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."

View the original article here

First measurement flight: Research aircraft HALO explores trade wind clouds

Which climate effects do clouds have? Under what conditions will they warm or awesome the climate? Today, after greater than 5 years of preparation, the specifically outfitted research aircraft HALO (Thin Air and Lengthy Range Research Aircraft) will take off because of its first measurement flight in atmospheric research. Prof. Bjorn Stevens and Dr. Lutz Hirsch in the Max Planck Institute for Meteorology (MPI-M) leave Oberpfaffenhofen in Germany for any ten-hour flight to Barbados.

They'll operate numerous calculating instruments aboard HALO with respect to the German atmospheric research: "Each day we've eagerly looked forward to," states Stevens. "It's the initial pursuit to exploit the novel abilities of HALO to determine vertical profiles of aspects of atmospheric water -- like vapor, liquid and ice, both in cloud and precipitation forms, along with the aerosol contaminants where cloud tiny droplets form -- from the thin air. A brand new era of airborne atmospheric research." The aircraft, outfitted with a lot of advanced technology, is definitely an initiative by German climate and environment research institutions (see below) and it is run by the German Aerospace Center (DLR).

The flight belongs to the NARVAL project (Next-generation Aircraft Remote-Realizing for Validation Studies) and can supply the researchers with increased more information around the metabolic rate of tropical clouds (Fig. 1). The transatlantic plane tickets from Oberpfaffenhofen to Barbados will complement the stationary dimensions from the cloud observatory on Barbados. The collected data will lead to some better knowledge of cloud and precipitation processes and will assist you to reduce questions in climate models.

Remote realizing instruments, situated within the "Belly Pod" beneath the aircraft?s shell, will identify vertical profiles of humidity and temperature and also the distribution of tiny droplets and aerosols (Fig. 2). Furthermore, so-known as dropsondes is going to be launched throughout the flight. These radiosondes usually ascend from Earth with the aid of a weather balloon and perform dimensions enroute with the atmosphere. This time around, they'll be came by parachute and can glide back down.

The very first measurement flight is really a joint project from the MPI-M using the Meteorological Institute from the College Hamburg, DLR, Colleges of Perfume, Leipzig and Heidelberg and also the Forschungszentrum J?lich. It will require the researchers on the lengthy-haul flight to Barbados, in which the MPI-M cloud observatory is situated, and back. Ideally, comparison dimensions using the satellite CloudSat is going to be carried out throughout the plane tickets. The satellite measures the Atlantic clouds in trajectories crosswise towards the flight route. Short plane tickets of HALO in parallel using these satellite trajectories have the ability to ensure the satellite?s dimensions (Fig. 3): the aircraft flies in a lower altitude compared to satellite and may therefore identify the clouds a lot more accurate.

As a whole, the environment route Oberpfaffenhofen -- Barbados and back ought to be flown three occasions in December 2013 ("NARVAL South"). Throughout the 2nd flight, a nearby flight from Barbados eastward with the trade wind clouds is planned. The goal would be to identify clouds which are directly at risk of the Barbados cloud observatory and also to do a comparison towards the land-based cloud observatory data.

The 2nd area of the mission is going to be completed underneath the direction from the College Hamburg in The month of january ("NARVAL North"). HALO depends on Iceland to look at the backsides of fronts within the North Atlantic. The quantity of precipitation around the backsides of fronts is really a questionable subject in science because satellite findings and model information provide spun sentences. "Measured values are missing?? because ships don't sail during these typical storm zones" states principal investigator Prof. Felix Ament in the Center for Earth System Research and Sustainability (CEN), College of Hamburg. "A effective HALO mission could provide important details and eliminate a 'blank spot' into the spotlight of science."

The study aircraft HALO is definitely an initiative by German climate and environment research institutions. HALO is funded by: Federal Secretary of state for Education and Research (BMBF), German Research Foundation (DFG), Helmholtz Association, Max Planck Society, Leibniz Association, Free Condition of Bavaria, Karlsruhe Institute of Technology (Package), GFZ German Research Center for Geosciences, Forschungszentrum J?lich and German Aerospace Center (DLR)

View the original article here

Raindrop research dials in satellite predicting precision

Calling within the precision of satellite weather predicting may be the goal behind research into raindrop shape and size being carried out in the College of Alabama in Huntsville with a UAH doctorate student who's also an atmospheric researcher within the NASA Paths Intern Employment Program.

Patrick Gatlin states his work calculating the dimensions of raindrops using ground instruments offers an precision baseline that's then scaly as much as ground radar after which to satellite dimensions. He's co-author of the paper around the subject.

"That's truly the whole reason for calculating raindrops, is perfect for remote realizing reasons," Gatlin states. Scaling up precision from the small sensor on the floor to large sections of the world being observed from space requires very precisely adjusted instruments. "Our capability to properly illustrate rain fall utilizing a sensor wide is carefully associated with understanding how precipitation varies, right lower towards the individual raindrop and snowflake size."

