MetEd: Meteorology Education and Training. Operated by the COMET Program

Description:
The Mesoscale Meteorology Primer is a Web-based distance learning curriculum designed to improve understanding and forecasting of mesoscale weather phenomena. The primer is collection of modules that use streaming audio, conceptual animations, and frequent interactions. The modules fall into two types: short conceptual Foundation Topics describing basic physical processes and forecasting tools, and longer modules that address specific mesoscale weather phenomena. These longer modules present a realistic forecast scenario, interactions, and a final exam.

Originally conceived by instructors in the U.S. Navy and Naval Postgraduate School (NPS), the participants also include meteorologists and multimedia developers from the COMET Program and the Air Force Weather Agency. Individual modules will take from 30 minutes to 2 hours to complete. When complete, the Mesoscale Meteorology Primer will contain approximately 26 modules.

Estimated time to complete: varies by choice of modules

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Description:
This self-paced course discusses the principles of major mountain weather concerns with the aim of improving the prediction of sensible weather in areas with complex terrain.

The course organizes relevant modules and Webcasts on the MetEd Website into three parts: Foundation Topics, Core Topics, and a Case Study. By using our Registration & Assessment system, you can track your progress in the course and receive a course completion certificate.

Estimated time to complete: 9-12 h

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Description:
This case study focuses on a snow and blowing snow event in the Canadian prairies and US northern high plains on 11-13 November 2003. The key aim of this module is to step through the forecast process during an Alberta Clipper event from the perspective of a forecaster with the Meteorological Service of Canada. This involves consideration of various observations and model guidance, identification of potential areas of snowfall and blowing snow, nowcasting snowfall development and termination, and considering and providing nowcast updates throughout.

Objectives:
* Recognize the key synoptic ingredients that can lead to the development of an Alberta Clipper.
* Determine the track of an Alberta Clipper
* Assess snowfall amounts associated with a clipper.
* Identify signals in the satellite and radar imagery as well as in the NWP data that can be associated with these systems.

Estimated time to complete: 1.50 - 2.00 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2010-01-05

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Description:
The goal of the EPV chart is to aid operational forecasters in predicting CSI and slantwise convection. The description includes links to the online chart, which is updated twice daily by the CMC, as well as a list of synoptic considerations that will support your use of the EPV chart in identifying regions favorable for CSI and slantwise convection.

Estimated time to complete: 20 min

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2002-01-05

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Description:
During this presentation, Dr. Brad Colman (NOAA/NWS) covers both the philosophical and methodological approaches to weather forecasting in general, with a special emphasis on challenges introduced in areas of complex terrain. The insightful comments made by the presenter regarding recommended approaches to applying conceptual models, mesoscale model output, and decision trees in the forecast process are useful to anyone who predicts the weather.

Objectives:
• Review the forecast process.
• Become aware of the challenges of forecasting in the diverse terrain of the Western U.S.
• Review the characteristics of mesoscale circulations.
• Describe the impact of complex terrain on simple geostrophic flow.
• Compare and contrast objective and subjective forecasting techniques.

Estimated time to complete: 35 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-12-22

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Description:
By the end of this module you will be able to answer...


* What is the mesoscale and how do we classify it?

* What is hydrostatic equilibrium?

* Why are non-hydrostatic processes so important to mesoscale meteorology?

* Why does forecasting mesoscale meteorology rely on model resolution?

* How might mesoscale processes impact fleet operations?

Objectives:
Terminal Objectives
By the end of this module you should be able to do the following:
1. Identify and classify mesoscale weather phenomena
2. Identify the NWP model characteristics required to forecast different mesoscale weather phenomena.

Enabling Objectives
By the end of this module you will be able to do the following:
1. Recall the horizontal and time scales of mesoscale-alpha, mesoscale-beta, and mesoscale-gamma weather phenomena.
2. Given a list of weather phenomena, correctly classify them as either mesoscale-alpha, mesoscale -beta, or mesoscale -gamma
3. Describe hydrostatic balance.
4. Recall why non-hydrostatic processes are so important to mesoscale meteorology?
5. Recall the relationship between mesoscale and synoptic scale NWP models.
6. Describe the relationship between grid spacing and model resolution for NWP models.
7. Correctly estimate the NWP model resolution required to accurately simulate several mesoscale weather phenomena, including topographically forced weather, development of fog and low stratus, and development of convective storms.

Estimated time to complete: 30 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2001-01-01

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Description:
Fog frequently forms in response to dynamically forced changes in the boundary layer. This module examines dynamically forced fog in the coastal and marine environment, focusing on advection fog, steam fog, and west coast type fog. The focus of the module is on the boundary layer evolution of air parcels as they traverse trajectories over land and water. The module also examines mesoscale effects that impact the distribution of fog and low-level stratus over short distances. A general discussion of forecast products and methodologies concludes the module.

Objectives:
After completing this module, the learner should be able to do the following things:

With regard to the general features of dynamically forced fog and stratus:

• Describe the differences in boundary layer characteristics and evolution for advection, West Coast, and steam fog in a marine environment
• Describe the differences in synoptic environments for advection, West Coast, and steam fog in a marine environment
• Describe the relationship of sea surface temperature to fog formation for advection, West Coast, and steam fog in a marine environment
With regard to advection fog:
• Describe the general synoptic environment that is conducive to fog formation
• List at least 2 ways that subtropical high-pressure systems contribute to the formation of advection fog
• Describe the evolution of the boundary layer along an air parcel trajectory that leads to advection fog
• Describe how sea surface temperature changes along an air parcel trajectory that leads to advection fog
• Recall the origins of strong sea surface temperature gradients
• On a world map, identify areas prone to advection fog
• Recall the seasonality of advection fog

With regard to West Coast fog and low stratus:

