Estimating bias in the OCO-2 retrieval algorithm caused by 3-D radiation scattering from unresolved boundary layer clouds
Atmos. Meas. Tech., 8, 1641-1656, doi:10.5194/amt-8-1641-2015, 2015
ALADINA – an unmanned research aircraft for observing vertical and horizontal distributions of ultrafine particles within the atmospheric boundary layer
Summary: The unmanned research aircraft Carolo P360 "ALADINA" is a flexible tool for investigating the horizontal and vertical distribution of freshly formed particles in the atmospheric boundary layer (ABL) combined with measurements of turbulent fluxes derived by fast meteorological sensors. First results of a feasibility study show, among others, events of particle bursts in an internal layer of the ABL. Comparisons with ground-based instruments and a lidar present the reliability of the new system.
Atmos. Meas. Tech., 8, 1627-1639, doi:10.5194/amt-8-1627-2015, 2015
Performance of WVSS-II hygrometers on the FAAM research aircraft
Summary: Comparisons on the FAAM BAe 146-301 aircraft show good agreement between chilled mirror hygrometers and a WVSS-II fed from a modified Rosemount inlet (wvssR) in coud-free conditions, but a WVSS-II fed from the standard flush inlet (wvssF) over-reads, except at higher humidities. Case studies in cloudy conditions show that wvssF is immune to liquid water and ice, whilst wvssR is susceptible to both. Both WVSS-II inlets respond much more rapidly than the chilled mirror devices, especially wvssF.
Atmos. Meas. Tech., 8, 1617-1625, doi:10.5194/amt-8-1617-2015, 2015
Meso-scale modelling and radiative transfer simulations of a snowfall event over France at microwaves for passive and active modes and evaluation with satellite observations
Atmos. Meas. Tech., 8, 1605-1616, doi:10.5194/amt-8-1605-2015, 2015
The impact of the microphysical properties of aerosol on the atmospheric correction of hyperspectral data in coastal waters
Atmos. Meas. Tech., 8, 1593-1604, doi:10.5194/amt-8-1593-2015, 2015
Towards validation of ammonia (NH3) measurements from the IASI satellite
Summary: In this study, comprehensive ground-based data sets (Europe, China, Africa and United States) are used to evaluate NH3 measurements from IASI. Global yearly and regional monthly comparisons show fair agreement, while hourly measurements are used to investigate the limitations of direct comparisons. In addition, dense airborne measurements are explored and show the highest correlation coefficients in this study. Finally, the urgent need for independent NH3 column measurements is discussed.
Atmos. Meas. Tech., 8, 1575-1591, doi:10.5194/amt-8-1575-2015, 2015
Using XCO2 retrievals for assessing the long-term consistency of NDACC/FTIR data sets
Atmos. Meas. Tech., 8, 1555-1573, doi:10.5194/amt-8-1555-2015, 2015
Cloud thermodynamic phase detection with polarimetrically sensitive passive sky radiometers
Summary: We test if ground-based sun photometers/radiometers like those in the Aerosol Robotic Network (AERONET) can use the polarization sensitivity of some instruments for improved cloud optical property retrieval. Our radiative transfer simulations show that the direction of linear polarization indicates cloud thermodynamic phase for optically thin clouds. In practice, data analysis shows a weak response with AERONET instruments, most likely due to noise and orientation/calibration ambiguity.
Atmos. Meas. Tech., 8, 1537-1554, doi:10.5194/amt-8-1537-2015, 2015
An improved retrieval of tropospheric NO2 from space over polluted regions using an Earth radiance reference
Summary: A new offline technique for retrieving tropospheric NO2 slant columns from space over urban regions is proposed in this work. An Earth radiance reference measurement from a remote unpolluted region is used instead of the standard solar irradiance measurement used by operational retrieval algorithms. Testing with spectra measured by the Ozone Monitoring Instrument (OMI) shows that the technique largely removes the presence of stratospheric NO2 and also greatly suppresses instrumental biases.
