unusual ice conditions in iceland during the winter of 2007 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Unusual ice conditions in Iceland during the Winter of 2007 PowerPoint Presentation
Download Presentation
Unusual ice conditions in Iceland during the Winter of 2007

Unusual ice conditions in Iceland during the Winter of 2007

303 Vues Download Presentation
Télécharger la présentation

Unusual ice conditions in Iceland during the Winter of 2007

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Unusual ice conditions in Iceland during the Winter of 2007 Unusual ice conditions in Iceland during the Winter of 2007 Ingibjörg Jónsdóttir Institute of Earth Sciences - University of Iceland VIII Meeting of the International Ice Charting Working Group Science Workshop ESA ESRIN, Frascati Italy 22.-26.10. 2007

  2. Why the Institute of Earth Sciences? • Interest in remote sensing (teaching and research) • The sea ice is one of the most interesting and yet challenging phenomena to study with remote sensing: All sensors are used, the ice is a highly variable feature and changes fast, the environment is fairly difficult (dark, cold, usually not much ground truth data), information needs to get quickly to users - and in as few kb as possible... • Increased traffic north of Iceland causes concern, there is pressure to decrease oil usage by the fishing fleet and recently (with 1/3 cut of the fishing quota last year) there is more interest in fish farming. • The captains want to avoid all ice, so ice extent charts are of prime interest. • Interest in ice monitoring and information needs • How to get what kind of information to the users? • Development of new products with the users. • Privilege of participating in ice reconnaissance flight when needed and having good connection with the data users. • Ground truth data reasonably easy to get. • Sea-ice climatology • Sea ice can greatly affect the climate in Iceland, and caused famine in the past. Even if this is not likely to happen in the next few years or decades, it is of historical interest to study the ice. This is the justification for me working on this and the work has been carried out for a few years. This year however, the service became almost operational since ice was causing trouble and the information was not available elsewhere. So basically, a small sea-ice centre evolved at the IES. It will continue as long as I can justify to myself spending so much time on it...

  3. So here is the result, a rather badly designed web page, frequently updated • with new sea-ice and other information (especially when the ice is within Icelandic waters). • All possible sources are used, but by far the most important source is the one • provided by Leif Toudal and colleagues at the Danish National Space Center.

  4. Warning! Before we look at any of the charts... • I have not adopted the IICWG "look" yet and ask you not to use it against me. • classify according to sources and days • The products are developed in close co-operation with the users, and are still changing since we are trying to combine the ice data with other information. • We will get there though.

  5. Ice conditions in early 2007 • Blocking high pressure system south of Iceland caused SW winds in the Denmark Strait for weeks, pushing the ice towards the NW peninsula of Iceland. • Various types of images were used to monitor the situation, most important were ENVISAT (300m) from, the Danish National Space Center.

  6. The atmospheric pressure in Tasiilaq, East Greenland, is normally higher than in Bolungarvík NW Iceland. When the pressure difference is little or negative (T higher than B) then ice is pushed quite rapidly towards Iceland

  7. Once at the coast... • The big ice band packed into one fjord, but much less got into other fjords. • When flying over it the next day ice was forming in that fjord but had melted in the others. • It is extremely unusual to have ice that far south at the NW peninsula, and did not happen in the "ice years" after 1965 • It is the second time in three years that unusual pressure patterns have brought ice towards Iceland. The ice did also reach the coasts in 2005.

  8. Briefly on the Icelandic ice indices... ... since the cold period, or the "sea-ice years" which started in 1965 began with relatively little amount of ice in the Denmark Strait but unusual pressure patterns. Data resolution: seasonal 1600-1850 monthly 1850 onwards purple bars - five year accumulative indices blue bars - annual data Astrid E.J. Ogilvie 1600-1850 Ingibjörg Jónsdóttir 1850-2006

  9. So what is happening? • I am not forecasting another period of ice years in Iceland like in 1965 as the overall amount of ice is less now. • It is worrying to see that amount of multi year ice flowing out of the Arctic. • The ice conditions are looking "promising" this year, as the ice is forming fast in the East Greenland Current and flowing rapidly south.

  10. Lot of opportunity to compare different data sources.

  11. An example of data provided to the fishing fleet.

  12. Discussion • Extremely worrying situation in the Arctic • Strange situation in Iceland - discussion of disappearing ice going on at the same time as ice information is needed badly. • The IES will continue this work, though creating a more stable look to prevent people getting too confused. • Increased focus on icebergs and fjord ice, along with further experiments with sea-ice forecast.

  13. Thank you for your attention! And specially: • Leif Toudal and co • KSAT • Dundee Satellite Receiving Station • DMI