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| Speaker/Affiliation | Title | Abstract |
|---|---|---|
Matthew Long
Matthew Long <mclong@ucar.edu> | MARBL talk: Ocean biogeochemistry in the Earth system modeling framework: applications and approach | Marine biogeochemical cycles play a fundamental role regulating climate, most directly through impacts on atmospheric carbon dioxide. This has motivated the development of ocean biogeochemistry modules as components of Earth system models, primarily for the purpose of simulating changes in ocean sinks for carbon dioxide under future emissions scenarios. These models, however, can be applied to a range of other interesting problems related to marine ecology and biogeochemistry. In this talk, I provide a brief overview of some research questions in ocean biogeochemistry and ecology that I find interesting. I then describe our efforts to develop the Marine Biogeochemistry Library (MARBL), which is a modular implementation of ocean biogeochemistry that aims to be flexible and capable of operating within different physical frameworks---thereby enabling research across a broad array of questions. |
Michal A. Kopera (UCSC), Wieslaw Maslowski (NPS), Francis X. Giraldo (NPS)
Michal A. Kopera <makopera@ucsc.edu> | A new ice sheet / ocean interaction model for Greenland Fjords using discontinuous Galerkin method | One of the key outstanding challenges in modeling of climate change and sea-level rise is the ice-sheet/ocean interaction in narrow, elongated and often geometrically complicated fjords around Greenland. The goal of the Fjord-DG (FDG) project is to build a separate, highresolution module for use in Earth System Models (ESMs) to realistically represent the fjord bathymetry and coastlines and the fine-scale processes occurring within the fjord and at the ice shelf interface, using discontinuous Galerkin (DG) methods. FDG is currently at the first stage of development. We used NUMA (Non-hydrostatic Unified model of the Atmosphere) framework to develop the incompressible Navier-Stokes equation (INSE) solver, which will be used as a dynamical core in the fjord ocean model. We will present some preliminary results of idealized INSE test cases, and discuss further avenues of the project progress. The key features of the FDG module will be high-order accuracy, geometrical flexibility and nonconforming adaptive mesh refinement to resolve the processes occurring near the ice-sheet/ ocean interface without introducing prohibiting computational cost. The non-hydrostatic model will account for the stationary ice-shelf with sub-shelf ocean interaction, basal melting and subglacial meltwater influx, with boundary conditions at the surface to account for floating sea ice. The boundary conditions will be provided to the model via CPL7 coupler to emulate the integration with ESM. FDG will be tested initially on Sermilik Fjord using real bathymetry, boundary and initial conditions, and evaluated against observations and other model results for this fjord. The overarching goal of the project is to be able to resolve the ice-sheet/ocean interactions around the entire Greenland’s coast and two-way couple with climate models like ACME. |
Michael Prather, Juno Hso, Alex Viedenbaum, Alex Nicolau; UC Irvine Michael Prather [mailto:mprather@uci.edu] | Solar-J - RRTMG comparisons An examination of systematic biases in ACME solar heating rates - comparison with multi-stream Solar-J | As part of the development of a combined photolysis-heating module for DOE's ACME, we have taken the better-resolved photolysis code (Cloud-J, < 778 nm) and merged it with the RRTMG bins longward of 778 nm. For clear-sky calculations, the results are similar as expected, but for cirrus and stratus decks the 2-stream models in RRTMG produce significant biases that vary as a function of solar zenith angle and cloud optical depth when compared with the 8-stream Solar-J model. This is expected, but the size is significant, and may affect the mean meteorology. We present comparisons of the different options for solar heating codes used in CESM and ACME with those from the newly developed Solar-J. |