The Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) Program: Observations and Results

Weather predictability in complex terrain continues to lag predictability over simple topography. Physical, thermodynamic, and numerical issues unique to complex terrain can exacerbate issues already common to weather prediction. An understanding of both the local thermally-driven flows and the interaction of synoptic-scale disturbances with the terrain is critical to improving predictability in mountainous areas. Also, characterizing the atmospheric boundary layer in complex terrain offers many challenges, including but not limited to sub-grid scale phenomena that are critical to accurate mesoscale modeling. Parameterizations of such processes, reducing model errors and their growth, model validations and new technologies for measurements are some of the overarching issues that need to be addressed in improving weather predictions in mountainous terrain. To this end, the MATERHORN program was conceived in response to the 2011 Multidisciplinary University Research Initiative (MURI) of the Department of Defense to address scientific issues akin to mountain weather. The participants include the University of Notre Dame, Naval Post Graduate School, University of California at Berkeley, University of Utah, University of Virginia, Naval Research Laboratory, US Army Dugway Proving Ground (DPG) and the Army Research Laboratory. Two comprehensive month-long field experimental components (MATERHORN-X) were conducted at the Granite Mountain Atmospheric Science Test Bed (GMAST) of DPG in October 2012 and May 2013. Observations from the two field experiments and results from both the experimental and modeling groups will be presented here.