Topic 4c - Part 1: Monitoring volcanic emissions - Overview
Remote sensing can be used to detect carbon dioxide and sulphur dioxide emissions from volcanoes. Measuring emissions from space eliminates the danger to equipment and humans that in situ measurements would face.
It is important to measure volcanic ash due to its effect on climate and airline transportation. Ash particles can abrade forward-facing surfaces, including windscreens, fuselage surfaces, and compressor fan blades on airplanes, and if sucked into an engine they can melt quickly and accumulate as re-solidified deposits in cooler parts, degrading engine performance even to the point of in-flight compressor stall and loss of thrust power. Ash can also cool the planet by shading incoming solar radiation.
Satellites are used to track the movement and extent of volcanic ash clouds and to cross-check predictions from numerical models of the spread of the ash. The geostationary Meteosat satellites can detect ash in the atmosphere and play an important role in following its movement and dispersion in European airspace, in near real-time. The Metop satellites with the aid of the IASI, GOME-2 and AVHRR instruments, are able to collect more detailed data about volcanic ash clouds, including sulphur dioxide, ash and ice content, but with less frequency as they only pass over the same area roughly twice a day.
In the 2021-40 timeframe, the next generations of EUMETSAT’s Meteosat and Metop satellites will provide even more detailed, higher resolution data to monitor volcanic ash and other types of aerosols.
EUMETSAT’s Meteosat Third Generation (MTG) satellites will be crucial to volcanic ash monitoring with their higher resolution and more frequent imagery and new sounding capabilities. In addition to improved imagery at 10-minute repeat cycles, the provision of data from the MTG infrared and Sentinel-4 ultraviolet/visible sounding missions will be crucial for volcanic ash modelling.
Dr Kenneth Holmlund
Dr Johannes Flemming
Optional mini task
Volcanic ash creates a number of risks; one such risk is to the navigation of aircraft. In the past unexpected encounters with volcanic ash have caused damage to numerous aircraft including in-flight loss of jet engine power, which put the lives of all passengers and crew at risk. Therefore, being able to monitor volcanic ash is essential in being able to ensure safe flying conditions.
EUMETSAT has created an informative 60-minute training module on volcanic ash. This training module is dedicated to forecasters/aviation forecasters. The main intention is to provide a guideline on how to assess the potential of hazardous weather events such as volcanic ash. Click here to begin the training module.
Don’t forget you can download the video, transcript and take any quizzes available with the links on the right.
The image on the top left is a true colour image from MODIS aboard NASA’s Aqua satellite, showing the Sinabung eruption. The image on the top right is the same view but showing the sulphur dioxide in purple. The bottom image is a cross section of the eruption area which shows the ash cloud in red.