H2S interference on CO2 isotopic measurements using a Picarro G1101-i cavity ring-down spectrometer
Summary: Portable cavity ring-down spectrometers (e.g. G1101-i) for isotopic CO2 have an interference with elevated (higher than ambient) amounts of hydrogen sulfide (H2S). This results from the overlap of the H2S and CO2 spectral lines in the near-infrared, causing changes in both the 12CO2 and 13CO2 concentrations. This effect can be removed by reacting H2S with a metal scrub before analysis, which will facilitate the application of these instruments in H2S-rich environments (i.e. active volcanoes).
Atmos. Meas. Tech., 8, 4075-4082, doi:10.5194/amt-8-4075-2015, 2015
Development and characterisation of a state-of-the-art GOME-2 formaldehyde air-mass factor algorithm
Summary: This work presents the air mass factor (AMF) algorithm in use at the University of Leicester, which introduces scene-specific variables into a per-observation full radiative transfer AMF calculation, including increasing spatial resolution of key environmental parameter databases, input variable area weighting, instrument-specific scattering weight calculation, and inclusion of an ozone vertical profile climatology.
Atmos. Meas. Tech., 8, 4055-4074, doi:10.5194/amt-8-4055-2015, 2015
Altitude misestimation caused by the Vaisala RS80 pressure bias and its impact on meteorological profiles
Summary: For conventional soundings, the pressure bias of radiosonde leads to an altitude misestimation, which can lead to offsets in any meteorological profile. Therefore, we must take this issue into account to improve historical data sets.
Atmos. Meas. Tech., 8, 4043-4054, doi:10.5194/amt-8-4043-2015, 2015
Uncertainties of satellite-derived surface skin temperatures in the polar oceans: MODIS, AIRS/AMSU, and AIRS only
Summary: Uncertainties in the satellite-derived surface skin temperature (SST) data in the polar oceans during two periods (Apr. 16-24, Sep. 15-23) of 2003-2014 were investigated and the following three data sets were intercompared: MODIS IST, the SST of AIRS/AMSU-A and AIRS only. There was a systematic disagreement between the three data sets at the boundary of the sea ice possibly due to the surface classification method. The temperature disagreement had an impact on the resulting temperature trends.
Atmos. Meas. Tech., 8, 4025-4041, doi:10.5194/amt-8-4025-2015, 2015
Predicting ambient aerosol thermal–optical reflectance measurements from infrared spectra: elemental carbon
Summary: Elemental carbon (EC), a constituent of atmospheric particulate matter (PM), adversely affects climate, visibility and human health. EC is measured in PM monitoring networks world-wide but the method is expensive and destructive to the samples. Here, methods are presented to accurately predict EC using Fourier transform infrared (FT-IR) analysis which is inexpensive and non-destructive. This method complements measurements of organic carbon and organic functional groups made using FT-IR.
Atmos. Meas. Tech., 8, 4013-4023, doi:10.5194/amt-8-4013-2015, 2015
Bisulfate – cluster based atmospheric pressure chemical ionization mass spectrometer for high-sensitivity (< 100 ppqV) detection of atmospheric dimethyl amine: proof-of-concept and first ambient data from boreal forest
Summary: Atmospheric concentrations of amines are poorly known mainly due to challenges related to their reliable high-sensitivity detection. We have created a method and instrument that is capable for detecting amines with lowest limit of detection of around 0.01 parts per trillion. Application of the instrument in the field study indicates that concentrations of dimethyl amine in a boreal forest site are below 0.03ppt, not enough to account for the observed new particle formation rates.
Atmos. Meas. Tech., 8, 4001-4011, doi:10.5194/amt-8-4001-2015, 2015
Fuzzy logic filtering of radar reflectivity to remove non-meteorological echoes using dual polarization radar moments
Summary: This paper describes a radar echo classification scheme, used to identify and remove non-meteorlogical echoes from X-band radar data. The classifier uses fuzzy logic to incorporate multiple radar moments, including linear texture fields, into the decision scheme. The scheme is trained on a limited subset of data from a short field deployment. The feasibility of the scheme is then demonstrated with a range of examples from two field deployments in the UK.
Atmos. Meas. Tech., 8, 3985-4000, doi:10.5194/amt-8-3985-2015, 2015
Correction of water vapor absorption for aerosol remote sensing with ceilometers
Summary: For the past few years a large number of autonomous continuously operating single-wavelength backscatter lidars, so called ceilometers, have been installed. Currently the assessment of their potential for aerosol remote sensing is a major research topic. This paper focusses on the need to consider water vapor absorption if ceilometers emitting at wavelengths in the 905 to 910 nm range are used and proposes a correction scheme to improve the retrieval of the aerosol backscatter coefficient.