• Describe the general synoptic environment that is conducive to fog formation
• List at least 2 ways that subtropical high-pressure systems contribute to the formation of West Coast fog and low stratus
• Describe the evolution of the boundary layer along an air parcel trajectory that leads to West Coast fog and low stratus
• List at least 2 ways that the boundary layer cools to saturation in a West Coast fog/stratus event.
• Recall the role of upwelling in the formation of West Coast fog and low stratus
• On a world map, identify areas prone to West Coast fog and low stratus
• Recall the seasonality of West Coast fog and low stratus
With regard to steam fog:
• Describe the general synoptic environment that is conducive to fog formation
• Describe the characteristics and evolution of the boundary layer along an air parcel trajectory that leads to steam fog
• On a world map, identify areas prone to steam fog
• Recall the seasonality of steam fog events

With regard to mesoscale influences upon dynamically forced fog:

• Describe the effects of coastal topography in fog formation
• Describe how coastal jets affect fog formation and dissipation
• Describe how sea breezes affect fog formation and dissipation
• Describe the impact of local variations in sea surface temperature on fog formation and dissipation

With regard to forecasting dynamically forced fog:

• Describe the general approach to forecasting fog
• List at least 4 critical atmospheric fields to monitor in plan view when forecasting fog
• List at least 4 critical atmospheric fields to monitor in vertical profiles when forecasting fog
• Describe the limitations of NWP models in fog forecasting

Estimated time to complete: 3 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2005-03-01

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Description:
In this Webcast, Dr. James Steenburgh, working for the Department of Meteorology and the NOAA Cooperative Institute for Regional Prediction at the University of Utah, takes a look at cool-season orographic storms in western North America. He provides a brief microphysics review, an overview of cool-season orographic precipitation processes in several mountain ranges, and a look at forecasting tools and techniques. This Webcast is based on a classroom presentation given in Boulder, CO in December 2002.

Objectives:
• Improve knowledge of orographic precipitation processes and their geographical, climatological, and storm-to-storm variability.
• Build or enhance your orographic precipitation forecasting tool chest.
• Illustrate the strengths and weaknesses of quantitative precipitation forecasts by high-resolutions models in complex terrain.

Estimated time to complete: 1 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2004-08-09

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Description:
This module consists of four exercises where users identify surface features, distinguish clouds from snow on the ground, and determine cloud phase using multispectral analysis. The module also includes an overview of multispectral techniques available on many operational and research polar-orbiting satellites. A page with links to real-time polar-orbiting data and information is also included.

Objectives:
• State the properties of the 1.6 micrometer channel used in feature identification
• State the properties channels in the 3.5 to 4 micrometer region in feature identification
• List the advantages and limitations of the 1.6 micrometer channel in cloud identification
• List the advantages and limitations of the 1.6 micrometer channel in identifying snow on the ground
• List the advantages and limitations of channels in the 3.5 to 4 micrometer region for cloud identification
• List the advantages and limitations of channels in the 3.5 to 4 micrometer region in identifying snow on the ground
• Apply the properties of the visible, IR Window, 1.6 micrometer, and 3.7 micrometer channels to:
o Distinguish clouds from snow on the ground
o Determine the phase (ice or water) of clouds
o Detect the presence of fog
o Distinguish open water from ice-covered areas of lakes and rivers

Estimated time to complete: 1-2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2002-07-03

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Description:
Forecasting Dust Storms is the latest module in the Mesoscale Meteorology Primer. The module starts by discussing the conditions required for a dust storm, including an appropriate source of dust, sufficient wind and turbulence, and an unstable atmosphere. The module then explores the fate of dust in the atmosphere including dispersion, advection, and settling. The concluding section on forecasting examines a case in the Middle East and demonstrates the use of a mesoscale NWP model, as well as next-generation dust forecasting models.

Objectives:
After completing this module, the learner should be able to do the following things:

With regard to dust storm characteristics:

• Describe how visibility varies near severe dust storms
• Recall the average height of dust storms
With regard to sources of dust:
• Describe the soil types in appropriate source regions for dust storms
• Recall that blowing dust usually does not occur for at least 24 hours after a rainfall
• Identify potential source regions with satellite imagery

With regard to atmospheric conditions required for dust storms:

• Recall the threshold wind speed for lifting fine dust particles.
• Describe the atmospheric conditions that promote lofting of dust in terms of stability and turbulence
• List the 3 ways that turbulence typically arises in the atmosphere
• Describe the effect of nightfall on dust storms

With regard to the dissipation and dispersion of dust storms:

• Describe the atmospheric factors that influence the dispersion of dust
• Describe the effect of precipitation on suspended dust and why this occurs
• Recall how quickly dust settles once winds die down

With regard to the climatology of dust storms:

• List the most common synoptic patterns for raising dust in the Middle East
• Define Shamal
• List at least 3 mesoscale weather phenomena that result in dust storms
• Describe how haboobs and dust devils originate
• Describe how winter dust storms differ from summer dust storms

With regard to the satellite detection of blowing dust:

• Describe how dust appears on IR images, during both day and night and over both land and water
• Describe how dust appears on visible images, during both day and night and over both land and water
• Describe the advantages of imagery from polar orbiting and geostationary satellites
• With regard to forecasting dust storms:
• List the tools available for observing dust storms.
• Describe how mesoscale NWP models can help with a dust storm prediciton
• List the dust storm forecasting models and describe their respective advantages

Estimated time to complete: 2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-10-23

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Description:
“Frontogenetical Circulations and Stability” is a Webcast by Dr. James T. Moore that focuses on an overview of different stability types, including convective, potential, inertial, conditional and symmetric, the concept of frontogenesis and associated circulations. The webcast concludes with a discussion of the role of stability in determining the character of frontogenetical circulations.

