Increasing air pollution over Asia observed by SCIAMACHY, an environmental “spy in the sky”

Results of six years space borne SCIAMACHY data

Over the past decade a strong increase in air pollution is observed over East Asia. In contrast air pollution over parts of Europe and North America has been reduced. This is one exciting result from the satellite measurements of nitrogen dioxide and other pollutants, as reported from the SCIAMACHY project.

Methane emissions as seen from the SCIAMACHY instrument, Aug.-Oct. 2004

Atmospheric composition is changing more rapidly than expected as a result of both human activities and natural processes. SCIAMACHY – an environmental instrument on board of ESA’s ENVISAT satellite – is a joint undertaking of Germany, Belgium and the Netherlands. Its sixth anniversary in space is being celebrated on the 19th of May in Vaals (NL), near to the point where the three countries join.

Air pollution in Asia and Europe
A strong increase in nitrogen dioxide is observed by SCIAMACHY in countries and areas with a booming economy, in particular in China. This increase in air pollution is a severe problem for public health and receives increased attention from the Chinese government in particular with respect to the upcoming Olympic Games. Over Western Europe SCIAMACHY has observed a stabilisation of nitrogen dioxide levels attributed partly to increased traffic, after a period of reducing nitrogen dioxide levels in the nineties resulting from EU regulations. In the Eastern USA SCIAMACHY has observed decreases in nitrogen oxide emissions related to the recent implementation of pollution controls for power plants.

In spite of the reduction of pollution over Europe, SCIAMACHY observed a combination of pollution, enhanced natural emissions and fires during the extremely warm summer of 2003 resulting in a hazardous cocktail of air pollution, which contributed significantly to the increased death toll. Climate studies predict that these warm summers will be commonplace by the middle of the century.
SCIAMACHY closely monitors key components of air pollution in particular nitrogen dioxide, which procured from traffic, power generation, and both heavy and agricultural industry and thereby an important indicator of air pollution and a cause of summer smog.

SRON built detectors for the Sciamachy instrument on ESA?s Envisat

Monitoring the Ozone layer
SCIAMACHY is providing unique information about the ozone layer – including the Ozone Hole over Antarctica – and shows first indications for its stabilisation in response to the measures enacted by the Montreal Protocol and its amendments. Recovery of the ozone layer, however, has not yet been unequivocally established. Remarkable large annual variations of the ozone hole over the Antarctic and Arctic regions are observed by SCIAMACHY, which are related to changes in atmospheric dynamics (i.e. transport and wind system). A striking example is the first ever observation of a break-up of the ozone hole in September 2002. Through SCIAMACHY, our three countries are providing a major contribution to the monitoring and assessment of the ozone layer as required by the United Nations convention.

Greenhouse Gases driving Climate Change
Carbon dioxide and methane data from SCIAMACHY have led to new insights on the emissions of methane by the tropical rainforest and wetlands and also on the seasonal and regional variations of carbon dioxide over land. This is a trail blazing application and a milestone for atmospheric remote sensing and Earth system science. SCIAMACHY is the first and so far the only satellite instrument which measures the concentrations of these greenhouse gases from the surface where emissions occur, to the top of the atmosphere.

Further Scientific Applications of SCIAMACHY
In addition to the measurements of pollution, the ozone layer, and greenhouse gases which are directly of societal significance, SCIAMACHY is making unique measurements of the changes in solar output, coronal mass ejections interaction with the upper atmosphere, meteoritic smoke clouds, and other upper atmospheric phenomena. Similarly it is providing important additional important information about ocean colour and primary production.

Future
SCIAMACHY data is secured now until 2010 and discussions on a mission extension until 2013 are ongoing within ESA and the national agencies. With the Global Monitoring for Environment and Security (GMES) programme, Europe is preparing for the operational monitoring of the atmospheric composition from space by means of the Sentinel satellites coordinated with the European operational meteorological satellite program. SCIAMACHY serves as a blue-print for these future missions. In order to avoid data gaps in the 2010-2020 decade additional follow-on missions are required.

Exploring Environmental Change: SCIAMACHY – Six years in space
The milestone of operating successfully for six years in space is being celebrated on the 19th of May in Vaals (NL). This event will be attended by the German Parliamentary State Secretary Peter Hintze, the Netherlands Ministerial Secretary General Chris Buijink, the space agencies, e. g. Agency Director N. Parmentier, Belgium, and the science team.