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DOE/SC-ARM-11-024
ARM Climate Research Facility ANNUAL REPORT – 2011
Recovery Act HIGHLIGHTS
October 2010
• DopplerlidarstestedattheAtmosphericRadiationMeasurement(ARM)ClimateResearchFacility’sSouthernGreatPlains(SGP)site.• FinalinstallationcompletedforthethreeX-bandscanningARMprecipitationradars(X-SAPRs)atSGP.• WeighingbucketraingaugeinstalledatTropicalWesternPacific(TWP)siteinDarwin,Australia.
November 2010• AerosolchemistryspeciationmonitorincorporatedintotheAerosolObservingSystem(AOS)atSGP.• DatacommunicationtowersandradioequipmentforallSGPradarsitesinstalled.• FirstoperationalRamanlidarinthetropicsbegangatheringdatainDarwin.
December 2010• AllthreeX-SAPRscompletedacceptancetestingatSGP.• Ka-bandARMzenithradar(KAZR)replacedmillimeterwavelengthcloudradar(MMCR)atSGP.• Newatmosphericemittedradianceinterferometer(AERI)andDopplerlidarinstalledattheDarwinsite.
January 2011• Highspectralresolutionlidar(HSRL)and3-channelmicrowaveradiometerjoinedtheARMMobileFacility(AMF)
installationinSteamboatSprings,Colorado.• NewAERIinstalledatSGP.
February 2011• C-bandSAPRandW/Ka-bandscanningARMcloudradar(SACR)installedatSGP,completingthenewsuiteoffivescanningradars.
March 2011• HSRLandautosondelauncherinstalledatNorthSlopeofAlaska(NSA)siteinBarrow,Alaska.• Fast-forwardscatteringprobeandfastclouddropletprobeaddedtotheARMAerialFacility(AAF)instrumentsuite.
April 2011• C-SAPRonManusIsland,PapuaNewGuinea,installed,representingthefirstoperationalprecipitationradarintheTWParea.
May 2011
• NewKAZRbeganoperationatNSA,representingthefinalreplacementoftheoriginalMMCRsthroughouttheARMFacility.
June 2011• AcceptancetestingcompleteforX-SAPRatNSA.• Dual-frequencyW/Ka-bandandX/Ka-bandSACRsacceptedfordeploymentatDarwinandManusIslandandaspartoftheAMF.
July/August 2011• X/Ka-SACRinstalledinDarwin.• Threenew3-channelmicrowaveradiometerspassedacceptancetestsatSGP.
September 2011
• FinalRecoveryActinstrumentsreceived,andinfrastructureenhancementscomplete.
ARM Climate Research Facility ANNUAL REPORT – 2011
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Facility Overview ...........................................................................................................................................4
The Importance of Clouds and Radiation to Climate Change ........................................................5
ARM Climate Research Facility .............................................................................................................6
Cooperation and Oversight Enable Success .....................................................................................7
Budget Summary and Facility Statistics ...............................................................................................8
Key Accomplishments .................................................................................................................................9
Featured Field Campaigns ..................................................................................................................10 •MidlatitudeContinentalConvectiveCloudsExperiment •StormPeakLabCloudPropertyValidationExperiment
Research Highlights ...............................................................................................................................14 •ANewSurface-BasedApproachforDeterminingCloudAlbedo •IceGenerationandGrowthinArcticMixed-PhaseClouds •ARMDataRevealtheStrongestLong-TermNetImpactofAerosolsonCloudsandPrecipitation •LookingforAerosolinAlltheRightPlaces •CharacterizingCloudsatArcticAtmosphericObservatories •AnvilCloudsofTropicalMesoscaleConvectiveSystemsinMonsoonRegions
Infrastructure Achievements ................................................................................................................19 •RecoveryAct •SiteOperations •DataDelivery •Communication,Education,andOutreach
Field Campaign Summary .........................................................................................................................25
On the cover: During April and May of 2011, the Midlatitude Continental Convective Clouds Experiment took place at the ARM SGP site in central Oklahoma. The goal of this campaign was to document and monitor precipitation, clouds, winds, and moisture in order to provide a holistic view of convective clouds. For more information, see the FeaturedFieldCampaigns section of this report.
Table of CONTENTS
ARM Climate Research Facility ANNUAL REPORT – 2011
Facility OVERVIEW
ARM Climate Research Facility ANNUAL REPORT – 2011
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Review panel states ARM Facility “without peer.” Everythreeyears,DOEOfficeofScienceuserfacilitiesundergoareviewtoevaluatetheireffectivenessincontributingtotheirrespectivescienceareas.ThelatestARMFacilityreviewwasconductedinmid-Februarybyasix-memberreviewpanel.ThepanelconvenedinPoncaCity,Oklahoma,nearARM’sSGPsitetoconducttheirreview.TheirfirstagendaitemwasanSGPsitetour,whichprovidedareal-timeexampleofthescopeandexpertiseofsiteoperationsandincludedademonstrationofthesite’snewlyinstalledprecipitationradars.TheremainderofthereviewconsistedoftechnicalpresentationsbyFacilitymanagement.Notably,inadebriefingfollowingthereview,thepanelstatedthatARMwasa“world-classfacilitywithoutpeer.”
The Importance of Clouds and Radiation to Climate Change
TheEarth’ssurfacetemperatureisdeterminedbythebalancebetweenincomingsolarradiationandthermal(orinfrared)radiationemittedbytheEarthbacktospace.Changesinatmosphericcomposition,includinggreenhousegases,clouds,andaerosols,canalterthisbalanceandproducesignificantclimatechange.Globalclimatemodels(GCMs)aretheprimarytoolforquantifyingfutureclimatechange;however,significantuncertaintiesremainintheGCMtreatmentofclouds,aerosol,andtheireffectsontheEarth’senergybalance.
In1989,theU.S.DepartmentofEnergy(DOE)OfficeofSciencecreatedtheAtmosphericRadiationMeasurement
(ARM)Programtoaddressscientificuncertaintiesrelatedtoglobalclimatechange,withaspecificfocusonthecrucialrole
ofcloudsandtheirinfluenceonthetransferofradiationintheatmosphere.
Designatedanationaluserfacilityin2003,theARMClimateResearchFacility(ARMFacility)isascientificuserfacilityforobtaininglong-termmeasurementsofradiativefluxes,cloudandaerosolproperties,andrelatedatmosphericcharacteristicsindiverseclimateregimes.
TheARMFacilitynowprovidesunmatchedmeasurementcapabilitiesthatpermitthemostdetaileddocumentationofcloudcharacteristicsandtheirevolutioneverobtainedanywhereintheworldandwillhelpscientistsreducethetwolargestuncertaintiesinclimatemodels:therolesofcloudsandaerosolsinclimatechange.
ThisreportprovidesanoverviewoftheARMFacilityandaselectionofachievementsforeachinfiscalyear(FY)2011.
Researchers use data collected from ARM ground-based and airborne instruments to study the natural phenomena that occur in clouds and how those cloud conditions affect incoming and outgoing radiative energy.
ARM Climate Research Facility ANNUAL REPORT – 2011
ARM Climate Research FacilityThroughtheARMFacility,DOEfundedthedevelopmentofseveralpermanent,highlyinstrumentedgroundstationsforstudyingcloudformationprocessesandtheirinfluenceonradiativetransfer,andformeasuringotherparametersthatdeterminetheradiativepropertiesoftheatmosphere.Toobtainthemostusefulclimatedata,instrumentationwasestablishedatthreelocalesselectedfortheirbroadrangeofclimateconditions.
• Southern Great Plains (SGP)—includesaheavilyinstrumentedCentralFacilitynearLamont,Oklahoma,andsmallersatellitefacilitiescoveringa150-kilometer-by-150-kilometerareainOklahomaandKansas.
• Tropical Western Pacific (TWP)—includesthreesitesspanningtheequatorialregionfromIndonesiatothedateline:Darwin,Australia;ManusIsland,PapuaNewGuinea;andNauruIsland.
• North Slope of Alaska (NSA)—includesasiteatBarrowneartheedgeoftheArcticOcean.
Eachsiteoperatesadvancedmeasurementsystemsonacontinuousbasistoprovidehigh-qualityresearchdatasets.Thecurrentgenerationofground-based,remotesensinginstrumentsincludesthree-dimensional(3D)cloudandprecipitationradars,Ramanlidar,infraredinterferometers,aerosolobservingsystems,andseveralfrequenciesofmicrowaveradiometers,amongothers.
GOAmazon 2014 workshop identifies challenges, opportunities.InJuly2011,DOE’sOfficeofBiologicalandEnvironmentalResearch(BER)heldatwo-dayworkshoptoidentifykeyscientificchallengesandopportunitiesassociatedwithamajorfieldcampaign—GreenOceanAmazon2014,orGOAmazon2014—takingplaceinManaus,Brazil.Duringthecampaign,severalBER programs,includingtheARMFacility,willdeployobservationalresourcestoobtaindataforstudyingoneofthemostcomplexclimateprocessesonEarth:theatmosphere-cloud-terrestrialtropicalsystemsthatdrivetropicaldeepconvectionintheAmazon.
Morethantwodozenprocessandmodelingscientistswithexpertiseinatmosphericandterrestrialecosystemresearchparticipatedintheworkshop,alongwithBERprogrammanagersandinvitedspeakers.TheoutcomesofthisworkshoparesummarizedintheGOAmazon2014WorkshopReport(DOE/SC-0141), includingappendicescontaininganagenda,participantslist,andmeasurementcapabilitiescollection.
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ThroughtheAmericanRecoveryandReinvestmentActof2009(RecoveryAct),theARMFacilityreceived$60milliontopurchaseanddeploynewandupgradedinstrumentation,equipment,andinfrastructure.TheARMFacility’sinstrumentarraysrepresentsomeofthemostsophisticatedtoolsavailableforconductingatmosphericresearch.
MeasurementsobtainedatthepermanentsitesaresupplementedwithdataobtainedfromintensivefieldcampaignsusingtheARMMobileFacilities(AMF)orARMAerialFacility(AAF).
