Topics


Basic Satellite and NWP Integration
NWP is one of the most important forecasting tools in our toolbox. Yet identifying when/where it isn’t capturing reality is difficult. In the short-term forecasting range, it is important as a forecaster to identify when/where NWP output isn’t matching reality. Then you can make appropriate changes to the forecast output. To find those mismatches anywhere in the world, one of the best tools is satellite imagery. In this lesson, we will focus on a few cases using satellite imagery to help identify mismatched features/processes between the satellite imagery and the NWP. Anyone trying to add valu ...
Available online: https://www.meted.ucar.edu/training_module.php?id=1408
Published by: The University Corporation for Atmospheric Research ; 2019
NWP is one of the most important forecasting tools in our toolbox. Yet identifying when/where it isn’t capturing reality is difficult. In the short-term forecasting range, it is important as a forecaster to identify when/where NWP output isn’t matching reality. Then you can make appropriate changes to the forecast output. To find those mismatches anywhere in the world, one of the best tools is satellite imagery. In this lesson, we will focus on a few cases using satellite imagery to help identify mismatched features/processes between the satellite imagery and the NWP. Anyone trying to add value to short-term NWP forecasts could benefit from taking this lesson to learn a process for assessing NWP output compared to observations. This lesson focuses on fog and convection in Africa, however this lesson can apply to many other cases, and is generalized enough to help forecasters from anywhere in the world.
Disclaimer regarding 3rd party resources: WMO endeavours to ensure, but cannot and does not guarantee the accuracy, accessibility, integrity and timeliness of the information available on its website. WMO may make changes to the content of this website at any time without notice.
The responsibility for opinions expressed in articles, publications, studies and other contributions rests solely with their authors, and their posting on this website does not constitute an endorsement by WMO of the opinion expressed therein.
WMO shall not be liable for any damages incurred as a result of the use of its website. Please do not misuse our website.Language(s): English
Format: Digital (Standard Copyright)Tags: Weather forecasting ; Numerical weather prediction ; Fog ; Convection ; Lesson/ Tutorial ; NWP Skills and Knowledge for Operational Meteorologists ; Satellite Skills and Knowledge for Operational Meteorologists
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Rapid Scan Applications and Benefits
This lesson introduces the capabilities and benefits of rapid scan imaging from geostationary meteorological satellites with a special focus on the current Meteosat Second Generation satellites. The lesson begins with an overview of current rapid scan imaging strategies and the products made from those observations. It then addresses nowcasting applications that benefit from these products with a focus on convection and its evolution. Other application areas that benefit from rapid scan observation are mentioned including the monitoring of fog and low stratus, wildfires, tropical cyclones, and ...
Available online: https://www.meted.ucar.edu/training_module.php?id=1322
Published by: The University Corporation for Atmospheric Research ; 2018
This lesson introduces the capabilities and benefits of rapid scan imaging from geostationary meteorological satellites with a special focus on the current Meteosat Second Generation satellites. The lesson begins with an overview of current rapid scan imaging strategies and the products made from those observations. It then addresses nowcasting applications that benefit from these products with a focus on convection and its evolution. Other application areas that benefit from rapid scan observation are mentioned including the monitoring of fog and low stratus, wildfires, tropical cyclones, and atmospheric motion vector data. The final section describes the new and next-generation rapid scan datasets from international satellite operators around the world and improvements for advancing weather analysis and prediction.
Disclaimer regarding 3rd party resources: WMO endeavours to ensure, but cannot and does not guarantee the accuracy, accessibility, integrity and timeliness of the information available on its website. WMO may make changes to the content of this website at any time without notice.
The responsibility for opinions expressed in articles, publications, studies and other contributions rests solely with their authors, and their posting on this website does not constitute an endorsement by WMO of the opinion expressed therein.
