Sensitivity Tests in the Dynamical and Thermal Part of the MRF-Urban PBL Scheme in the MM5 Model

2009 ◽  
pp. 87-94
Author(s):  
Aggeliki Dandou ◽  
Maria Tombrou
Keyword(s):  
Mm5 Model ◽  
Sensitivity Tests ◽  
Pbl Scheme ◽  
Thermal Part

scholarly journals Applying a Mesoscale Atmospheric Model to Svalbard Glaciers

2012 ◽  
Vol 2012 ◽  
pp. 1-22 ◽  
Author(s):  
Björn Claremar ◽  
Friedrich Obleitner ◽  
Carleen Reijmer ◽  
Veijo Pohjola ◽  
Anna Waxegård ◽  
...  
Keyword(s):  
Wind Speed ◽  
State Of The Art ◽  
Atmospheric Model ◽  
Wave Radiation ◽  
Vertical Resolution ◽  
Microphysics Scheme ◽  
Frequency Distributions ◽  
Sensitivity Tests ◽  
Pbl Scheme ◽  
Mesoscale Atmospheric Model

The mesoscale atmospheric model WRF is used over three Svalbard glaciers. The simulations are done with a setup of the model corresponding to the state-of-the-art model for polar conditions, Polar WRF, and it was validated using surface observations. The ERA-Interim reanalysis was used for boundary forcing and the model was used with three nested smaller domains, 24 and 8 km, and 2.7 km resolution. The model was used for a two-year period as well as for a more detailed study using 3 summer and winter months. In addition sensitivity tests using finer horizontal and vertical resolution in the boundary layer and using different physics schemes were performed. Temperature and incoming short- and long-wave radiation were skillfully simulated, with lower agreement between measured and modelled wind speed. Increased vertical resolution improved the frequency distributions of the wind speed and the temperature. The choice of different physics schemes only slightly changed the model results. The polar-optimized microphysics scheme outperformed a slightly simpler microphysics scheme, but the two alternative and more sophisticated PBL schemes improved the model score. A PBL scheme developed for very stable stratifications (QNSE) proved to be better in the winter.

scholarly journals Downslope windstorm in Iceland – WRF/MM5 model comparison

2011 ◽  
Vol 11 (1) ◽  
pp. 103-120 ◽  
Author(s):  
Ó. Rögnvaldsson ◽  
J.-W. Bao ◽  
H. Ágústsson ◽  
H. Ólafsson
Keyword(s):  
Model Comparison ◽  
Wrf Model ◽  
Horizontal Resolution ◽  
Equation Model ◽  
Moisture Distribution ◽  
Mm5 Model ◽  
Pbl Scheme ◽  
Lee Wave ◽  
Simulated Surface ◽  
Downslope Windstorms

Abstract. A severe windstorm downstream of Mt. Öræfajökull in Southeast Iceland is simulated on a grid of 1 km horizontal resolution by using the PSU/NCAR MM5 model and the Advanced Research WRF model. Both models are run with a new, two equation planetary boundary layer (PBL) scheme as well as the ETA/MYJ PBL schemes. The storm is also simulated using six different micro-physics schemes in combination with the MYJ PBL scheme in WRF, as well as one "dry" run. Output from a 3 km MM5 domain simulation is used to initialise and drive both the 1 km MM5 and WRF simulations. Both models capture gravity-wave breaking over Mt. Öræfajökull, while the vertical structure of the lee wave differs between the two models and the PBL schemes. The WRF simulated downslope winds, using both the MYJ and 2EQ PBL schemes, are in good agreement with the strength of the observed downslope windstorm. The MM5 simulated surface winds, with the new two equation model, are in better agreement to observations than when using the ETA scheme. Micro-physics processes are shown to play an important role in the formation of downslope windstorms and a correctly simulated moisture distribution is decisive for a successful windstorm prediction. Of the micro-physics schemes tested, only the Thompson scheme captures the downslope windstorm.

scholarly journals Downslope windstorm in Iceland – WRF/MM5 model comparison

2008 ◽  
Vol 8 (2) ◽  
pp. 6437-6468 ◽  
Author(s):  
Ó. Rögnvaldsson ◽  
J.–W. Bao ◽  
H. Ágústsson ◽  
H. Ólafsson
Keyword(s):  
Model Comparison ◽  
Wrf Model ◽  
Horizontal Resolution ◽  
Equation Model ◽  
Surface Winds ◽  
Mm5 Model ◽  
Pbl Scheme ◽  
Lee Wave ◽  
Simulated Surface ◽  
Downslope Windstorms

