scholarly journals Intercomparison of aerosol measurements performed with multi-wavelength Raman lidars, automatic lidars and ceilometers in the framework of INTERACT-II campaign

2018 ◽  
Vol 11 (4) ◽  
pp. 2459-2475 ◽  
Author(s):  
Fabio Madonna ◽  
Marco Rosoldi ◽  
Simone Lolli ◽  
Francesco Amato ◽  
Joshua Vande Hey ◽  
...  
Keyword(s):  
Laser Pulses ◽  
Raman Lidar ◽  
Calibration Constant ◽  
Normalization Constant ◽  
Fractional Difference ◽  
Seasonal Behavior ◽  
Lidar Measurements ◽  
Multi Wavelength ◽  
Micro Pulse Lidar ◽  
Cloud Tracking

Abstract. Following the previous efforts of INTERACT (INTERcomparison of Aerosol and Cloud Tracking), the INTERACT-II campaign used multi-wavelength Raman lidar measurements to assess the performance of an automatic compact micro-pulse lidar (MiniMPL) and two ceilometers (CL51 and CS135) in providing reliable information about optical and geometric atmospheric aerosol properties. The campaign took place at the CNR-IMAA Atmospheric Observatory (760 ma.s.l.; 40.60∘ N, 15.72∘ E) in the framework of ACTRIS-2 (Aerosol Clouds Trace gases Research InfraStructure) H2020 project. Co-located simultaneous measurements involving a MiniMPL, two ceilometers and two EARLINET multi-wavelength Raman lidars were performed from July to December 2016. The intercomparison highlighted that the MiniMPL range-corrected signals (RCSs) show, on average, a fractional difference with respect to those of CNR-IMAA Atmospheric Observatory (CIAO) lidars ranging from 5 to 15 % below 2.0 km a.s.l. (above sea level), largely due to the use of an inaccurate overlap correction, and smaller than 5 % in the free troposphere. For the CL51, the attenuated backscatter values have an average fractional difference with respect to CIAO lidars < 20–30 % below 3 km and larger above. The variability of the CL51 calibration constant is within ±46 %. For the CS135, the performance is similar to the CL51 below 2.0 kma.s.l., while in the region above 3 kma.s.l. the differences are about ±40 %. The variability of the CS135 normalization constant is within ±47 %. Finally, additional tests performed during the campaign using the CHM15k ceilometer operated at CIAO showed the clear need to investigate the CHM15k historical dataset (2010–2016) to evaluate potential effects of ceilometer laser fluctuations on calibration stability. The number of laser pulses shows an average variability of 10 % with respect to the nominal power which conforms to the ceilometer specifications. Nevertheless, laser pulses variability follows seasonal behavior with an increase in the number of laser pulses in summer and a decrease in winter. This contributes to explain the dependency of the ceilometer calibration constant on the environmental temperature hypothesized during INTERACT.

scholarly journals Intercomparison of aerosol measurements performed with multi-wavelength Raman lidars, automatic lidars and ceilometers in the frame of INTERACT-II campaign

2017 ◽  
Author(s):  
Fabio Madonna ◽  
Marco Rosoldi ◽  
Simone Lolli ◽  
Francesco Amato ◽  
Joshua Vande Hey ◽  
...  
Keyword(s):  
Atmospheric Aerosol ◽  
Trace Gases ◽  
Average Difference ◽  
Raman Lidar ◽  
Simultaneous Measurements ◽  
Lidar Measurements ◽  
Multi Wavelength ◽  
Micro Pulse Lidar ◽  
Aerosol Properties ◽  
Cloud Tracking

Abstract. Following on from the previous efforts of INTERACT (INTERcomparison of Aerosol and Cloud Tracking), the INTERACT-II campaign used multi-wavelength Raman lidar measurements to assess the performance of an automatic compact micro-pulse lidar (MiniMPL) and two ceilometers (CL51 and CS135), respectively, to provide reliable information about optical and geometric atmospheric aerosol properties. The campaign took place at the CNR-IMAA Atmospheric Observatory (760 m asl, 40.60° N, 15.72° E), in the framework of the ACTRIS-2 (Aerosol Clouds Trace gases Research InfraStructure) H2020 project. Co-located simultaneous measurements involving a MiniMPL, two ceilometers, and two EARLINET multi-wavelength Raman lidars (MUSA and PEARL) were performed from July to December 2016. Range-corrected signals (RCS) of MiniMPL showed an average difference with respect to MUSA/PEARL RCS of less than 10–15 % below 3.0 km above sea level, largely due to the use of an inaccurate overlap correction, and smaller than 5 % in the free troposphere. For the CL51, the average difference with respect to MUSA/PEARL attenuated backscatter is

scholarly journals Ceilometer aerosol profiling vs. Raman lidar in the frame of INTERACT campaign of ACTRIS

2014 ◽  
Vol 7 (12) ◽  
pp. 12407-12447 ◽  
Author(s):  
F. Madonna ◽  
F. Amato ◽  
J. Vande Hey ◽  
G. Pappalardo
Keyword(s):  
Atmospheric Aerosol ◽  
Correction Function ◽  
Cloud Base ◽  
Raman Lidar ◽  
Lidar Measurements ◽  
Multi Wavelength ◽  
Strong Motivation ◽  
Technological Improvements ◽  
First Time ◽  
Cloud Tracking

