Forest fires at Greece seen from space

The forest fires, which had already plagued Greece for the entire summer, have increased in size and fierceness again in the past days. These fires that have killed at least 60 people ravaged large areas of countryside and even complete villages have been destroyed.

From space the satellite instruments SCIAMACHY and OMI measure the concentration nitrogen dioxide (NO2) and formaldehyde emitted by these fires.

During forest fires the gases formaldehyde and NO2 are formed. The gas NO2, which is toxic at high concentrations, plays an important role in the creation of smog and it has a direct effect on the air quality in the troposphere. The most important contribution of tropospheric NO2 is human-induced such as traffic, heavy industry, and biomass burning. The concentrations of NO2 above Greece as measured by OMI are comparable to those of the most polluted areas in the world.

With the satellite instruments SCIAMACHY (SCanning Imaging Absorption spetroMeter for Atmospheric CartograpHY) and OMI (Ozone Monitoring Instrument) it is also possible to analyse the chemical composition of the plume. The instruments are capable of measuring the concentration NO2, formaldehyde, ozone and other trace gases in the atmosphere.

Besides NO2 many other atmospheric components are measured by satellites. One of them is the amount of aerosols in the atmosphere. Aerosols are very small particles in the air caused for example by desert storms, volcanic eruptions, industrial activities and also by forest fires. Because aerosols absorb sunlight and play a role in cloud formation, they have a central role in climate processes.

The OMI observations show the large concentrations of NO2 produced by the forest fires in Greece. Because of the strong north-easterly winds a large plume was forming over sea in the direction of the Libyan coast. Each image shows the situation of a single day.

The formaldehyde concentrations as measured by SCIAMACHY on 26 August 2007 superimposed over an image made by TERRA-MODIS (Source: Earth Observatory) Due to the strong north-easterly wind the smoke from the forest fires is blown all the way to the coast of Lybia.

This image of the aerosol index measured by the OMI instrument on 25 August 2007 clearly shows the soot of the fires blown from the Peloponnesus in Greece to Libya.