SPARTAN: a global network to evaluate and enhance satellite-based estimates of ground-level particulate matter for global health applications
Summary: We have initiated a global network of ground-level monitoring stations to measure concentrations of fine aerosols in urban environments. Our findings include major ions species, total mass, and total scatter at three wavelengths. Results will be used to further evaluate and enhance satellite remote sensing estimates.
G. Snider, C. L. Weagle, R. V. Martin, A. van Donkelaar, K. Conrad, D. Cunningham, C. Gordon, M. Zwicker, C. Akoshile, P. Artaxo, N. X. Anh, J. Brook, J. Dong, R. M. Garland, R. Greenwald, D. Griffith, K. He, B. N. Holben, R. Kahn, I. Koren, N. Lagrosas, P. Lestari, Z. Ma, J. Vanderlei Martins, E. J. Quel, Y. Rudich, A. Salam, S. N. Tripathi, C. Yu, Q. Zhang, Y. Zhang, M. Brauer, A. Cohen, M. D. Gibson, and Y. Liu Atmos. Meas. Tech., 8, 505-521, 2015 AbstractFinal Revised Paper (PDF, 2230 KB)Discussion Paper (AMTD)
30 Jan 2015
Empirical validation and proof of added value of MUSICA's tropospheric δD remote sensing products
M. Schneider, Y. González, C. Dyroff, E. Christner, A. Wiegele, S. Barthlott, O. E. García, E. Sepúlveda, F. Hase, J. Andrey, T. Blumenstock, C. Guirado, R. Ramos, and S. Rodríguez Atmos. Meas. Tech., 8, 483-503, 2015 AbstractFinal Revised Paper (PDF, 2703 KB)Discussion Paper (AMTD)
30 Jan 2015
A semi-automated system for quantifying the oxidative potential of ambient particles in aqueous extracts using the dithiothreitol (DTT) assay: results from the Southeastern Center for Air Pollution and Epidemiology (SCAPE)
Summary: This work summarizes a newly developed semi-automated system for quantifying the oxidative potential of aerosol aqueous extracts using the dithiothreitol (DTT) assay. 500 sample analyses indicate that DTT activity in the southeast US is likely not dominated by a unique local source, and sources change with season. The unique large data set generated with the technique described in this paper allows new studies on DTT sources and investigating linkages between reactive oxygen species and health.
Distinguishing cirrus cloud presence in autonomous lidar measurements
Summary: Digital thresholds based on 2012 CALIOP satellite lidar measurements are investigated for distinguishing cirrus cloud presence, including cloud top temperatures and heights combined with layer depolarization and phase and optical depths. A cloud top temperature of -37 C is found to exhibit the most stable performance, owing to it being the point of homogeneous liquid-water freezing. Depolarization and phase help but are mostly ambiguous at warmer temperatures where mixed-phase clouds propagate.
The Midlatitude Continental Convective Clouds Experiment (MC3E) sounding network: operations, processing and analysis
Summary: A major component of the 2011 Midlatitude Continental Convective Clouds Experiment (MC3E) was a six-site radiosonde array designed to capture the large-scale variability of the atmospheric state. This manuscript describes the details of the MC3E radiosonde operations including the instrumentation, data processing and analysis of the impacts of bias correction and algorithm assumptions on the determination of forcing data sets.
Tropospheric ozone and ozone profiles retrieved from GOME-2 and their validation
Summary: This work provides a description and validation of significantly updated algorithm for the retrieval of atmospheric ozone profiles, with a focus on the sensitivity to ozone in the lower troposphere. The satellite-derived ozone profiles are validated against ozonesondes globally, and achieves an average bias of 6% in the lower troposphere. The global distribution is also compared to the ozone distribution from a chemistry transport model, with an average agreement of less than 2 Dobson units.
