll look into the rate at which the comet's core is sublimating, or turning from a solid into a gas, and he'll also work on a team that's analyzing those gases. They'll explore the levels of carbon monoxide and carbon dioxide, for example. They can't detect carbon dioxide from Earth.

"It's very difficult to observe some of the chemical species when they're far away and faint. Carbon dioxide is probably the second most abundant species at most comets, but it's not been observed in the thousands we've looked at from Earth," said Combi, who has studied comets for more than 30 years.

Comets -- small rock and ice bodies -- were present in the nebula that spawned the solar system and have been orbiting ever since in far away, cold belts either just past the orbit of Neptune or a quarter of the distance to the nearest star. For scientists, they're archeological artifacts that help them understand how the solar system formed and evolved. They're believed to have delivered Earth's oceans and perhaps the seeds of life in organic materials.

"People use the analogy that it's been in the freezer for the past 4.5 million years and brought in for convenient study. So we're looking as much as we can at the way the way the solar system was 4.5 billion years ago," Combi said.

Comet 67P/Churyumov-Gerasimenko is one of the smallest bodies humans have ever tried to land on. Its gravity is about 1,000 times less than that of Earth.

"On the lander, there's a camera that can look straight down like you're standing up and looking at the ground. Then there's a panoramic camera that can look out and see a picture of the horizon. It'll be fun to see what this landscape looks like," Combi said. "It'll be like standing on a comet."

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Research reveals bottom feeding techniques of tagged humpback whales in Stellwagen Bank National Marine Sanctuary

Contact: Vernon Smith, 301-713-7248
Anne Smrcina, 781-545-8026 x204 Research reveals bottom feeding techniques of tagged humpback whales in Stellwagen Bank National Marine Sanctuary

New NOAA-led research on tagged humpback whales in Stellwagen Bank National Marine Sanctuary reveals a variety of previously unknown feeding techniques along the seafloor. Rather than a single bottom feeding behavior, the whales show three distinct feeding approaches: simple side-rolls, side-roll inversions, and repetitive scooping.

A recently published paper, in the journal Marine Mammal Science, indicates that bottom side-roll techniques are common in Stellwagen Bank National Marine Sanctuary and the Great South Channel study area, a deep-water passage between Nantucket, Mass. and Georges Bank-further southeast.

The study further states that the observed feeding behavior also leads to vulnerability to entanglement in bottom set fishing gear, an issue which is a major mortality factor for the species. This finding reaffirms a NOAA Fisheries regulation that mandates the use of sinking line between fishing traps used in the lobster fishery as a way of reducing entanglements.

The new findings follow earlier NOAA-led studies detailing so-called "bubble net" feeding behaviors near and at the surface. Bubble net feeding is a behavior in which humpback whales corral and contain fish into a small area by trapping them in nets of air bubbles so they can more efficiently scoop them up in their large filter-feeding mouths.The behaviors are used by individual animals and as part of coordinated feeding behaviors involving two or more animals.

"Tagging technology is allowing us to observe whales underwater, much as land-based biologists study animal subjects in their specific environments," said David Wiley, sanctuary research coordinator and a co-author on the paper. "The data have allowed us to detect new feeding techniques as well as nuances in those behaviors. We have determined that bottom feeding is a much more commonly used technique than the more well known bubble net behaviors."

Bottom side-rolling feeding was previously hypothesized from observations of scars on the jaws of humpback whales and from earlier tagging projects. In the recent studies, researchers showed that this behavior happens for extensive periods of time at or near the seafloor, that it occurs in the presence of concentrations of sand lance (a preferred prey fish), and that the behavior is accompanied by the expansion of the animal's ventral (throat) pleats.

Information was collected through the use of DTAGs (synchronous motion and acoustic recording tags) and Crittercam™, National Geographic Society's underwater video and audio recording system.

Humpback whale with a scrape on its rostrum. Scientists say injuries such as this one are sometimes a result from bottom-feeding. (Credit: NOAA/Stellwagen Bank National Marine Sanctuary )"By visualizing the data with TrackPlot, we can actually see how the whale moves underwater and this enables us to discover different kinds of foraging behaviors," said lead author Colin Ware of the University of New Hampshire's Center for Coastal and Ocean Mapping. TrackPlot is a custom software tool for DTAG data that produces a ribbon-like image in three dimensions. "With these 3-D visualizations, we can follow the path of the whale from surface to seafloor along with all of the pitch, roll and heading changes while underway. By adding Crittercam video, we now get a more complete understanding of these various bottom feeding techniques," Ware said.

A side-roll is defined as a roll of between 45 and 135 degrees from a normal orientation along the seafloor - the most common version uses a 90 degree roll with a downward head pitch of about 30 degrees, which matches favorably with earlier speculative sketches of bottom feeding. A side-roll inversion involves rolls that continue past the 135 degree orientation position. One humpback used a technique that employed a repetitive sequence of moves approximately every 20 feet during which the animal rolled from a 90 degree position to an inverted position, with some 10 to 17 of these "scoops" per dive.

The whale's body orientation during bottom side-roll feeding is depicted in this computer-generated image. (Credit: Colin Ware, University of New Hampshire Center for Coastal and Ocean Mapping)Sand lance, also known as sand eels, tend to burrow into the sandy sediments at night or form nighttime horizontal schools close to the seafloor. In addition, Crittercam footage indicates that sand lance can form dense mats along the seabed during the day. The side roll feeding technique with extended pleats emphasizes width rather than height, resulting in more efficient feeding when encountering prey at or near the seafloor. Coordinated feeding may also help cluster prey or simply ensure that it does not escape. Crittercam footage also showed for the first time a head-to-head orientation for two animals that were side-rolling at the seafloor.

While this humpback bottom feeding behavior occurs at relatively slow speeds, it does involve the expansion of ventral pleats, which was once thought to require high speeds, as in lunging. The researchers theorize that humpback side rolls may be similar to the feeding technique of gray whales in the Pacific. The three types of bottom feeding techniques may be due to different prey distributions or may just reflect individual preferences between whales. In this 3D computer visualization, the roller coaster-like movement of a tagged humpback whale in Stellwagen Bank National Marine Sanctuary is captured over a nearly two-hour period. The whale traveled at depths ranging from 30 to 150 feet deep. The red and blue triangles along the ribbon show the whale's powerful fluke, or tail fin strokes that propel it through the water. The yellow sections along the ribbons indicate where bottom side-roll feeding occurs. (Credit: Colin Ware, University of New Hampshire Center for Coastal and Ocean Mapping)

Funding and additional support came from NOAA Office of National Marine Sanctuaries, NOAA Office of Marine and Aviation Operations, NOAA-University of New Hampshire Center for Coastal and Ocean Mapping, Office of Naval Research, National Oceanographic Partnership Program, Duke University Marine Laboratory, National Geographic Society, International Fund for Animal Welfare, Pacific Life Foundation and the Volgenau Foundation.

Designated in 1992, Stellwagen Bank National Marine Sanctuary encompasses 842 square miles of ocean, stretching between Cape Ann and Cape Cod offshore of Massachusetts. Renowned for its scenic beauty and remarkable productivity, the sanctuary supports a rich diversity of marine life including endangered great whales, seabirds, more than 60 species of fishes and hundreds of marine invertebrates.

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on
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