Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Three ESA satellites reveal Etna’s complexity

31.10.2002


As detected by ESA satellite sensors, the recent eruptions of the Mount Etna volcano in Sicily are throwing huge amounts of ash and trace gases into the atmosphere. Working with data from the Global Ozone Monitoring Experiment (GOME) sensor onboard ESA’s ERS-2 spacecraft, scientists at the German aerospace centre (DLR) report that levels of sulphur dioxide from the eruptions on Sunday and Monday are at least 20 times higher than normal.


A plume of smoke and ash from Sicily’s Mount Etna is seen in this image acquired 28 October 2002 by the Medium Resolution Imaging Spectrometer (MERIS) instrument onboard ESA’s Envisat Satellite
Credits: ESA



As detected by ESA satellite sensors, the recent eruptions of the Mount Etna volcano in Sicily are throwing huge amounts of ash and trace gases into the atmosphere. Sensors onboard three different ESA spacecraft have acquired imagery of the eruptions that shed new light on the event and its impact on the Earth’s environment.
Working with data from the Global Ozone Monitoring Experiment (GOME) sensor onboard ESA’s ERS-2 spacecraft, scientists at the German aerospace centre (DLR) report that levels of sulphur dioxide from the eruptions on Sunday and Monday are at least 20 times higher than normal.

This latest activity from Mt. Etna, the second in a little over a year, marks the beginning of another period of activity of Europe’s largest volcano, says Werner Thomas, an atmospheric scientist with DLR’s Remote Sensing Technology Institute.



“As in July and August 2001 eruptions of Etna, dense ash clouds and gaseous emissions were again detected by several space-borne sensors,” he said.

The normal background level of sulphur dioxide is typically below 0.5 Dobson Units (DU), a measure of atmospheric gas concentrations from ground level to the top of the atmosphere, about 70 km in altitude.

"In the plume, we measured atmospheric content of sulphur dioxide of about 10 DU, at least 20 times higher than normal," Thomas said.

Sulphur dioxide in the troposphere, the lowest part of the atmosphere where most weather changes occur, is known to be responsible for the so-called "acid rain" phenomenon. Stratospheric sulphur dioxide, from about 11 km to 50 km above the Earth’s surface, causes the formation of sulphate aerosol particles that may have a serious impact on the global climate. Mt. Etna is one of the most prominent sources of natural sulphur dioxide worldwide.

The ERS’ GOME instrument is dedicated for remote sensing of the atmosphere and can detect a variety of atmospheric trace gases, including sulphur dioxide. The first GOME data after the beginning of the eruptions was recorded and analysed on 29 October around 10:15 UTC. As seen in the accompanying chart, enhanced levels of sulphur dioxide are evident in the southeast of Sicily, indicating that the tropospheric sulphur dioxide was carried away from the volcano by the winds in that direction.

The Italian government declared a state of emergency yesterday in Sicily in the wake a series of earthquakes, measuring between 3.6 and 4.3 on the Richter scale, that forced the evacuation of approximately 1 000 homes, according to reports from BBC and Italian newspapers. Meanwhile, three streams of lava from the eruption flowed down the south, northeast and northwest slopes of the mountains, media reports stated.

Europe’s highest and most active volcano (3370 m) hurled lava and ash from several craters into the sky with a speed between 350 and 450 metres per second, exceeding the speed of sound. According to data from volcanologists, the lava and ash were ejected from the main crater and from at least nine new craters that developed in the mountain between 2300 to 2700 metres in altitude.

As seen in the image acquired Monday by the Medium Resolution Imaging Spectrometer (MERIS) onboard ESA’s Envisat satellite, the eruptions spewed significant amounts of ash, along with sulphur dioxide, into the atmosphere The plume from the volcano can be seen in the image stretching south and west from Sicily to the north African coast. The larger volcanic ash particles are expected to settle out in a short period of time, but the sulphuric acid aerosols produced by the sulphur dioxide will persist for several years.

These aerosols will impact the Earth’s energy budget, both regionally and on a global scale. Aerosols containing black graphite and carbon particles are dark, thus absorbing sunlight. As these atmospheric particles reduce the amount of sunlight reaching the planet’s surface, they increase the amount of solar energy absorbed in the atmosphere, thus simultaneously cooling the surface and warming the atmosphere.

The capability of the MERIS instrument to observe the spatial distribution of these aerosol plumes can be exploited to measure the amounts of airborne particles and to examine the role of these aerosols as cloud condensation nuclei and their impact on the hydrologic cycle through changes in cloud cover, cloud properties and precipitation.

Today’s images from Proba

Just 60x60x80 cm and weighing only 94 kg, ESA’s Project for On-Board Autonomy satellite, better known as Proba, is one of the most advanced small satellites ever flown in space.

Since its launch last year, Proba’s high-performing computer system and technologically advanced instruments have enabled it to demonstrate and evaluate onboard operational autonomy, new spacecraft technology both hardware and software, and to test Earth observation and space environment instruments in space.

The imagery captured today by Proba demonstrate the capabilities of CHRIS, the Compact High Resolution Imaging Spectrometer, which is providing important information on the Earth and its environment, and will be a valuable tool in remote sensing during the extended mission.

The instrument acquired the accompanying Etna images in four standard bands, although the instrument is capable of image acquisition in up to 19 different bands.

Erica Rolfe | ESA

More articles from Earth Sciences:

nachricht 'Quartz' crystals at the Earth's core power its magnetic field
23.02.2017 | Tokyo Institute of Technology

nachricht NASA spies Tropical Cyclone 08P's formation
23.02.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

From rocks in Colorado, evidence of a 'chaotic solar system'

23.02.2017 | Physics and Astronomy

'Quartz' crystals at the Earth's core power its magnetic field

23.02.2017 | Earth Sciences

Antimicrobial substances identified in Komodo dragon blood

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>