WMO shall not be liable for any damages incurred as a result of the use of its website. Please do not misuse our website.Language(s): English
Format: Digital (Standard Copyright)Tags: Weather forecasting ; Fog ; Lesson/ Tutorial ; Satellite Skills and Knowledge for Operational Meteorologists
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SatFC-J: The VIIRS Day/Night Band
This lesson introduces the innovative Day/Night Band (DNB). Producing both daytime and nighttime visible images, the unique aspect of the DNB is its nocturnal low-light imaging capability. It views reflected moonlight from clouds and Earth's surface, surface light emissions from various natural sources (such as fires) and anthropogenic sources (such as city lights and gas flares), and even from certain atmospheric light emissions such as the aurora, airglow, and lightning flashes. The lesson describes the capabilities and benefits of the DNB, in particular using the Near-Constant Contrast (NCC ...
Available online: https://www.meted.ucar.edu/training_module.php?id=1310
Published by: The University Corporation for Atmospheric Research ; 2018
This lesson introduces the innovative Day/Night Band (DNB). Producing both daytime and nighttime visible images, the unique aspect of the DNB is its nocturnal low-light imaging capability. It views reflected moonlight from clouds and Earth's surface, surface light emissions from various natural sources (such as fires) and anthropogenic sources (such as city lights and gas flares), and even from certain atmospheric light emissions such as the aurora, airglow, and lightning flashes. The lesson describes the capabilities and benefits of the DNB, in particular using the Near-Constant Contrast (NCC) product, available in the NWS' AWIPS-2 (Advanced Weather Interactive Processing System). It also explores key features that can be seen in DNB imagery throughout the lunar cycle, and some practical uses of this imagery. This lesson is part of the Satellite Foundational Course for JPSS (SatFC-J).
Disclaimer regarding 3rd party resources: WMO endeavours to ensure, but cannot and does not guarantee the accuracy, accessibility, integrity and timeliness of the information available on its website. WMO may make changes to the content of this website at any time without notice.
The responsibility for opinions expressed in articles, publications, studies and other contributions rests solely with their authors, and their posting on this website does not constitute an endorsement by WMO of the opinion expressed therein.
WMO shall not be liable for any damages incurred as a result of the use of its website. Please do not misuse our website.Language(s): English
Format: Digital (Standard Copyright)Tags: Weather forecasting ; Aurora ; Fog ; Lesson/ Tutorial ; Arctic ; Satellite Skills and Knowledge for Operational Meteorologists
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GOES-R Series Faculty Virtual Course: Multispectral RGB Composites
In this webinar recording Dr. Emily Berndt and Dr. Michael Folmer discuss the capabilities of the GOES-R/16 Red-Green-Blue (RGB) composites. Multispectral or RGB composites are qualitative, false color images designed to enhance specific features in the atmosphere that are important to forecasters, aviators, mariners, and emergency response officials. RGB composites have been enthusiastically integrated into forecast operations because of their ability to highlight the presence and evolution of important forecast phenomena. This presentation details the development of RGB composites and provid ...
Available online: https://www.meted.ucar.edu/training_module.php?id=1380
Published by: The University Corporation for Atmospheric Research ; 2017
In this webinar recording Dr. Emily Berndt and Dr. Michael Folmer discuss the capabilities of the GOES-R/16 Red-Green-Blue (RGB) composites. Multispectral or RGB composites are qualitative, false color images designed to enhance specific features in the atmosphere that are important to forecasters, aviators, mariners, and emergency response officials. RGB composites have been enthusiastically integrated into forecast operations because of their ability to highlight the presence and evolution of important forecast phenomena. This presentation details the development of RGB composites and provide examples of RGB use for atmospheric dust, volcanic ash, cyclogenesis, air mass characteristics, fog, and low clouds. This is a recorded webinar presented by instructors at their home institutions. Audio variations may exist.
Disclaimer regarding 3rd party resources: WMO endeavours to ensure, but cannot and does not guarantee the accuracy, accessibility, integrity and timeliness of the information available on its website. WMO may make changes to the content of this website at any time without notice.
The responsibility for opinions expressed in articles, publications, studies and other contributions rests solely with their authors, and their posting on this website does not constitute an endorsement by WMO of the opinion expressed therein.
