Previous Seminars

Medium range predictability of summertime sea ice in the East Siberian Sea

Speaker: 
Takuya Nakanowatari
Affiliation: 
NIPR, Japan
Seminar Date: 
6. February 2017 - 13:00 - 13:30

A study of medium range predictability of summertime sea ice in the East Siberian Sea based on TOPAZ4 data assimilation system―Impact of initial conditions and atmospheric prediction skills.

An efficient training scheme that improves the forecast skill of a supermodel.

Speaker: 
Francine Schevenhoven
Affiliation: 
UiB
Seminar Date: 
2. February 2017 - 12:30 - 13:00

Weather and climate models have improved steadily over time as witnessed by objective skill scores, although significant model errors remain. Given these imperfect models, predictions might be improved by combining them dynamically into a so-called ``supermodel''. In this study a new training scheme to construct such a supermodel is explored using a technique called Cross Pollination in Time (CPT). In the CPT approach the models exchange states during the prediction.

Acoustic tomography in the Canary Basin (CAMBIOS 1997-8): Meddies and tides

Speaker: 
Brian Dushaw
Affiliation: 
NERSC
Seminar Date: 
26. January 2017 - 12:30 - 13:15

CAMBIOS was an acoustic tomography experiment deployed by IFREMER in the Canary Basin between Madeira and the Azores in 1997-8. The goal of CAMBIOS was to test whether the acoustical observations could quantify the flux of Mediterranean water into the western Atlantic. Such water often is carried as "Meddies" - self-contained, rotating eddies of 100 km horizontal extent and 500 m vertical extent. Meddies carry warm and salty water from the Mediterranean; they are density compensated, but not sound speed compensated. This talk revisits the CAMBIOS data.

Joint effect of sea level variations and wind waves on coastal flooding risks in the future climate – new insights

Speaker: 
Ulpu Leijala
Affiliation: 
Research Scientist at FMI Marine Research Unit and PhD student at University of Helsinki.
Seminar Date: 
19. January 2017 - 13:15 - 13:45

New methods to estimate the effects of extreme coastal sea level events in a more accurate and location-specific way are vital for secure planning and operation of densely populated coastal areas -areas that are strongly vulnerable to climate change consequences. In Finland, the global mean sea level rise predictions together with the past local short-term sea level variability have formed traditionally the basis of the sea level and flood probability projections for the future.

Courses in Geostatistics (3 days)

Speaker: 
Hans Wackernagel
Affiliation: 
Ecole des Mines de Paris, ParisTech
Seminar Date: 
9. January 2017 - 9:00 - 13. January 2017 - 15:00

Basics of Geostatistics from exploratory data analysis to kriging and conditional Monte Carlo simulations. It will take place on Monday 9th, Tuesday 10th and Friday 13th (brrr) January 2017.

Morning session 9-12: seminars
Afternoon session 13-16: Practical lab.

During the course we will use R together with the graphical interface RStudio and the geostatistics package RGeostats.
So, please bring your laptop with you and install before the course:

- the latest version of the software R: http://www.r-project.org/
- the graphical interface RStudio: http://www.rstudio.com

Scientific Platform as a Service - tools and solutions for efficient access to and analysis of oceanographic data at NERSC

Speaker: 
Morten W. Hansen
Affiliation: 
NERSC
Seminar Date: 
20. December 2016 - 12:30 - 13:00

The Effects of Model Error on the Ensemble Kalman Filter for the Linear Shallow Water Equations

Speaker: 
Colin Guider
Affiliation: 
PhD student at University of North Carolina
Seminar Date: 
16. November 2016 - 12:30 - 13:00

We consider the motion of a drifter in a flow field governed by the Linear Shallow Water Equations. The true trajectory of this drifter is affected by its mass. We introduce this an inertial parameter and study the resulting dynamical system. Further, assuming this drifter is a passive ocean instrument giving Lagrangian measurements, we give preliminary results on the efficacy of the Ensemble Kalman Filter (EnKF). We consider the case when the data assimilation algorithm assumes a massless drifter, and the case when the algorithm takes the inertia into account.

New developments in data assimilation in MIKE 21/3

Speaker: 
Jesper Mariegaard
Affiliation: 
DHI Group, Dk
Seminar Date: 
8. November 2016 - 11:15 - 11:45

DHIs marine 2d and 3d models MIKE 21/3 are capable of modelling flow and physical processes like sand transport, bacterial plumes, oil spill etc. A data assimilation module for MIKE 21/3 has been developed 10 years ago and developments have been sparse since then, but recently it has been given new life and a lot of attention in the FP7-LOTUS project and NordForsk EmblA Center of Excellence. The new developments include parallelization with MPI, assimilation of track data (e.g. satellite altimetry), Ensemble OI and localization in space and time.

Amplified Arctic Warming and Mid-latitude Weather : Emerging Connections

Speaker: 
Prof. Jennifer Francis
Affiliation: 
Institute of Marine and Coastal Sciences, Rutgers University, New Jersey, USA
Seminar Date: 
4. October 2016 - 11:15 - 12:00

In this presentation I will discuss recent research illuminating the various seasonal and regional mechanisms by which the rapid warming of high northern latitudes may be affecting weather patterns in mid-latitudes, including extreme events. While studies based on both observations and model simulations have made progress in identifying these linkages, questions remain as to the relative importance of amplified Arctic warming and other factors from lower latitudes, as well as the state dependence of these influences. New metrics are opening windows to understanding this complex topic.

Ocean Acoustic Tomography in Fram Strait: Past Paths and Future Directions

Speaker: 
Brian Dushaw
Affiliation: 
NERSC
Seminar Date: 
29. September 2016 - 12:30 - 13:15

This talk will provide a brief review of the four recent publications listed below, and then conclude with some comments and speculations on some possible future directions.

Brian D. Dushaw, Hanne Sagen and Agnieszka Beszczynska-Möller, Sound speed as a proxy variable to temperature in Fram Strait, J. Acoust. Soc. Am., 140, 622-630 (2016).
http://dx.doi.org/10.1121/1.4959000