Objectives:
1. Understand various types of stability, including convective, potential, inertial, conditional and symmetric, and recognize when they might occur for a given forecast situation.

2. Understand the concept of frontogenesis/frontolysis and associated circulations that result.

3. Recognize the impact of stability on the character of frontal circulations.

Estimated time to complete: 45 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2007-10-24

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Description:
The goal of this training module is to help you increase your understanding of how mesoscale models work. Such understanding, in turn, can help you more efficiently and accurately evaluate model-generated forecast products.

Objectives:
Terminal Objectives
By the end of this module you will be able to do the following:
1. Describe how mesoscale models work
2. Evaluate the strengths and weaknesses of different NWP models

Enabling Objectives
By the end of this module you will be able to do the following:
1. Describe the benefits and limitations of mesoscale NWP models.
2. Describe the relationship between grid spacing and model resolution for NWP models.
3. Describe the pros and cons of increasing model resolution
4. Describe hydrostatic balance and how hydrostatic NWP models differ from non-hydrostatic NWP models
5. Define Eta, sigma, and pressure vertical coordinates schemes and describe their respective advantages.
6. Define parameterization and describe the benefits of its use in NWP models
7. List at least 3 processes that are typically parameterized.
8. Describe limited area model (LAM), spin-up, and warm start, and how they are all related.
9. Describe the benefits and limitations of a warm start.

Estimated time to complete: 30 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2002-04-22

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Description:
This Webcast is based on a presentation given by Dr. James T. Moore of Saint Louis University at the 5th Annual MSC/COMET Winter Weather Workshop on 30 November 2004 in Boulder, Colorado. Dr. Moore reviews many aspects of jet streak dynamics including convergence/divergence, ageostrophic winds, propagation, and coupled jets.

Objectives:
• Define "jetstreak"
• Note the divergence associated with upper-level waves
• Describe the relationship of divergence with vertical windshear
• Describe the relationship of the ageostrophic wind components with upper-level and low-level jets
• Compare the direct thermal circulation in the entrance region with the indirect thermal circulation in the exit region of an upper-level jet
• Identify how the curvature of an upper-level jet affects divergence and convergence
• Describe the impact thermal advection has on vertical motion and entrance and exit circulations
• Gain an understanding of the characteristics of unbalanced jets and coupled jets

Estimated time to complete: 50 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2005-04-25

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Description:
Landfalling cyclones and their attendant fronts significantly impact the structure of mesoscale wind and precipitation fields along the west coast of North America. This module focuses on the complex interaction of the wind field with topography and the resulting effects on nearshore winds and precipitation. For example, prefrontal conditions may lead to flow blocking, development of a barrier jet, and seaward displacement of the maximum precipitation. Postfrontal conditions tend to promote windward ridging and lee troughing, which enhance along-coast flow.

Objectives:

Performance Objectives

After completing the module, the learner should be able to do the following tasks:

• Describe the conditions under which flow becomes blocked by topography.


• Given the wind speed, stability (Brunt-Vaisala Frequency), and mountain height, determine whether flow will be blocked by topography.


• Describe how the angle between a landfalling front and the coastline
  affects the flow/topography interaction.


• Describe how the prefrontal environment may experience enhanced stability.


• Describe the conditions that lead to formation of a barrier jet.


• Describe the change in the pressure field as cold fronts make landfall.


• Given a landfalling front under conditions conducive to flow blocking,
  describe the anticipated effects on the motion of the cold front, the
  wind field, and the precipitation field.


• Given a landfalling front under conditions that are not conducive
  to flow blocking, describe the anticipated effects on the motion of
  the cold front, the wind field, and the precipitation field.


• Describe the advantages in using a high-resolution model to forecast the
  effects of landfalling fronts, compared to lower-resolution models.

Estimated time to complete: 1.5 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2006-05-24

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Description:
This website provides access to the streaming presentations and PowerPoint source files for the 11 lectures delivered during the AMS Educational Forum “A Primer on Radar Analysis Techniques Used in Mesoscale Meteorology” held on 23 October 2005 in Albuquerque, NM. The presentations discuss how many advanced techniques for the analysis of meteorological radar data can be used to improve understanding of the structure, dynamics, and evolution of mesoscale circulations. The Forum was organized into four sections: 1) Microphysical Characterization of Precipitation Systems Using Dual-Polarization Radar Measurements, 2) Single Doppler Retrieval and Assimilation Techniques for Use in Mesoscale Models, 3) Analysis of Mesoscale Processes Using Wind Profiling Radars and Velocity Azimuth Display and 4) Airborne Doppler Radar Analysis of Tropical and Extratropical Mesoscale Systems.

Objectives:
The objective of the Forum was primarily to introduce graduate students to important radar analysis techniques as they are used in atmospheric science research with the goal of improving our understanding of the structure, dynamics, and evolution of mesoscale circulations. A basic, formal understanding of both radar and mesoscale meteorology is necessary to gain the most from the lectures. Each individual presentation is rated as either intermediate or advanced level content.

Estimated time to complete: 8 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2006-02-07

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Description:
The Mesoscale Aspects of Winter Weather Forecasting effort is comprised of a growing series of in-depth case exercises bundled with supporting topics. This site provides access to the supporting topics seperate from the case exercises.

Estimated time to complete:

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-10-12

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Description:
Precipitation frequently falls and accumulates in discrete bands with accumulations that vary markedly over short distances. This module examines several mechanisms that result in mesoscale banded precipitation, focusing primarily on processes at work in midlatitude cyclones. The module starts with a review of the Norwegian and conveyor belt cyclone models. Then several banding processes are examined in detail, including deformation/frontogenesis, the Trowal (Trough of Warm Air Aloft), frontal merger, CSI/slantwise convection, and melting/evaporation-induced circulations. The module concludes with discussions of the representation of banded precipitation by NWP models and the detection of banded precipitation with satellite sensors.