Adaptive neuro-fuzzy inference system for temperature and humidity profile retrieval from microwave radiometer observations
Summary: The study of atmospheric convection is important for the understanding of evolution of diurnal cycles of rainfall. High-resolution observations of vertical profiles of temperature and relative humidity are very useful for understanding the behaviour of these convections. Microwave radiometers are becoming useful tools for it. In this paper, we propose a new method to retrieve these profiles based on adaptive neuro-fuzzy interface systems and find that this method has a better skill of retrieval.
Corrigendum to "Comparison between CARIBIC Aerosol Samples Analysed by Accelerator-Based Methods and Optical Particle Counter Measurements" published in Atmos. Meas. Tech., 7, 2581–2596, 2014
B. G. Martinsson, J. Friberg, S. M. Andersson, A. Weigelt, M. Hermann, D. Assmann, J. Voigtländer, C. A. M. Brenninkmeijer, P. J. F. van Velthoven, and A. Zahn Atmos. Meas. Tech., 8, 367-367, 2015 AbstractFinal Revised Paper (PDF, 19 KB)Corresponding Article
22 Jan 2015
Correction of raindrop size distributions measured by Parsivel disdrometers, using a two-dimensional video disdrometer as a reference
Summary: Using the 2-D video disdrometer (2DVD) as a reference, a technique to correct the spectra of drop size distribution (DSD) measured by Parsivel disdrometers (1st and 2nd generation) is proposed. The measured velocities and equivolume diameters are corrected to better match those from the 2DVD. The correction is evaluated using data from southern France and the Swiss Plateau. It appears to be similar for both climatologies, and to improve the consistency with colocated 2DVDs and rain gauges.
Fiber optic distributed temperature sensing for the determination of air temperature
Summary: By using two cylindrical thermometers with different diameters, one can determine what temperature a zero diameter thermometer would have. Such a virtual thermometer would not be affected by solar heating and would take on the temperature of the surrounding air. We applied this principle to atmospheric temperature measurements with fiber optic cables using distributed temperature sensing (DTS). With two unshielded cable pairs, one black pair and one white pair, good results were obtained.
Forecast indices from a ground-based microwave radiometer for operational meteorology
Summary: Forecast indices commonly used in operational meteorology can be computed from temperature and humidity profiles retrieved from a ground-based microwave radiometer.
The values of radiometer-derived forecast indices agree well with values computed from radiosondes (correlation usually above 0.8).
Radiometer-derived forecast indices offer the advantage (with respect to radiosondes) of nearly continuous data, capturing the entire diurnal cycle and providing fresh and timely data to forecasters.
The Orbiting Carbon Observatory (OCO-2): spectrometer performance evaluation using pre-launch direct sun measurements
C. Frankenberg, R. Pollock, R. A. M. Lee, R. Rosenberg, J.-F. Blavier, D. Crisp, C. W. O'Dell, G. B. Osterman, C. Roehl, P. O. Wennberg, and D. Wunch Atmos. Meas. Tech., 8, 301-313, 2015 AbstractFinal Revised Paper (PDF, 7296 KB)Discussion Paper (AMTD)
14 Jan 2015
Use of neural networks in ground-based aerosol retrievals from multi-angle spectropolarimetric observations
Summary: A neural network algorithm has been developed to retrieve aerosol microphysical parameters from ground-based measurements of skylight intensity and polarization. The neural network is capable of producing accurate estimates of aerosol optical thicknesses, effective radii and refractive index. In addition, it is shown that the use of the neural retrievals as initial guess for an iterative retrieval algorithm results in improved convergence and retrieval accuracy.
A. Di Noia, O. P. Hasekamp, G. van Harten, J. H. H. Rietjens, J. M. Smit, F. Snik, J. S. Henzing, J. de Boer, C. U. Keller, and H. Volten Atmos. Meas. Tech., 8, 281-299, 2015 AbstractFinal Revised Paper (PDF, 4168 KB)Discussion Paper (AMTD)
14 Jan 2015
Development and validation of inexpensive, automated, dynamic flux chambers