{"id":6126,"date":"2026-10-19T09:48:30","date_gmt":"2026-10-19T09:48:30","guid":{"rendered":"https:\/\/phd.hi.is\/doktorsvorn\/doktorsvorn-i-jardvisindum-monika-wittmann\/"},"modified":"2026-10-19T09:48:30","modified_gmt":"2026-10-19T09:48:30","slug":"doktorsvorn-i-jardvisindum-monika-wittmann","status":"publish","type":"phd_defence","link":"https:\/\/phd.hi.is\/en\/doktorsvorn\/doktorsvorn-i-jardvisindum-monika-wittmann\/","title":{"rendered":"Doktorsv\u00f6rn \u00ed jar\u00f0v\u00edsindum- Monika Wittmann"},"content":{"rendered":"<div class=\"field-items\">\n<div class=\"field-item even\" property=\"content:encoded\">\n<p>\u00deri\u00f0judaginn 31. jan\u00faar ver Monika Wittmann doktorsritger\u00f0 s\u00edna vi\u00f0 Jar\u00f0v\u00edsindadeild H\u00e1sk\u00f3la \u00cdslands. Ritger\u00f0in ber heiti\u00f0: \u00c1hrif sandfoks og eldfjalla\u00f6sku \u00e1 snj\u00f3 og \u00eds (Impact of Icelandic dust and volcanic ash on snow and ice).<\/p>\n<p>Andm\u00e6lendur eru dr. \u00deorsteinn \u00deorsteinsson, s\u00e9rfr\u00e6\u00f0ingur hj\u00e1 Ve\u00f0urstofu \u00cdslands, og dr. Andreas Massling, v\u00edsindama\u00f0ur hj\u00e1 Arctic Research Centre, Faculty of Science and Technology, H\u00e1sk\u00f3lanum \u00ed \u00c1r\u00f3sum, Danm\u00f6rku.<\/p>\n<p>Lei\u00f0beinandi er dr. \u00der\u00f6stur \u00deorsteinsson, pr\u00f3fessor \u00ed Umhverfis-og au\u00f0lindafr\u00e6\u00f0i og Jar\u00f0v\u00edsindastofnun H\u00e1sk\u00f3lans.<\/p>\n<p>Einnig sitja \u00ed doktorsnefnd dr. Gerrit de Leeuw, pr\u00f3fessor vi\u00f0 Finnish Meteorological Institute og University of Helsinki, Finnlandi, dr. Outi Meinander, s\u00e9rfr\u00e6\u00f0ingur vi\u00f0 Finnish Meteorological Institute \u00ed Helsinki, Finnlandi, dr. Andreas Stohl, v\u00edsindama\u00f0ur vi\u00f0 Norwegian Institute for Air research \u00ed Kjeller, Noregi, og og Finnur P\u00e1lsson, verkefnastj\u00f3ri \u00ed j\u00f6klaranns\u00f3knum vi\u00f0 Jar\u00f0v\u00edsindastofnun H\u00e1sk\u00f3lans.<\/p>\n<p>Magn\u00fas Tumi Gu\u00f0mundsson, pr\u00f3fessor og deildarforseti Jar\u00f0v\u00edsindadeildar, stj\u00f3rnar ath\u00f6fninni.<\/p>\n<p>\u00c1grip af ranns\u00f3kn<\/p>\n<p>\u00c1 \u00cdslandi er a\u00f0 finna st\u00e6rstu sanda heims \u00far bas\u00edsku gj\u00f3skugleri. \u00deeir hafa myndast \u00far eldfjalla\u00f6sku fr\u00e1 fj\u00f6lda eldgosa og vi\u00f0 j\u00f6kul- og vatnsve\u00f0run gosbergs. Mj\u00f6g vindasamt er \u00e1 \u00cdslandi vegna legu landsins \u00ed brautum l\u00e6g\u00f0a eftir Nor\u00f0ur-Atlantshafi. Gn\u00e6g\u00f0 lausra efna (svifryks) \u00ed s\u00f6ndum landsins og vindas\u00f6m ve\u00f0r\u00e1tta gerir j\u00f6kla \u00e1 landsins \u00fatsetta fyrir sand- og \u00f6skufoki. Efni\u00f0 sem sest \u00e1 j\u00f6klana hefur \u00e1hrif \u00e1 endurkast s\u00f3larlj\u00f3ss fr\u00e1 yfirbor\u00f0inu. Yfirbor\u00f0i\u00f0 ver\u00f0ur dekkra og tekur upp meira af orku fr\u00e1 s\u00f3lgeislun, en \u00fea\u00f0 hefur \u00e1hrif \u00e1 orkub\u00faskap vi\u00f0 j\u00f6kulyfirbor\u00f0, leysingu og \u00feannig afkomu j\u00f6klanna.\u00a0<\/p>\n<p>\u00c1hrif eldfjalla\u00f6sku sem sest \u00e1 snj\u00f3 og \u00eds voru ranns\u00f6ku\u00f0 me\u00f0 tilraunum, b\u00e6\u00f0i \u00e1 tilraunastofu og \u00ed n\u00e1tt\u00farunni. Fundin voru m\u00f6rkin \u00fear sem \u00f6sku\u00feykkt er svo mikil a\u00f0 h\u00fan einangrar alveg og hindrar br\u00e1\u00f0nun \u00edss og reyndust \u00feau vera 9-15 mm. H\u00e1marksaukning br\u00e1\u00f0nunar var\u00f0 hins vegar \u00feegar \u00f6skulagi\u00f0 er um \u22641-2 mm \u00feykkt.