Objectives:
After completing this module, the learner should be able to do the following things.


With regard to the general features of mesoscale banded precipitation:

* Recall the operational definition of a precipitation band

* Describe the relationship between instantaneous and accumulated bands of precipitation

* Recall the basic requirements for precipitation and the role of atmospheric stability


With regard to the association between midlatitude cyclones and mesoscale banded precipitation:

* Recall and describe the different types of fronts in the Norwegian cyclone model

* Describe the typical precipitation field associated with each kind of front

* Distinguish an anafront from a katafront in forecast products

* Distinguish a cold occluded front from a warm occluded front in forecast products

* Recall and describe the types of air streams in the conveyor belt model of midlatitude cyclones

* Describe the relationship between air streams and fronts

* Describe the relationship between air streams and mesoscale banded precipitation

* Recognize different air streams in satellite images and forecast products

* Recall what a trowal is and where it occurs

* Describe the relationship between the trowal and banded precipitation

* Describe the trowal signature in forecast products

* Locate a trowal on satellite images and forecast products


With regard to processes that lead to mesoscale banded precipitation.

* Define the terms: deformation, frontogenesis, frontolysis

* Describe how deformation leads to frontogenensis

* Describe the vertical motions associated frontogenesis

* Describe how frontogenesis leads banded precipitation

* Recognize and diagnose deformation and frontogenesis in forecast products

* Describe circulations induced by melting and evaporation in the lower tropsphere

* Describe the relationship between melt/evaporation-induced circulations, frontogenesis, and banded precip

* Recognize and diagnose banded precipitation forced by melt/evaporation-induced circulations in forecast products

* Define frontal merger

* Describe the difference between frontal merger and frontal occlusion

* Describe a typical synoptic setting for frontal merger and its relationship with midlatitude cyclones

* Describe the relationship between frontal merger and banded precipitation

* Recognize and diagnose frontal merger in forecast products

* Describe the relationship between CSI and slantwise convection

* Describe the atmospheric conditions conducive to CSI

* Describe what atmospheric conditions lead to low inertial stability

* Recognize and diagnose CSI and slantwise convection with cross-sectional analysis.


With regard to the simulation of mesoscale banded precipitation by NWP models:

* Given the grid spacing determine the grid resolution

* Describe the characteristics of a hydrostatic atmosphere

* State why high-resolution NWP models need to be non-hydrostatic

* Describe the need for parameterization in NWP models

* Describe the pros and cons of parameterization versus explicit treatment of processes

* Describe the difference between prognostic and diagnostic moisture physics and the benefits of each

* Characterize COAMPS and NOGAPS


With regard to the detection of mesoscale banded precipitation by satellite sensors:

* Describe the benefits and drawbacks of satellite estimates of precipitation

* Recall at least 4 satellite sensors that measure precipitation

* Describe the benefits and drawbacks of the GOES Precipitation Index

* Describe the benefits and drawbacks of precipitation estimates derived from microwave sensors

* Describe how a blended precipitation product is derived

Estimated time to complete: 3 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2005-06-24

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Description:
This module presents current conceptual models of several MCS types and provides explanations for the structures and behavior of MCSs based on the physical processes underlying their evolution. An understanding of the physical processes and conceptual models of MCSs will help forecasters to predict the most likely locations of severe weather within existing systems and to forecast the longevity, areal extent, and path of the system.

Accompanied by conceptual animations, numerical simulations, and case studies, Mesoscale Convective Systems: Squall Lines and Bow Echoes presents strategies with which the forecaster can identify the potential for long-lived MCSs and attendant severe weather.

Estimated time to complete: 4-6 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 1999-05-28

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Description:
The Primer of Mesoscale Meteorology is a web-based training program designed to improve forecasting of mesoscale weather. The primer is collection of web-based modules that use advanced multimedia features now available over the web, including streaming audio, conceptual animations, and frequent interactions. The courses, or modules, that comprise the primer fall into two types: short conceptual foundation modules and longer, more elaborate modules that address specific mesoscale weather phenomena. The conceptual foundation modules are linked to as appropriate to provide a level of elaboration that might otherwise disrupt the flow of the larger module.

Estimated time to complete:

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2002-01-01

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Description:
The Workshop on the Weather Research and Forecast model and the North American Ensemble Forecast System was given at the regional training center in Pretoria, South Africa in October, 2007, sponsored by NOAA NWS, coordinated by Wassila Thiaw (African Training Desk Coordinator, NCEP), and organized with the assistance of the WMO and South Africa Weather Service (SAWS). The goal of the workshop was to support capacity building efforts on the use of numerical weather prediction (NWP) products in Africa. This Webcast collection offers seven lectures from the workshop, including Introduction to Mesoscale Models (WRF), Introduction to Local Area Modeling (WRF), Statistical Methods in Ensemble Prediction (GEFS/NAEFS, Case Study Model Performance (GEFS/NAEFS), Model Jumpiness (GEFS/NAEFS), Operational Use of Bias-Corrected Products (GEFS/NAEFS), and Africa Case Example (GEFS/NAEFS), presented by lecturers Mr. Eric Altshuler (Institute of Global Environment and Center for Ocean-Land-Atmosphere Studies), Dr. William Bua (UCAR/COMET), and Mr. Richard Grumm (NOAA/NWS).

Objectives:
These lectures are intended for professional meteorologists aspiring to become NWP specialists and for operational weather forecasters who seek to gain understanding and proficiency in the use of ensemble prediction systems (EPS) in operational weather forecasting.