WMO shall not be liable for any damages incurred as a result of the use of its website. Please do not misuse our website.Language(s): English
Format: Digital (Standard Copyright)Tags: Weather forecasting ; Fog ; Lesson/ Tutorial ; Aviation ; Satellite Skills and Knowledge for Operational Meteorologists
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Advances in Space-Based Nighttime Visible Observation, 2nd Edition
This updated one-hour lesson explores the types of atmospheric and surface features that can be observed at night. It describes recent technical improvements in nighttime visible imaging with the VIIRS Day/Night Band on board the Suomi NPP and JPSS satellites, and the lunar phases and other conditions necessary for effective nighttime visible imaging. This lays the foundation for the rest of the lesson, which explores operational uses of nighttime visible observations. These include the detection and monitoring of city lights, tropical cyclones, fog and stratus, polar nights, auroras, fires an ...
Available online: https://www.meted.ucar.edu/training_module.php?id=1327
Published by: The University Corporation for Atmospheric Research ; 2017
This updated one-hour lesson explores the types of atmospheric and surface features that can be observed at night. It describes recent technical improvements in nighttime visible imaging with the VIIRS Day/Night Band on board the Suomi NPP and JPSS satellites, and the lunar phases and other conditions necessary for effective nighttime visible imaging. This lays the foundation for the rest of the lesson, which explores operational uses of nighttime visible observations. These include the detection and monitoring of city lights, tropical cyclones, fog and stratus, polar nights, auroras, fires and smoke, volcanic eruptions, dust storms, air pollution, moon glint, lightning, gas flares, ships and boats, and population/economic geography. The lesson is intended for weather forecasters and other environmental scientists who use nighttime environmental data. Other users, such as those in the transportation industry and economists, may benefit from it as well.
Disclaimer regarding 3rd party resources: WMO endeavours to ensure, but cannot and does not guarantee the accuracy, accessibility, integrity and timeliness of the information available on its website. WMO may make changes to the content of this website at any time without notice.
The responsibility for opinions expressed in articles, publications, studies and other contributions rests solely with their authors, and their posting on this website does not constitute an endorsement by WMO of the opinion expressed therein.
WMO shall not be liable for any damages incurred as a result of the use of its website. Please do not misuse our website.Language(s): English
Format: Digital (Standard Copyright)Tags: Air pollution ; Weather forecasting ; Aurora ; Fog ; Lesson/ Tutorial ; Arctic ; Satellite Skills and Knowledge for Operational Meteorologists
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GOES-R Series Faculty Virtual Course: Aviation Products
In this webinar recording, Amanda Terborg (with input from Dr. Chad Gravelle), will demonstrate the capabilities of GOES-R/16 in analyzing hazards affecting the aviation industry. The talk focuses specifically on four hazards (but there are others): 1) fog and low stratus, 2) in-flight turbulence, 3) dust, and 4) volcanic ash. Through the use of GOES-R/16 spectral bands, band differences, and RGB composites, satellite data users can detect the development and evolution of aviation threats better than with any previous geostationary satellites. This is a recorded webinar presented by an instruc ...Permalink![]()
Forecasters' Overview of the Mediterranean and Europe
This module provides an introduction to the European continent and the Mediterranean and Black Sea areas for weather forecasters. It focuses on geography, climatology, oceanography, major aspects of the synoptic and mesoscale weather patterns, and hazards to aviation and maritime operations. Geography covers major political boundaries, cities, ports, topographical features, rivers, and volcanic areas. Climatology covers the seasonal climatology of jet stream, synoptic weather systems, extratropical cyclones, and high winds and seas. Oceanography includes major bathymetric features; mean sea su ...Permalink![]()
Fogbows
Porto Roberto - WMO, 2016"- Location name, latitude and longitude (map entry tool available) Teide National Park Tenerife Spain
latitude 28°16'51.83"N longitude 16°34'27.76"w
- Climate Classification (Koppen scheme ; map entry available) BSh
- Type of location (land/sea or air): land/sea
- Camera pointing direction.west
- Meteor type (e.g. clouds, lithometers, etc.) atmospheric optic : fogbows
- Cloud Genera (e.g. Cirrocumulus, unknown, etc.) fogbows
metadata : nikon d5300 with nikkor fish eye (ultra wide )"Permalink![]()
Fog Forecasting for Heathrow, Northolt and Kenley Aerodromes Using Model Output Statistics
