InTheLoop | 03.03.2014
Simulations Find Melting Antarctic Glacier Past the Point of No Return
The rapid retreat of Antarctica’s Pine Island Glacier (PIG)—the single largest contributor to sea level rise in Antarctica—has perhaps reached a point of no return. Unless the region experiences much colder conditions the retreat will continue, say three international modeling teams writing in Nature Climate Change. They came to this conclusion after running a number of simulations to model the glacier’s behavior. Today, the glacier accounts for 20 percent of the total ice discharge from West Antarctica, contributing 0.33 millimeters per year to global sea level rise. »Read more
ESnet's Inder Monga, Chris Tracy to Make Four Presentations at Global Optical Networking Conference
Between March 9-13, 12,000 attendees from more than 65 countries are expected to convene at San Francisco’s Moscone Center for OFC 2014, the Optical Fiber Communication Conference and Exposition. Among the speakers are ESnet Chief Technologist Inder Monga and ESnet Network Engineer Chris Tracy. Sponsored by The Optical Society (OSA), the IEEE Communications Society and the IEEE Photonics Society, OFC is the largest global conference and exposition for optical communications and networking professionals.
On Sunday, March 9, Monga is one of five speakers at a workshop on “Does SDN (Software Defined Networking) Spell the End for GMPLS (Generalized Multi-Protocol Label Switching)?”
On Monday, March 10, Monga is one of two speakers in a panel discussion on “Why are Non-Carriers Building Their Own Networks?” as part of the OSA Executive Forum , an event for business leaders in networking and communications technology.
On Tuesday, May 11, he will be one of three speakers in a session on “Advancing Optical Solutions in Cloud Computing, Communications and Networking.
On Wednesday, March 12, Tracy will present “When Routers are Masters of Colored Light” as part of a panel discussion on “Packet Optical Convergence.”
ESnet’s Greg Bell, Inder Monga to Speak at 2014 ON*VECTOR Workshop
ESnet Director Greg Bell and ESnet Chief Technologist Inder Monga are among the invited speakers at the 2014 ON*VECTOR Workshop sponsored by NTT Network Innovation Laboratories. The workshop, hosted by the California Institute for Telecommunications and Information Technology (Calit2) at UC San Diego, will be held Wednesday and Thursday, March 5-6.
The annual, by-invitation-only workshop brings together leading networking experts from the research community and industry. In a session covering 40/100 Gbps networking, Bell will discuss ESnet’s 100G Transatlantic Testbed Architecture. As part of a session on next-generation architectures, Monga will give a summary of the report from a workshop he organized on behalf of the National Science Foundation on software defined networking.
ON*VECTOR, or Optical Networked Virtual Environments for Collaborative Trans-Oceanic Research is a joint project of NTT Network Innovation Laboratories, Keio University’s Institute for Digital Media and Content (DMC), the University of Tokyo’s Morikawa Laboratory, the University of Illinois at Chicago’s Electronic Visualization Laboratory, and the California Institute for Telecommunications and Calit2.
This Week's CS Seminars
Proposed Fault Tolerance for MPI-4
Tuesday, March 4, 9:30am – 10:30am, Bldg. 50A, Room 5132
Wesley Bland, Argonne National Laboratory
Up to now, the MPI Standard has included minimal mechanisms to handle process failure, something which is expected to become an even more critical problem as machine sizes grow. Now, the fault tolerance working group is proposing new additions that will facilitate stabilizing the MPI library and allowing applications to continue after process failure without restarting the entire job. This talk will give an overview of the proposed changes to the MPI Standard to include fault tolerance recovery mechanisms. It will cover the API changes and the rationale behind them as well as providing some examples of usage of the new mechanisms. The goal of the talk is to solicit responses from potential users before standardizing this proposal, so feel free to come with questions, suggestions, complaints, etc.
NWChem: Quantum chemistry across spatial, energy, and time (to solution) scales
Wednesday, March 5, 11am – 12pm, Bldg. 50F, Room 1647
Karol Kowalski, WR Wiley Environmental Molecular Sciences Laboratory and Pacific Northwest National Laboratory
In this presentation we will discuss the development of scalable and unique computational chemistry capabilities for modeling and simulation in NWChem, and we will demonstrate its performance on large scale computing platforms. NWChem is DOE’s premier quantum chemistry software developed at the Environmental Molecular Science Laboratory at Pacific Northwest National Laboratory, and is available to the scientific community through the open-source Educational Community License. We will discuss several new parallel algorithms for many-body methodologies, which are capable of taking advantage of existing petascale architectures. Special emphasize will be given to the novel algorithms which can utilize the aggregate power of heterogeneous computer architectures.
A Moving-Mesh Technique together With Data Assimilation for Simulating Glaciers and Ice Sheets
Wednesday, March 5, 3:30pm - 4:30pm, 939 Evans Hall - UC Berkeley Campus
Nancy Nichols, University of Reading, United Kingdom
Although the mathematics of ice sheet dynamics is well-established, the prediction of profiles and grounding movement are analytically infeasible and numerically difficult to achieve. Here we present a new ‘moving-mesh’ approach to simulating ice sheets and glaciers computationally that is driven by ice diffusion movement and successfully reproduces the features of ice-flow, including advance and retreat. The method is applied to a shallow ice model of a glacier using data from one of the EISMINT test cases and the results are compared. We then show how assimilation of measured data can be used within the moving framework to improve the prediction of ice sheet movement. We develop a procedure for treating the mesh point positions, together with the ice thickness, as unknown state variables within the assimilation system. The correlation between the unknown mesh positions and the ice thickness is approximated by a simple correlation function that provides flow dependent co-variances. We demonstrate the success of the technique for noisy, very infrequent, partial measurements of ice thickness, both with and without noisy measurements of the position of the flow boundary.
Link of the Week: Catching Particle Fever
After a year of film festival showings, the much-anticipated Particle Fever finally opens in theaters this Wednesday, March 5. The documentary by physicist-turned-filmmaker Mark Levinson tells the very human story of the search for the Higgs boson at the world's largest and most expensive physics experiment, the Large Hadron Collider at CERN. Some of the premiers offer a Q&A with Levinson and others involved in the project. See the film's web site (particlefever.com) form more information as well as the official trailer, clips, and downloads. »Learn More.