The extensive list of learning objectives included in these material:
For concepts related to NWP model forecast uncertainty and ensemble prediction systems:
• Anticipate the impact of changing initial conditions between forecast cycles.
• State how lagged average forecasts are constructed.
• On a given model product, identify areas where forecast uncertainty is likely highest.
• State how bias correction is performed and its impact on forecast skill.
• Describe the benefits of an ensemble forecast system.
• Describe general qualities of the GFS data assimilation system.

For statistical methods used in producing ensemble prediction system output:
• Define median, mean, mode, standard deviation, quartiles, and deciles .
• Describe the effect of the mean bias.
• Identify indicators of sharpness in forecast distributions.
• Use a contingency table to determine probability of occurrence.
• Distinguish between “reliability” and “resolution.”

For effective use of the WRF local area model:
• State the utility of convective parameterization.
• Define “mesoscale.”
• State what is represented by a grid point forecast.
• State where high vertical resolution is most critical.
• Describe the relative impact of higher horizontal resolution on mesoscale circulations like a sea breeze.
• Describe the relationship between time steps and wave propagation in regard to forecast accuracy.
• Describe how horizontal resolution impacts the ability to use non-hydrostatic dynamics.
• State processes and quantities resolved by microphysics schemes.
• State the reasons for using upper boundary conditions in limited area models.
• Describe benefits of local area models.
• List acceptable data for defining lateral boundary conditions in the WRF.
• Describe how lateral boundary conditions can degrade a WRF EMS forecast.
• Describe the impacts of increasing resolution in regions of strong topography on precipitation forecasts.
• Evaluate the relative impact on forecast accuracy introduced by (a) decreasing time steps, (b) increasing temporal resolution of boundary conditions, (c) increasing spatial resolution of initial conditions, (d) increasing vertical resolution, and (e) increasing spatial resolution of boundary conditions.

Estimated time to complete: 9 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2008-10-13

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Description:
The NCEP Real-Time Mesoscale Analysis (RTMA), provides current conditions in digital form on the NWS National Digital Forecast Database (NDFD) 5-km grid. This product was upgraded in early July 2007 to the point where its use by forecast offices is now encouraged for situational awareness, creating short-term forecast grids, and evaluating recent forecast grids and forecast bias. Unique to the RTMA is an uncertainty or error estimate for some of its analysis parameters. These uncertainty estimates perhaps could be used to determine when a forecast is “good enough”. This Webcast discusses why the RTMA and its parent project, the Analysis of Record, were created, how the RTMA is generated, and its capabilities, limitations, and possible applications. The Webcast includes extensive discussion about how representative individual observations are and how they are handled by the analysis. The topics covered include:

* The context for developing the RTMA and related future developments
* Use of the RTMA in the human forecast process
* The steps in generating RTMA products: forecast, downscaling, observation data sets, quality control, two-dimensional variational analysis (2d-var), “uncertainty” estimates, multisensor precipitation analysis, and GOES Effective Cloud Amount
* Limitations related to how RTMA products are generated
* How an observation affects the 2d-var analysis
* Issues raised by the analysis using accurate observations which are not representative of their surrounding area
* Preliminary performance assessment over complex terrain
* Key changes under development for future RTMA implementations

Objectives:

1. Big picture - Understand why RTMA was created and how it fits into the Analysis of Record project
   
2. Be able to apply RTMA in your forecast operations
   1. Be aware of which data types are used/not-used
      
   2. Recognize that a perfect analysis should not exactly fit observations
      
   3. Be familiar with what products exist
      
   4. Be familiar with how the products are made and therefore understand their capabilities and limitations
3. Be aware of how future changes already under development will affect the RTMA product suite
   

Estimated time to complete: 1 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2007-08-14

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Description:
Meteorologists typically examine atmospheric soundings in the course of preparing a weather forecast. The skew-T / log-P diagram provides the preferred method for analyzing these soundings. This module comprehensively examines the use of the skew-T diagram. It explores thermodynamic properties, convective parameters, stability assessment, and several forecast applications. The module is designed for both instruction and reference. It also comes with an interactive Web-based skew-T diagram that calculates several common forecast parameters.

Objectives:
Module Goal
The goal of this module is to teach the novice forecaster to effectively use the skew-T/log-P diagram. After completing the module, they should be able to read and interpret a sounding plotted on a skew-T/log P diagram and apply that information to a weather forecast.

Performance Objectives

1. Given a skew-T/log-P diagram, identify and describe the various lines.


2. Given a sounding plotted on a skew-T/log-P diagram:




• Read or calculate the thermodynamic properties at various levels.


• Determine the convective levels, including the LCL, CCL, LFC, MCL, EL, and MPL.


• Determine stability indices such as LI, SSI, KI, TT, and SWEAT and use them to assess the potential for severe weather.




3. Describe how CAPE and CIN are determined.


4. List and describe the different types of stability and identify them in a sounding plotted on a skew-T diagram


5. List and describe the different types of lapse rates and relate them to stability.


6. List and describe processes that alter stability and give examples of common cases where those processes occur.


7. Given a suitable synoptic environment and a sounding plotted on a skew-T/log-P diagram, interpret the sounding with regard to common forecast problems.

Estimated time to complete: 6-8 h

Includes audio: no

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Last published on: 2006-10-04

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Description:
This exercise examines an event that took place in the 24 hour time period beginning at 18Z, Dec 31, 2000 in southern British Columbia, Canada and northern Washington/Idaho, United States. This is a companion piece to the COMET Webcast, Slantwise Convection: An Operational Approach.