Inaddition,dataonsurfaceandatmosphericpropertiesarealsogatheredthroughforecastmodels,satellites,andvalue-addedprocessing.Oncecollected,theinformationissenttothesitedatasystemsandcarefullyreviewedforquality.ApproveddataarethenstoredintheARMDataArchive(www.archive.arm.gov)forusebytheatmosphericsciencecommunity.
Usingthesedata,scientistsarestudyingtheeffectsandinteractionsofsunlight,radiantenergy,andcloudstounderstandtheirimpactontemperatures,weather,andclimate.Aspartofthiseffort,ARMpersonnelanalyzeandtestthedatafilestocreateenhanceddataproducts,whicharealsomadeavailableforthesciencecommunityviatheARMDataArchivetoaidinfurtherresearch.
Cooperation and Oversight Enable Success NineDOEnationallaboratoriesandnumerousgovernmentagencies,universities,privatecompanies,andforeignorganizationscontributetotheARMFacility.Eachentityservesavitalroleinmanagingandconductingtheoperationandadministrationoftheuserfacility.
TheARMFacilityisdirectedbyDOE Headquarters.AnInfrastructure Management Boardcoordinatesthescientific,operational,data,financial,andadministrativefunctionsoftheARMFacility.An11-memberFacility Science Board,selectedbytheARMProgramDirector,servesasanindependentreviewbodytoensureappropriatescientificuseoftheARMFacility.
Cloud radar overhauled and renamed.Inmid-December2010,anewradarbeganatwo-weekpre-operationaltestalongsidetheARMMMCRatSGP.Thisushersinaneweraforthefixed-positionclouddatapreviouslyacquiredbytheMMCR.TheMMCR(right-handside)hasbeenretiredatallofARM’spermanentresearchsitesinfavorofthenewKAZR(left-handside),whichisexpectedtoprovidesignificantlyimprovedsensitivity.
Sinceitbeganoperatingin1996,theMMCRsetthestandardforprovidingdataaboutcloudboundaries,verticalvelocity,andreflectivity.ThroughtheRecoveryAct,ARMwasprovidedtheopportunitytosignificantlyupdatetheradar’stechnology.Asaresult,theKAZRisessentiallyanewradar.Sourcedbyadifferentmanufacturer,itusesonlytwoofthesamecomponents—theantennaandtransmitter—asthepreviousmodel.Althoughtheusercommunitymustfamiliarizeitselfwithanewinstrumentname,theingesteddataformatisassimilaraspossibletothehistoricalMMCRingest.Inaddition,thechangeshouldbetransparentforresearcherswhousedatafromtheMMCRthroughthewidelyusedActiveRemoteSensingofClouds,orARSCL,value-addedproduct(VAP).
ARM Climate Research Facility ANNUAL REPORT – 2011
Fiscal Year 2011 Budget Summary and Facility Statistics
FY2011 Budget ($K)
Infrastructure 45,694
User Statistics for the Period of October 1, 2010–September 30, 2011
ARM Facility Component Unique Scientific Users
Unique Non-Scientific Users
Totals
AMF1(Azores) 19 16 35
AMF2(Colorado) 156 43 199
NSA 41 40 81
SGP 149 178 327
TWP 34 28 62
DataManagementFacility 48 67 115
Archive 770 75 845
Total 1217 447 1664
Operational Statistics for the Period of October 1, 2010–September 30, 2011
Data Availability (%)SITE GOAL ACTUAL
AMF 0.95 0.77
NSA 0.90 0.90
SGP 0.95 0.93
TWP 0.85 0.94
Site Average 0.90 0.92
Site average is calculated for fixed sites only.
The AMF did not operate during the fourth quarter of FY2011, so the average is calculated based on data availability during the first three quarters.
2605
470667
2983
Visitor Days by Site
AMF &Other
SGP NSA TWP
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Key ACCOMPLISHMENTS
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Featured Field CampaignsInadditiontoprovidingcontinuousdatacollectionsfromitsfixedsites,theARMFacilitysponsorsfieldcampaignsforscientiststoobtainspecificdatasetsortotestandvalidateinstruments.ThefollowingpageshighlightkeycampaignsconductedinFY2011.AsummaryofallARMFacilitycampaignsthatbeganinFY2011isavailableattheendofthisreport.
Midlatitude Continental Convective Clouds Experiment
BeginningApril2011,theARMSGPsiteinnorth-centralOklahomahostedtheMidlatitudeContinentalConvectiveCloudsExperiment(MC3E),thefirstmajorfieldcampaigntotakeadvantageofnumerousnewradarsandotherremotesensinginstrumentationinstalledthroughoutthesitewithfundingfromtheRecoveryAct.
Thecampaignwashighlycomplex,involvingfiveremoteradiosondesites,supplementalradars,coordinatedaircraft,andadensenetworkofdozensofraingaugesanddisdrometers.TheNationalAeronauticsandSpaceAdministration(NASA)alsosponsoredmorethan100flighthourswithtwodifferentaircraft:theER-2andtheUniversityofNorthDakota’s(UND)Citation.TheCitationcarriedtwoprobesbelongingtotheAAFandpurchasedin2010throughtheRecoveryAct.ByheavilysupplementingtheroutinemeasurementsfromtheSGPsite,thegoalofMC3Ewastoprovidethemostcompletecharacterizationofconvectivecloudsystemsandtheirenvironmentthathaseverbeenobtained,providingdetailsfortherepresentationofcumuluscloudsincomputermodelsthathaveneverbeforebeenavailable.
LatespringintheMidwestgeneratedsomeofthemostsevereweathereverrecordedinthestateofOklahomaandproducedavarietyofconvectivecloudconditions.TheseconditionsprovidedMC3Eresearcherswithampleopportunitytostudythecomprehensivedatasetcollectedbythewidearrayofinstrumentsthroughoutthestudydomain.
AsastormsystemmovedovertheSGPCentralFacilityonMay20,2011,itwassampledbyalltheground-basedinstrumentsandradarsandsampledfromaboveandwithinbyaircraftflyingwell-definedcross-sectionsovertheCentralFacility.AtornadoonMay23,2011,wasobservedbythenewC-SAPRabout50kilometerstothenortheastoftheCentralFacility.
OnMay24,2011,anotherseriesofstormcellsspawnednumeroustornadoesthattoucheddowninOklahoma.Oneofthesetornadoespassedwithinaquarter-mileofSGPinstrumentslocatedatasmallSGP“extendedfacility”inElReno.AlthoughoutsideoftheMC3Eradardomain,instrumentationatanOklahomaMesonetsitecollocatedwiththeARMsiteatElRenorecordedwindsofaround150milesperhourandanextremepressuredropasthetornadopassedthrough.
During MC3E, convective clouds like these were measured by NASA research aircraft and numerous radars throughout the SGP site, including ARM’s radars at the SGP Central Facility.
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Results: PreliminaryanalysisofthedatafromtheMC3Ecampaignindicatesthatawidevarietyofcloudandprecipitationconditionsweresampled,includingstrongconvectivelines,isolatedconvectivecells,widespreadstratiformrain,elevatedweakconvection,boundary-layerclouds,andmid-orupper-levelclouds.Thedatacollectedbefore,during,andaftertheseeventswillbeusedtoinvestigateatmosphericprocessesimportantfortheparameterizationofconvectivecloudsinlarge-scaleatmosphericmodels.Themeasurementsthatwillbeusedforthisanalysisinclude:
• Large-scaleradiosondearray:Morethan25participantslaunched4–8weatherballoonsperdayfrom6differentsites,totalingmorethan1400launchesoverthecourseofthesix-weekfieldcampaign.Theprofilesofatmosphericstatevariableswillprovideimportantinformationontheenvironmentinwhichconvectivecloudsprogressthroughtheirlifecycle.Theseprofilesarealsoanimportantinputtolarge-scaleatmosphericmodels.
• NewARMscanningradarsystems:Theseinstrumentsprovidednewobservationsonthedetailsofcloudandprecipitationsystemsduringallstagesoftheirlifecycle.Thevarietyofobservationsatdifferentwavelengthsallowedtheobservationofafullspectrumofcloudsfromsmallnon-precipitatingcloudstolarge,organizedstormsystems,includingsevereweather.
• Coordinatedaircraftobservations:TheNASAER-2andUNDCitationflewcoordinatedflightsinmanyofthedifferentprecipitatingsystemsseenduringMC3E,providingaviewfromabovethecloudsandmeasurementsofthecloudandprecipitationmicrophysicswithintheclouds.
• Disdrometernetwork:Anetworkofmorethan20disdrometersprovidedinformationonthevariabilityofprecipitationdropsizedistributionsatsub-stormsizescalesandinsightsintotheformation,growth,andbreak-upprocessesofthedrops.
Thesecasesprovideanunprecedented,comprehensivedatasetforstudyingcloudandprecipitationprocessesandimprovingclimatemodelsforyearstocome.
These three radar images show observations of a strong convective system with severe weather that moved through the MC3E domain on the afternoon of May 23, 2011. From top to bottom, data were gathered by the southwest X-SAPR, the C-SAPR, and the southeast X-SAPR.
Storm Peak Lab Cloud Property Validation Experiment
FromOctober2010throughApril2011,adensecollectionofremotesensinginstrumentsgathereddatafromthecloudsatfourdifferentelevationsonMountWernerintheSteamboatSpringsskiareaaspartoftheStormPeakLabCloudPropertyValidationExperiment(STORMVEX).Scientistswillusethesedatatostudyhowclouds—especiallythosethatproducerainandsnow—evolveinmountainousterrain.TheywillusethedatatoverifytheaccuracyofmeasurementsusedincomputermodelsoftheEarth’sclimatesystem.
