Near Real Time Visibility
Real-time Global Visibility
Useful as Indicator for Smoke/Haze Generated by Vegetation Fires
Weather Underground provides real-time weather conditions and forecasts for over 60,000 cities worldwide. Besides other standard ground-based meteorological information such as temperature, wind conditions and humidity, the parameter visibility is given.
Visibility, measured as horizontal visibility from the ground, can be used as an indicator for the aerosol density in the lower atmosphere since aerosols absorb and scatter light. A reduction in visibility is generally associated with the term smoke or haze. While smoke relates to aerosols from combustion processes, the term haze is frequently used to describe reduced visibility due to high humidity conditions and/or aerosols (from unspecified sources).
Vegetation fires emit large amounts of aerosols; large-scale vegetation fire incidents are therefore frequently associated with the occurence of smoke-haze events. Under these conditions, visibility can be used as an indicator for the severity of the smoke-haze.
Example of visibility map for Indonesia, 3 September 2002.
Visibility due to fires in Southern Kalimantan is reduced on Borneo island.
This information can be accessed as follows:
After entering the Weather Underground homepage at:
http://www.wunderground.com/
enter a City, State or Country. Example: Entering Indonesia will provide a link to the country web page at:
http://www.wunderground.com/cgi-bin/findweather/getForecast?query=Indonesia
Below the map all national Indonesian weather stations are linked that are part of this weather monitoring system. The overview tables include information on visibility, including haze and smoke information.
National or regional visibility maps can be accessed through the website. In the case of Indonesia click on Visibility, or directly on:
http://www.wunderground.com/global/Region/i_id/Visibility.html
The world map on the right part of the display allows direct access to other regions.