Abstract. A severe windstorm downstream of Mnt. Öræfajökull in Southeast Iceland is simulated on a grid of 1 km horizontal resolution by using the PSU/NCAR MM5 model and the Advanced Research WRF model. Both models are run with a new, two equation planetary boundary layer (PBL) scheme as well as the ETA/MYJ PBL schemes. The storm is also simulated using six different micro-physics schemes in combination with the MYJ PBL scheme in WRF. Output from a 3 km MM5 domain simulation is used to initialise and drive both the 1 km MM5 and WRF simulations. Both models capture gravity-wave breaking over Mnt. Öræfajökull, while the vertical structure of the lee wave differs between the two models and the PBL schemes. The WRF simulated downslope winds, using the MYJ PBL scheme, are in good agreement with the strength of the observed downslope windstorm, whilst using the new two equation scheme surface winds are considerably less than observed winds. The MM5 simulated surface winds, with the new two equation model, are in better agreement with observations than when using the ETA scheme. Micro-physics processes are shown to play an important role in the formation of downslope windstorms and lifting of the upslope isotherm layer from mountain height to about 1.3 times the mountain height leads to a significant increase in the downslope windstorm.

STUDY AND CHARACTERIZATION GROWTH OF FOUR MICROALGAE SPECIES AND TEST ANTIMICROBIAL ACTIVITY

Jurnal Zarah ◽  
2018 ◽  
Vol 6 (2) ◽  
pp. 53-58
Author(s):  
Marniati Salim
Keyword(s):  
Dunaliella Salina ◽  
Methanol Extract ◽  
Sea Water ◽  
Basal Medium ◽  
Nannochloropsis Oculata ◽  
Inhibitory Zone ◽  
Antimicrobial Sensitivity ◽  
Sensitivity Tests ◽  
Microalgae Biomass ◽  
Chaetoceros Calcitrans

Abstract In this study to the growth characteristics of microalgae (Dunaliella salina, Nannochloropsis oculata, Tetrasel mis chuii & Chaetoceros calcitrans), in different mediums, namely Bold’s Basal Medium (BBM) and BBM modification of sea water. The results obtained from microalgae (N.oculata, T.chuii, C.calcitrans) are better grown on BBM media while microlaga D.salina grows well on BBM modification of sea water. Microalgae biomass is extracted by maceration method in hexane and methanol solvents. Test bacteria used gram positive (Staphylococcus aureus) and gram negative (Escherichia coli). Inhibitory zone diameter results were compared with antimicrobial sensitivity tests according to Clinical and Laboratory Standards Institute (CLSI). From the results of microalgae hexane and methanol extract antibacterial activity tests (D.salina, N.oculata, T.chuii, C.calcitrans) showed that the extract was not too sensitive to inhibit bacterial growth.   Keywords: microalgae, medium, antimicrobial

The Effectiveness of Amoxicillin and Cefalexin in Two Species from Staphylococcus and Bacillus Isolated from Bovine Mastitis in Sudan

2019 ◽  
Author(s):  
Reem Rabie Mohammed Salih
Keyword(s):  
Bacillus Cereus ◽  
Bovine Mastitis ◽  
Bacillus Coagulans ◽  
Staph Aureus ◽  
Milk Samples ◽  
Sensitivity Tests ◽  
Bacillus Spp ◽  
Staphylococcus Spp

In this study 60 milk samples collected from mastitic cows to isolates and identify bacterial agents. The percentage of isolates was as follows: Staphylococcus spp 52%, Bacillus spp 26%, Enteroccocispp 3%; microccus 3%, Nesseria 2%, Branhamella 3%, Clostridium 1%, Bordetella 2%, Enterobacteria 3%, Aeromonas 4%, Fusobacterium 1%. In sensitivity tests used two antibiotics Amoxicillin and Cephalexin against two highest isolates in this study (Staph spp and Bacillus spp and found: Staph. aureus and Staph. hyicus were resistant to Amoxicllin and cephlaxin relatively, Bacillus coagulans and Bacillus cereus were susceptible to Amoxicllin and cephlaxin.

