Steffen Beirle

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Megacities are immense sources of air pollutants, with large impacts on air quality and climate. However, emission inventories in many of them still are highly uncertain, particularly in developing countries. Satellite observations allow top-down estimates of emissions to be made for nitrogen oxides (NO(x) = NO + NO(2)), but require poorly quantified a(More)
In May 2003, severe forest fires in southeast Russia resulted in smoke plumes extending widely across the Northern Hemisphere. This study combines satellite data from a variety of platforms (Moderate Resolution Imaging Spectroradiometer (MODIS), Sea-viewing Wide Field-ofview Sensor (SeaWiFS), Earth Probe Total Ozone Mapping Spectrometer (TOMS) and Global(More)
The Global Ozone Monitoring Experiment (GOME) allows the retrieval of tropospheric vertical column densities (VCDs) of NO2 on a global scale. Regions with enhanced industrial activity can clearly be detected, but the standard spatial resolution of the GOME ground pixels (320×40 km2) is insufficient to resolve regional trace gas distributions or individual(More)
A solution is proposed of the hitherto unsolved problem as to how neural feedforward through inverse modelling and negative feedback realised by a mechanical spring can be combined to achieve a highly effective control of limb movement. The revised spring approach that we suggest does not require forward modelling and produces simulated data which are as(More)
Nitrogen oxides (NOx=NO+NO2) play an important role in tropospheric chemistry, in particular in catalytic ozone production. Lightning provides a natural source of nitrogen oxides, dominating the production in the tropical upper troposphere, with strong impact on tropospheric ozone and the atmosphere’s oxidizing capacity. Recent estimates of lightning(More)
Intercontinental transport (ICT) of trace substances normally occurs on timescales ranging from a few days to several weeks. In this paper an extraordinary episode in November 2001 is presented, where pollution transport across the North Atlantic took only about one day. The transport mechanism, termed here an intercontinental pollution express highway(More)
In the field, aerosol in-situ measurements are often performed under dry conditions (relative humidity RH<30– 40%). Since ambient aerosol particles experience hygroscopic growth at enhanced RH, their microphysical and optical properties – especially the aerosol light scattering – are also strongly dependent on RH. The knowledge of this RH effect is of(More)
We present a new concept to determine atmospheric photon path lengths from satellite observations with moderate spectral resolution like GOME and SCIAMACHY. From such instruments it is possible to measure the atmospheric absorptions of the oxygen molecule and its dimer at several wavelengths. Together with the simultaneously measured radiance (top of the(More)
The Global Ozone Monitoring Experiment (GOME, since 1995) allows the retrieval of global total column densities of atmospheric trace gases, including NO 2. Tropospheric vertical column densities (VCDs) are derived by estimating the stratospheric fraction from measurements over the remote ocean. Mean maps of tropospheric NO 2 VCDs 5 derived from GOME clearly(More)