Thegoalbehindthemultipleelevationinstrumentstrategywastocapturea“verticalprofile”ofthecloudsthatmoveacrossthemountainslopes.Todothis,thedepartmentdeployedAMF2withnearlytwodozenremotesensinginstrumentstotakecontinuousmeasurementsfromthreedifferentelevationsbeneathStormPeakLab(SPL),apermanentatmosphericresearchlaboratoryatthetopofMountWerner.SeveraloftheinstrumentsdeployedduringthefieldcampaignwerefundedbytheRecoveryActandhadneverbeendeployedbefore.ThecampaignalsorepresentedtheinauguraldeploymentofARM’ssecondmobilefacility.
Becausecloudsaresodynamicandcancontainice,water,oramixtureofthetwo,theycontinuetobeoneofthehardestcomponentsoftheclimatesystemforscientiststomodelaccurately.Ground-basedinstrumentsprovidemoregeographicandtemporalcoverageofthesecloudsystems.Instrumentsonthegroundaretypicallyusedtoobtain—or“retrieve”—measurementsthatarerelatedindirectlytoimportantcloudprocesses.Inferringthesecloudprocessesrequiresdevelopmentofmathematicalformulas,oralgorithms,toconvertthemeasurementsintocloudproperties.Inordertoensuregreateraccuracyoftheground-basedmeasurements,comparisonsaremadewithmoredirectairbornemeasurements.Duringtheexperiment,SPLwasin-cloud,andtheirarrayofmeasurementsservedasaproxyforaircraftmeasurements.
Aboutadozeninstrumentswerelocatedonthevalleyfloor,nearthebaseofMountWerner,whereresearchersalsolaunchedweatherballoonsseveraltimesaday.MoreinstrumentswerelocatedoutsideThunderheadLodge,amainthoroughfarefortheskiarea.AthirdinstrumentcollectionwaslocatedneartheChristiePeakExpresschairlift.SPL,atthetopofthemountain,hostedseveralinstrumentsinadditiontoitspermanentcollection.
Inaddition,theNationalScienceFoundation-supportedColoradoAirborneMultiphaseCloudStudy(CAMPS)providednearly100hoursofresearchflighttimeovertheSteamboatareabytheUniversityofWyomingKingAirresearchaircraft.InstrumentsandsupportfromNASA’sJetPropulsionLabwerealsocriticalelementsofSTORMVEX.
The SWACR gathered cloud properties data outside the Thunderhead Ski Lodge in Steamboat Springs, Colorado.
During STORMVEX, the AOS was located at Christie Peak, along with a sign describing the various elements of the study.
ARM Climate Research Facility ANNUAL REPORT – 2011
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Results: Understandingthecomplexmicrophysicalprocessesthatlinkairmotionswiththeproductionoffrozenprecipitationinliquidphasecloudsisanimportantbutpoorlyunderstoodprocess.STORMVEXbenefitedfromoneofthesnowiestwintersonrecordinthenorthernColoradoRockyMountainsandenjoyedcloudcoverexceeding60percent.Measurablesnowwasrecordedonmorethan75daysofthecampaign,withmajorsnowfallexceeding10centimetersperdayonapproximately20ofthosedays.Totalmeasurablesnowfallexceeded800centimeters.
Duringthecampaign,AMF2’smajorassetsoperatednearlyflawlesslywithnomajordowntimeofthescanningW-bandcloudradar(SWACR).TheSWACRcollectedterabytesofDopplerspectraandvolumetricradarreflectivitydatafromanareaextending10kilometersinalldirections,includingthecomplexterrainoftheParkRangemountains.
RadiosondeswerelaunchedonaregularschedulefromthevalleybyAMF2andanintrepidcadreoflocalvolunteers.Simultaneously,aerosoldatawerecollectedbytheAOSlocatedonChristiePeakandbyinstrumentsatSPL.AlsoatSPL,measurementsofclouddroplets,icecrystals,andsnowflakeparticleconcentrationswerecollected.InadditiontoSPL’sregularstaff,ateamofgraduatestudentsfromtheUniversityofUtahandtheUniversityofWashingtonmaintainedSPL’sinstrumentsinconditionsthatwereoftenchallenging.
Analysisofthedatasetisjustbeginningtogeneratescientificresults.EarlyanalysisoftheSWACRdataisshowingameasurablepolarimetricsignaturetosnowflakecrystalstructure.TheaerosoldataarerevealingauniquenucleationprocessthatoccurreddailyatapproximatelythesametimeintheafternoonatbothSPLandatChristiePeak.Finally,theSWACRDopplerspectraaredisplayingawelldefinedsignatureoforientedsnowflakesaswellasdepictingauniquedistributionofprecipitation.
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This map of the STORMVEX sites illustrates the various elevations at which measurements were gathered.
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ARM Climate Research Facility ANNUAL REPORT – 2011
Research HighlightsScientistsaroundtheworldusedatafromtheARMFacilityfortheirresearch.InFY2011,ARMdatawerecitedinatotalof380publications.ThefollowingpagesfeatureaselectionofARMresearchhighlightsfromthesepublications.Formorepublicationsinformation,searchtheARMPublicationsDatabase:
www.arm.gov/publications/publist
A New Surface-Based Approach for Determining Cloud Albedo
OneoftheARMFacility’slongestandbestmeasurementsissurface-basedsolarradiation.Withinthisstudy,researcherscapitalizedonlong-termandhigh-resolutionradiationmeasurementstoaddressthreeoutstandingissuesrelatedtocloud-radiationinteractions.First,itistheoreticallyshownthatrelativesurfacecloudradiativeforcing,definedasthedifferencebetweenclear-skyandall-skysurfacedownwellingsolarradiationnormalizedbytheclear-skysurfacedownwellingsolarradiation,approximatelyequalscloudfractiontimescloudalbedo.Second,basedonthisanalyticalexpression,anewmethodwasdevelopedtoestimatecloudalbedofrommeasurementsoftherelativesurfaceradiativeforcingandcloudfraction.Thenewsurface-basedmethodisevaluatedbycomparisonwithcoincidentandcollocatedsatellitemeasurements.Finally,usingthenewformulation,high-resolution,
decade-longdataonrelativecloudradiativeforcingandcloudalbedoaregeneratedfromtheconcurrentsurface-basedmeasurementsofdownwellingshortwaveradiationfluxandcloudfractioncollectedatSGPsince1997.Thesenewdataarethenusedtoquantifymultiscale(diurnal,annual,andinter-annual)variationandco-variationofsurfacecloudradiativeforcing,cloudfraction,andcloudalbedo.
Thisstudydemonstratestheutilityoftheconceptofrelativecloudradiativeforcing,itsquantitativerelationshipwithcloudfractionandcloudalbedoinstudyingcloud-radiationinteractions,andthepotentialforitsapplicationtootherARM-likesiteswhereradiationisroutinelymeasured.Asimilarframeworkcanbeappliedtoevaluateclimatemodelsintermsofparameterizationofprocesscoupling,anaspectthathasnotreceivedsufficientattention.
(Reference:Liu,Y,WWu,MPJensen,andTToto.2011.“Relationshipbetweencloudradiativeforcing,cloudfractionandcloudalbedo,andnewsurface-basedapproachfordeterminingcloudalbedo.”Atmospheric Chemistry and Physics11(14):7155–7170,doi:10.5194/acp-11-7155-2011.)
2011 Publications Summary
Category Total
AbstractsorPresentations
239
BookChapters 1ConferencePapers 117JournalArticles 117TechnicalReports 23Total 380
Comparison of cloud albedo derived from the new surface-based approach and the Geostationary Operational Environmental Satellite (GOES) satellite measurements at SGP. The red and black lines represent the linear fit to all the data points and perfect match, respectively. The different panels account for the different percentage of the occurrence of single-layer clouds.
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Ice Generation and Growth in Arctic Mixed- Phase Clouds
Inexperiencingsignificantchangesinitssurfaceairtemperature,sea-icecover,atmosphericcirculation,precipitation,snowfall,biogeochemicalcycling,andlandsurface,theArctichasprovensensitivetoglobalclimatechanges.Advancedknowledgeofcloud-radiation-dynamicsfeedbacksisneededtounderstandthesecurrentchangesandtoreliablyforecastfuturechanges.DuetotheArctic’slocationanduniquethermodynamicconditions,knowledgeofcloudsinthemiddlelatitudecannotbefullyappliedtoit.Forexample,Arcticcloudsaredominatedbystratiformmixed-phaseclouds,whichhaveamuchloweroccurrenceinthemiddlelatitude.Long-termobservationsatNSAofferopportunitiestounderstandphysicalprocessescontrollingthesecloudsandtheirrolesintheArcticclimatesystem.
Bycombiningmultipleremotesensormeasurements,analgorithmwasdevelopedtoretrieveliquid-andice-phasepropertiesinthesemixed-phaseclouds,whichofferneededinformationforprocessstudies.Basedonsixyears(1999to2004)ofobservationalandretrievaldataatNSA,researchersdeterminedthespringseasonhasdistinctice-liquidmasspartitioninArcticmixed-phaseclouds.Theanalysesofsurfacesamplingsandlidardepolarizationprofilesindicatedahighoccurrenceoflong-rangetransporteddustaerosolsinthespringseason,whichpointstoastrongseasonaldustimpactonicegenerationinArcticmixed-phaseclouds.DuetotheArctic’slongwinterandlowsunelevationangle,thesemixed-phasecloudscanwarmthesurfacethroughdownwardlongwaveradiation.Formoderate,thinmixed-phaseclouds,differenticewatercontentsinthemcanresultinupto9wattspersquaremetermoredownwardlongwaveradiationreachingthesurface.ThisindicatesapotentialsignificantaerosolindirectradiativeeffectinArcticmixed-phasecloudsbychangingice-phaseproperties.
(References:Zhao,M.2011.“Thearcticcloudsfrommodelsimulationsandlong-termobservationsatBarrow,Alaska.”PhDDissertation,UniversityofWyoming.