Perfecting ground-level instrument findings, increasing the size of individuals to encompass ground-based radar after which going even bigger to build up accurate satellite calculating instruments is the easiest method to reduce error because the area under observation increases. "Before we invest in most this satellite instrumentation," Gatlin states, "let us make certain we have first got it right."

A coming large part of scaling up precipitation predicting is NASA's planned launch of their Global Precipitation Measurement (GPM) satellite toward the finish of Feb. UAH is really a mission contractor, headed in the college by Dr. Ray Carey, an connect professor of atmospheric science, and including UAH Earth System Science Center research researcher Matt Wingo, who's dealing with NASA in their flight facility in Wallops Island, Veterans administration.

"UAH designed the woking platform for a few of the ground-based instruments which will validate the data in the satellite," states Gatlin.

Transporting a sophisticated radar/radiometer system to determine precipitation from space, the GPM may be the core of the items is a global network of calculating satellites which will provide next-generation global findings of snow and rain. It'll function as a reference standard to unify precipitation dimensions from the constellation of research and operational satellites.

Through enhanced dimensions of precipitation globally, the GPM mission will assist you to advance knowledge of Earth's water and cycle, improve predicting of utmost occasions that create natural hazards and problems, and extend current abilities in making use of accurate and timely precipitation information.

In the own research, Gatlin has ranged from Iowa and Oklahoma to Canada, Finland, Italia and France. Instead of raindrops, the Canadian research is built to collect snowflake images to be able to enhance the precision of calculating products for snowfall.

In every locale, a built-in network of ground-level calculating products happen to be used, such as the Parsivel2, a disdrometer that measures the particle size and velocity of raindrops falling via a laser. Also being used are a couple of-dimensional video disdrometers, designed to use two video angles to produce 2-D pictures which allow resolution of raindrop shapes. A relevant video disdrometer on loan from frequent research collaborator Colorado Condition College is situated around the UAH campus behind Cramer Hall.

Throughout a area study, the instruments on the floor take dimensions while an airplane flies with the clouds to gather actual raindrop information and the other flies high over the clouds with remote realizing equipment to imitate satellite radar recognition. Is a result of all of the measurement techniques are in comparison.

Enhanced satellite-based precipitation dimensions will improve both rain fall and snowfall forecasts on the global scale, Gatlin states. "I will be calculating snow and rain in certain places that we have never measured it before." The opportunity to better measure raindrop size may also have effect on tornados predicting, as small raindrops result in greater evaporation rates which have been correlated with bigger and much more powerful microbursts by UAH's Dr. Kevin Knupp yet others.

Gatlin is going to finish off a worldwide study focusing just on large raindrops 5 millimeters in dimensions and bigger. These drops take time and effort to capture within the small calculating area given by calculating instruments, and thus their observation is rare. Gatlin states from 224 million drops he's investigated, only 8,000 happen to be 5 mm or bigger.

"Despite the fact that large raindrops might have the finest effect on radar dimensions, we do not have advisable of the concentration," he states. "What I have been doing is getting together all of the raindrop data bases which have collected various rain fall data utilizing the same techniques."

Oddly enough, while Sumatra supports the recognition of getting the finest quantity of large drops overall, the biggest drop collected in the study fell via a calculating device in the UAH campus. It measured 9.1 mm and was created inside a hailstorm whenever a falling bit of hail melted before landing.

View the original article here

'Standing on the comet': Rosetta mission will lead to space weather research

A comet-bound spacecraft which has been in sleep mode in excess of 2 yrs is scheduled to wake on the morning of Jan. 20 -- beginning the house stretch of their decade-lengthy journey to some mile-wide ball of rock, dust and ice.

If all goes as planned, Rosetta -- a ecu Space Agency-brought mission which involves College of Michigan engineers and researchers -- would be the first craft to really find a comet in addition to track it to have an extended time period.

The Philae lander will latch onto the main of comet 67P/Churyumov-Gerasimenko in November and also the orbiter will operate before the finish of 2015. No mission has ever attempted this kind of in-depth take a look at one of these simple artefacts from the earliest times of our photo voltaic system.

Engineers at U-M's Space Physics Research Lab built electronic components to have an onboard instrument that's thought is the most sensitive available ever flown wide. Along with a team of scientists will engage in the mission science too.

While the majority of the large questions Rosetta aims to reply to cope with the foundation and evolution from the photo voltaic system, U-M researchers can make a distinctive contribution that may provide very practical experience into the way the sun and planets interface today.

They'll evaluate dimensions taken in the comet to review photo voltaic wind interactions that can result in photo voltaic storms. The photo voltaic wind is really a stream of billed contaminants coming in the sun. Photo voltaic storms are bursts of activity that may threaten astronauts and damage Earth's satellites and electric power grid.

"The way the photo voltaic wind works is among the greatest outstanding questions regarding the photo voltaic system today. By studying the way it interacts with cometary gases, we are able to become familiar with a lot concerning the composition from the photo voltaic wind," stated Tamas Gombosi, the Rollin M. Gerstacker Professor of Engineering within the Department of Atmospheric, Oceanic and Space Sciences.

Gombosi and the research group are leaders within the area of space weather. One they developed was lately adopted through the national Space Weather Conjecture Center.

