We have studied the vertical structure of hazes at six different latitudes (−60◦, −50◦, −30◦, −10◦, +30◦, and +50◦) on Saturn’s atmosphere. For that purpose we have compared the results of our forward radiative transfer model to limb-to-limb reflectivity scans at four different wavelengths (230, 275, 673.2, and 893 nm). The images were obtained with the Hubble Space Telescope Wide Field Planeta...

[1] Tropospheric ozone and aerosols are radiatively important trace species, whose concentrations have increased dramatically since preindustrial times and are projected to continue to change in the future. The evolution of ozone and aerosol concentrations from 1860 to 2100 is simulated on the basis of estimated historical emissions and four different future emission scenarios (Intergovernmenta...

We use a Lagrangian chemical transport model with a Monte Carlo approach to determine impacts of kinetic rate uncertainties on simulated concentrations of ozone, NOy and OH in a high-altitude biomass burning plume and a low-level industrial pollution plume undergoing long-range transport. Uncertainties in kinetic rate constants yield 10–12 ppbv (5th to 95th percentile) uncertainty in the ozone ...

Atmospheric iodine monoxide (IO) is a radical that catalytically destroys heat trapping ozone and reacts further to form aerosols. Here, we report the detection of IO in the tropical free troposphere (FT). We present vertical profiles from airborne measurements over the Pacific Ocean that show significant IO up to 9.5 km altitude and locate, on average, two-thirds of the total column above the ...

The El Niño–Southern Oscillation (ENSO) not only affects meteorological fields but also has a large impact on atmospheric composition. Atmospheric composition fields from the Monitoring Atmospheric Composition and Climate (MACC) reanalysis are used to identify the ENSO signal in tropospheric ozone, carbon monoxide, nitrogen oxide and smoke aerosols, concentrating on the months October to Decemb...

Tropospheric NO2 plays a variety of significant roles in atmospheric chemistry. In the troposphere it is one of the most significant precursors of photochemical ozone (O3) production and nitric acid (HNO3). In this study tropospheric NO2 columns were calculated by the fully coupled chemistry-climate model ECHAM4.L39(DLR)/CHEM. These have been compared with tropospheric NO2 columns, retrieved us...

We present a comprehensive description and benchmark evaluation of the tropospheric chemistry version of the global chemistry transport model TM5 (Tracer Model 5, version TM5-chem-v3.0). A full description is given concerning the photochemical mechanism, the interaction with aerosol, the treatment of the stratosphere, the wet and dry deposition parameterizations, and the applied emissions. We e...

We present a simple method to perform degradation correction to Global Ozone Monitoring Experiment (GOME) reflectance spectra by comparing the average reflectance for 60 N–60 S with that at the beginning of GOME observations (July–December 1995) after removing the dependences on solar zenith angle and seasonal variation. The results indicate positive biases of up to ∼15–25% in the wavelength ra...

[1] Global Ozone Monitoring Experiment (GOME) observations from 1997–2000 have revealed the Tibetan Middle Tropospheric Ozone Minimum (TMTOM), a lowozone layer that occurs in the middle troposphere over the Tibetan Plateau (TP) in June. Ozone profiles were derived from GOME observations and validated by ozonesonde measurements at two stations (Lhasa and Xining) over the TP. The mean bias is 5–1...

Background The new observations of the tropospheric distributions of trace gases such as NO2 (nitrogen dioxide), SO2 (sulphur dioxide), HCHO (formaldehyde), BrO (bromine monoxide) and O3 (ozone), retrieved from GOME (Global Ozone Monitoring Experiment) measurements, herald the opening of a new era for tropospheric production, as a result of agricultural activities, and above all by vehicles suc...