Objectives:
• Apply techniques for assessing and forecasting conditional symmetric instability and associated slantwise convection

Estimated time to complete: 45 min

Includes audio: no

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Last published on: 2002-06-17

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Description:
This Webcast is a recreation of a presentation on slantwise convection given by Kent Johnson in February, 2002 in Boulder, Colorado. It focuses on assessing the release of conditional symmetric instability as slantwise convection. It provides an overview of the characteristics and theory of CSI, assessment of CSI and slantwise induced precipitation in complex terrain, and operational challenges to assessing CSI.

Objectives:
1. Show that the atmosphere can be intertially and gravitationally stable, but unstable to a slantwise displacement when near or at saturation.

2. Demonstrate the vertical-cross section approach in diagnosing the potential for conditional symmetric instability (CSI).

3. Examine ways to improve forecasts that involve a potential slantwise convection situation.

4. Examine the typical characteristics of CSI in complex terrain.

5. Apply a slantwise convection analysis to a real world situation.

Estimated time to complete: 40 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
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Last published on: 2002-06-17

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Description:
This 7-page module provides a primer on geostrophic adjustment concepts. It discusses their application for understanding and forecasting real weather features, interpreting model forecasts, and recognizing the type and duration of impact that observations exert on the model forecast. The module also includes an interactive Exercises section.

Estimated time to complete: 1 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
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Last published on: 2002-11-25

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Description:
This Webcast introduces the SPoRT Center, a joint NASA and National Weather Service project to provide unique NASA datasets to several forecast offices and evaluate their usefulness and impact on forecast operations. The presentation provides a description of the SPoRT Center, examples of its collaborations with weather forecast offices, and demonstrates use of MODIS data, AMSR-E derived products and lightning flash density product applications. It also includes mention of the projects the SPoRT Center will likely undertake in the future. The information contained in this Webcast reflects the status of the SPoRT program as of the summer of 2006. Since the SPoRT program evolves to meet NASA program objectives, some of the capabilities or activities portrayed in this presentation may have changed since its original production.

Objectives:
After completing the Webcast the learner will be able to:

• Describe the SPoRT program
  
• State the mission of the SPoRT program
  
• State advantages of using MODIS true-color imagery
  
• Explain how higher resolution MODIS data can complement GOES and insitu data
  
• State the advantages of AMSR-E data for coastal forecasters.
  
• State an advantage of using MODIS SST data for model initialization
  
• State how the SPoRT program works with local, regional, and national levels of the NWS
  
• Describe North Alabama Lightning Array data sets and their contribution to forecasting convection
  

  Estimated time to complete: 1 h

  Includes audio: yes

  Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
   * Plug-in information

  Last published on: 2007-02-28

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Description:
In this Webcast, Dr. Schultz outlines the subtle and often confusing issues surrounding conditional symmetric instability. Material is then presented to encourage the meteorological community to properly apply these concepts to diagnose actual regions of CSI and apply that knowledge to forecasting banded precipitation. Avenues for future research are also discussed.

This lesson is based on an article of the same name that appears in the Dec.1999 issue of the AMS journal, Monthly Weather Review. In response to feedback, a version of this Webcast that can be installed on your computer for local playback is also provided.

Objectives:
1. Point out pitfalls so that they don't continue to be perpetuated

2. Illustrate some deficiencies in our understanding of CSI

3. Recommend operational uses of CSI that are consistent with our current state of knowledge

4. Encourage future operational research explorations

Estimated time to complete: 30 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
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Last published on: 2000-01-07

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Description:
Les cartes de TPE, produites au CMC deux fois par jour, sont disponibles au Web à l’adresse fournie dans ce document. Il s’y trouve aussi une liste de facteurs synoptiques destiné aux météorologues d’exploitation pour encadrer leur utilisation des cartes de TPE dans l’identification et la prévision des régions de l’ICS et de la convection penchée.

Estimated time to complete: 20 min

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
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Last published on: 2002-01-05

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Description:
El objetivo de este módulo de capacitación es ayudarle a aumentar su grado de comprensión del funcionamiento de los modelos de mesoescala. A su vez, dicha comprensión puede ayudarle a evaluar de forma más eficiente y precisa los productos de pronóstico generados por los modelos numéricos.

Objectives:
Objetivos finales
Cuando termine de estudiar este módulo podrá:
1. Describir cómo funcionan los modelos de mesoescala.
2. Evaluar los puntos fuertes y débiles de los diferentes modelos de PNT.

Objetivos de capacitación
Cuando termine de estudiar este módulo podrá:
1. Describir las ventajas y limitaciones de los modelos de PNT de mesoescala.
2. Describir la relación entre el espaciado de malla y la resolución para los modelos de PNT.
3. Describir las ventajas y desventajas de aumentar la resolución del modelo.
4. Describir el equilibrio hidrostático y cómo los modelos de PNT hidrostáticos difieren de los no hidrostáticos.
5. Definir los esquemas de coordenadas verticales Eta, sigma y de presión, y describir sus respectivas ventajas.
6. Definir la parametrización y describir los beneficios de su uso en los modelos de PNT.
7. Enumerar al menos tres procesos que suelen parametrizarse.
8. Describir los conceptos de modelo de área limitada, fase de inicialización y arranque en caliente, así como la relación que existe entre ellos.
9. Describir los beneficios y las limitaciones del arranque en caliente.

Estimated time to complete: 30 min

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
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Last published on: 2007-05-21

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Description:
A menudo, la precipitación cae y se acumula en bandas discretas, con cantidades que varían considerablemente sobre distancias cortas. Este módulo examina varios mecanismos que producen precipitación en bandas de mesoescala, centrándose principalmente en los procesos que operan en los ciclones de latitudes medias. El módulo comienza con una descripción de los modelos de ciclogénesis noruego y de cinta transportadora. A continuación se examinan en detalle varios procesos de precipitación en bandas, incluidas la deformación/frontogénesis, las lenguas de aire cálido en altura (Trowal, o TROugh of Warm air ALoft), la unión de frentes, la inestabilidad condicional simétrica/convección oblicua y las circulaciones inducidas por fusión/evaporación. El módulo concluye con algunas discusiones sobre la representación de la precipitación en bandas por los modelos de PNT y la detección de la precipitación en bandas mediante sensores satelitales.