Atmos. Meas. Tech., 8, 1519-1535, doi:10.5194/amt-8-1519-2015, 2015
A comprehensive observational filter for satellite infrared limb sounding of gravity waves
Atmos. Meas. Tech., 8, 1491-1517, doi:10.5194/amt-8-1491-2015, 2015
Investigating bias in the application of curve fitting programs to atmospheric time series
Atmos. Meas. Tech., 8, 1469-1489, doi:10.5194/amt-8-1469-2015, 2015
Corrigendum to "Next-generation angular distribution models for top-of-atmosphere radiative flux calculation from CERES instruments: methodology" published in Atmos. Meas. Tech., 8, 611–632, 2015
Atmos. Meas. Tech., 8, 1467-1467, doi:10.5194/amt-8-1467-2015, 2015
Cross-validation of IASI/MetOp derived tropospheric δD with TES and ground-based FTIR observations
Summary: This paper describes a cross-validation study of tropospheric δD (HDO/H2O ratio) profiles retrieved from IASI spectra (retrieval performed at ULB). We document how these profiles compare to profiles derived from TES/AURA sounder and from three ground-based FTIRs of the NDACC network (produced within the MUSICA project). We show that empirical differences are in agreement with the theoretical expected differences which are dominated by IASI observational and the smoothing error components.
Atmos. Meas. Tech., 8, 1447-1466, doi:10.5194/amt-8-1447-2015, 2015
Water vapor observations up to the lower stratosphere through the Raman lidar during the Maïdo Lidar Calibration Campaign
Atmos. Meas. Tech., 8, 1425-1445, doi:10.5194/amt-8-1425-2015, 2015
Infrared and millimetre-wave scintillometry in the suburban environment – Part 2: Large-area sensible and latent heat fluxes
Summary: Two-wavelength scintillometry, a ground-based remote sensing technique for deriving large-area heat fluxes, has been used over an urban area for the first time. The long data set enables investigation of the performance of the technique and characteristics of turbulent transport processes at sub-daily to inter-annual timescales. In this second paper, sensible and latent heat fluxes representative of an area of 5--10 km2 are presented and analysed.
Atmos. Meas. Tech., 8, 1407-1424, doi:10.5194/amt-8-1407-2015, 2015
Infrared and millimetre-wave scintillometry in the suburban environment – Part 1: Structure parameters
Summary: Two-wavelength scintillometry, a ground-based remote sensing technique for deriving large-area heat fluxes, has been used over an urban area for the first time. The long data set enables investigation of the performance of the technique and characteristics of turbulent transport processes at sub-daily to inter-annual timescales. In this first paper, the structure parameters of temperature and humidity, and the correlation between temperature and humidity, are presented and analysed.
Atmos. Meas. Tech., 8, 1385-1405, doi:10.5194/amt-8-1385-2015, 2015
A spectral method for discriminating thermodynamic phase and retrieving cloud optical thickness and effective radius using transmitted solar radiance spectra
Summary: Cloud properties are obtained via transmitted light that has interacted with cloud particles throughout its vertical extent. To achieve this, we introduce a new retrieval based on spectrally resolved measurements. We used 15 parameters to quantify spectral features in transmitted light modulated by cloud optical thickness, effective radius, and thermodynamic phase. When applied to ground-based measurements, this method results in a closer match to measured spectra than two other methods.
Atmos. Meas. Tech., 8, 1361-1383, doi:10.5194/amt-8-1361-2015, 2015
A novel inlet system for online chemical analysis of semi-volatile submicron particulate matter
Atmos. Meas. Tech., 8, 1353-1360, doi:10.5194/amt-8-1353-2015, 2015
Potential of the TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor for the monitoring of terrestrial chlorophyll fluorescence
Summary: This paper investigates the potential of the upcoming TROPOspheric Monitoring Instrument (TROPOMI) instrument for the retrieval of the chlorophyll fluorescence signal emitted in the 650–850nm spectral range by the photosynthetic machinery of green plants. We find that TROPOMI will allow substantial improvements in the space monitoring of fluorescence with respect to current spaceborne instruments such as GOME-2 and SCIAMACHY.
Atmos. Meas. Tech., 8, 1337-1352, doi:10.5194/amt-8-1337-2015, 2015
Cross-track Infrared Sounder (CrIS) satellite observations of tropospheric ammonia
Summary: Presented is a robust retrieval algorithm that demonstrates the capabilities of utilizing Cross-track Infrared Sounder (CrIS) satellite observations to globally retrieval ammonia (NH3) concentrations. Initial NH3 retrieval results show that CrIS is (i) sensitive to NH3 in the boundary layer, with peak vertical sensitivity typically around 850–750hPa (~2km), (ii) has a minimum detection limit of ~1ppbv (peak profile value typically at the surface), and (iii) typically has up to ~1 DOFS.
Atmos. Meas. Tech., 8, 1323-1336, doi:10.5194/amt-8-1323-2015, 2015