From aaulia@sciences.sdsu.edu Sat Jan 12 22:45:39 2008 From: aaulia@sciences.sdsu.edu (aaulia@sciences.sdsu.edu) Date: Sat, 12 Jan 2008 17:45:39 -0500 Subject: [compsci] COLLOQUIUM: GLOBAL MONITORING OF PARTICULATE ORGANIC CARBON USING SATELLITE OCEAN COLOR OBSERVATIONS Message-ID: <380-220081612224539473@M2W012.mail2web.com> Title: GLOBAL MONITORING OF PARTICULATE ORGANIC CARBON USING SATELLITE OCEAN COLOR OBSERVATIONS Date: Friday, January 18th, 2008 Time: 3:30 pm Location: GMCS 214 Speaker: Malgorzata Stramska Modeling Ecosystems Dynamics Group CHORS and CSRC San Diego State University Abstract: The development of bio-optical algorithms linking measurable optical properties to Chla has been the focus of numerous studies over the last three decades. These algorithms and the successful operation of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) on OrbView-2 satellite since 1997, allowed for the fact that the multi-year global time series data on ocean surface chlorophyll a concentrations (Chl) with excellent temporal coverage have become available. Although such satellite-based Chl estimates are subject to some uncertainty (nominal accuracy goal of 30%), they have become an invaluable research tool for studying phytoplankton biomass of ocean waters. However, for studies of ocean biogeochemistry and its potential role in climate it is carbon, not chlorophyll, which is of most direct interest. The particulate organic carbon (POC) pool in the surface ocean, which includes autotrophic and heterotrophic organisms and biogenic detrital particles, represents one of carbon reservoirs of substantial interest. Sinking of POC from surface waters is part of the biological pump that provides a mechanism for storing carbon in the deep ocean and a long-term sink for atmospheric CO2. Satellite capabilities to monitor changes in particulate carbon pools can effectively aid in studies related to global carbon cycling and the role of the biological pump in the ocean. This is why we have proposed to develop ocean color POC algorithms. In this presentation I will show a summary of our recent work where we have examined several approaches for estimating the surface concentration of particulate organic carbon, POC, from optical measurements of remote-sensing reflectance, Rrs(l). The best error statistics were found for power function fits to the data of POC vs. Rrs(443)/Rrs(555) and POC vs. Rrs(490)/Rrs(555). For the data set collected by us, which includes over 50 data pairs, these relationships are characterized by the mean normalized bias of about 2% and the normalized root mean square error of about 20%. We recommended that these algorithms be implemented for routine NASA processing of ocean color satellite data to produce global maps of surface ocean POC with the status of an evaluation data product for continued work on algorithm development and refinements. In this presentation I will also discuss our future plans to use satellite derived POC maps to study oceanic POC budgets and fluxes. Host: Jose Castillo For future events, please visit our web site at: http://www.csrc.sdsu.edu/csrc/events/colloquium/ ******************************************* Akmal Aulia PhD Student Computational Science Research Center San Diego State University Phone: 619-335-7187 Email: aaulia@sciences.sdsu.edu _______________________________________________ SDSU Computational Science Research Center Mailing List -------------------------------------------------------------------- myhosting.com - Premium Microsoft® Windows® and Linux web and application hosting - http://link.myhosting.com/myhosting From aaulia@sciences.sdsu.edu Wed Jan 16 16:39:22 2008 From: aaulia@sciences.sdsu.edu (aaulia@sciences.sdsu.edu) Date: Wed, 16 Jan 2008 11:39:22 -0500 Subject: [compsci] *Reminder* COLLOQUIUM: GLOBAL MONITORING OF PARTICULATE ORGANIC CARBON USING SATELLITE OCEAN COLOR OBSERVATIONS Message-ID: <380-220081316163922807@M2W026.mail2web.com> Title: GLOBAL MONITORING OF PARTICULATE ORGANIC CARBON USING SATELLITE OCEAN COLOR OBSERVATIONS Date: Friday, January 18th, 2008 Time: 3:30 pm Location: GMCS 214 Speaker: Malgorzata Stramska Modeling Ecosystems Dynamics Group CHORS and CSRC San Diego State University Abstract: The development of bio-optical algorithms linking measurable optical properties to Chla has been the focus of numerous studies over the last three decades. These algorithms and the successful operation of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) on OrbView-2 satellite since 1997, allowed for the fact that the multi-year global time series data on ocean surface chlorophyll a concentrations (Chl) with excellent temporal coverage have become available. Although such satellite-based Chl estimates are subject to some