NERSC News Archive

Ensemble Optimal Interpolation: multivariate properties in the Gulf of Mexico

In a paper published in Tellus A Drs. Francois Counillon and Laurent Bertino present an ocean model system for the Gulf of Mexico and the ensemble optimal interpolation (EnOI) methods developed under Counillon Ph.D. studies at the Nansen Center.

The EnOI extracts its covariance matrix from a historical ensemble and allows for a multivariate update at a small computational cost. The Sea Level Anomaly (SLA) is used for assimilation, as it provides an integral representation of the circulation in the area.

High resolution ensemble forecasting for the Gulf of Mexico eddies and fronts

Stochastic forecasting is widely used in meteorology, in order to provide confidence indices of the prediction (Molteni et al., 1996). Stochastic forecasting is introduced by Yin and Oey (2007) for application to the GOM.

In a paper published in Ocean Dynamics Drs. Francois Counillon and Laurent Bertino present a sensitivity study to different perturbation systems is carried out by perturbing the initial state, lateral forcing, and atmospheric forcing.

Ola M. knighted : Portrait on national TV2

See TV portrait: Windows media Mac media

His Majesty the King of Norway has appointed Professor Ola Mathias Johannessen to Officer of The Royal Norwegian Order of St. Olav for his efforts in climate and polar research. On behalf of the King the assistant County Governor of Hordaland, Rune Fjeld delivered the decoration of the Order to Ola M.

GRL cover publication: Improving ocean surface velocity measurements from space

The Nansen Centers in Bergen and St. Petersburg in cooperation with IFREMER and BOOST Technologies in France obtained the cover publication in Geophysical Research Letter.

Advanced synthetic aperture radar (ASAR) signals collected by ESA´s Envisat help scientists map surface currents in the world oceans. As demonstrated, ASAR is a valuable source of high-resolution information on the line-of-sight roughness and velocity of the moving ocean surface.

Season Greetings from the Nansen Center

We thanks all our partners for the cooperation in 2008 and wish you a Merry Christmas and all the best for 2009.

Book contribution: High North - high stakes

The Arctic, once politically and literally frozen, is melting at a pace unforeseen even a few years ago. Arctic petroleum resources are of great interest in an ever-tightening global energy market, and there is a considerable potential for increased shipping in and through the region.

Meeting 9. December: "Our Northern Region - Status and Challenges"

The Norwegian Academy of Science and Letters (DNVA), The Norwegian Scientific Academy for Polar Research (NVP) and The Norwegian Academy of Technological Science (NTVA) invites to a public seminar in Bergen

Tuesday 9 December 2008 at 19:00
Nansensenteret at Marineholmen, Thormøhlensgate 47

Our Northern Region – Status and Challenges

Lectures by:
Elisabeth Walaas, State Secretary, Ministry of Foreign Affairs
Prof. Yngve Kristoffersen, University of Bergen
Prof. Ola. M. Johannessen, Nansen Center, Bergen

Ola M. appointed the Royal Norwegian Order of St. Olav

His Majesty the King of Norway has appointed Professor Ola Mathias Johannessen, founding director ot he Nansen Center, to Officer of The Royal Norwegian Order of St. Olav for his efforts in climate and polar research.

The Council of the Order has in its evaluation considerably emphasized his efforts in the research of polar oceans.

Doktor disputas: Hva kontrollerer blomstringen av planteplankton i Norskehavet?

Blomstring av planteplankton kontrolleres av tilgang på næringsstoffer og lys, i likhet med andre planter. Det er antatt at variasjoner i dyreplankton bestander kan relateres til endringer i planteplankton. Siden mange fiskearter er avhengige av dyreplankton for å vokse og overleve, er det viktig å forstå variasjoner i planteplankton og om dette kan varsles.
Det er dyrt og tidkrevende å hente inn observasjoner av planteplankton, næringsstoffer, salt og temperatur på havet. I tillegg kan man ikke dekke både tid og rom, derfor benytter vi oss av havmodeller.

The Nansen-Zhu Centre 5 years

The five years anniversary of the Nansen-Zhu International Research Centre (NZC) was celebrated with a scientific colloquium in Beijing on November 3rd and 4th. The Norwegian Minister of Research and Higher Education Tora Aasland and the Vice-president of the Chinese Academy of Sciences (CAS) Prof. Zhongli Ding visited the Nansen-Zhu Centre during the anniversary. NZC is located at the Institute of Atmospheric Physics (IAP) of CAS and named in the honour and spirit of the Norwegian scientist, humanist and diplomat Dr.

The Third Nansen–Zhu Ph.D. summer school in Beijing

The Nansen–Zhu International Summer School focus this year on “Climate Teleconnections between Low and High Latitudes” has to day opened at the Nansen-Zhu International Research Centre in Beijing. More than 100 participants including lecturers and Ph.D. students from the several Universities in China, Norway and Russia as well as the Nansen Centers in Bergen, St. Petersburg, Cochin and Beijing will during the next five days give lectures and have discussion on the state of the art in research on teleconnections in the climate system.