Zhao,M,andZWang.2010.“ComparisonofArcticcloudsbetweenEuropeanCenterforMedium-RangeWeatherForecastssimulationsandAtmosphericRadiationMeasurementClimateResearchFacilitylong-termobservationsattheNorthSlopeofAlaskaBarrowsite.”Journal of Geophysical Research115:D23202,doi:10.1029/2010JD014285.)
ARM Data Reveal the Strongest Long-Term Net Impact of Aerosols on Clouds and Precipitation
Aerosols—tinyparticlesintheair,likedustorsoot—canaffectcloudsandprecipitationbyservingascloudcondensationnuclei(CCN).Theycanaltercloudmicrophysicsandprecipitationprocessesandmodulateradiativeandlatentenergytochangeatmosphericdynamicsandthermodynamicsthatdictateclouddevelopment.Theseeffectscaneithersuppressorfostercloudandprecipitationprocesses.Variouseffectshavebeenstudiedforindividualcasesunderhighlyconstrainedconditions,butlittlehasbeendonetodecipherlong-termeffectsundergeneralconditions.
Long-term data show the spring season has distinct ice-liquid mass partition in Arctic mixed-phase clouds.
ARM Climate Research Facility ANNUAL REPORT – 2011
Usinga10-yeardatasetofextensivemeasurementsfromSGP,thelong-termnetimpactofaerosolsoncloudandrainfallfrequencyisrevealedforthefirsttime,andvariouseffectsaresortedoutunderdifferentmeteorologicalandcloudconditions.Cloud-topheightandthicknessarefoundtoincrease—mostsignificantlyinsummer—withincreasedaerosolconcentrationmeasurednearthegroundforcloudswithwarmbase(above15°C)andmixed-phasetops(below-4°C).Fewchangesarefoundforcloudswithnoiceorwithhighcloudbases.Theprecipitationfrequencyincreaseswithaerosolsfordeepcloudsofhighliquidwatercontentanddecreasesforcloudswithlittlewater.Theobservations,successfullyreproducedwithacloud-resolvingmodel,havesignificantimplicationstounderstandinganthropogenicinfluencesonwaterresources,monitoringEarth’sclimatechanges,andsustainingeconomicdevelopment.ThedrasticchangesincloudverticaldevelopmentcanalterEarth’sradiationbalanceandatmosphericdynamics.Becauseeconomicdevelopmentoftenisaccompaniedbyincreasesinaerosolemissions,thefindingsimplyasevereadverseimpactonsustainabledevelopment,especiallyoverregionsvulnerabletoextrememeteorologicalevents(e.g.,droughtorflooding).Increasesinaerosolorpollutiontendtopolarize
precipitation,makingdryplacesdrierandmoistregionswetter,reducingwaterusageefficiency—akeyfactorforsustaininglifeandagriculture.
(Reference:Li,Z,FNiu,JFan,YLiu,DRosenfeld,andYDing.2011.“Long-termoverallimpactofaerosolsontheverticaldevelopmentofcloudsandprecipitation.”Nature Geoscience:doi:10.1038/NGEO1313.)
Looking for Aerosol in All the Right Places
Globalclimatemodelscalculateatmosphericprocessesatscalescloseto100by100kilometers(62milesacross).Aerosols,tinyparticlesofdustorpollutionintheatmosphere,actonmuchsmallerscalesandcanvaryaccordingtolocalatmosphericorgeographicfeatures.Overlookingthesmall-scaleeffectsofaerosolscanhaveanegativeimpactonglobalclimatepredictions.Duringatwo-weekperiodoverMexicoCity,researchersfoundthatthedifferencebetweentheirdetailedaerosolmodelingandthecoarsemodelingusedinmodernglobalclimatemodelswasashighas30percent.Inglobalclimatemodels,theclimateeffectsofthesefeaturesareoftenaveragedoutoverthelarge-scalegrid,distortingtheactualeffectsoftheprocesses.Aerosols,whichscatterandabsorbsunlight,areknowntotiptheenergybalancetowardheatingorcooling,dependingonthetypeofparticleanditselevationaboveEarth’ssurface.Theresearchersidentifiedsmall-scaleprocessesthatcanleadtolarger,accumulatederrorsovertime.Usinga
high-resolutionatmosphericmeteorologyandaerosolmodelcombinedwithextensiveobservationsofaerosolandthesurroundingenvironment,theyfoundthatcertainaerosolemissionsarelikelytocauseerrorduetosmall-scalefluctuationsinatmosphericconditions.Thisstudyprovidesclimatescientistswithamoreaccurateaccountofaerosolsonthesmallscaletohelpanalyzeandpredictglobalclimatechanges.
(Reference:GustafsonJr.,WI,YQian,andJDFast.2011.“DownscalingaerosolsandtheimpactofneglectedsubgridprocessesondirectaerosolradiativeforcingforarepresentativeGCMgridspacing.”Journal of Geophysical Research–Atmospheres116:D13303,doi:10.1029/2010JD015480.)
Changes of cloud top temperature (a) and precipitation frequency (b) with aerosol number concentration (CN) measured at SGP for 10 years. Clouds are differentiated by cloud top temperature (CTT), bottom temperature (CBT), and rainfall amount.
High-resolution simulation for Mexico City (top), shows a more detailed and accurate picture of aerosol pollution compared to representations of a global climate model (bottom). The deep red to light green represents high to low concentrations of aerosol pollution.
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Characterizing Clouds at Arctic Atmospheric Observatories
TobetterobservetherolecloudsplayinArcticatmosphericradiationandhydrologiccycles,researchscientistsassembledcloudobservationsmadeoverthepastdecadeatsixArcticatmosphericobservatories—BarrowandAtqasuk(Alaska),Eureka(Canada),NyAlesund(Norway),Summit(Greenland),andtheBeaufortSea—toinvestigatemanybasiccloudcharacteristics,includingoccurrencefraction,verticaldistribution,persistenceintime,diurnalcycle,boundarystatistics,andphasedistributions.
Continuousground-basedobservations,providedviaacombinationofground-basedcloudlidar,radar,ceilometer,interferometer,microwaveradiometer,and/orradiosondesatthesites,revealannualcloudoccurrencefractionsrangingfrom58to83percent,withclearannualcyclevariabilitywherecloudsareleastfrequentinwinterandmostfrequentinlatesummerandfall(exceptinEureka).Importantly,thisstudyhasalsoprovidedabroaderexaminationofArcticcloudphase,monthlyaveragetotalcloudinessatindividuallocations,mediancloudpersistence,interannualvariability,andcloudphasedistributionsasafunctionofatmospherictemperatureandrelativehumidity.Significantinter-sitedifferencesdooccurinboththefrequencyofoccurrenceforcloudsofdifferentphasesandtheirannualvariability,suggestingthattheprocessesresponsibleforcloudformationandphasedeterminationaresimilaracrosstheArcticwhilelarger-scalemeteorologydeterminestheactualdistributionofcloudsandcloudphaseateachspecificlocation.ThesedataareimportanttobothbetterunderstandandsimulateinnumericalmodelstomoreaccuratelypredicttrendsinArcticclimate.
(References:Shupe,MD,VPWalden,EEloranta,TUttal,JRCampbell,SMStarkweather,andMShiobara.2011.“CloudsatArcticatmosphericobservatories,partI:Occurrenceandmacrophysicalproperties.”Journal of Applied Meteorology and Climatology50(3):626–644,doi:10.1175/2010JAMC2467.1.
ShupeMD.2011.“CloudsatArcticatmosphericobservatories,partII:Thermodynamicphasecharacteristics.”Journal of Applied Meteorology and Climatology50(3):645–661,doi:10.1175/2010JAMC2468.1.)
(a) Annual cycles of monthly mean cloud occurrence fraction at six Arctic atmospheric observatories. The average cloud fraction for all sites, equally weighting each site, is given as the black curve with annual averages provided (at right). For comparison, past Arctic cloud fraction climatologies also are provided. Monthly average vertical distributions of cloud occurrence fraction are provided for (b) Barrow, (c) SHEBA, and (d) Eureka.
Developer of the Millimeter Cloud Radar Recognized at the ASR Fall Meeting.DuringtheAtmosphericSystemResearchFallWorkingGroupMeetinginOctober,Dr.KennethMoran,NationalOceanicandAtmosphericAdministration(NOAA),waspresentedwithaplaqueinrecognitionofhis15yearsofoutstandingcontributionstotheARMProgramandARMClimateResearchFacility.AsthedeveloperoftheMMCR,Ken’sexpertiseandprofessionalism,aswellashissubsequentsupportandmaintenanceefforts,havebeeninvaluabletoARM’ssuccess.
ARM Technical Director Jim Mather (left) and ARM Radar Group Lead Kevin Widener (right) present a plaque to Kenneth Moran.
ARM Climate Research Facility ANNUAL REPORT – 2011
Anvil Clouds of Tropical Mesoscale Convective Systems in Monsoon Regions
Inthetropics,upper-levelcloudscontainingiceandmixturesoficeandliquidwaterstronglyaffectthetransferofradiationthroughtheatmosphereandareassociatedwithdeepconvection.Deepmesoscaleconvectivesystems(MCSs),largerthan~100kilometers,oftendeveloplargestratiformprecipitationregionsandaccountforalargefractionoftropicalprecipitation,anvils,andcirrusclouds;producemostofthelatentheatinginthetropics;andaffectradiativeheating.Thisstudy,whichanalyzedthreelocations:theMaritimeContinent,BayofBengal,andWestAfrica,constructsajointclimatologyofbothprecipitationstructureandanvilcharacteristicsoftropicalMCSstoanalyzetheireffectonradiativeheatinginthetropics.
TheMCSprecipitationstructureswereexaminedusingdatafromtheTropicalRainfallMeasuringMission’s(TRMM)PrecipitationRadar.CloudSatCloudProfilingRadarwasusedfortheanvilcloudstructuresandwasverifiedagainsttheARMverticallypointingcloudradars(NiameyandDarwin)withahighdegreeofconsistency.Theprecipitationstructureswerepartitionedintoconvectiveandstratiformprofiles,andanvilcloudsweresubdividedbythickness.ThedataweredisplayedusingContouredFrequencybyAltitudeDiagrams(CFADs).