<\/p>\n<p>Reiknil\u00edkani\u00f0 FLEXDUST, sem reiknar dreifingu loftborinna efna, var nota\u00f0 til a\u00f0 herma sandfok \u00e1 Br\u00faarj\u00f6kul \u00ed nor\u00f0ur Vatnaj\u00f6kli \u00e1ri\u00f0 2012. Vi\u00f0 \u00f6ll tilvik sandfoks sem komu fram \u00ed l\u00edkanreikningum m\u00e6ldist samsvarandi l\u00e6gra hlutfall endurkasta\u00f0s s\u00f3larlj\u00f3ss fr\u00e1 yfirbor\u00f0i vi\u00f0 sj\u00e1lfvirkar ve\u00f0urst\u00f6\u00f0var \u00e1 j\u00f6klinum. Vi\u00f0 ve\u00f0urst\u00f6\u00f0 n\u00e6rri jafnv\u00e6gisl\u00ednu Br\u00faarj\u00f6kuls, voru 10 tilvik verulegs sandfoks og uppsafna\u00f0 magn efnis var 20,5 g\/m2 samkv\u00e6mt l\u00edkanreikningunum.<\/p>\n<p>Kort af dreifingu ryks \u00e1 yfirbor\u00f0i Vatnaj\u00f6kuls voru ger\u00f0 eftir m\u00e6lingum \u00e1 rykmagni \u00ed snj\u00f3s\u00fdnum sem safna\u00f0 var af yfirbor\u00f0i (vi\u00f0 hausthv\u00f6rf) Vatnaj\u00f6kuls haustin 2013 og 2015. Einnig var bora\u00f0 eftir tveimur 4,5 m l\u00f6ngum kj\u00f6rnum \u00far efsta hluta hjarns \u00e1 safnsv\u00e6\u00f0i Br\u00faarj\u00f6kuls \u00e1ri\u00f0 2015. Kjarnarnir n\u00e1\u00f0u aftur til \u00e1rsins 2006 og greinileg rykl\u00f6g \u00ed \u00feeim rakin til hausthvarfa \u00e1ranna 2014, 2012, 2011 og 2008, en a\u00f0eins fannst mj\u00f6g l\u00edti\u00f0 ryk \u00e1rin 2007 og 2013.<\/p>\n<p>Um doktorsefni\u00f0<\/p>\n<p>Monika Wittmann er fr\u00e1 Austurr\u00edki, f\u00e6dd 1988. H\u00fan lauk meistaragr\u00e1\u00f0u \u00ed Mountain and Climatic Geography fr\u00e1 University of Graz \u00ed Austurr\u00edki \u00e1ri\u00f0 2013. Monika hefur teki\u00f0 n\u00e1mskei\u00f0 \u00ed j\u00f6klafr\u00e6\u00f0i vi\u00f0 H\u00e1sk\u00f3lann \u00e1 Svalbar\u00f0a, H\u00e1sk\u00f3la \u00cdslands og H\u00e1sk\u00f3lann \u00ed Z\u00fcrich.<\/p>\n<\/div><\/div>","protected":false},"featured_media":1966,"template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_phd_date_start":"","_phd_date_end":"","_phd_location":"A\u00f0albygging","_phd_admission":"A\u00f0gangur \u00f3keypis","_phd_thesis_title":"\u00c1hrif sandfoks og eldfjalla\u00f6sku \u00e1 snj\u00f3 og \u00eds (Impact of Icelandic dust and volcanic ash on snow and ice)","_phd_source_url":"https:\/\/gamli.hi.is\/vidburdir\/doktorsvorn_i_jardvisindum_monika_wittmann","_phd_source_node_id":"308926","_phd_source_type":"vidburdir","_phd_member_id":563,"footnotes":""},"phd_school":[113,93],"phd_discipline":[116],"class_list":["post-6126","phd_defence","type-phd_defence","status-publish","has-post-thumbnail","hentry","phd_school-jardvisindadeild","phd_school-verkfraedi-og-natturuvisindasvid","phd_discipline-phd-i-jardvisindum"],"_links":{"self":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6126","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence"}],"about":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/types\/phd_defence"}],"version-history":[{"count":0,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6126\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media\/1966"}],"wp:attachment":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media?parent=6126"}],"wp:term":[{"taxonomy":"phd_school","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_school?post=6126"},{"taxonomy":"phd_discipline","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_discipline?post=6126"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}