Atmos. Meas. Tech., 8, 3971-3984, doi:10.5194/amt-8-3971-2015, 2015
Characterizing black carbon in rain and ice cores using coupled tangential flow filtration and transmission electron microscopy
Summary: Black carbon is an important environmental pollutant, and the structure and composition of these particles are important to measuring their affect on the climate. Historical records of black carbon emissions are stored in polar ice. This paper details a new method to study black carbon preserved in Antarctic ice cores. By combining filtration to concentrate the particles and electron microscopy to characterize them, this method opens up a new avenue to study the history of our atmosphere.
Atmos. Meas. Tech., 8, 3959-3969, doi:10.5194/amt-8-3959-2015, 2015
Three years of semicontinuous greenhouse gas measurements at the Puy de Dôme station (central France)
Atmos. Meas. Tech., 8, 3941-3958, doi:10.5194/amt-8-3941-2015, 2015
The GOME-type Total Ozone Essential Climate Variable (GTO-ECV) data record from the ESA Climate Change Initiative
Atmos. Meas. Tech., 8, 3923-3940, doi:10.5194/amt-8-3923-2015, 2015
PTRwid: A new widget tool for processing PTR-TOF-MS data
Atmos. Meas. Tech., 8, 3903-3922, doi:10.5194/amt-8-3903-2015, 2015
A novel approach for the extraction of cloud motion vectors using airglow imager measurements
Atmos. Meas. Tech., 8, 3893-3901, doi:10.5194/amt-8-3893-2015, 2015
Comprehensive laboratory and field testing of cavity ring-down spectroscopy analyzers measuring H2O, CO2, CH4 and CO
Summary: We present the results of tests of CRDS instruments in the laboratory (47 instruments) and in the field (15 instruments). We demonstrate that, thanks to rigorous testing, newer models generally perform better than older models, especially in terms of reproducibility between instruments. In the field, we see the importance of individual diagnostics during the installation phase, and we show the value of calibration and target gases that assess the quality of the data.
Atmos. Meas. Tech., 8, 3867-3892, doi:10.5194/amt-8-3867-2015, 2015
Intercomparison of two comparative reactivity method instruments inf the Mediterranean basin during summer 2013
Summary: Our manuscript shows results of an intercomparison exercise conducted on two home-built comparative reactivity method (CRM) instruments operating under the same settings for measuring total OH reactivity. Despite the corrections of the raw data sets for instrumental artifacts having different weights on the two CRMs, we found very consistent results for the final processed data of ambient OH reactivity. Furthermore, we present in detail how to validate the instruments and process the raw data.
Atmos. Meas. Tech., 8, 3851-3865, doi:10.5194/amt-8-3851-2015, 2015
OMI tropospheric NO2 air mass factors over South America: effects of biomass burning aerosols
Summary: Inaccuracies in the retrieval of NO2 tropospheric columns due to the radiative effects of light-absorbing aerosols are not well understood. Here we explicitly account for the effects of aerosols in the Dutch OMI NO2 (DOMINO) tropospheric AMF calculation by including aerosol observations collocated with OMI pixels. The AMF calculations that included aerosol absorption and scattering were on average 10% higher than traditional AMFs. Errors can reach a factor of 2 for individual pixels.
Atmos. Meas. Tech., 8, 3831-3849, doi:10.5194/amt-8-3831-2015, 2015
Aerosol mass spectrometry: particle–vaporizer interactions and their consequences for the measurements
Atmos. Meas. Tech., 8, 3811-3830, doi:10.5194/amt-8-3811-2015, 2015
Synchronous polar winter starphotometry and lidar measurements at a High Arctic station
Atmos. Meas. Tech., 8, 3789-3809, doi:10.5194/amt-8-3789-2015, 2015
The impact of vibrational Raman scattering of air on DOAS measurements of atmospheric trace gases
Summary: In remote sensing applications, such as differential optical absorption spectroscopy (DOAS), atmospheric scattering processes need to be considered. Inelastic scattering on air molecules can lead to filling-in of absorption lines. The contribution of rotational Raman scattering is typically corrected for. The magnitude of vibrational Raman scattering (VRS) is known from theory and agrees with our first DOAS observations of this effect. Its impact on trace-gas measurements of NO2 is discussed.
Atmos. Meas. Tech., 8, 3767-3787, doi:10.5194/amt-8-3767-2015, 2015
Determining air pollutant emission rates based on mass balance using airborne measurement data over the Alberta oil sands operations
Summary: Aircraft-based measurements of air pollutants from sources in the Canadian oil sands were made during a summer intensive field campaign in 2013. This paper describes the top-down emission rate retrieval algorithm (TERRA) to determine facility emissions of pollutants, using SO2 and CH4 as examples. Uncertainty of the emission rates estimated with TERRA is estimated as less than 30%, which is primarily due to the unknown SO2 and CH4 mixing ratios near the surface below the lowest flight level.
Atmos. Meas. Tech., 8, 3745-3765, doi:10.5194/amt-8-3745-2015, 2015