In the sun's equator, the wind travels rather gradually, Gombosi stated. It moves faster at high latitudes. Interactions backward and forward types can result in magnetospheric storms. Earth orbits close to the equator, therefore it is difficult to read the fast wind from your standpoint.

"But comets go through everything. Using their help, we are able to read the fast photo voltaic wind," Gombosi stated.

Gombosi along with other U-M scientists will engage in additional Rosetta goals. They'll study and simulate how rapidly the comet outgases material from the nucleus to the tail because it rings round the sun. They'll engage in analyzing what elements have been in the comet's tail, atmosphere and ionosphere, in addition to how quickly the electrified contaminants within the ionosphere are traveling.

Michael Combination, the Freeman Devold Burns Collegiate Research Professor within the Department of Atmospheric, Oceanic and Space Sciences, is really a co-investigator on several instruments. He'll consider the speed where the comet's core is sublimating, or turning from the solid right into a gas, and he'll work on the team that's examining individuals gases. They'll explore the amount of deadly carbon monoxide and co2, for instance. They cannot identify co2 from Earth.

"It's tough to observe a few of the chemical species when they are far and faint. Co2 is most likely the 2nd most abundant species for the most part comets, but it is not been noticed in the 1000's we have checked out from Earth," stated Combination, that has analyzed comets in excess of 3 decades.

Comets -- small rock and ice physiques -- were contained in the nebula that created the photo voltaic system and also have been revolving about since in far, cold devices either just beyond the orbit of Neptune or perhaps a quarter from the distance towards the nearest star. For researchers, they are ancient items which help them know how the photo voltaic system created and developed. They are thought to possess shipped Earth's oceans and possibly the seed products of existence in organic materials.

"People make use of the example it's experienced the freezer within the last 4.5 million many introduced set for convenient study. So we are searching around we are able to at how a way the photo voltaic system was 4.5 billion years back,Inch Combination stated.

Comet 67P/Churyumov-Gerasimenko is among the littlest physiques humans have ever attempted to find. Its gravity is all about 1,000 occasions under those of Earth.

"Around the lander, there is a camera that may look straight lower like you are standing and searching in the ground. Plus there is a breathtaking camera that may watch out and find out an image from the horizon. It will be fun to determine what this landscape appears like,Inch Combination stated. "It will be like sitting on a comet."

View the original article here

Research finds new way to identify which El Niño events will have biggest impact on U.S. winter weather

February 7, 2013

El Niño, warmer than average waters in the Eastern equatorial Pacific (shown in orange on the map), affects weather around the world. A new study, just published in the February 2013 issue of the Journal of Climate, describes an atmospheric El Niño signal that is very strongly associated with U.S. winter weather impacts.

Download here (Credit: NOAA Visualization Lab)

Weather forecasters have long known that El Niño events can throw seasonal climate patterns off kilter, particularly during winter months. Now, new research from NOAA and the University of Washington suggests that a different way to detect El Niño could help forecasters predict the unusual weather it causes.

A network of buoys that spans the Pacific, the TAO-Triton array, observes conditions in the upper ocean and is essential for forecasting El Niño months in advance, and for monitoring it as it grows and decays. A new study, just published in the February issue of the Journal of Climate, describes an atmospheric El Niño signal that is very strongly associated with U.S. winter weather impacts. Ed Harrison, Ph.D. of the NOAA Pacific Marine Environmental Laboratory in Seattle and Andrew Chiodi, Ph.D., of the NOAA Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington, co-authored the paper.

“When it comes to El Niño’s weather impacts, we are always looking for ways to improve our forecasting skill,” said Harrison. “Our goal is to extract the most useful information to predict El Niño seasonal weather anomalies.”

Harrison and Chiodi looked at all El Niño events that were identified by sea surface temperature measurements since 1979. They then examined satellite imagery for these events and found that a subset of the events showed a sharp dip in heat radiating from the tops of deep convective clouds, an indicator known as outgoing long-wave radiation or OLR. When comparing the El Niño events to historical weather records, the scientists found that the El Niño events with drops in OLR were the ones most likely to play havoc with winter weather.

They also found that El Niño events with no corresponding drop in OLR did not produce statistically significant anomalies in weather patterns. The dip in heat from deep convective clouds usually occurred before winter, so the timing of the signal could help forecasters improve winter seasonal outlooks, the scientists said.

“By sorting El Niño events into two categories, one with OLR changes and one without, forecasters may be able to produce winter seasonal outlooks with more confidence than previously thought possible,” Harrison said.

El Niño refers to a warming of waters along the equator in the Eastern Pacific Ocean. Through its influence on the atmosphere, El Niño shifts tropical rainfall patterns which causes further shifts in weather around the globe, including milder winters in western Canada and parts of the northern United States and wetter winters in the some southern states.

Industry sectors from energy and construction to transportation and tourism are keenly interested in how El Niño will affect their costs. El Niño-influenced weather can affect fuel oil demand, travel delays, and retail sales. Better accuracy in El Niño predictions could help industry to prepare for its impacts more efficiently.

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels at social media channels.

View the original article here