China

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Royal Belgian Institute for Space Aeronomy

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Sulphur dioxide emissons
from anthropogenic activities
in China

Average SO₂ distribution over China during 2004-2008.

Extract from the Wikipedia:

One of the serious negative consequences of the People's Republic of China's rapid industrial development has been increased pollution and degradation of natural resources. Much solid waste is not properly disposed of. Water pollution is a source of health problems across the country and air pollution causes up to 750,000 premature deaths each year. China's polluted environment is largely a result of the country's rapid development and consequently a large increase in primary energy consumption, which is primarily provided by coal power plants. China has pursued a development model which prioritizes exports-led growth (similar to many other East Asian countries).

Sulphur dioxide (SO₂) is one of the main constituents of air pollution over China, along with nitrogen dioxide (NO₂), carbon dioxide (CO₂), etc.

SO₂ related to anthropogenic activities will usually remain close to the ground, or more precisely: in the boundary layer (the lowest few kilometre). This means that this SO₂ can be measured from satellite only in cloud-free situations, and for that reason the daily maps of SO₂ over China show large variations.

It is therefore worthwhile to consider monthly averages. But rather than looking at the SO₂ distribution assuming the peak is at an altitude of 14 km or 6 km (respectively with the option AMF High and AMF Middle as is done for the plots shown in the archive), it is better to assume that the SO₂ is in the lowest 2 km above ground level (option AMF Low), which means that the SO₂ is found only in the planetary boundary layer - a fair assumption for SO₂ from anthropogenic activities. In addition, the colour scale is adapted to better show the SO₂ distribution. See the next two plots which show montly SO₂ vertical column for July 2010 with AMF Middle and AMF Low options (with respectively assumed peaks at 6 km and 2 km).

This page shows SO₂ averages over different periods in time based on SCIAMACHY data from the data archive, gridded on a 0.25 by 0.25 degree grid. A discussion, with some validation and trend analysis, of the data can be found in the following paper:

Zhang, X., Van Geffen, J., Zhang, P., Liao, H., Lou, S. and Van Roozendael, M.: 2009,
"Satellite observations of tropospheric SO₂ over China during 2004-2009,"
in preparation.

SCIAMACHY data

Yearly averages (AMF Low)

2004

2005

2006

2007

2008

Long-term averages ("climatologies")

all months
2004-2008

Dec-Jan-Feb
2004-2008

Mar-Apr-May
2004-2008

Jun-Jul-Aug
2004-2008

Sep-Oct-Nov
2004-2008

Monthly averages

Sequence of images of monthly averaged SO₂ for the period January 2005 up to October 2009 the variation in time of the SO₂ distribution (the images are more noisy than averages over longer periods):
> Animated GIF -- 676x480 pixels, 7.7Mb
> Animated GIF -- 344x244 pixels, 2.8Mb

In Dec. 2006 and in Nov. 2008 some SO₂ is visible to the lower left: this SO₂ is due to volcano eruptions in Africa, which was subsequently transported over a large distance.
During July-August 2005, in particular in June, a large SO₂ patch is visible to the lower right: this is due to volcanic activity at the Mariana Islands, to the south-east of the area shown in the maps.