The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies with numerical weather prediction. In the fall of 1999, OMEGA was used for the first time to examine the structure and evolution of a hurricane (Floyd, 1999). The first simulation of Floyd was conducted in an operational forecast mode; additional simulations exploiting both the static as well as the dynamic grid adaptation options in OMEGA were performed later as part of a sensitivity-capability study. While a horizontal grid resolution ranging from about 120 km down to about 40 km was employed in the operational run, resolutions down to about 15 km were used in the sensitivity study to explicitly model the structure of the inner core. All the simulations produced very similar storm tracks and reproduced the salient features of the observed storm such as the recurvature off the Florida coast with an average 48-h position error of 65 km. In addition, OMEGA predicted the landfall near Cape Fear, North Carolina, with an accuracy of less than 100 km up to 96 h in advance. It was found that a higher resolution in the eyewall region of the hurricane, provided by dynamic adaptation, was capable of generating better-organized cloud and flow fields and a well-defined eye with a central pressure lower than the environment by roughly 50 mb. Since that time, forecasts were performed for a number of other storms including Georges (1998) and six 2000 storms (Tropical Storms Beryl and Chris, Hurricanes Debby and Florence, Tropical Storm Helene, and Typhoon Xangsane). The OMEGA mean track error for all of these forecasts of 101, 140, and 298 km at 24, 48, and 72 h, respectively, represents a significant improvement over the National Hurricane Center (NHC) 1998 average of 156, 268, and 374 km, respectively. In a direct comparison with the GFDL model, OMEGA started with a considerably larger position error yet came within 5% of the GFDL 72-h track error. This paper details the simulations produced and documents the results, including a comparison of the OMEGA forecasts against satellite data, observed tracks, reported pressure lows and maximum wind speed, and the rainfall distribution over land.
Twenty years ago, the multidimensional, positive deÿnite, advection transport algorithm was introduced by Smolarkiewicz. Over the two decades since, it has been applied countless times to numerous problems, however almost always on rectilinear grids. One of the few exceptions is the Operational Multiscale Environment model with Grid Adaptivity (OMEGA), an atmospheric simulation system originally designed to simulate atmospheric dispersion in the planetary boundary layer, but since then used for both mesoscale (from meso-to meso-) dispersion and weather forecasting. One of the unique aspects of OMEGA is the triangular unstructured grid geometry which leads in a natural way to the creation of a global grid with continuously variable resolution from roughly 100 km over the oceans to less than 10 km over regions of interest. Another unique aspect is the concept of dynamically adapting grid resolution-sometimes also called solution-adaptive grid resolution. A central element of the modelling system, however, is its advection solver-MPDATA. This paper presents the implementation of MPDATA on an unstructured grid and demonstrates its accuracy and e ciency using analytic and idealized test cases.
Rapid cycle genomic selection (RC-GS) helps to shorten the breeding cycle and reduce the costs of phenotyping, thereby increasing genetic gains in terms of both cost and time. We implemented RC-GS on two multi-parent yellow synthetic (MYS) populations constituted by intermating ten elite lines involved in each population, including four each of drought and waterlogging tolerant donors and two commercial lines, with proven commercial value. Cycle 1 (C 1) was constituted based on phenotypic selection and intermating of the top 5% of 500 S 2 families derived from each MYS population, test-crossed and evaluated across moisture regimes. C 1 was advanced to the next two cycles (C 2 and C 3) by intermating the top 5% selected individuals with high genomic estimated breeding values (GEBVs) for grain yield under drought and waterlogging stress. To estimate genetic gains, population bulks from each cycle were test-crossed and evaluated across locations under different moisture regimes. Results indicated that the realised genetic gain under drought stress was 0.110 t ha −1 yr −1 and 0.135 t ha −1 yr −1 , respectively, for MYS-1 and MYS-2. The gain was less under waterlogging stress, where MYS-1 showed 0.038 t ha −1 yr −1 and MYS-2 reached 0.113 t ha −1 yr −1. Genomic selection for drought and waterlogging tolerance resulted in no yield penalty under optimal moisture conditions. The genetic diversity of the two populations did not change significantly after two cycles of GS, suggesting that RC-GS can be an effective breeding strategy to achieve high genetic gains without losing genetic diversity.
By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3) have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system and presents the integrated CATS-OMEGA system as a prototype of such a system that has been used successfully in a number of different situations.
Aim:The objective of the study was to evaluate the effect of deep litter housing and fermented feed on carcass characteristics and meat quality of crossbred Hampshire pigs.Materials and Methods:Forty-eight weaned crossbred Hampshire piglets of 2 months age (24 males and 24 females) were selected for the experiment. The piglets were randomly assigned into 4 homogenous experimental groups with 6 males and 6 females each: E1; reared on a conventional housing and fed with a fermented diet, E2; reared on a deep litter housing system and fed with a fermented diet, E3; reared on a deep litter housing system and fed with a conventional diet and C; reared on a conventional housing system and fed with a conventional diet. The study was continued up to 32 weeks of age and at the end of this period, 6 animals (3 males and 3 females) from each experimental group were slaughtered to evaluate carcass traits and meat quality characteristics.Results:Pre-slaughter weight, hot carcass weight, and dressing percentage were significantly (p<0.01) affected by feeding fermented diet and deep litter housing while carcass traits, i.e., carcass length, backfat thickness, and loin eye area were not affected. The edible offal; liver and heart weight (p<0.05) differed significantly while kidney weight showed no difference. The inedible offal; head weight (p<0.01) and lung weight revealed a significant difference (p<0.05) while spleen and stomach weight showed no difference among the experimental groups. The wholesale cuts and meat: bone ratio of pigs also differed significantly among the groups. Morphometry of small and large intestine also showed a significant difference. Chemical composition of pork viz., moisture and total ash content was influenced by the treatment, while crude protein and ether extract content were not affected. Mineral composition of pork also showed no significant difference. Color characteristics of Longissimus dorsi muscle showed a significant difference in L* and a* value while parameter b* was not affected. The tenderness of meat showed significant difference among the groups (p<0.01).Conclusion:Crossbred Hampshire pigs being reared on fermented feed and deep litter housing could produce highlygraded carcass and improvement in meat quality.
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