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Lars H. Smedsrud

Professor,  Geophysical Institute,
University of Bergen


part of the Bjerknes Centre for Climate Research




Lars H. Smedsrud has a wide experience in polar oceanography. He is now a professor II at the University Centre in Svalbard (UNIS),
and help coordinating the research group on atmosphere, cryosphere, ocean processes at the Bjerknes Centre.


In March 2000 Smedsrud accomplised his PhD on frazil ice formation and sediment entrainment in polar waters, and has worked with projects related to sea ice formation in the Arctic and melting of ice-shelves in Antarctica since then. Smedsrud has extensive field experience, has been cruise leader during the International Polar Year, participated in several international laboratory experiments, and worked with a number of numerical models. Modelling activity includes vertical column modelling of the Arctic Ocean and sea ice cover, sub ice shelf circulation under the Fimbul Ice Shelf in Antarctica, polynya dynamics on Svalbard, and melting and export of sea ice in Global Earth System Models.


Research areas:


Melting of the Antarctic ice sheet;
The Fimbul Ice Shelf - Top to Bottom - has over the last years tried to estimate the overall mass balance of the largest ice shelf along Queen Maud Land in Antarctica. This floating part of the Antarctic ice sheat is special because it is overhanging the continental slope. Outside the Fimbul ice shelf relatively warm water resides, and the water warmed significantly from the 1970's to 2001 as described in a paper in Deep Sea Research. The warm water enters into the cavity, governing the melting of the ice shelf. A numerical study showing temperature fields and currents is published in Journal of Geophysical Reserach, but new data now suggest that the model needs modifications. At the surface new sea ice formation takes place, and this leads to salt rejection which makes the water dense enough to sink down along the slope, and renew the bottom water of the world oceans. A study of the downflow of this dense water on the Weddell continental shelf is published in Tellus.

Modeling the Arctic Ice Cover; A coupled air-ice-ocean culumn model has been very useful in a number of studies. The important processes are included, and results indicate that the sea ice export is a stronger driver of thinning for the ice than the estimated increased oceanic heat transport. Heat transport in the atmosphere have remained on the same level as around 1990 and cannot explain the recent ice loss. Satellitte images show that the ice export has increased steadily since 2004, and a paper in The Cryosphere has all the details. If the ice export remains as high as presently  the Arctic ice-cover will remain close to the present level. But, if the export decrease to the previous lower level, the Arctic ice-cover could recover significantly. On longer timescales increase in radiation due to increased green house gases leads to a 95 % open water situation during summer 2050 (a 2*CO2 scenario). First results were descibed in a Geophysical Research Letter and these were sort of confirmed in a new study in Ocean Modelling.

Sea ice formation in open water; I study how the first ice formation depend on the surrounding forcing, mostly the wind speed creating turbulence in the ocean, snow drift and high heatfluxes to the cold air above. If the first ice cover becomes a thin layer of solid ice rather than a layer of slush, heat fluxes will be an order of magnitude lower, and less salt will be released to the ocean below. The first field work in Polar Ocean Climate Processes took place in March 2003 in Svea. The next three field seasons were spent at a cabin on Edge Øya in Storfjorden. If you have a good internet connection (> 1 Mbit/s) and Windows Media Player, you may watch a film from the fieldwork: "When the ice comes". Scientific results may be found in a Cold Regions Science and Technology article. When sea water freezes and the water is sufficiently turbulent from wind or tides, frazil ice formation will be the result. These crystals look much like snow flakes, and are diffused down into the water. They contribute to a more efficient ice formation and thereby also a higher salt flux then during normal congelation ice growth. Frazil ice forms in rivers, in leads or polynyas, and below Antarctic ice shelves. Image of congealed frazil ice.



Publications  (abstracts & full text PDF's)   
Curriculum Vitae (CV)
Talks & Posters
Media & popular science

Active projects
Dynawarm (Dynamics of past warm climates)
N-ICE 2015 (Norwegian young sea ICE cruise 2015)
ice2ice (Arctic Sea Ice and Greenland Ice Sheet Sensitivity)
BASIC (Boundary layers in the Arctic atmosphere, Seas and Ice dynamics)

Supervsion and teaching

Supervsion of PhD students: Marius Årthun (22.09.2011), Sara de la Rosa (30.09.2011), Marta Zygmuntowska (11.06.2014), Aleksi Nummelin, Ingrid Onarheim, 
Supervisioin of Master and Bachelor students: Ingrid Onarheim (12.06.2013),
Océane Richet (20.08.2013), Natasha Ridenour (12.06:2014),
Mari Halvorsen (18.06.2014),
Martin Arntsen (Juni 2015), Morven Muilwijk (Juni 2016).
Teaching:
Data analysis in Oceanography og Meteorology (GEOF210, autumn 2007 and 2013),
Polar Oceanography (GEOF335, spring 2013, GEOF338 spring 2014), Physics of the Atmosphere and Ocean (GEOF105, autumn 2014)

Activity

Bergen Ice Group and related fieldwork
Atmosphere, cryosphere and ocean processes (RG5@BCCR) official web page
webblogg for RG5@BCCR


Previous projects
Fimbul Ice Shelf - Top to Bottom
Bipolar Atlantic Thermohaline Circulation (BIAC)
NorClim
Polar Climate and Heat Transport (Pocahontas)
REduced ice Cover in the ARctic Ocean (RECARO)
Polar Ocean Climate Processes (ProClim)
Transport Programme

Previous administrative duties;
Forum for Research into Ice Shelf Processes (FRISP)    www pages and editor of reports 2002-2007
Norwegian Ocean and Climate Project, NOClim  and  Polar Ocean Climate Processes, ProClim   www pages, and outreach


Photoalbum


Adress

Lars Henrik Smedsrud
Geophysical Institute 
Allégaten 70, 5007 Bergen, Norway 

Office: 135 (Central building, first floor) 

Phone: +47 55 58 26 38 
Fax:     +47 55 58 98 83 
Email: larsh@gfi.uib.no
Web: www.uib.no/People/ngfls