EUs havovervåkningssamarbeide med Kina koordineres fra Bergen

Denne uken samles mer enn 20 forskere fra åtte kinesiske og fem europeiske institusjoner for å diskutere harmonisering av de operative system for havovervåkning og varsling for de to kontinent.

Nansen senter for miljø og fjernmåling (NERSC) i Bergen er vertskap for møtet og Forskningsdirektør Johnny A. Johannessen er koordinator for dette EU finansierte prosjektet ”DRAGONESS – DRAGON in support of harmonizing European and Chinese marine monitoring for Environment and Security System”.

GRL publication in press: Recent and future changes of the Arctic Sea Ice Cover

The interest in the Arctic Sea Ice seems inversely proportional to the area covered, and has exploded after the record minimum in September 2007, which were not beaten this year (see below articles). The Arctic ice has in many ways become the “canary in the coal mine” of global warming, but at the same time global models show a large spread in future predictions of the Arctic energy budget.

The publication “Recent and future changes of the Arctic Sea Ice Cover” by Lars H.

No new ice minimum in the Arctic in 2008

The drifting sea ice in the Arctic is an indicator of climate variability, which is caused both by natural and increased greenhouse gasses by human activities.

Last years record minimum ice area of less than 4 mill km2 compared to the average value of 6 mill. km2 over the 1979-2007 period, lead to speculation by many research groups that the ice cover in the Arctic had reached a tipping point and that it would disappear during the summer at a much earlier time than projected by the Intergovernmental Panel on Climate Change (IPCC) of the United Nations.

Arctic ice area for 2008 getting close to the extreme minimum of 2007

The ice area minimum in the Arctic happens every year in mid to late September, when the melting season in the Arctic is over. Even though the ice area today is about 100.000 km2 above last year’s minimum, both the Northeast- and Northwest passages are ice free, something that has probably not happened since before the last Ice Age, 100.000 – 125.000 years ago.

The Nansen Environmental and Remote Sensing Centre in Bergen, Norway continuously monitor the ice conditions in the Arctic using satellite observations. The Centre receives new satellite observations on a daily basis.

Ocean modeling of the Gulf of Mexico

François Counillon will defend his Doctoral thesis "Ensemble-based data assimilation and forecasting with an eddy-resolving model of the Gulf of Mexico" on Friday the 12th September at 13:15, at the Nansen Center/Geophysical Institute, University of Bergen.

The main objective of the thesis is to develop and validate a state of the art operational ocean forecasting system for the Gulf of Mexico region.

The thesis contains three referee publications on:

• Implementing a state of the art eddy resolving model for the Gulf of Mexico and analyzing the capability and limitations of the EnOI

Acoustic Monitoring of the Fram Strait

The Nansen Center and collaborating partners have this week launched an acoustic tomography experiment in the Fram Strait as part of the DAMOCLES EU project. The first acoustic source and receivers were successfully deployed on 15th and 16th August from RV Håkon Mosby with Dr. Hanne Sagen as cruise leader.

The tomography system will measure travel time of sound signals in different depths of the water column. The data from the array will be recovered during summer 2009 and be converted to a year-long record of temperature measurements across the West Spitzbergen Current.

Arctic Security - our Annual Report for 2007 available

Global warming is enhancing in the Arctic regions. The air temperature has increased to double that of the global average over the last 100 years, the ice cover is decreasing at a rate of 3 – 5% per decade while the thicker multi-year ice is decreasing at a rate of 7 – 10% per decade, the river discharge from Russia is increasing, the tundra-permafrost is thawing and the snow cover on land is decreasing. Furthermore, in the past few years the Greenland ice sheet has lost mass along its edges – more than the accumulation increase in the interior.

Favorable book reviews in EOS and Polarforschung

The joint Norwegian Russian book "Remote Sensing of Sea Ice in the Northern Sea Route – Studies and Applications" by O. M. Johannessen, V. Yu. Alexandrov, I. Ye. Frolov, S. Sandven, L. H. Pettersson, L. P. Bobylev, K. Kloster, V. G. Smirnov, Ye. U. Mironov and N. G. Babich , was published by Springer-Praxis in 2007 and in Russian language by Nauka in 2008.

Two Nansen Fellowship Ph.D. dissertations in Saint Petersburg

Dr. Natalia Ivanova has successfully defended her Ph.D. dissertation “Radar sounding of sea water pollution: theoretical modeling and practical applications”. The dissertation took place at the RosHydrometeorological University in Saint Petersburg on July 19. All the 26 members of the scientific evaluation committee unanimously approved her high quality research work that has been performed at the Nansen International Environmental and Remote Sensing Centre (NIERSC).

Syndicate content