uncertainty (nominal accuracy goal of 30%), they have become an invaluable research tool for studying phytoplankton biomass of ocean waters. However, for studies of ocean biogeochemistry and its potential role in climate it is carbon, not chlorophyll, which is of most direct interest. The particulate organic carbon (POC) pool in the surface ocean, which includes autotrophic and heterotrophic organisms and biogenic detrital particles, represents one of carbon reservoirs of substantial interest. Sinking of POC from surface waters is part of the biological pump that provides a mechanism for storing carbon in the deep ocean and a long-term sink for atmospheric CO2. Satellite capabilities to monitor changes in particulate carbon pools can effectively aid in studies related to global carbon cycling and the role of the biological pump in the ocean. This is why we have proposed to develop ocean color POC algorithms. In this presentation I will show a summary of our recent work where we have examined several approaches for estimating the surface concentration of particulate organic carbon, POC, from optical measurements of remote-sensing reflectance, Rrs(l). The best error statistics were found for power function fits to the data of POC vs. Rrs(443)/Rrs(555) and POC vs. Rrs(490)/Rrs(555). For the data set collected by us, which includes over 50 data pairs, these relationships are characterized by the mean normalized bias of about 2% and the normalized root mean square error of about 20%. We recommended that these algorithms be implemented for routine NASA processing of ocean color satellite data to produce global maps of surface ocean POC with the status of an evaluation data product for continued work on algorithm development and refinements. In this presentation I will also discuss our future plans to use satellite derived POC maps to study oceanic POC budgets and fluxes. Host: Jose Castillo For future events, please visit our web site at: http://www.csrc.sdsu.edu/csrc/events/colloquium/ ******************************************* Akmal Aulia PhD Student Computational Science Research Center San Diego State University Phone: 619-335-7187 Email: aaulia@sciences.sdsu.edu _______________________________________________ SDSU Computational Science Research Center Mailing List -------------------------------------------------------------------- mail2web.com – What can On Demand Business Solutions do for you? http://link.mail2web.com/Business/SharePoint From aaulia@sciences.sdsu.edu Sat Jan 19 01:03:44 2008 From: aaulia@sciences.sdsu.edu (aaulia@sciences.sdsu.edu) Date: Fri, 18 Jan 2008 20:03:44 -0500 Subject: [compsci] COLLOQUIUM: MEETING THE CHALLENGES OF THE 21ST CENTURY EARTH SYSTEM MODELING AT THE PETASCALE AND BEYOND Message-ID: <380-2200816191344489@M2W022.mail2web.com> Title: MEETING THE CHALLENGES OF THE 21ST CENTURY EARTH SYSTEM MODELING AT THE PETASCALE AND BEYOND Date: Friday, January 25th, 2008 Time: 3:30 pm Location: GMCS 214 Speaker: Rich Loft Director of Technology Development Computational and Information Systems Laboratory National Center for Atmospheric Research Abstract: Dramatic improvements in computing power, along with rapid advances in disk capacity, tape densities and network bandwidths, are transforming how our society generates and consumes information. Earth system science is no exception. The availability of observational data about our planet in digital form, coupled with once-unimaginable computer modeling capabilities, has allowed geoscientists to tackle a broad front of complex, interdisciplinary, grand challenge problems in new and more realistic ways. For example, climate scientists, once confined to low-resolution simulations using atmospheric general circulation models with prescribed sea surface temperatures, now work with fully dynamically coupled models of sea ice, ocean and land surface processes. In the future, additional processes, such as ocean and atmospheric chemistry, dynamic vegetation, and the carbon cycle will be included, and resolution dramatically increased. Trends toward increased interdisciplinarity and complexity are recapitulated across many grand challenge problems in computational geoscience, ranging from space weather to modeling subsurface fluid flow. The feasibility of deploying advanced models to tackle these problems is complicated by two factors: first, the architectural trends of supercomputing systems, which point towards increased levels of parallelism, and second, for such systems to be useful, scientists from many disciplines, distributed across many institutions, will need to share vast amounts of data seamlessly. Realizing this vision of integrated distributed cyberinfrastructure for geoscience research is no simple task. The talk will show