0000000000378396
AUTHOR
Michaël Sicard
Aerosol closure study by lidar, sun photometry, and airborne optical counters during DAMOCLES field campaign at El Arenosillo sounding station, Spain
We present a comparison of aerosol properties derived from in situ and remote sensing instruments during DAMOCLES campaign, aimed at investigating the equivalence between the instrumentation and methodologies employed by several Spanish groups to study atmospheric aerosols at a regional background site. The complete set of instruments available during this closure experiment allowed collecting a valuable high-resolution aerosol measurement data set. The data set was augmented with airborne in situ measurements carried out in order to characterize aerosol particles during the midday of 29 June 2006. This work is focused on aerosol measurements using different techniques of high-quality instr…
Climatology of the aerosol extinction-to-backscatter ratio from sun-photometric measurements
The elastic lidar equation contains two unknown atmospheric parameters, namely, the particulate optical extinction and backscatter coefficients, which are related through the lidar ratio (i.e., the particulate-extinction-to-backscatter ratio). So far, independent inversion of the lidar signal has been carried out by means of Raman lidars (usually limited to nighttime measurements), high-spectral-resolution lidars, or scanning elastic lidars under the assumption of a homogeneously vertically stratified atmosphere. In this paper, we present a procedure to obtain the lidar ratio at 532 nm by a combined Sunphotometer– aerosol-model inversion, where the viability of the solution is largely reinf…
EARLINET observations of the 14-22-may long-range dust transport event during SAMUM 2006: validation of results from dust transport modelling
We observed a long-range transport event of mineral dust from North Africa to South Europe during the Saharan Mineral Dust Experiment (SAMUM) 2006. Geometrical and optical properties of that dust plume were determined with Sun photometer of the Aerosol Robotic Network (AERONET) and Raman lidar near the North African source region, and with Sun photometers of AERONET and lidars of the European Aerosol Research Lidar Network (EARLINET) in the far field in Europe. Extinction-to-backscatter ratios of the dust plume over Morocco and Southern Europe do not differ. Ångstr¨om exponents increase with distance from Morocco. We simulated the transport, and geometrical and optical properties of the dus…
Aerosol Lidar Intercomparison in the Framework of SPALINET—The Spanish Lidar Network: Methodology and Results
Abstract—A group of eight Spanish lidars was formed in order to extend the European Aerosol Research Lidar Network–Advanced Sustainable Observation System (EARLINET-ASOS)project. This study presents intercomparisons at the hardware and software levels. Results of the system intercomparisons are based on range-square-corrected signals in cases where the lidars viewed the same atmospheres. Comparisons were also made for aeros backscatter coefficients at 1064 nm (2 systems) and 532 nm (all systems), and for extinction coefficients at 532 nm (2 systems). In total, three field campaigns were carried out between 2006 and 2007. Comparisons were limited to the highest layer found before the free tr…
February 2017 extreme Saharan dust outbreak in the Iberian Peninsula: from lidar-derived optical properties to evaluation of forecast models
Abstract. An unprecedented extreme Saharan dust event was registered in winter time from 20 to 23 February 2017 over the Iberian Peninsula (IP). We report on aerosol optical properties observed under this extreme dust outbreak through remote sensing (active and passive) techniques. For that, EARLINET (European Aerosol Research LIdar NETwork) lidar and AERONET (AErosol RObotic NETwork) Sun-photometer Cimel CE 318 measurements are used. The sites considered are: Barcelona (41.38º N, 2.17º E), Burjassot (39.51º N, 0.42º W), Cabo da Roca (38.78º N, 9.50º W), Évora (38.57º N, 7.91º W), Granada (37.16º N, 3.61º W) and Madrid (40.45º N, 3.72º W). In general, large aerosol optical depths (AOD) and …
Daytime aerosol extinction profiles from the combination of CALIOP profiles and AERONET products
Abstract. The solar background illumination has a strong effect on CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) measurements, leading to a decrease in the signal-to-noise ratio of the lidar signal. Because of this, CALIOP level 2 data algorithms might be limited in the retrieval of the properties of the aerosols in the atmosphere. In this work, we present a methodology that combines CALIOP level 1 data with AERONET (Aerosol RObotic NETwork) measurements to retrieve aerosol extinction profiles and lidar ratios in daytime conditions. In this way, we fulfill a two-fold objective: first, we obtain more accurate daytime aerosol information; second, we supplement column integrated me…
Overview: On the transport and transformation of pollutants in the outflow of major population centres - Observational data from the EMeRGe European intensive operational period in summer 2017
Megacities and other major population centres (MPCs) worldwide are major sources of air pollution, both locally as well as downwind. The overall assessment and prediction of the impact of MPC pollution on tropospheric chemistry are challenging. The present work provides an overview of the highlights of a major new contribution to the understanding of this issue based on the data and analysis of the EMeRGe (Effect of Megacities on the transport and transformation of pollutants on the Regional to Global scales) international project. EMeRGe focuses on atmospheric chemistry, dynamics, and transport of local and regional pollution originating in MPCs. Airborne measurements, taking advantage of …
Extreme, wintertime Saharan dust intrusion in the Iberian Peninsula: Lidar monitoring and evaluation of dust forecast models during the February 2017 event
The research leading to these results has received funding from the H2020 program from the European Union (grant agreement no. 654109, 778349) and also from the Spanish Ministry of Industry, Economy and Competitiviness (MINECO, ref. CGL2013-45410-R, CGL2016-81092-R, CGL2017-85344-R, TEC2015-63832-P), the Spanish Ministry of Science, Innovation and Universities (ref. CGL2017-90884-REDT); the CommSensLab "Maria de Maeztu" Unity of Excellence (ref. MDM-2016-0600) financed by the Spanish Agencia Estatal de Investigación. Co-funding was also provided by the European Union through the European Regional Development Fund (ref. POCI-01-0145-FEDER-007690, ALT20-03-0145-FEDER-000004, ALT20-03-0145-FED…
Study of the correlation between columnar aerosol burden, suspended matter at ground and chemical components in a background European environment
Although routinely monitored by ground based air quality networks, the particulate matter distribution could be eventually better described with remote sensing techniques. However, valid relationships between ground level and columnar ground based quantities should be known beforehand. In this study we have performed a comparison between particulate matter measurements at ground level at different cut sizes (10, 2.5 and 1.0 mm), and the aerosol optical depth obtained by means of a ground based sunphotometer during a multiinstrumental field campaign held in El Arenosillo (Huelva, Spain) from 28 June to 4 July 2006. All the PM fractions were very well correlated with AOD with correlation coef…