Ozone Concentration Prediction using Artificial Neural Networks

2017 ◽  
Vol 68 (10) ◽  
pp. 2224-2227 ◽  
Author(s):  
Camelia Gavrila
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Ozone Concentration ◽  
Meteorological Data ◽  
Global Solar Radiation ◽  
Time Data ◽  
Marquardt Algorithm ◽  
Sensitivity Tests ◽  
Artificial Neural ◽  
The Relationship

The aim of this paper is to determine a mathematical model which establishes the relationship between ozone levels together with other meteorological data and air quality. The model is valid for any season and for any area and is based on real-time data measured in Bucharest and its surroundings. This study is based on research using artificial neural networks to model nonlinear relationships between the concentration of immission of ozone and the meteorological factors: relative humidity (RH), global solar radiation (SR), air temperature (TEMP). The ozone concentration depends on following primary pollutants: nitrogen oxides (NO, NO2), carbon monoxide (CO). To achieve this, the Levenberg-Marquardt algorithm was implemented in Scilab, a numerical computation software. Performed sensitivity tests proved the robustness of the model and its applicability in predicting the ozone on short-term.

Operational Model and its Validation with Drift Tests in Water Areas Around the Baltic Sea

1994 ◽  
Vol 29 (2-3) ◽  
pp. 293-308
Author(s):  
J. Koponen ◽  
M. Virtanen ◽  
H. Vepsä ◽  
E. Alasaarela
Keyword(s):  
Three Dimensional ◽  
Fast Response ◽  
Velocity Measurements ◽  
Short Term ◽  
Large Lakes ◽  
Operational Model ◽  
Water Currents ◽  
Emergency Situations ◽  
Sensitivity Tests ◽  
The Baltic

Abstract Three-dimensional (3-D) mathematical models of water currents, transport, mixing, reaction kinetic, and interactions with bottom and air have been used in Finland regularly since 1982 and applied to about 40 cases in large lakes, inland seas and their coastal waters. In each case, model validity has been carefully tested with available flow velocity measurements, tracer studies and water quality observations. For operational use, i.e., for spill combatting and sea rescue, the models need fast response, proven validity and illustrative visualization. In 1987-90, validated models were implemented for operational use at five sea areas along the Finnish coast. Further validation was obtained in model applications from nine documented or arranged cases and from seven emergency situations. Sensitivity tests supplement short-term validation. In the Bothnian Sea, it was nescessary to start the calculation of water currents three days prior to the start of the experiment to reduce initial inaccuracies and to make the coastal transport estimates meaningful.

scholarly journals Testudines as Sentinels for Monitoring the Dissemination of Antibiotic Resistance in Marine Environments: An Integrative Review

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 775
Author(s):  
Kezia Drane ◽  
Roger Huerlimann ◽  
Michelle Power ◽  
Anna Whelan ◽  
Ellen Ariel ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Anthropogenic Activities ◽  
Sea Turtles ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Marine Environments ◽  
Beta Lactam ◽  
Antibiotic Resistant ◽  
Sensitivity Tests ◽  
Standard Culture

Dissemination of antibiotic resistance (AR) in marine environments is a global concern with a propensity to affect public health and many ecosystems worldwide. We evaluated the use of sea turtles as sentinel species for monitoring AR in marine environments. In this field, antibiotic-resistant bacteria have been commonly identified by using standard culture and sensitivity tests, leading to an overrepresentation of specific, culturable bacterial classes in the available literature. AR was detected against all major antibiotic classes, but the highest cumulative global frequency of resistance in all represented geographical sites was against the beta-lactam class by a two-fold difference compared to all other antibiotics. Wastewater facilities and turtle rehabilitation centres were associated with higher incidences of multidrug-resistant bacteria (MDRB) accounting for an average of 58% and 49% of resistant isolates, respectively. Furthermore, a relatively similar prevalence of MDRB was seen in all studied locations. These data suggest that anthropogenically driven selection pressures for the development of AR in sea turtles and marine environments are relatively similar worldwide. There is a need, however, to establish direct demonstrable associations between AR in sea turtles in their respective marine environments with wastewater facilities and other anthropogenic activities worldwide.

Sign in / Sign up

Export Citation Format

Share Document