the progress made to date, by NCAR and other institutions, to meet these challenges through improvements in application scalability, development of distributed data federation systems, and the creation of national-scale grids for high performance computing such as the TeraGrid. Finally, to accomplish these ambitious goals, the next generation of scientists and engineers must be inspired, educated and trained. Programs and opportunities at NCAR designed to introduce students to applied mathematics, high performance computing, and computational geoscience will be presented. Host: Ricardo Carretero For future events, please visit our web site at: http://www.csrc.sdsu.edu/csrc/events/colloquium/ ******************************************* Akmal Aulia PhD Student Computational Science Research Center San Diego State University Phone: 619-335-7187 Email: aaulia@sciences.sdsu.edu _______________________________________________ SDSU Computational Science Research Center Mailing List -------------------------------------------------------------------- mail2web.com - Microsoft® Exchange solutions from a leading provider - http://link.mail2web.com/Business/Exchange From aaulia@sciences.sdsu.edu Wed Jan 23 00:03:27 2008 From: aaulia@sciences.sdsu.edu (aaulia@sciences.sdsu.edu) Date: Tue, 22 Jan 2008 19:03:27 -0500 Subject: [compsci] *Reminder* COLLOQUIUM: MEETING THE CHALLENGES OF THE 21ST CENTURY EARTH SYSTEM MODELING AT THE PETASCALE AND BEYOND Message-ID: <380-2200813230327835@M2W011.mail2web.com> Title: MEETING THE CHALLENGES OF THE 21ST CENTURY EARTH SYSTEM MODELING AT THE PETASCALE AND BEYOND Date: Friday, January 25th, 2008 Time: 3:30 pm Location: GMCS 214 Speaker: Rich Loft Director of Technology Development Computational and Information Systems Laboratory National Center for Atmospheric Research Abstract: Dramatic improvements in computing power, along with rapid advances in disk capacity, tape densities and network bandwidths, are transforming how our society generates and consumes information. Earth system science is no exception. The availability of observational data about our planet in digital form, coupled with once-unimaginable computer modeling capabilities, has allowed geoscientists to tackle a broad front of complex, interdisciplinary, grand challenge problems in new and more realistic ways. For example, climate scientists, once confined to low-resolution simulations using atmospheric general circulation models with prescribed sea surface temperatures, now work with fully dynamically coupled models of sea ice, ocean and land surface processes. In the future, additional processes, such as ocean and atmospheric chemistry, dynamic vegetation, and the carbon cycle will be included, and resolution dramatically increased. Trends toward increased interdisciplinarity and complexity are recapitulated across many grand challenge problems in computational geoscience, ranging from space weather to modeling subsurface fluid flow. The feasibility of deploying advanced models to tackle these problems is complicated by two factors: first, the architectural trends of supercomputing systems, which point towards increased levels of parallelism, and second, for such systems to be useful, scientists from many disciplines, distributed across many institutions, will need to share vast amounts of data seamlessly. Realizing this vision of integrated distributed cyberinfrastructure for geoscience research is no simple task. The talk will show the progress made to date, by NCAR and other institutions, to meet these challenges through improvements in application scalability, development of distributed data federation systems, and the creation of national-scale grids for high performance computing such as the TeraGrid. Finally, to accomplish these ambitious goals, the next generation of scientists and engineers must be inspired, educated and trained. Programs and opportunities at NCAR designed to introduce students to applied mathematics, high performance computing, and computational geoscience will be presented. Host: Ricardo Carretero For future events, please visit our web site at: http://www.csrc.sdsu.edu/csrc/events/colloquium/ ******************************************* Akmal Aulia PhD Student Computational Science Research Center San Diego State University Phone: 619-335-7187 Email: aaulia@sciences.sdsu.edu _______________________________________________ SDSU Computational Science Research Center Mailing List -------------------------------------------------------------------- mail2web - Check your email from the web at http://link.mail2web.com/mail2web From aaulia@sciences.sdsu.edu Sat Jan 26 02:07:12 2008 From: aaulia@sciences.sdsu.edu (aaulia@sciences.sdsu.edu) Date: Fri, 25 Jan 2008 21:07:12 -0500 Subject: [compsci] COLLOQUIUM: ACTION POTENTIALS AS PROPAGATING DENSITY PULSES AND THE ROLE OF ANESTHETICS Message-ID: <380-2200816262712877@M2W035.mail2web.com> Title: ACTION POTENTIALS AS PROPAGATING DENSITY PULSES AND THE ROLE OF ANESTHETICS Date: Friday, February 1st, 2008 Time: 3:30 pm Location: GMCS 214 Speaker: Thomas Heimburg Membrane Biophysics Group Niels Bohr Institute University of Copenhagen Abstract: The action of nerves has been one of the first topics of interest in biophysics. Important physicists like Galvani, Volta and Helmholtz were among the first to study nerve pulse propagation. Nevertheless, there still seems to be a communication barrier between molecular biology and physics. Many models in biology contradict the intuition of a physicist when it comes to the consideration of length and time scales, or to the use and interpretation of physical variables. For the example of nerve pulses and anesthesia it is shown that straightforward application of thermodynamics may provide considerable insight into these seemingly complicated processes. Biological membranes display order transitions close to temperatures of physiological interest. This feature leads to the possibility of density pulse (soliton) propagation in such membranes. We discuss the propagating pulses in the context of several striking properties of nerve membranes under the influence of nerve pulses, including mechanical dislocations and temperature changes. We relate it to the famous but so far unexplained Meyer-Overton rule stating that the effectiveness of an anesthetic is proportional to its membrane solubility. Anesthesia may find an explanation in the well-known general phenomenon of freezing point depression. Host: Peter Salamon For future events, please visit our web site at: http://www.csrc.sdsu.edu/csrc/events/colloquium/ ******************************************* Akmal Aulia PhD Student Computational Science Research Center San Diego State University Phone: 619-335-7187 Email: aaulia@sciences.sdsu.edu _______________________________________________ SDSU Computational Science Research Center Mailing List -------------------------------------------------------------------- mail2web.com - Microsoft® Exchange solutions from a leading provider - http://link.mail2web.com/Business/Exchange From aaulia@sciences.sdsu.edu Wed Jan 30 19:26:41 2008 From: aaulia@sciences.sdsu.edu (aaulia@sciences.sdsu.edu) Date: Wed, 30 Jan 2008 14:26:41 -0500 Subject: [compsci] *Reminder* COLLOQUIUM: ACTION POTENTIALS AS PROPAGATING DENSITY PULSES AND THE ROLE OF ANESTHETICS Message-ID: <380-220081330192641430@M2W042.mail2web.com> Title: ACTION POTENTIALS AS PROPAGATING DENSITY PULSES AND THE ROLE OF ANESTHETICS Date: Friday, February 1st, 2008 Time: 3:30 pm Location: GMCS 214 Speaker: Thomas Heimburg Membrane Biophysics Group Niels Bohr Institute University of Copenhagen Abstract: The action of nerves has been one of the first topics of interest in biophysics. Important physicists like Galvani, Volta and Helmholtz were among the first to study nerve pulse propagation. Nevertheless, there still seems to be a communication barrier between molecular biology and physics. Many models in biology contradict the intuition of a physicist when it comes to the consideration of length and time scales, or to the use and interpretation of physical variables. For the example of nerve pulses and anesthesia it is shown that straightforward application of thermodynamics may provide considerable insight into these seemingly complicated processes. Biological membranes display order transitions close to temperatures of physiological interest. This feature leads to the possibility of density pulse (soliton) propagation in such membranes. We discuss the propagating pulses in the context of several striking properties of nerve membranes under the influence of nerve pulses, including mechanical dislocations and temperature changes. We relate it to the famous but so far unexplained Meyer-Overton rule stating that the effectiveness of an anesthetic is proportional to its membrane solubility. Anesthesia may find an explanation in the well-known general phenomenon of freezing point depression. Host: Peter Salamon For future events, please visit our web site at: http://www.csrc.sdsu.edu/csrc/events/colloquium/ ******************************************* Akmal Aulia PhD Student Computational Science Research Center San Diego State University Phone: 619-335-7187 Email: aaulia@sciences.sdsu.edu _______________________________________________ SDSU Computational Science Research Center Mailing List -------------------------------------------------------------------- mail2web.com – What can On Demand Business Solutions do for you? http://link.mail2web.com/Business/SharePoint