Fog though a rare event has adverse economic implications to both the airline and aviation service providers if it’s occurrence, duration and dissipation periods are not properly predicted. This work assesses the accuracy and skill in forecasting fog events and suggesting possible adjustments to improve forecast accuracy and skill. The forecast used in this study are produced by MeteoGroup using Model Output Statistics (MOS). Forecasts for Heathrow, Northolt and Kenley are considered for analysis. These forecasts are used by British Airports Authority (BAA) in planning airport operations. The ...Permalink![]()
The impacts of fog and thunderstorms on aircraft operations : a case study of Wilson Airport Nairobi Kenya
Abongnwi Ngwa Lumfuh - 2014Adverse weather is the main cause of the alterations to operations at Wilson airport. At Wilson airport, occurrence of fog and low ceiling, cross winds, thunderstorm and heavy rainfall are considered the main causes of adverse weather hampering the aircraft operations. The purpose of this study is to investigate the impacts of fog and thunderstorm on aircraft operations at Wilson airport. The impact is measured in terms of delay, diversion, cancelation and economic value of these actions. The data on fog and thunderstorm data was obtained from Kenya Meteorological Service (Climatological secti ...Permalink![]()
Multispectral Satellite Applications: RGB Products Explained
This lesson provides an overview of meteorological and environmental RGB products, namely, how they are constructed and how to use them. The first half provides background information on the RGB development process and the rapid evolution of RGB products as newer geostationary and polar-orbiting satellite imagers incorporate additional spectral channels. The second half of the lesson, the Applications section, focuses on the formulation and uses of RGB products; providing examples, interpretation exercises, satellite specific information, and other background information for many of the common ...Permalink![]()
Writing TAFs for Ceilings and Visibility, Africa Edition
Writing TAFs for Ceilings and Visibility, Africa Edition outlines the processes for developing an effective Terminal Aerodrome Forecast (TAF) that meets International Civil Aviation Organization (ICAO) guidelines. Geared specifically to forecasters in Africa, the lesson includes a case study for an event impacting Cape Town International Airport to provide practice applying the processes to real-life forecast situations.Permalink![]()
Tropical Fog: A Look at Fog That Impacts Aviation in Guyana
This module applies concepts covered in the module, Fog: Its Processes and Impacts to Aviation. It examines the fog processes at a tropical location: Guyana. A basic overview of the main fog types is provided, and then a detailed analysis is done for a representative fog event at the Cheddi Jagan International Airport in Guyana. Conclusions are made about fog processes in Guyana which can then be applied to forecasting for aviation impacts.Permalink![]()
ASMET 7: Forecasting Fog for Aviation: Kenya Case Study
This lesson aims to improve aviation forecasts of fog in the African airspace by teaching forecasters to make more accurate forecasts using satellite imagery, numerical weather prediction, and other available data. A process for diagnosing and forecasting fog is presented and applied to a case over the Nairobi, Kenya region. Learners assume the role of aviation forecaster, analysing various products to determine whether the current Terminal Aerodrome Forecast (TAF) is valid or needs to be amended. The lesson is intended for aviation forecasters, general weather forecasters interested in aviati ...Permalink![]()
Introduction to VIIRS Imaging and Applications
This lesson introduces the VIIRS imager that operates on the current U.S. Suomi NPP satellite and is planned for future JPSS environmental satellites. VIIRS has many advanced features that improve both spectral and spatial resolution and enable the delivery of consistent, high quality, and high resolution data to users worldwide. The lesson covers the enhanced capabilities of VIIRS and highlights some of its applications. These include single channel and multispectral products used to monitor dust, volcanic ash, convection, fog and low clouds, sea surface temperature, tropical cyclones, contra ...Permalink![]()
Weather Decision Support for the National Airspace System
This three-hour lesson describes the impacts of weather on aviation operations and highlights the role of the National Weather Service (NWS) in supporting the Federal Aviation Administration's air traffic management organization. The lesson contains an Introduction (40 min), several cases (10-20 min each) focused on various weather phenomena, and a detailed case (35 min) allowing forecasters to follow the planning for and evolution of an event. The content emphasizes best practices for aviation forecasters, including identifying and communicating the threat, understanding partners' needs, and ...Permalink![]()
