Scott P. Swerdlin

The Operational Mesogamma-Scale Analysis and Forecast System of the U.S. Army Test and Evaluation Command. Part I: Overview of the Modeling System, the Forecast Products, and How the Products Are Used

Given the rapid increase in the use of operational mesoscale models to satisfy different specialized needs, it is important for the community to share ideas and solutions for meeting the many associated challenges that encompass science, technology, education, and training. As a contribution toward this objective, this paper begins a series that reports on the characteristics and performance of an operational mesogammascale weather analysis and forecasting system that has been developed for use by the U.S. Army Test and Evaluation Command. During the more than five years that this four-dimensional weather system has been in use at seven U.S. Army test ranges, valuable experience has been gained about the production and effective use of high-resolution model products for satisfying a variety of needs. This paper serves as a foundation for the rest of the papers in the series by describing the operational requirements for the system, the data assimilation and forecasting system characteristics, and the forecaster training that is required for the finescale products to be used effectively.

A Reanalysis System for the Generation of Mesoscale Climatographies

Abstract The use of a mesoscale model–based four-dimensional data assimilation (FDDA) system for generating mesoscale climatographies is demonstrated. This dynamical downscaling method utilizes the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5), wherein Newtonian relaxation terms in the prognostic equations continually nudge the model solution toward surface and upper-air observations. When applied to a mesoscale climatography, the system is called Climate-FDDA (CFDDA). Here, the CFDDA system is used for downscaling eastern Mediterranean climatographies for January and July. The downscaling method performance is verified by using independent observations of monthly rainfall, Quick Scatterometer (QuikSCAT) ocean-surface winds, gauge rainfall, and hourly winds from near-coastal towers. The focus is on the CFDDA system’s ability to represent the frequency distributions of atmospheric states in addition to time means. The verification of the month...

The Operational Mesogamma-Scale Analysis and Forecast System of the U.S. Army Test and Evaluation Command. Part II: Interrange Comparison of the Accuracy of Model Analyses and Forecasts

This study builds upon previous efforts to document the performance of the U.S. Army Test and Evaluation Command’s Four-Dimensional Weather Modeling System using conventional metrics. Winds, temperature, and specific humidity were verified for almost 15 000 forecasts at five U.S. Army test ranges using near-surface mesonet data. The primary objective was to use conventional metrics to characterize the degree to which forecast accuracy varies from range to range, within the diurnal cycle, with elapsed forecast time, and among the seasons. It was found that there are large interrange differences in forecast error, with larger errors typically associated with the ranges located near complex orography. Similarly, significant variations in accuracy were noted for different times in the diurnal cycle, but the diurnal dependency varied greatly among the ranges. Factor of 2 differences in accuracy were also found across the seasons.

THE PENTAGON SHIELD FIELD PROGRAM Toward Critical Infrastructure Protection

The Pentagon, and its 25,000+ occupants, represents a likely target for a future terrorist attack using chemical, biological, or radiological material released into the atmosphere. Motivated by this, a building-protection system, called Pentagon Shield, is being developed and deployed by a number of government, academic, and private organizations. The system consists of a variety of data-assimilation and forecast models that resolve processes from the mesoscale to the city scale to the building scale, and assimilate meteorological and contaminant data that are measured by remote and in situ sensors. This paper reports on a field program that took place in 2004 in the area of the Pentagon, where the aim was to provide meteorological data and concentration data from tracer releases, and to support the development and evaluation of the system. In particular, the results of the field program are being used to improve our understanding of urban meteorological processes, verify the overall effectiveness of the ...

A Rapidly Deployable Operational Mesoscale Modeling System for Emergency-Response Applications

An operational mesoscale model–based forecasting system has been developed for use by U.S. Army Test and Evaluation Command meteorologists in their support of test-range operations. This paper reports on the adaptation of this system to permit its rapid deployment in support of a variety of civilian and military emergency-response applications. The innovation that allows for this rapid deployment is an intuitive graphical user interface that permits a non-expert to quickly configure the model for a new application, and launch the forecast system to produce operational products without further intervention. The graphical interface is Web based and can be run on a wireless laptop or a personal digital assistant in the field. The instructions for configuring the modeling system are transmitted to a compute engine [generally a personal computer (PC) cluster], and forecast products are placed on a Web site that can be accessed by emergency responders or other forecast users. This system has been used operation...

Climatologies Based on the Weather Research and Forecast (WRF) Model

Because tests at Army Test and Evaluation Command (ATEC) ranges can often only be conducted under specific atmospheric conditions, climatologies of each range could be a very useful tool for long-range test planning. Such datasets can provide the probability density function of near-surface wind speed, percent cloud cover, temperature, precipitation, turbulence intensity, upper-atmospheric wind speed, etc., as a function of the month of the year, time of day, and location on the range. The STAR Institute with guidance from the Ohio Supercomputer Center is working on porting the Climate Four Dimensional Data Assimilation (CFDDA) technology developed by the National Center for Atmospheric Research to version 3 of the Weather and Research Forecast (WRF) model for use on systems within the Department of Defense High Performance Computing Modernization Prograf m. The fully parallelized WRF-CFDDA system uses data-assimilation by Newtonian relaxation, to generate a regional reanalysis that is consistent with both observations and model dynamics for every hour of the past 20 years, at fine scales (3 km grid) over the Dugway Proving Ground range.

An Operational Mesoscale Ensemble-Based Forecast System using HPC Resources

The US Army Test and Evaluation Command (ATEC) currently is responsible for providing operational meteorological support to research, development, test, and evaluation (RDT&E) activities at eight Army installations. The four-dimensional weather (4DWX) meteorological support system used to provide that support was developed by the National Center for Atmospheric Research (NCAR) in collaboration with ATEC meteorologists. A high-resolution (mesoscale) numerical weather prediction (NWP) model is a major 4DWX component in operational use at seven ATEC test centers. This paper describes current 4DWX NWP capabilities and discusses how the new Department of Defense (DoD) dedicated high performance computing project investment (DHPI) at Dugway proving ground (DPG) will enhance NWP forecast support to ATEC field and virtual tests.