Previous Seminars

Automated sea ice classification using Sentinel-1 imagery

Speaker: 
Jeong-Won Park (Ocean and Sea Ice Remote Sensing)
Seminar Date: 
26. March 2019 - 11:15 - 11:45

Sentinel-1A and 1B operate in Extra Wide swath dual-polarization mode over the Arctic Seas, and the two-satellite constellation provides the most frequent SAR observation of the Arctic sea ice ever. However, the use of Sentinel-1 for sea ice classification has not been popular because of relatively higher level of system noise and radiometric calibration issues. By taking advantage of my recent development on Sentinel-1 image noise correction, we suggest a fully automated SAR image-based sea ice classification scheme which can provide a potential near-real time service of sea ice charting.

Impact of sea ice sources on calibrating a wave-ice interaction model

Speaker: 
Sukun Cheng
Affiliation: 
NERSC
Seminar Date: 
22. March 2019 - 11:00 - 11:30

Because of the interaction between ocean wave and sea ice, reliable models for wave propagation in the ice-covered region is critical to sea ice morphology. We present calibration of a viscoelastic type wave-in-ice model with wave, wind, and ice data collected from the Beaufort and Chukchi seas in the autumn of 2015. The data were from multiple sources of in-situ and remote sensing measurements in the marginal ice zone during the ice advance season.

Using a regional ocean model to understand the structure and sampling variability of acoustic tomography arrivals in Fram Strait

Speaker: 
Florian Geyer (Polar Acoustics and Oceanography)
Seminar Date: 
5. March 2019 - 11:15 - 11:45

A regional ocean model for Fram Strait allows to understand the variability and structure of acoustic tomography arrivals. The eddy-permitting model (52 vertical layers and 4.5 km horizontal resolution) was evaluated using long-term moored hydrography data and time series of depth-range averaged temperature obtained from the inversion of acoustic tomography measurements. Geometric ray modelling on the ocean model fields reproduces the measured arrival structure of the acoustic tomography experiment.

Model Calibration Using Warping Metrics: With Application to Sea Ice Deformation in MPM-ice

Speaker: 
Christian Sampson
Affiliation: 
University of North Carolina in Chapel Hill
Seminar Date: 
25. February 2019 - 11:30 - 12:00

Sea Ice is a critical component of earth’s climate system and mediates a broad range of physical processes in the Arctic, such as ocean-atmosphere interaction. Increased warming in the Arctic has drastically changed sea ice dynamics in the region and the ice composition, thinner and more first year ice, and an increased marginal ice zone. Accurate representation of lead formation is now more important than ever for the calculation of important climatological variables, such as oceanic heat flux.

Combining Data Assimilation and Machine Learning to emulate a numerical model from noisy and sparse observations

Speaker: 
Julien Brajard (Data Assimilation)
Seminar Date: 
12. February 2019 - 11:15 - 11:45

Is it possible to emulate a numerical model from noisy and sparse observations? How realistic and skillful can it be?

Warmer urban climate in Arctic cities, By: Igor Esau, Victoria Miles and the HIARC project team

Speaker: 
Igor Esau (Climate Dynamics and Prediction)
Seminar Date: 
22. January 2019 - 11:15 - 11:45

The recent IPCC special report on 1.5C warming target has envisioned a number of detrimental effects and environmental challenges that will emerge with the global warming in excess of the target. Our study reveals that majority of the Arctic population is already leaving in the climate conditions significantly warmer than 1.5C and even 3.0C above the mean XXth century regional temperature. These urban temperature anomalies, known to as the urban heat islands (UHIs), may help us to study the effects of the warmer climate in the Arctic region.

Two-way nesting in coupled atmosphere-ocean modelling

Speaker: 
Prof. (emeritus) Dr. Lars Petter Røed
Seminar Date: 
17. January 2019 - 12:30 - 13:30

Nansen Lecture based on Røed's recently published book by Springer titled: “Atmosphere and Ocean on Computers”.

Applications of operational oceanography product to fisheries management and operation

Speaker: 
Dr. Hiromichi Igarashi
Affiliation: 
JAMSTEC, Yokohama, Japan
Seminar Date: 
3. December 2018 - 12:30 - 13:10

Operational oceanography products, reanalysis, NRT analysis and forecast ocean state, can provide us a variety of value-added information useful for fishery stock management, monitoring and efficient fishery operation. In this talk, applications of the operational products to the operational fisheries in the North Pacific conducted by JAMSTEC data synthesis research group will be presented.

A Nested-Grid Snow Modeling System

Speaker: 
Dr. Glen E. Liston
Affiliation: 
Colorado State University
Seminar Date: 
14. November 2018 - 11:00 - 12:45

Over the last 35 years, Dr. Liston has developed a snow-evolution modeling system (MicroMet, SnowModel, and SnowAssim) that can be used for a wide range of snow and other cold-season, cold-region applications. The model formulation is general enough to allow simulations over temporal domains spanning days to decades, and spatial domains spanning from local measurement sites to pan-Arctic regions at spatial resolutions ranging from 1-m to 10-km.

Dynamical downscaling of CMIP5 for future projection of the North Pacific Ocean state

Speaker: 
Tsuyoshi Wakamatsu (Ocean Modeling)
Seminar Date: 
6. November 2018 - 11:15 - 11:45

The North Pacific Ocean (NPO) state is about to experience significant transition by the end of this century under the current trend of the global climate change. NPO coastal communities are now facing a challenge to establish adaptation plans to mitigate impacts of the climate change to their socio-economical environment. The best resource to provide the future projection of an ocean state available today is CMIP5 data and they have been used substantially for evaluating future coastal marine environment.