Global and direct UV irradiance variation in the Nahuel Huapi National Park (Patagonia, Argentina) after the eruption of Puyehue-Cordon Caulle (Chile).

S.B. DIAZ, ; A.A.PALADINI, ; H.G.BRAILE, ; M.C.DIEGUEZ, ; G.A.DEFERRARI, ; M. VERNET, .; VRSALOVIC J

JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2014 vol. 112 p. 47 - 56

1364-6826

On June4th,2011,thePuyehue-CordonCaullevolcaniccomplex(40135025??S 72107002??W,Chile)started eruption, sendingash45,000feetintotheatmosphere.Aftertheinitialperiod,theeruptioncontinued for severalmonths,withlessintensity.ChangesinglobalirradianceintheUV-BandUV-A,anddirect irradiance andAODintheUV-A,asconsequenceoftheeruption,werestudied.Globalirradiancehas been permanentlymeasuredattheLaboratoryofPhotobiology(LPh)(41.13S,71.42W,804msl)since 1998.Inaddition,intheframeofaprojecttostudyaltitudeeffectondirectandglobalirradiance, field campaigns wereperformedduringSeptember17thto23rd,2010andSeptember14thto18th,2011,in the regionoftheNahuelHuapiNationalPark,near100kmfromtheeruption.Inthoseperiods, simultaneous measurementsofdirectandglobalirradianceandaerosolopticaldepth(AOD)were carried outatthreesites:LaboratoryofPhotobiology(LPh),MtOtto(41.15S,71.38W,1386msl)and Mt Catedral(41.17S,71.48W,1930msl).Theanalysisofaerosolsin2011,threetofourmonthafterthe eruption started,showedthepresenceoflargerparticlesandmorevariabilitythanin2010,atallsites. Global irradiance,atLPh,alsoexhibitedlargervariability,comparedto1999,whennoeruptionorany other eventthatcouldhaveproducedmajorchangesinaerosolsoccurred.Themeandecrease,as consequenceofthevolcanoactivity,atLPh,wasaround20%,at305nmandclosedto10%,at320nm. At 380nm,thedecreasewasverysmallandnotstatisticallysignificant, althoughinparticulardays,with large aerosolload,asignificant decreasewasobserved.Directirradiance,intheUV-A,showedlarger decrease thanglobalirradiance.Theeffectoftheeruptionwasmorepronouncedatthelowaltitudesite. 135025??S 72107002??W,Chile)started eruption, sendingash45,000feetintotheatmosphere.Aftertheinitialperiod,theeruptioncontinued for severalmonths,withlessintensity.ChangesinglobalirradianceintheUV-BandUV-A,anddirect irradiance andAODintheUV-A,asconsequenceoftheeruption,werestudied.Globalirradiancehas been permanentlymeasuredattheLaboratoryofPhotobiology(LPh)(41.13S,71.42W,804msl)since 1998.Inaddition,intheframeofaprojecttostudyaltitudeeffectondirectandglobalirradiance, field campaigns wereperformedduringSeptember17thto23rd,2010andSeptember14thto18th,2011,in the regionoftheNahuelHuapiNationalPark,near100kmfromtheeruption.Inthoseperiods, simultaneous measurementsofdirectandglobalirradianceandaerosolopticaldepth(AOD)were carried outatthreesites:LaboratoryofPhotobiology(LPh),MtOtto(41.15S,71.38W,1386msl)and Mt Catedral(41.17S,71.48W,1930msl).Theanalysisofaerosolsin2011,threetofourmonthafterthe eruption started,showedthepresenceoflargerparticlesandmorevariabilitythanin2010,atallsites. Global irradiance,atLPh,alsoexhibitedlargervariability,comparedto1999,whennoeruptionorany other eventthatcouldhaveproducedmajorchangesinaerosolsoccurred.Themeandecrease,as consequenceofthevolcanoactivity,atLPh,wasaround20%,at305nmandclosedto10%,at320nm. At 380nm,thedecreasewasverysmallandnotstatisticallysignificant, althoughinparticulardays,with large aerosolload,asignificant decreasewasobserved.Directirradiance,intheUV-A,showedlarger decrease thanglobalirradiance.Theeffectoftheeruptionwasmorepronouncedatthelowaltitudesite.