Ingeneral,theanvilsgeneratedbyMCSsineachlocationhavesimilarstatistics,althoughtheyaredominatedbymeasurementsoftheextensivethinportionsofMCSanvils.Mostofthevariationinanvilstructureisevidentinthethickportions.TheWestAfricathickanvilsCFAD,indicatingabroad,flatreflectivityhistogramandmaximumreflectivitylowerintheanvils,contrastswiththeBayofBengalthickanvilsCFADthatshowsasharplypeakeddistributionofreflectivityatallaltitudeswithmodalvaluesincreasingdownwardmonotonically.TheMaritimeContinentthickanvilsreflectivityhistogramisintermediatebetweentheothertwo.Theobserveddifferencesbetweenthecontinentalandoceanicanvilstatisticsimplythatfutureparameterizationsandrepresentationsofanvilcloudsinpredictionmodelsmustaccountfordifferentanvilphysicsinthetworegions.
(Reference:Cetrone,J,andRAHouzeJr.2009.“Anvilcloudsoftropicalmesoscaleconvectivesystemsinmonsoonregions.”Quarterly Journal of the Royal Meteorological Society 135(639):305–317,doi:10.1002/qj.389.)
These contour diagrams show the frequency distribution of CloudSat cloud profiling radar reflectivity as a function of height of thick (>6 kilometers) mesoscale convective system anvils over (a) West Africa, (b) the Maritime Continent, and (c) Bay of Bengal. The contours show bin counts divided by total counts. The contour interval is 0.001, contour values range from 0.001 to 0.018, and bin dimensions are 5 dBZ by 250.
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Infrastructure AchievementsMaintainingmultipleinstrumentedsitesaroundtheworldisnoeasyfeat.TheARMFacilityusesateamofscience,engineering,andtechnicalpersonneltoensureeffectiveoperations,keepupwithtechnologydevelopments,deliverhigh-qualitydata,andprovideoutreachtoaglobalaudience.
Recovery Act
DopplerLidarsMeasureWindinThreeDimensions
ThroughtheRecoveryAct,ARMaddedthreenewDopplerlidarsystemstoitsmeasurementsuite.TheDopplerlidaroperatesinasimilarfashionasaradar;pulsesofenergyaretransmittedintotheatmosphere,andtheenergythatreturnstothetransceiveriscollectedandmeasured.BydetectingtheDopplershiftinthereturnedenergy,theDopplerlidarproducesheight-andtime-resolvedmeasurementsofverticalairvelocityinthelowertroposphere.Inaddition,thenewARMDopplerlidarshavefullupper-hemisphericalscanningcapabilities.Thisenables3Dmappingofturbulencestructureandmeasurementofhorizontalwindprofiles.ThelidarsweretestedattheSGPsitebeginninginOctober2010.Followingthetestperiod,twoofthenewDopplerlidarsweredeployedatSGPandTWPDarwin,whileonesystemiscurrentlydeployedinIndiaandwilltravelwithAMF1.
AGiantLiftforArcticClimateData
UsheringinthefirstoperationalprecipitationradarontheU.S.ArcticCoast,engineerscompletedacceptancetestingforthenewX-SAPRonJune21,2011,atitslocationatoptheBarrowArcticResearchCenterinAlaska.DatafromtheradararetransmittedthroughawirelessconnectiontotheARMsitedatasystem.Withtheradarupandrunning,signalreturnsonJune24,2011,providedanindicationoftheradar’scoverageovertheNorthSlope,reachingdistancesof200–250kilometerstothenorthofBarrowovertheArcticOcean.
The“X-band”referstothe9.5-gigahertzfrequencyatwhichtheradaroperates.Differentfrequenciesdetectdifferenttypesofcloudparticlesandalsodeterminehowfartheradarcandetectthoseparticles.TheX-bandradarissensitivetoprecipitatingparticles,andinthesnowandlightraincommoninBarrow,itcan“see”theseprecipitatingsystemstogreatranges.Thisdual-polarizationDopplerradarprovidesdetailsaboutprecipitationthatallowscientiststomoreaccuratelyestimaterainfall,classifyprecipitationtypes(rain,sleet,snow)andmapwindfields.
A newly installed X-SAPR operates from atop the Barrow Arctic Research Center in Alaska.
Two of the three new Doppler lidars are shown here during testing at SGP in October 2010.
ARM Climate Research Facility ANNUAL REPORT – 2011
NewRamanLidarProvidesTropicalRemoteSensingData
ThefirstoperationalRamanlidarinthetropicsbegangatheringdataattheTWPDarwinsiteinNovember2010.Nearlyidenticaltothelong-runningRamanlidaratSGP,itistheonlyactiveremotesensinginstrumentattheDarwinsitecapableofprovidingsimultaneousmeasurementsofwatervapor,clouds,andaerosols.Itprovidesausefulcomplementtodatacollectedbytheotherinstrumentsatthesite.
TheRamanlidar(lightdetectionandranging)usespulsesoflaserradiationtoprobetheatmosphere.Atelescopecollectsthebackscatteredradiationthatreturns,andtheopticsinsidethelaboratoryshelterusethatradiationtoderivetime-andaltitude-resolvedprofilesofatmosphericwatervapor,aerosols,clouds,andtemperature.Thesystemishousedintwostandaloneshelters;oneservesasalaboratoryenclosure,andtheothercontainssupportsystemssuchasHVACservicesandpowerconditioning.
Site Operations
NewAircraftProbesinOperationAgain
InApril,researchersbegantheMC3EfieldcampaignatSGP.Aspartoftheairborneresearchportionofthecampaign,NASAsponsoredtheUNDCitationaircraftthatprovidedinsituobservationsofprecipitation-sizedparticles,icefreezingnuclei,andaerosolconcentrations.JoiningtheCitation’sinstrumentpayloadforthecampaignweretwonewaircraftprobes—anairborneultra-highsensitivityaerosolspectrometer(UHSAS-A)anda“version3”high-volumeprecipitationspectrometer(HVPS-3)—purchasedin2010bytheARMFacilitythroughtheRecoveryAct.BothprobescompletedresearchflightsonaGulfstream-1(G-1)aircraftforthefive-weekCalwatercampaigninCalifornia.
TheUHSAS-Ahasincreasedresolutionformeasuringawiderrangeofaerosolsizedistributionsandconcentrationsthanotherinstrumentsofasimilarnature.Meanwhile,theHVPS-3measuresthenumberandsizeofprecipitationparticlesandprovidescompletedigitalimagesofprecipitationparticlesuptonearlytwocentimetersinsize.Inaddition,theHVPS-3’snewslantedprobetipdesignandpost-processingtechniquesareexpectedtoresultinmorerepresentativeparticlesizedistributionsoftheiceinthethunderstormanvilsandwithinprecipitatingclouds,asdatacollectedwitholderprobeshavebeenquestionedduetotheinfluenceof“shattering.”
In March, ARM Aerial Facility scientist Jason Tomlinson met with colleagues at the University of North Dakota to assist in the integration of the probes onto the Citation aircraft and to provide training on the operation of the UHSAS-A (back) and HVPS-3 (front) instruments.
The new Raman lidar in Darwin is nearly identical to the lidar that has been in operation at SGP since 1996.
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ARMComputingClusterAcceleratesLarge-ScaleDataProducts
ThreenewsystemscurrentlybeingimplementedattheARMDataArchivewillprovidedataprocessing,analysis,andvisualizationcapabilitiesforusers.TheARMAnalysisandVisualizationSystemwillcontaindatavisualizationtoolsforvariousvisualizationandsmall-scaledataextractiontasks,allowinguserstointeractwiththelarge-volumedataproductsgatheredbyARMradarsandlidars.Thesystemwillalsobeusedtoproducepre-computedplotsforlargevolumesofscanningdata,aswellasforsoftwaredevelopmentandevaluation.
TheARMLarge-ScaleDataProcessingsystemwillexpeditethecreationandevaluationofdataproductsfromnewlargedatastreams.Aspecializedgraphicsprocessingunit-basedsystemwillalsobeimplemented,allowingintensivecomputationforverticalvelocitymeasurements.Dataoutputfromthesesystemswillbearchivedonalong-termbasisanddistributedtousersthroughtheARMDataArchive.
Data Delivery
Long-Term,Large-ScaleEnsembleForcingDataSetfor DarwinAvailable
AnewdatasetisavailablefortheARMTWPDarwinsiteforlong-term,large-scaleforcingdata.ThesedatawereconstrainedwithC-POLradarretrievedrainfallthroughthevariationalanalysismethod(ZhangandLin1997)byusingtheEuropeanCentreforMedium-RangeWeatherForecasts(ECMWF)analysis.Thisisanensembleforcingdataset(currentlyN=100),whichwasproducedbyconsideringpotentialerrorsinradar-retrievedrainfallestimate,andcoversthreewetseasonsfrom2004to2007.
MoreClimateModelingBestEstimateDataAvailableforMoreSites
InOctober2010,thelatestreleaseoftheClimateModelingBestEstimate(CMBE)datasetaddedsoundingsandsurfacemeteorologicalmeasurementsintheCMBE-ATMdatastreamforBarrow,Alaska,andallthreeTWPsites.Forthesefoursites,thecloudandradiationdatastream,orCMBE-CLDRAD,nowincludesthemostcurrentavailablesourcedata.Inaddition,CMBE-CLDRADhasthemostrecentreleaseofintegratedliquidwaterandwatervapordatafromthemicrowaveradiometer(MWRRET)dataset,whichwasreprocessedforallsitessincethelastCMBErelease.
AlsoprovidedisthestatisticalsummaryoftheCMBEdataforthesefourARMsites.ItincludesbothmonthlymeanandmonthlymeandiurnalcycleandtheirclimatologiesforallthegeophysicalquantitiescontainedintheCMBEdatasets.Formostsites,themostcurrentdataarefrom2010.
