IMAGe research: New algorithms, tools, and geophysical models




		A precipitation atlas overlaid with scenes from the July 1997 Fort Collins, Colorado flood where 10 inches of rain fell on the city in 6 hours. Despite common descriptions of future climate change as "global warming," extreme precipitation events driven by climate change also have large economic and ecological impacts. Statistical methods being developed in IMAGe are allowing modelers to refine the accuracy of their estimates of past climate and enhance their ability to project future weather and climate events. (Photos by John Weaver.)


		A newer type of precipitation atlas is overlaid on an exaggerated topographical isosurface of the Colorado Front Range showing Fort Collins at the top. The data for this figure is based on extrapolating daily precipitation data from the weather stations located at the black and gray markers. Elevation is shown using perspective and shading, and the different colors represent an extreme amount of precipitation expected to occur in a 24-hour period on average once every 20 years. For example, the red color around Fort Collins correlates to a value of less than 2.5, indicating an extreme rainfall event of approximately 2.5 inches in a 24-hour period about every 20 years. This can also be interpreted as a 5 percent chance per year that Fort Collins will receive 2.5 inches of rain in 24 hours. This kind of information is important for flood planning and designing roads and other permanent structures.

The power of mathematical science is that similar methods and models can be used to solve problems in very different contexts. The Institute of Mathematics Applied to Geosciences (IMAGe) was formed in October 2004 to develop tools, methods, and models that can address some of NCAR's fundemental science problems. IMAGe is also actively introducing the mathematics community to new problems that are posed by geophysical processes and observations. Two important vehicles that support this interdisciplinary activity are the Theme of the Year workshops and publically available software for numerical and statistical methods. IMAGe contributes to the NCAR strategic priorities of "Conducting research in computer science, applied mathematics, statistics, and numerical methods" and "Engaging a broader and more diverse community."

Some accomplishments during FY2007 include multi-scale models for the complex structures produced by fluid flow, statistical models for analyzing regional climate model output, and developing methods to match parameters in large geophysical models to observations. Each of these projects is complemented by publically available software that makes these advances accessible to the research community. The FY2007 Theme of the Year (TOY) was a successful series of three workshops on statistics and numerical models that brought together students, faculty, modelers, and statisticians. This TOY featured a summer school that established connections between students from a diverse range of backgrounds as they learned about models and methods for understanding the Earth's carbon cycle.

In FY2008, IMAGe will develop:

Extensions to adaptive alogrithms for simulating magnetohydrodynamical flow
New numerical methods that are conservative, high order, and scale to large numbers of processors
Methods for synthesizing different kinds of climate proxy data to estimate past climate and for summarizing multi-model regional climate experiments
Data assimiliation methods for tracing sources and sinks of atmospheric constituents

The 2008 TOY will bring modelers together with mathematicians and statisticians to study geophysical turbulence phenomena. This effort recognizes NCAR's longstanding interest in turbulence as a foundation for understanding the dynamics of the atmosphere and ocean. It will be codirected by Keith Julien (Applied Mathematics CU) and is in partnership with the Institute for Pure and Applied Mathematics at UCLA. This thematic program will consist of three workshops that span turbulence theory, observations, and computation. A summer school will revisit these three lines of research from the workshops, bring new talent into this field, and foster multi-disciplinary perspectives.