Climate models use quantitative methods to simulate the interactions of the atmosphere, oceans, land surface, and ice. They are used for a variety of purposes from study of the dynamics of the climate system to projections of future climate. NMC participates in research to improve the next generation of climate models by looking at the analysis and modeling of rotating stratified flows. NMC is also involved in modeling ocean currents and how ocean circulation models are used to understand the climate.
NMC research in climate change is also closely tied to our Plant Biology initiative. We investigate carbon dynamics, energy and nutrient exchange, and climate feedbacks within the global climate system based on molecular-to-cellular-to-plant-to-ecosystem science and modeling. The latest climate research at NMC includes:
Coherent Structures and Mixing in Rotating and Stratified Flows
Susan Kurien, NMC Affiliate Researcher, LANL Staff Scientist
This research aims to quantify the emergent length scales of coherent flow structures in rotating and stratified flows and relate those to the characteristic length scales over which mixing occurs. The coherent structures range from tall and columnar to flat and pancake-like, with characteristic vertical and horizontal sizes vary depending on the relative strengths of the rotation and stratification. The efficiency with which such flows mix a scalar, such as heat or mass density, into the flow will vary across the structures formed. This variation will be analyzed using statistical analysis of a series of large scale simulations with varying parameters of interest. The connection between intrinsic scale and mixing scales will be deduced as a function of the global parameters.
Energy Pathways and Scale Interactions in the Ocean
Hussein Aluie, NMC Affiliate Researcher, University of Rochester
The project would enable us to quantify the power (in Watts) being injected/extracted in different flow structures as well as identify the sources/sinks of such energy. This would constitute a fundamental intellectual advance in physical oceanography using a novel approach in fluid dynamics and nonlinear multiscale physics. The benefits to the science of climate prediction and uncertainty reduction can be very significant. The work would potentially unravel the scale-physics at play in the ocean, offer a priori constraints on parameter tuning of ocean parameterization schemes, and help in the development of a new class of parameterizations that are a function of geographic location and grid resolution, currently a major DOE thrust in ocean modeling and scientific computing.
Analysis and Modeling of Rotating Stratified Flows
The next generation of climate models will have access to ever more resolved simulations but will still need proper parameterization of the small scales. This project connects experts in applied mathematics and geophysics with massive high-performance computational resources from the DOE Office of Science INCITE program to approach the problem of parameterization comprehensively using theoretical and mathematical development, coupled with detailed numerical experiments. This approach is expected to result in a deeper understanding of the multiscale physics of geophysical flows and lead to practical parameterizations of unresolvable processes in models. Funding for this project comes from the National Science Foundation.
Global Surface Drifters and Sub-mesoscale Processes
Global Surface Drifters are buoys placed on the ocean that take observations of currents, sea surface temperature, atmospheric pressure, winds and salinity. Studies of the data from these satellite-tracked buoys revealed the presence of small-scale eddies possibly associated with the formation of barrier layers in ocean currents. This project focuses on the distribution and polarity of sub-mesoscale processes in the open ocean, and in particular in the subtropical South Atlantic Ocean. Funding for this project comes from the National Science Foundation.
The Role of Basin Modes in Pacing Pacific Decadal Variability
See the report: Normal Modes of the World Ocean
Global Energy Observatory
Rajan Gupta, NMC Affiliate Researcher, LANL Staff Scientist
The Global Energy Observatory (GEO) is a set of free interactive databases and tools built collaboratively through open source data. The goal of GEO is to promote an understanding, on a global scale, of the dynamics of change in energy systems, quantify emissions and their impacts, and accelerate the transition to carbon-neutral, environmentally benign energy systems while providing affordable energy to all. By providing easy to use and visualize data, models and analysis tools we aim to engage the public and the experts. Data in GEO can be edited from anywhere in the world.