Soundings and surface meteorological measurements are now available for five ARM sites in the CMBE data set.
The lower panel shows 100 precipitation time-series derived given potential errors in radar-retrieved rainfall estimate. The upper panel shows the profile of vertical velocity derived using a best-estimate precipitation time-series. Strong rainfall is clearly associated with strong vertical motion in the mid- and upper-levels.
The top plot shows data gathered from a C-SAPR at SGP, and the bottom plot displays a “moment” from that data mapped to a Cartesian grid. These plots were generated using the ARM Analysis and Visualization system, taking about 20 hours and using 8 processors.
ARM Climate Research Facility ANNUAL REPORT – 2011
OverhaulofDataSystemStatusViewerHitsBull’s-eye
Howdoyoudisplaytheoperationalstatusofnearly200instrumentsatmultiplesitesaroundtheworldonasinglewebpage?InlateJune,ARMimplementedamajorsystemoverhauloftheDataSystemStatusViewer,orDSView—theinteractivedatabaseprovidingoperationalstatusinformationforeveryinstrumentatARM’spermanentsites.NowrunningwithAdobe®Flash®software,thecomplexgridissurprisinglyeasytonavigate.Usinga“bulls-eye”toguidetheviewertothedesiredinstrumentandsite,thenewdisplayalsoincludesoptionsforfilteringinformation,browsingprocessinglogs,andexportingstatusreportstoExcelformat.
ThelatestinstallmentofDSViewhasatotallydifferentlookandfeelthanpreviousversions,ismuchfaster,andiseasilydeployedandinstalled—eachsitehasitsownDSViewwebpagedisplayingonlysite-relevantinformation.Becausecollection,timecheck,andingestprocessesrunonboththesiteandDMFsystems,thisallowsforquickandhelpfulcomparisons.Inupdatingthegridtoanintegratedprocess/dataview,thedisplayisrefreshedeveryfiveminuteswhilecontentinthedatabasehistoryisusedtodisplayatimelineviewofcumulativechangestodetectintermittentevents.
NewDataEvaluationProducts
InordertoensurethatVAPsmeetthehighqualitystandardsoftheARMDataArchive,newproductsprogressthroughan“evaluation”stagebeforetheirfinalrelease.InFY2011,twonewproductsfocusingoncloudpropertiesandradiationmovedtotheevaluationstage.
TheARMCloudRetrievalEnsembleDataSet(ACRED)providesaroughestimateoftheuncertaintiesincurrentretrievedcloudmicrophysicalpropertiesforclimatemodelevaluationanddevelopment.Itwascreatedbyassemblingnumerousexistingground-basedcloudretrievalsfromtheARMFacility’spermanentresearchsites.
OneyearofdatagatheredatSGPisavailableintheRadiativelyImportantParametersBestEstimate(RIPBE)VAP.Thisproductcontainsacompletesetofradiativelyimportantparametersassembledfromvariousinstrumentsonauniformverticalandtemporalgridwithqualitycontrolandsourceinformation.
ThreeDataProductsReleasedforWidespreadUse
Threedataproductsmovedfrom“evaluation”to“operational”status,releasingthedatatotheARMDataArchiveforusebythescientificcommunity.TheSurfaceSpectralAlbedo(SURFSPECALB)VAPcreatesanear-continuousbestestimateofbroadbandandnarrowbanddownwellingirradiance,upwellingirradiances,andsurfacealbedousingthemultifilterradiometers(MFRs)onthe10-meterand60-metertowersandthemultifilterrotatingshadowbandradiometers(MFRSRs)attheSGPCentralFacility.TheVAPidentifiesthedominantobservedsurfacetypeforeachdayateachtowerandthenextrapolatesthe6-channelnarrowband
The upper panel shows the output aerosol extinction field in RIPBE, and the bottom panel shows the quality control (qc) flags on aerosol extinction. Descriptions of the qc flags are given in the netCDF file header. In this case, the gold and pink qc flags on the aerosol extinction indicate periods at the top of the aerosol profile where data were missing in the input file. These data points are marked as indeterminate, and RIPBE either interpolates over the missing data (gold) or uses the closest good value (pink).
This partial window of DSView shows filtering options for various ARM sites on the left. The bull’s-eye can be dragged to any spot in the matrix to highlight a specific site/instrument.
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This sample data plot from MPLCMASK provides several cloud measurements gathered by the MPL.
MFRalbedovaluestohighspectralresolutionatone-minutetemporalresolution.DataareavailableforSGPfromJanuary2004onwards.
TheMicropulseLidarCloudMask(MPLCMASK)VAPprovidescloudbaseheight,cloudtopheight,andbackscattercoefficientfornon-polarizedmicropulselidarmeasurements.Inaddition,depolarizationratioiscomputedforpolarizedandfast-switchingmicropulselidarsystems.ThisVAPprocessesdatafortheSGP,NSA,TWP,andAMFsites.
Finally,theMicrowaveRadiometerRetrievals(MWRRET)VAPhasdataavailablefortheSGP,NSA,andTWPsites,aswellastheBlackForest,Germany,deploymentoftheAMF.AdditionalAMFdeploymentswillbeprocessedinthenextyear.TheMWRRETVAPretrievescolumnprecipitablewatervapor(PWV)andliquidwaterpath(LWP)fromthe2-channelmicrowaveradiometersusingaphysicalretrievalmethodologythatprovidesimprovedretrievalsoverthestandardstatisticalcoefficientmethod.
Communication, Education, and Outreach
ARMJoinsUserFacilityDisplayatCapitolHillExhibition
TobecomebetterinformedabouttheresearchconductedatDOEuserfacilities,membersofCongressextendedaninvitationforthefacilitiestotakepartinascienceexhibitiononCapitolHillonApril7,2011.Asoneofabout40userfacilitiesparticipatingintheexhibition,ARMprovidedcontentforaposterdisplayintheRayburnHouseOfficeBuildingandwasrepresentedattheeventbyJimmyVoyles,ARMChiefOperatingOfficer.Severalcongressmen,staffers,andDOEandnationallaboratorymanagersstoppedbytheARMFacilityposter,whichprovidedanoverviewandimagesofkeyfeaturesoftheFacility,includingsites,instruments,data,outreach,demographics,andpublications.VoylesansweredavarietyofquestionsaboutARM’sdataproducts,collaborations,andcontributionstoclimateresearchadvances.Thepostersessionwasfollowedbyaninformalreceptionwithshortkeynoteaddressesbyinvitedspeakers.
ARMDataFeaturedatUnitedNationsClimate ChangeConference
AttheUnitedNationsClimateChangeConference(COP16)inCancun,Mexico,inearlyDecember2010,anewglobalaudiencegotthechancetolearnaboutARMandhowitsdataareusedtoimproveclimatemodels.LedbytheU.S.DepartmentofState,ARMwaspartofaninteragencymultimediademonstrationaboutU.S.climateresearcheffortsthatwaspresentednumeroustimesthroughouttheconference.
AlongwithNASAandNOAA,DOEprovidedinformationanddatathatwereintegratedintotheStormCenterCommunications,Inc.(SSC)Envirocast®Vision™TouchTablesystem.Consistingofacenterconsolewithaplasmascreenoneachsidetodisplaysupportingvideosandanimations,thesystemallowsuserstoaccess,visualize,andinteractwiththesciencedatainreal-timeusingtouchscreentechnologyandGoogleEarth™.
User facility representatives gather in the foyer of the Rayburn House Office Building to set up their posters for the user facility science exhibition held on April 7, 2011.
Attendees at COP16 gathered in the U.S. Center’s “living room” to learn more about climate change research among the federal agencies. (Photo courtesy of the U.S. Department of State.)
ARM Climate Research Facility ANNUAL REPORT – 2011
TheengagingmultimediaexperienceintheU.S.Center“livingroom”resultedinverypositivefeedbackfromtheaudience,includingmembersofofficialdelegationsandnon-governmentalorganizations.MembersoftheStateDepartmentindicatedthattheUnitedStateswaspresentedexactlyhowtheyenvisioned:anationthatcaresaboutclimatechangeandthatisactingtolearnmore,whileusingthebestsciencetoadapttothechangesthatareoccurring,mitigatewherepossible,andofferassistancetoothernationsthataskforit.
ARMExploresNewFrontierwithAmericanAssociationforthe AdvancementofScience
Reachinganewaudience,theARMFacilityparticipatedforthefirsttimeintheannualmeetingoftheAmericanAssociationfortheAdvancementofScience(AAAS)heldFebruary17–21,2011,inWashingtonD.C.Atotalof8,200meetingregistrants,families,andpressattendedtheevent,themed“ScienceWithoutBorders”toemphasizetheglobalscaleofcomplexscientificchallenges.
UnliketheotherscientificconferencesthatARMtraditionallyattends,AAAShelditspublic“FamilyScienceDays”inthesamehallasthescientificexhibitsandposters.TheresultingcrossflowoftrafficledmanyteacherstotheARMexhibit.OneteacherexpressedinterestinusingARM’slivedatadisplayinherclassroomasanexampleforcommunicatingdata,andseveralscienceteachersaskedaboutusingARMdataforclassroomprojects.Inall,justover200visitorsstoppedattheARMexhibittotalkorpickupmaterialsduringtheevent.About300visitorsstoppedbytheARMeducationexhibit,wherethelessonplanswerewellreceived,andseveralvisitorssigneduptoreceivethebiannualeducationnewsletter.
ProfessorPolarBearGoestoWashington
OnOctober23–24,2010,ARMparticipatedintheU.S.DepartmentofEnergy’sexhibitattheUSAScienceandEngineeringFestivalontheNationalMallinWashingtonD.C.ThenewClimateKidcutoutwasabighit,withchildrenandadultsalikestoppingtotakepictureswithitandProfessorPolarBear.ARMEducationbookmarks,activitybooklets,andlessonplanswerehandedout.AcomputershoweddatafromoneyearagoatARM’spermanentandmobilesites,withexplanationsofwhatmeasurementseachdataplotshowed.AlightmeterandlampsimulatedwhathappenswhencloudspassbetweentheEarthandthesun,andawindmetertrackedthewindspeedandplotteditonachart.
