Previous Seminars

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

Calibration and performance of the GlobCurrent combined current using triple collocation

Speaker: 
Rick Danielson
Seminar Date: 
15. June 2016 - 15:30 - 16:30

As compared to the analysis of many common geophysical variables, the ocean surface current is a relatively new and unfamiliar challenge. A number of initiatives seek to improve the exploitation of satellite observations and provide more accurate historical and near real time information. In parallel, a synopsis of the performance of retrievals and analyses, based on the method called triple collocation, is also available following Stoffelen (1998) and McColl et al. (2014).

Google Earth Engine: easy way to work with satellite data in the Google cloud

Speaker: 
Anton Korosov
Seminar Date: 
2. June 2016 - 13:00 - 13:45

Google Earth Engine: 'A planetary-scale platform for Earth science data & analysis'
Interactive presentation of simple access to visualization and effective processing of vast satellite data. Seminar is for researches from any field and IT personnel who want to analyse satellite data, but don't want to bother with data download, software installation and development. Based on experience from the course, Google gave at ESA Living Planet Symposium in Prague.

Lessons learned from the neXtSIM-F forecasting platform

Speaker: 
Philipp Griewank
Affiliation: 
NERSC
Seminar Date: 
31. May 2016 - 14:15 - 15:00

In this talk I'll give an overview over the strengths and weaknesses of the neXtSIM-F forecasting platform I set up during my 2-year postdoc at NERSC. The talk will begin with a description of the model setup and assimilation method used which evaluated through hind casts, and the presentation will finish with an evaluation of the forecasts performed from 2015-11 to 2016-04.

Global glacier mass change and its causes on the centennial time scale

Speaker: 
Ben Marzeion
Affiliation: 
Institut für Geographie, Universität Bremen, Germany
Seminar Date: 
13. May 2016 - 10:15 - 11:00

Melting glaciers were likely the dominant cause of sea-level rise during the 20th century. Currently, glaciers are contributing about as much to sea-level rise as the Greenland and Antarctic ice sheets combined, and also about as much as thermal expansion. During the 21st century, the relative contribution of glaciers is going to decrease, but they will remain an important part of the sea level budget also within the 22nd and 23rd centuries. I will discuss methods of reconstructing and projecting global glacier mass change, and present their results.

An Empirical Model for Mode-1 Internal Tides Derived from Satellite Altimetry: Computing Accurate Tidal Predictions at Arbitrary Points Over the World Oceans

Speaker: 
Brian Dushaw
Affiliation: 
NERSC and the Applied Physics Laboratory, University of Washington, Seattle
Seminar Date: 
31. March 2016 - 12:30 - 13:30

A global estimate for harmonic constants of mode-1 internal tides is described, enabling accurate predictions of internal tide amplitude and phase in most regions of the world's oceans. The estimates are derived from TOPEX/POSEIDON altimetry, building on a frequency-wavenumber tidal analysis technique described by Dushaw et al. (2011) [B. D. Dushaw, P. F. Worcester, and M. A. Dzieciuch, 2011. On the predictability of mode-1 internal tides, Deep-Sea Res. 58, 677-i698].

The Brazilian Oceanographic Modeling and Observation Network (REMO): Status and Plans

Speaker: 
Prof. Clemente A. S. Tanajura
Affiliation: 
Instituto de Física, Universidade Federal da Bahia (UFBA), Brasil
Seminar Date: 
30. March 2016 - 12:00 - 12:45

This talk will present a general view of the Brazillian REMO group in physical oceanography and operational oceangraphy in the South Atlantic. It will focus on the REMO ocean data assimilation system (RODAS) based on the Ensemble Optimal Interpolation method and the work by researchers from NERSC and the Institute of Atmospheric Physics (IAP/CAS). Some preliminary results will be also presented in an attempt to improve the current system.

The GAIA-CLIM project: Characterizing satellite measurements using in-situ, ground-based and sub-orbital capabilies

Speaker: 
Anna Christina Mikalsen
Seminar Date: 
30. March 2016 - 11:00 - 11:30

This presentation will provide an overview on the H2020 project "Gap Analysis for Integrated Atmospheric ECV CLimate Monitoring (GAIA-CLIM)".

The GAIA-CLIM project aims to improve our ability to use (ground-based and sub-orbital) non-satellite observations to characterise satellite observations for a number of atmospheric Essential Climate Variables (ECVs). The key outcomes will be a “Virtual Observatory” facility of co-locations and their uncertainties and a report on gaps in capabilities or understanding, which shall be used to inform subsequent Horizon 2020 activities.

The Wind-Driven Ocean Circulation: Bifurcations, Simulations and Observations

Speaker: 
Michael Ghil
Affiliation: 
Ecole Normale Supérieure, Paris, and University of California, Los Angeles
Seminar Date: 
18. March 2016 - 14:00 - 15:00

The large-scale, near-surface flow of the mid-latitude oceans is dominated by the presence of a larger, anticyclonic and a smaller, cyclonic gyre. The two gyres share the eastward extension of western boundary currents, such as the Gulf Stream or Kuroshio, and are induced by the shear in the winds that cross the respective ocean basins. The boundary currents and eastward jets carry substantial amounts of heat and momentum; the jets also contribute to mixing in the oceans by their "whiplashing" oscillations and the detachment of eddies from them.