Estimated time to complete: 3 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
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Last published on: 2007-09-28

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Description:
Es normal examinar los sondeos atmosféricos como parte del proceso de preparación del pronóstico del tiempo. El diagrama oblicuo T-log p es uno de los métodos más difundidos de analizar estos sondeos. Este módulo examina a fondo el uso del diagrama oblicuo T-log p, y explora las propiedades termodinámicas, los parámetros convectivos, la evaluación de la estabilidad y varias aplicaciones de pronóstico. El módulo ha sido diseñado para instrucción y referencia. También incluye un diagrama oblicuo T-log p interactivo basado en web que calcula varios parámetros de predicción comunes.

Objectives:


Objetivo del módulo
El objetivo de este módulo es enseñar al meteorólogo principiante a utilizar el diagrama oblicuo T - log p de forma eficaz. Después de completar el módulo, usted debería ser capaz de leer e interpretar la representación de un sondeo en un diagrama oblicuo T - log p y aplicar la información al realizar un pronóstico del tiempo.

Objetivos prácticos

1. Dado un diagrama oblicuo T - log p, identificar y describir sus diferentes líneas.


2. Dada la representación de un sondeo en un diagrama oblicuo T - log p:


• leer o calcular las propiedades termodinámicas en diferentes niveles;


• determinar los niveles convectivos, incluidos NCA, NCC, NCL, NCM, NE y NMP;


• determinar los índices de estabilidad, como LI, SSI, KI, TT and SWEAT, y utilizarlos para calcular el potencial de tiempo severo;


3. Describir cómo se determinan la CAPE y CIN.


4. Enumerar y describir los diferentes tipos de estabilidad e identificarlos en un sondero representado en un diagrama oblicuo T - log p


5. Enumerar y describir los diferentes tipos de gradientes térmicos y relacionarlos con la estabilidad.


6. Enumerar y describir los procesos que alteran la estabilidad y dar ejemplos de casos comunes donde ocurren.


7. Dado un ambiente sinóptico apropiado y un sondeo en un diagrama oblicuo T - log p, interpretar el sondeo teniendo en cuenta los problemas de pronóstico más comunes.

Estimated time to complete: 6-8 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2008-08-21

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Description:
La niebla se levanta con frecuencia en respuesta a cambios forzados dinámicamente en la capa límite planetaria. Este módulo examina la niebla provocada por forzamiento dinámico en los entornos costero y marino, con énfasis en la niebla de advección, la niebla de vapor y las nieblas típicas de la costa del Pacífico de EE.UU. El módulo estudia a fondo la evolución de las parcelas de aire en la capa límite a medida que atraviesan trayectorias sobre tierra y agua. El módulo examina también los efectos de mesoescala que influyen en la distribución de niebla y estratos en los niveles inferiores sobre distancias cortas. El módulo concluye con una discusión general de los productos y las metodologías de pronóstico.

Objectives:
Cuando termine de estudiar este módulo, podrá:

En lo referente a las características generales de la niebla y nubes estratos por forzamiento dinámico:
• describir las diferencias en las características y la evolución de la capa límite para la niebla de advección, la niebla en la costa occidental de los continentes y la niebla de vapor en un entorno marino;
• describir las diferencias en el entorno sinóptico para la niebla de advección, la niebla en la costa occidental de los continentes y la niebla de vapor en un entorno marino;
• describir la relación entre la temperatura de la superficie del mar y la formación de niebla de advección, niebla en la costa occidental de los continentes y niebla de vapor en un entorno marino.

En lo referente a la niebla de advección:
• describir el entorno sinóptico general propicio para la formación de la niebla;
• enumerar al menos dos maneras en que los sistemas subtropicales de alta presión contribuyen a la formación de niebla de advección;
• describir la evolución de la capa límite a lo largo de la trayectoria de una parcela que lleva a la formación de niebla de advección;
• describir los cambios en la temperatura de la superficie del mar a lo largo de la trayectoria de una parcela que lleva a la formación de niebla de advección;
• explicar los orígenes de los gradientes fuertes de temperatura de la superficie del mar;
• identificar en un mapa mundial las áreas propicias para los eventos de niebla de advección;
• explicar la estacionalidad de los eventos de niebla de advección.

En lo referente a la niebla y nubes estratos bajas en la costa occidental de los continentes:
• describir el entorno sinóptico general propicio para la formación de la niebla;
• enumerar al menos dos maneras en que los sistemas subtropicales de alta presión contribuyen a la formación de niebla y estratos bajos en la costa occidental de los continentes;
• describir las características y la evolución de la capa límite a lo largo de la trayectoria de una parcela que lleva a la formación de niebla y estratos bajos en la costa occidental de los continentes;
• enumerar al menos dos maneras en que la capa límite se enfría hasta el punto de saturación durante un evento de niebla y estratos en la costa occidental de los continentes;
• describir el papel del afloramiento en la formación de niebla y estratos bajos en la costa occidental de los continentes;
• identificar en un mapa mundial las áreas propicias para los eventos de niebla y estratos en la costa occidental de los continentes;
• explicar la estacionalidad de los eventos de niebla y estratos bajos en la costa occidental de los continentes.

En lo referente a la niebla de vapor:
• describir el entorno sinóptico general propicio para la formación de la niebla;
• describir las características y la evolución de la capa límite a lo largo de la trayectoria de una parcela que lleva a la formación de niebla de vapor;
• identificar en un mapa mundial las áreas propicias para los evento de niebla de vapor;
• explicar la estacionalidad de los eventos de niebla de vapor.