GOES-R ABI: Next Generation Satellite Imaging
This extension of the COMET lesson “GOES-R: Benefits of Next Generation Environmental Monitoring” focuses on the ABI instrument, the satellite's 16-channel imager. With increased spectral coverage, greater spatial resolution, more frequent imaging, and improved image pixel geolocation and radiometric performance, the ABI will bring significant advancements to forecasting, numerical weather prediction, and climate and environmental monitoring. The first part of the lesson introduces the ABI's key features and improvements over earlier GOES imagers. The second section lets users interactively ex ...Permalink![]()
Arctic Meteorology and Oceanography
Diminishing sea ice has opened the Arctic to navigation and operations like never before. Forecasters are increasingly predicting weather in support of those operations. This module is intended to provide forecasters with a brief introduction to the Arctic, including its geography, climatology, and the forecast problems they are likely to encounter. The module follows a U.S. Coast Guard Cutter on a voyage from Dutch Harbor, in the Aleutian Islands, to Barrow, on the north coast of Alaska. Various topics are addressed along the way in a series of short, stand-alone lessons.Permalink![]()
Remote Sensing Using Satellites, 2nd Edition
The second edition of the popular "Remote Sensing Using Satellites" module updates imagery of recent hurricanes as well as other phenomena from more recent satellites. The suggested audience for this module is high school and undergraduate students. Learn about remote sensing in general and then more specifically about how it is done from satellites. We will focus on the visible and infrared channels, those commonly seen on television broadcasts. Come explore the view of Earth from space and see what we see. In the second chapter, we will focus even more on hurricanes and specifically Hurrican ...Permalink![]()
Satellite Meteorology: GOES Channel Selection V2
This module is an update to the previous Satellite Meteorology: GOES Channel Selection module. It reviews the five GOES imager channels and their use, incorporating conceptual visualizations and numerous imagery examples. The module also includes updated information on improvements for the GOES-13, -14 and -15 satellites. Highlights include a higher resolution 13.3 micrometer CO2 channel (GOES-14 & -15), modified spectral response of the visible channel, improved radiometric performance and pixel geolocation, and shortened data outages during the fall and spring satellite eclipse periods.Permalink![]()
Role of the Skywarn Spotter
The goal of the "Role of the SKYWARN® Spotter" module is to provide baseline training for all spotters through multiple scenarios covering the procedures for spotting (including communication and storm report criteria), safety considerations for all hazards, and an overview of the national program and its history.Permalink![]()
Writing TAFS for Ceilings and Visibility
"Writing TAFs for Ceilings and Visibility" is the fifth unit in the Distance Learning Aviation Course 2 (DLAC2) series on producing TAFs that meet the needs of the aviation community. In addition to providing information about tools for diagnosing low ceilings and reduced in visibility and its related impacts, the module extends the Practically Perfect TAF (PPTAF) process to address an airport's operational thresholds. By understanding the thresholds at airports for which they produce TAFs, forecasters will be better able to produce a PPTAF. The unit also examines how to communicate effectivel ...Permalink![]()
Fog: Its Processes and Impacts to Aviation and Aviation Forecasting
This module first introduces forecasters to aviation-forecast customers and their needs, and discusses how fog impacts aviation operations. The main content of the module then explains the physical processes and life cycle of radiation and advection fog, including their preconditioning environment, initiation, growth, and dissipation. The processes covered in the module include radiation (both solar and longwave), soil-atmosphere thermal interactions, turbulent mixing, the roles of condensation nuclei, and droplet settling. Each section of the module includes a set of interactive questions bas ...Permalink![]()
BoM Aviation Fog Case Exercise
This case exercise focuses on a potential fog event in Melbourne, Australia, on 6-7 April 2008. The key aim of this module is to step through the forecast process during a potential fog event from the perspective of an aviation forecaster with the Australian Bureau of Meteorology. This involves consideration of model guidance and observations, identification of potential areas of fog, forecasting and nowcasting fog formation and clearance, and considering and providing TAF updates throughout.Permalink![]()
Fourth International Conference on fog, fog collection and dew - program and abstracts
World Meteorological Organization (WMO) ; Instituto de Geografía Universidad Católica de Chile; Atacama Desert Center (ADC); et al. - Universidad Católica de Chile, 2009Permalink![]()