Thetwo-dayeventwastheculminationofatwo-weekfestival,includingeventsinWashingtonD.C.andacrossthecountry.Morethan350organizationsparticipatedintheFestival,includingacademicinstitutions,researchinstitutes,governmentagencies,technologycompanies,museums,andcommunityorganizations.Asmanyas1millionvisitorshavebeenreportedasattending.
Numerous scientists and educators at the AAAS 2011 Annual Meeting stopped at the ARM exhibit to learn about the user facility’s measurement capabilities and data collections.
One of ARM’s Climate Kids debuted at the USA Science & Engineering Festival. Photo courtesy of the Festival.
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Field CampaignSUMMARY
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ARM Climate Research Facility ANNUAL REPORT – 2011
Dates Campaign Name Status Description
ARM Aerial Facility
October2010–September2012
AirborneOpenPolar/ImagingNephelometerforIceParticlesinCirrusCloudsandAerosols
InProgress Aprovenlaboratoryinstrumentwasmodifiedforairborneapplicationsthatwillmeasurephasefunctionoficecrystalsandaerosolparticleswithoutinlettubes.ThisO-I-Neph(OpenImagingNephelometer)willmakethefirsttrueinsituobservationsofcirruscloudphasefunctionandcontributetocharacterizationofaerosolparticlepropertiesandremotesensingvalidationstudies.Theinstrumentdesignusesanarrow-beamlasersourceandawidefield-of-viewimagingcameratocapturetheentirescatteringphasefunctioninoneimagealmostinstantaneously.Thelaboratoryinstrument’ssensitivityallowsfullyresolvedphasefunctionsofgasmolecules(Rayleighscattering)andlowconcentrationbackgroundaerosolparticles.
October2010–July2012
TheMaturationandHardeningoftheStabilizedRadiometerPlatforms
InProgress Measurementsofsolarandinfraredirradiancebyinstrumentsrigidlymountedtoanaircrafthavehistoricallybeenplaguedbytheintroductionofoffsetsandfluctuationsintothedatathatareduesolelytothepitchandrollmovementsoftheaircraft.TwoStabilizedRadiometerPlatforms(STRAPs)weredevelopedtoaddressthisproblem.AspartofthematurationandhardeningoftheexistingSTRAPinstruments,upgradesweremadetothenavigationalcomputerhardwarecomponents,theplatformcontrolsoftware,andtheoperatingsystemofeachoftheSTRAPs.
October2010–December2011
FurtherDevelopmentoftheHOLODEC2(HolographicDetectorforClouds2)Instrument
InProgress TheHOLODEC2instrumentmeasuresiceandcloudparticleshape,size,and3Dpositionviadigitalinlineholography.Thesamplevolumeisnotdependentonparticlesizeorairspeed,butislargeenoughthatsizedistributionsforclouddropletsandsmalliceparticlescanbeobtainedfromsingleholograms.ThiscampaignwillhardentheHOLODEC2instrumenttoprepareitforregularuseinfieldcampaignsthroughthreemajoractivities:(1)design,configure,andtestanewdatasystemforHOLODEC2capableofreliablyrecordingandstoringdatarecordedinatypicalfullfieldcampaign,(2)furtherdevelopthehologramprocessingcodebydevelopingtoolstoallowtheusertomoreeasilyselectparametersforhologramprocessingandascertainthequalityoftheresults,and(3)refineorreengineerthesubsystemsoftheinstrumentasrequiredfromtheinitialtestflightsresultstomakeitfitforregularfieldcampaignwork.
October2010–September2011
AircraftIntegrationandFlightTestingof4STAR
Completed Thegoalofthisresearcheffortwastodevelopanddemonstrateanairbornesun-skyspectroradiometertoprovideinformationonaerosols,clouds,andtracegasesextendingbeyondwhatcanbederivedfromexistingairbornesunphotometersandtoimprovecompactness,modularity,andversatility.TheproposedenhancedinstrumentwasanairborneSpectrometerforSky-Scanning,Sun-TrackingAtmosphericResearch(4STAR-Air)basedonthegroundprototype(4STAR-Ground)thathasbeendevelopedandextensivelytestedoverthepastseveralyears.Theintegrationeffortofthe4STARandG-1aircraftincludedmechanicalaccommodationaswellaselectricalanddatacommunicationdetails.
TheARMFacilityroutinelyhostsfieldcampaignsatallitssites,plusspecialdatacollectioneffortsandoff-sitecampaigns.Manyoftheseactivitiesspanseveralyears.ThefigurehereshowsthetotalnumberoffieldcampaignsandspecialdatasetcollectionsthatoccurredinFY2011,includingtheseongoingefforts.ThesubsequenttablesummarizesjustthosecampaignsthatbeganinFY2011.Formoreinformation,visittheFieldCampaignwebpageat
www.arm.gov/campaignsTotal 2011 Field Campaigns
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February2011–March2011
CalwaterFieldCampaign Completed ThegoalofthisprojectinvolveddetermininghowaerosolsimpactcloudsandprecipitationpatternsinCalifornia.Specifically,flightswereconductedthroughprecipitatingandnon-precipitatingcloudstodeterminewhethertherewerechemicalorphysicaldifferencesinthecloudnucleiformingtheclouds.Thesourcesofthekeycloudseedsweredeterminedusingsingle-particlemassspectrometry.Cloudphysicsandchemistrywereprobedinadditiontohighlevelmeteorologicaldata.Meteorologicaldatawereacquiredduringflightsaswellasatseveralground-levelsamplingsites.ThegoalwastounravelthekeyparametersleadingtohighlevelsofrainandsnowinCaliforniaversussustainedcloudcoverwithverylittleprecipitation.
March2011–April2011
MACPEX/SPARTICUSContinued
Completed Inaninvestigationofpropertiesofcirrusandcirrusanvils,afast-forwardscatteringspectrometerprobe(FFSSP)andafastclouddropletprobe(FCDP),installedontheSPECLearjet,flewincirruscloudsoverSGPinconjunctionwiththeNASAWB-57FintheMACPEXfieldcampaign.
ARM Mobile Facility
November2010–April2011
StormPeakLabCloudPropertyValidationExperiment(STORMVEX)
Completed StormPeakLab(SPL),locatedeastofSteamboatSprings,Colorado,isawell-establishedcloudandaerosolresearchfacilityoperatedbytheDesertResearchInstitute.SPLislocated3210metersabovesealevelandisabovecloudbase25percentofthetimeduringthewinterseason.ThealreadyextensiveinstrumentsuiteatSPLwasaugmentedwithadditionalstate-of-the-artinstrumentstypicallyusedforairbornecloudresearchbytheStrattonParkEngineeringCorporation(SPEC).SPLandSPECcollectedinsitucloudandprecipitationpropertymeasurementswhiletheAMF2operatedatalocationapproximately2.4kilometerswestand2,078metersinelevationduringthewinterseason.
June2011–March2012
GangesValleyAerosolExperiment(GVAX)
InProgress GVAXisusingtheAMFtomeasurerelevantradiative,cloud,convection,andaerosolopticalcharacteristicsovermainlandIndiaduringanextendedperiodofseveralmonths.Theaerosolsinthisregionhavecomplexsources,includingburningofcoal,biomass,andbiofuels;automobileemissions;anddust.TheextendedAMFdeploymentwillenablemeasurementsunderdifferentregimesoftheclimateandaerosolabundanceinthewetmonsoonperiodwithlowaerosolloading;inthedry,hotsummerwithaerosolsdispersedthroughouttheatmosphericcolumn;andinthecool,drywinterwithaerosolsmostlyconfinedtotheboundarylaterandmid-troposphere.
North Slope of Alaska
January2011–December2014
Cosmic-RayMoistureProbeonNorthSlopeofAlaska
InProgress Anewsoilmoisture/snowmonitoringinstrumentwasinstalledattheBarrowsiteintheArctic.Thisinstrumentdetectscosmic-rayneutronsasaproxyforsoilmoistureandsnowcover.Dependingupontheresultsachieved,thismayleadtoanetworkofprobesforinstallationintheArctic.
January2011–December2013
SeaIceEffectonArcticPrecipitation-Extension
InProgress Precipitationsamplesforeachstormthatbringsabout2millimeterswaterofrain(or2centimetersofsnow)arecollectedattheBarrowandAtqasuk,Alaska,sites.Foragivenstorm,coastalandinlandsitesoftenhaveadifferentmoisturemixfromsubtropicalversuslocalsources.Bylookingattheweatherpatternsthatareresponsibletoagivenstorm,scientistswillbeabletodeterminewhatpartoftheoceansurfacecontributestothemoisturebudgetofthestorm.Theresultswillbeinterpretedfortheindividualinfluencesoftheice-freeareaoftheArctic,ofstormtracks,ofatmospherictemperaturesatbothmoisturesourcesandprecipitationsites,andofcirculationchangesassociatedwiththeArcticOscillationand/ortheNorthAtlanticOscillation.
ARM Climate Research Facility ANNUAL REPORT – 2011
June2011–May2021
AtqasukGPSBaseStation InProgress AglobalpositioningsystembasestationinAtqasukprovidesalocalsourceofgeodeticqualitydifferentialcorrectionsforGPSdatapost-processingbyscientistsandothersoperatingintheAtqasukareaontheAlaskanNorthSlope.ThestationislocatedattheARMClimateResearchFacility,whichprovidessecurity,power,andEthernetcommunications.Thestationrunscontinuously,and15-secondsampleratedataarearchivedattheUniversityNavstarConsortium(UNAVCO)andavailabletothepublic.Alldataareavailableviatheinternet.