En lo referente a los efectos de mesoescala en la niebla por forzamiento dinámico:
• describir los efectos de la topografía costera en la formación de la niebla;
• describir cómo los chorros costeros afectan la formación y disipación de niebla;
• describir cómo las brisas marinas afectan la formación y disipación de niebla;
• describir el impacto de las variaciones locales en la temperatura de la superficie del mar sobre la formación y disipación de niebla.

En lo referente al pronóstico de niebla por forzamiento dinámico:
• describir el enfoque general de pronóstico de niebla;
• enumerar al menos cuatro campos atmosféricos esenciales que es preciso vigilar en el plano horizontal al pronosticar la niebla;
• enumerar al menos cuatro campos atmosféricos esenciales que es preciso vigilar en los perfiles verticales al pronosticar la niebla;
• describir las limitaciones de los modelos numéricos para pronosticar la niebla.

Estimated time to complete: 3 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2009-05-05

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Description:
Éste es el módulo más reciente del Manual de meteorología de mesoescala (Mesoscale Meteorology Primer). El módulo comienza con una discusión de las condiciones necesarias para la formación de las tormentas de polvo, como una fuente adecuada de polvo, vientos y turbulencia suficientes y una atmósfera inestable. A continuación el módulo explora lo que ocurre con el polvo en la atmósfera, incluidos los aspectos de dispersión, advección y deposición. La sección final sobre pronósticos examina un caso ocurrido en el Medio Oriente y demuestra el uso de un modelo de PNT de mesoescala, así como modelos de pronóstico de tormentas de polvo de próxima generación.

Objectives:
Objetivos del módulo

Cuando termine de estudiar este módulo, podrá:

En lo referente a las características de las tormentas de polvo:
• describir cómo la visibilidad varía cerca de una tormenta de polvo severa;
• recordar la altura media que alcanzan las tormentas de polvo.

En lo referente al origen del polvo:
• describir los tipos de suelo que se hallan en las regiones de origen de tormentas de polvo;
• recordar que normalmente no se levanta una nube de polvo durante al menos 24 horas después de un episodio de lluvia;
• identificar las potenciales regiones de origen en imágenes satelitales.

En lo referente a las condiciones atmosféricas necesarias para levantar una tormenta de polvo:
• recordar el umbral de velocidad del viento necesario para levantar las partículas de polvo finas;
• describir las condiciones atmosféricas propicias para levantar el polvo en términos de estabilidad y turbulencia;
• enumerar las tres formas en que la turbulencia suele surgir en la atmósfera;
• describir el efecto del anochecer en las tormentas de polvo;

En lo referente a la disipación y dispersión de tormentas de polvo:
• describir los factores atmosféricos que afectan la dispersión del polvo;
• describir el efecto de la precipitación en el polvo suspendido en el aire y por qué esto ocurre;
• recordar con qué velocidad se deposita el polvo una vez que los vientos se calman.

En lo referente la climatología de las tormentas de polvo:
• enumerar los patrones sinópticos más comunes que levantan el polvo en el Medio Oriente;
• dar una definición del chamal;
• enumerar al menos tres fenómenos de mesoescala que provocan tormentas de polvo;
• describir el mecanismo que produce las tempestades de polvo (habub) y las tolvaneras;
• describir la diferencia entre una tormenta de polvo de invierno y de verano.

En lo referente a la detección satelital de las nubes de polvo:
• describir el aspecto del polvo en las imágenes infrarrojas, tanto de día como de noche y sobre agua y tierra firme;
• describir el aspecto del polvo en las imágenes en el visible, tanto de día como de noche y sobre agua y tierra firme
• describir las ventajas de las imágenes de los satélites en órbita polar y geoestacionarios;

En lo referente al pronóstico de tormentas de polvo:
• enumerar las herramientas que están disponibles para observar las tormentas de polvo;
• describir cómo los modelos numéricos de mesoescala pueden ayudar a pronosticar las tormentas de polvo;
• enumerar los modelos de pronóstico de tormentas de polvo y describir sus respectivas ventajas.

Estimated time to complete: 2 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2009-05-06

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Description:
Este módulo explica del papel de la cizalladura del viento en la estructura y evolución de las tormentas convectivas. El módulo utiliza el concepto de vorticidad horizontal para demostrar como la cizalladura aumenta el movimiento ascendente y produce tormentas multicelulares y supercélulas de mayor duración. El módulo examina además el papel de la cizalladura en el desarrollo de los sistemas convectivos de mesoescala, incluyendo ecos en arco y líneas de turbonada. La mayor parte del material de este módulo apareció previamente en los módulos de COMET desarrollados con el Dr. Morris Weisman. Esta versión incluye un breve resumen de referencia rápida y un examen final para poner a prueba sus conocimientos.

Objectives:
Objetivo general
Al final de este módulo podrá describir el efecto de la cizalladura vertical del viento en el comportamiento de las tormentas convectivas.

Objetivos específicos
Al final de este módulo podrá:
1. describir cómo y dónde la interacción entre la corriente de salida de una tormenta (la bolsa de aire frío) y la cizalladura del viento ambiental conduce a la intensificación del ascenso y a la formación de células convectivas nuevas;
2. describir las condiciones de cizalladura vertical del viento que maximizan el ascenso a lo largo del lado de la bolsa de aire frío hacia el cual se propaga la cizalladura;
3. describir el origen de la inclinación de la corriente ascendente en una célula convectiva;
4. describir las diferentes características de cizalladura vertical de las tormentas supercelulares y los sistemas convectivos de mesoescala (SCM).

Estimated time to complete: 1.25 - 1.50 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2009-10-06

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