GOES-R: Benefits of Next-Generation Environmental Monitoring
This module is an introduction to NOAA's next generation Geostationary Operational Environmental Satellite-R (GOES-R) series, focusing on the value and anticipated benefits derived from an enhanced suite of instruments for improved monitoring of meteorological, environmental, climate, and space weather phenomena and related hazards. An extensive set of visualizations highlight GOES-R and its advanced observing capabilities for providing support in thirteen key environmental application areas including air quality and visibility, climate, cloud icing, fires, hurricanes, land cover, lightning, l ...Permalink![]()
Dynamically Forced Fog
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.Permalink![]()
Applying Diagnostic and Forecast Tools: Forecasting Fog and Low Stratus
This module discusses how to apply various observational data and remote sensing tools such as satellite, METARS, soundings, profilers, radar, and model analyses to diagnose the potential for fog and/or low stratus. Various forecast tools (such as model forecast fields, forecast soundings, and BUFKIT) used to assess fog and/or low stratus potential onset, intensity, and duration are also examined. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.Permalink![]()
Writing Effective TAFs
This module provides an overview of some of the applicable TAF Amendment and Conditional Group usage rules, as presented in the latest version of the National Weather Service Instruction 10-813 on TAF directives. It also presents a methodology for TAF writing and development that will lead to an effective and user-friendly product. The focus is on the ceiling and visibility aspects of the TAF. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.Permalink![]()
Synoptic Weather Considerations: Forecasting Fog and Low Stratus
In order to assess whether a fog or stratus event is possible, you must evaluate the synoptic-scale influences that will drive the local conditions. In this module, we examine several common synoptic situations to understand the processes involved in fog or low stratus development. Most of these are forced primarily by advective or dynamic processes (although radiation does play a role). A more detailed discussion of radiation processes is contained in the Radiation Fog module. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.Permalink![]()
Local Influences on Fog and Low Stratus
Local and mesoscale influences can make or break your fog or stratus forecast. Influences of local water bodies, terrain, vegetation, soil characteristics, and coastal features on the lower atmosphere can play a vital role in the development, duration, and intensity of these events. As part of the Distance Learning Course 1: Forecasting Fog and Low Stratus, this module examines several of these influences and discusses how they enhance or inhibit a fog or stratus event.Permalink![]()
Customer Impacts: Forecasting Fog and Low Stratus
This module addresses issues surrounding the direct and indirect impacts of restricted ceilings and visibilities on aviation operations and also briefly examines their impacts on ground and marine transportation. The goal is improve forecaster awareness of how their forecasts of these events affect commercial and general aviation operation. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.Permalink![]()
Remote Sensing of Land, Oceans, and Atmosphere with MODIS
This Webcast is based on presentations given by Dr. W. Paul Menzel at several conferences. It is approximately 60 minutes in length and introduces the MODIS instrument on the Terra satellite. Dr. Menzel begins by providing background on MODIS channel selection and instrument calibration. He continues with a variety of examples that include both climatological and meteorological applications, including high-resolution data and derived-product imagery. The examples are divided into land, ocean, and atmosphere applications. Dr. Menzel concludes with a discussion of the new direct-broadcast capabi ...Permalink![]()
Thermally-forced Circulation II: Mountain/Valley Breezes
This is a foundation module in the Mesoscale Meteorology Primer series. Topics covered include up- and downslope breezes, up- and down-valley winds, associated hazards, and forecasting techniques. Like other modules in the Mesoscale Meteorology Primer, this module comes with audio narration, rich graphics, and a companion print version.Permalink![]()
West Coast Fog
This is part of the Physical Processes Professional Competency Unit of the Forecasting Low-Altitude Clouds and Fog for Aviation Operations Professional Development Series. West Coast Fog discusses the climatology, physical processes, and evolution of hot spell fogs along the U.S. West Coast.Permalink![]()
Keynote address at the opening of the WMO Workshop on Regional Transboundary Smoke and Haze in South-East Asia
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