Off-Site Campaigns
February2011–November2014
FourCornersAerosolCloudClimateExperiment
InProgress FourCorners,NewMexico,isoneofthelargestpointsourcesofnitrogenoxidesintheUnitedStatesfromtwopowerplantsintheregion,inadditiontosulfates.Thiscreatesacidicaerosolsthataretransportedtodownwindregionswheretheyinteractwithorganicemissions(sesquiterpenes)frompineforestsinsouthernColorado.Thedeploymentwillbeusedtoobserveboundary-layerheightstoprovidethedynamicalcontextforasolartrackingFourierTransformSpectrometerthatwillmeasuregreenhousegases,aerosolprecursors,andradiationfieldsonaregionalscale(10–100kilometer).
May2011–May2012
915-MHzWindProfilerforCloudForecastingatBNL
InProgress Insupportoftheinstallationofa37megawattsolararrayonthegroundsofBrookhavenNationalLaboratory(BNL),astudyoftheimpactsofcloudsontheoutputofthesolararrayhasbeenundertaken.Emphasisisonpredictingthechangeinsurfacesolarradiationduetotheobserved/forecastcloudfieldonafive-minutetimescale.The915-MHzwindprofilerisbeingoperatedatBNLtoprovideinformationontheverticalprofileofwinds,especiallyprofilesinthelowertroposphere,asanadditionalinputtoshort-termcloudmodelingstudies.Asecondaryfocusisontheobservationofdynamicsandmicrophysicsofprecipitationduringcoldseason/winterstormsonLongIsland.
June2011–August2011
AerosolLifeCycleIOPatBNL
Completed AtBNL,intensiveaerosolobservationswereconductedusingtheMobileAerosolObservingSysteminaregionexposedtoanthropogenic,biogenic,andmarineemissionswithatmosphericprocessingtimesdependingonairmasstrajectoriesandtimeofday.
June2011–November2011
EvaluationandUpgradestoARMFFSSPandFCDP
InProgress BothFCDPandFFSSPprobeswereacquiredbyDOEundertheRecoveryActprocurementprogram.Theseareadvancedversionsofthefast-forwardscatteringprobe(FSSP)andclouddropletprobe(CDP).BoththeFCDPandFFSSPincorporatestate-of-the-artelectronicsthatprocessandrecordparticle-by-particlemeasurementsthatareusedtoremoveshatterediceparticles,coincidenceandadditionalstatisticalmeasurements.TheFCDPalsoincorporatesaslit-basedopticalsystemthatisdesignedtoreduceuncertaintiesinsamplevolumedetermination.
Southern Great Plains
December2010 IRCloudCameraFeasibilityStudy
Completed DuringDecember2010,aprototypelong-wavelengthinfraredcloudcamerasystemwasdeployedattheSGPGuestInstrumentFacility.Thesystemconsistedofamicrobolometercamera(~7–15meters)tocaptureskyimagery,ablackbodycalibrationsource,andaGPSreceiverusedtoestimateatmosphericcolumnwatervaporandconstrainatmosphericcompensation.Thecamerasystemcollectedcalibratedskyradianceimagesco-incidentwiththeSGPCentralFacilitywiththegoalofquantitativelyassessingitsabilitytodetectthincirrusclouds.
January2011 ARRAAERIComparison Completed TheARMFacility,usingRecoveryActfunds,acquiredanewAERIinstrumentfortheSGPsite.Thisnewinstrumentwasrunside-by-sidewiththeoperationalAERIattheSGPCentralFacilitytoevaluateitsaccuracyandnoiseperformance.
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March2011–April2011
MiddleLatitudeAirborneCirrusPropertiesExperiment(MACPEX)
Completed NASAWB57aircraftflewpatternsabovetheVanceceilingduringApril.Aircraftflightplansincludedsteppedhorizontallegsandspiralup/downincirrus.
March2011–February2012
PGSValidation2011 InProgress ApairedtreatmentcontrolexperimentcontinuesattheAgriculturalResearchServicesSouthernPlainsRangeResearchStation(SPRRS).Theongoingexperimentcomparesenergyandcarbonfluxesfromafieldrecentlyplantedtoswitchgrass(apotentialbiofuelcrop)withfluxesfromwinterwheat.TheongoingexperimentisbeingconductedinacollaborationthatincludesSPRRSstaffandresearchersfromtheUniversityofOklahoma.
March2011–February2012
RadonMixing(RAMIX2011–2012)
InProgress Thiscollectionofradonmixingratiodatafromthe60-metertowerhastheobjectiveofusingtheradonmeasurementstohelpestimateregionalcarbondioxide(andlatermethane)exchange.TheprojectisbeingconductedwithexistinginstrumentationalreadyoperationalatSGP.
March2011–March2012
ContinuousLightAbsorptionPhotometer(CLAP)
InProgress TheCLAPwillbeinstalledatSGPinFebruaryof2011.Duringaone-yearcomparisonperiod,aerosolabsorptioncoefficientsfromtheCLAP,particlesootabsorptionphotometer(PSAP),andphoto-acousticabsorptionphotometer(PAAS)willbecomparedandtheCLAPperformanceevaluated.AspartofGVAX,theCLAPwillalsobeinstalledattheAMFinparalleltothePSAP.TheinstallationinIndiawillgiveanopportunitytoevaluatetheCLAPandPSAPunderconditionsofhighorganicaerosolloading.
April2011–April2014
ReFresh InProgress TheReFreshinvestigationistakingplaceattwosites:SGPandtheCapeGrimsiteinTasmania,Australia.TheNASADC-8isflyingabovethetopsoftheweathersystems,providingcloudandrainfallprofilesfromacombinationofW-,Ka-andKu-bandradars.Asecond,lower-altitude,aircraft,theCIRPASTwinOtter,providesinsituprofilesofcloudmicrophysicalandaerosolmeasurements,icenucleiconcentrations,cloudchemistry,andwaterisotopiccompositioninthelowercloudregions.
April2011–June2011
MidlatitudeContinentalConvectiveCloudsExperiment(MC3E)
Completed ThisjointfieldcampaigninvolvingNASAGlobalPrecipitationMeasurementProgramandASRinvestigatorswasconductedinsouth-centralOklahoma.TheexperimentleveragedtheunprecedentedobservinginfrastructureavailableinthecentralUnitedStates,combinedwithanextensivesoundingarray.Thegoalwastoprovidethemostcompletecharacterizationofconvectivecloudsystemsandtheirenvironmentthathadeverbeenobtained,providingconstraintsformodelcumulusparameterizationsthathadneverbeforebeenavailable.Severaldifferentcomponentsofconvectiveprocessestangibletotheconvectiveparameterizationproblemweretargeted,suchaspre-convectiveenvironmentandconvectiveinitiation,updraft/downdraftdynamics,condensatetransportanddetrainment,precipitationandcloudmicrophysics,influenceontheenvironmentandradiation,andadetaileddescriptionofthelarge-scaleforcing.
May2011–June2011
MiddleLatitudeAirborneCirrusPropertiesExperiment(MACPEX)Continued
Completed AsacontinuationoftheMiddleLatitudeAirborneCirrusPropertiesExperiment(MACPEX),theNASAWB57aircraftwasflowninpatternsabovetheVanceceiling.Aircraftflightplansincludedsteppedhorizontallegsandspiralup/downincirrus.
May2011–October2011
FieldTestofaHighDynamicRangeSkyImagingSystem
InProgress TheHighDynamicRangeSkyImagingSystem(HDR-SIS)willbedeployedattheSGPCentralFacilityfora4-monthperiod.TheHDR-SISisaninnovativedigitalimagerandcontrolsystemdesignedforimprovedimagingofatmosphericconditionsandradianceacrossthefullskydome(includingtheexposedsolardisk)withoutradiometricsaturationorlossofinformationassociatedwithuseofashadingdevice.InitialtestsoftheHDR-SIShavebeenhighlysuccessfulandsuggestpromiseforapplicationstoquantitativestudiesofclouds,aerosolsandradiation.Thisfieldcampaignisdesignedtoevaluatethispotential.
ARM Climate Research Facility ANNUAL REPORT – 2011
June2011–August2011
HumidityExperiment—Infrared(HUMEX-I)
Completed ThisexperimentdeployedtwoAERIsatSGPattwoofthethreeX-bandradarsitesforanextendedperiodoftimetohelpcharacterizethehorizontalinhomogeneitiesinthewatervaporfieldovertheSGPdomain.Thesedatawillbeusedtocharacterizetheverticalandhorizontaldistributionofwatervaporintheboundarylayer,especiallyforpre-convectiveenvironments,tobetterunderstandtheconnectionbetweeninhomogeneitiesinthewatervaporfieldandconvectiveinitiation.
July2011–August2011
HumidityExperiment2011(HUMEX)
Completed Thermodynamicparameters,includingwatervaporandtemperature,arehighlyvariableinspaceandtime.Therefore,itisimportanttoobservewatervaporandtemperatureprofileswithhighvertical,horizontal,andtemporalresolution.Remotesensinginstruments,includingmicrowaveradiometersandRamanlidars,canprovidewatervaporandtemperatureprofiles.Thisfieldexperimentmeasurestheseatmosphericparameterswithaverticalresolutionof50–100metersinthelowest3kilometersofthetropospherewithhightemporalresolution.
September2011–October2011
2011Full-ColumnGreenhouseGasSampling
InProgress TheSGPsitehasbecomeadefactofocalpointforevaluationofnewremotesensinginstrumentsthatdeterminegreenhousegas(GHG)mixingratiosfromtheground,airborne,andsatelliteplatforms.TheseactivitiesallrequirevalidationagainstinsitumeasurementsoftheverticalprofilesofGHGmixingratios.ThiscampaigndirectlysupportsbothcarboncyclesciencebeingconductedbythejointARM/LawrenceBerkleyNationalLaboratoryCarbonProjectandalargecomponentoftheothermajorGHGremotesensingmissionsconcernedwithaccurateassessmentoftheradiativeforcingderivedfromatmosphericGHGs.
On the inside covers: New and enhanced radars at SGP provide enhanced measurements of cloud properties and wind speed.
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ARM Climate Research Facility ANNUAL REPORT – 2011