Abstract. Despite their differences from more advanced and more powerful lidars, the low construction and operation cost of ceilometers, originally designed for cloud base height monitoring, has fostered their use for the quantitative study of aerosol properties. The large number of ceilometers available worldwide represents a strong motivation to investigate both the extent to which they can be used to fill in the geographical gaps between advanced lidar stations and also how their continuous data flow can be linked to existing networks of the more advanced lidars, like EARLINET (European Aerosol Research LIdar NETwork). In this paper, multi-wavelength Raman lidar measurements are used to investigate the capability of ceilometers to provide reliable information about atmospheric aerosol content through the INTERACT (INTERcomparison of Aerosol and Cloud Tracking) campaign carried out at the CNR-IMAA Atmospheric Observatory (760 m a.s.l., 40.60° N, 15.72° E), in the framework of ACTRIS (Aerosol Clouds Trace gases Research InfraStructure) FP7 project. This work is the first time that three different commercial ceilometers with an advanced Raman lidar are compared over a period of six months. The comparison of the attenuated backscatter profiles from a multi-wavelength Raman lidar and three ceilometers (CHM15k, CS135s, CT25K) reveals differences due to the expected discrepancy in the SNR but also due to effect of changes in the ambient temperature on the short and mid-term stability of ceilometer calibration. A large instability of ceilometers in the incomplete overlap region has also been observed, making the use of a single overlap correction function for the whole duration of the campaign critical. Therefore, technological improvements of ceilometers towards their operational use in the monitoring of the atmospheric aerosol in the low and free troposphere are needed.

scholarly journals One year of CNR-IMAA multi-wavelength Raman lidar measurements in correspondence of CALIPSO overpass: Level 1 products comparison

2009 ◽  
Vol 9 (2) ◽  
pp. 8429-8468 ◽  
Author(s):  
L. Mona ◽  
G. Pappalardo ◽  
A. Amodeo ◽  
G. D'Amico ◽  
F. Madonna ◽  
...  
Keyword(s):  
Relative Difference ◽  
Raman Lidar ◽  
Continental Scale ◽  
Tropospheric Aerosol ◽  
Lidar Measurements ◽  
Multi Wavelength ◽  
The Mean ◽  
Level 1 ◽  
The Difference ◽  
Mean Differences

Abstract. At CNR-IMAA, an aerosol lidar system is operative since May 2000 in the framework of EARLINET (European Aerosol Research Lidar Network), the first lidar network for tropospheric aerosol study on continental scale. High quality multi-wavelength measurements make this system a reference point for the validation of data products provided by CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations), the first satellite-borne lidar specifically designed for aerosol and cloud study. Since 14 June 2006, devoted measurements are performed at CNR-IMAA in coincidence of CALIPSO overpasses. For the first time, results on 1-year comparisons between ground-based multi-wavelength Raman lidar measurements and corresponding CALIPSO lidar Level 1 profiles are presented. A methodology for the comparison is presented and discussed into details. Cases with the detection of cirrus clouds in CALIPSO data are separately analysed for taking into account eventual multiple scattering effects. For cirrus cloud cases, few cases are available to draw any conclusions. For clear sky conditions, the comparison shows good performances of the CALIPSO on-board lidar: the mean relative difference between the ground-based and CALIPSO Level 1 measurements is always within its standard deviation at all altitudes, with a mean difference in the 3–8 km altitude range of (−2±12)%. At altitude ranges corresponding to the typical PBL height observed at CNR-IMAA, a mean underestimation of (−24±20)% is observed in CALIPSO data, probably due to the difference in the aerosol content at the location of PEARL and CALIPSO ground-track location. Finally, the mean differences are on average lower for the closest overpasses (at about 40 km), with an increment of the differences at all altitude ranges when the 80 km overpasses are considered.

scholarly journals Estimate of rain evaporation rates from dual-wavelength lidar measurements: comparison against a model analytical solution

2018 ◽  
Vol 176 ◽  
pp. 04002
Author(s):  
Simone Lolli ◽  
Paolo Di Girolamo ◽  
Belay Demoz ◽  
Xiaowen Li ◽  
Ellsworth J. Welton
Keyword(s):  
Analytical Solution ◽  
Evaporation Rate ◽  
Dual Wavelength ◽  
Raman Lidar ◽  
Lidar Measurements ◽  
Median Volume ◽  
Multi Wavelength

Rain evaporation significantly contributes to moisture and heat cloud budgets. In this paper, we illustrate an approach to estimate the median volume raindrop diameter and the rain evaporation rate profiles from dual-wavelength lidar measurements. These observational results are compared with those provided by a model analytical solution. We made use of measurements from the multi-wavelength Raman lidar BASIL.

scholarly journals Ceilometer aerosol profiling versus Raman lidar in the frame of the INTERACT campaign of ACTRIS

2015 ◽  
Vol 8 (5) ◽  
pp. 2207-2223 ◽  
Author(s):  
F. Madonna ◽  
F. Amato ◽  
J. Vande Hey ◽  
G. Pappalardo
Keyword(s):  
Atmospheric Aerosols ◽  
Signal To Noise Ratio ◽  
Cloud Base ◽  
Raman Lidar ◽  
Backscatter Coefficient ◽  
Lidar Measurements ◽  
Multi Wavelength ◽  
Strong Motivation ◽  
Technological Improvements ◽  
Aerosol Properties

Abstract. Despite their differences from more advanced and more powerful lidars, the low construction and operation cost of ceilometers (originally designed for cloud base height monitoring) has fostered their use for the quantitative study of aerosol properties. The large number of ceilometers available worldwide represents a strong motivation to investigate both the extent to which they can be used to fill in the geographical gaps between advanced lidar stations and also how their continuous data flow can be linked to existing networks of the more advanced lidars, like EARLINET (European Aerosol Research Lidar Network). In this paper, multi-wavelength Raman lidar measurements are used to investigate the capability of ceilometers to provide reliable information about atmospheric aerosol properties through the INTERACT (INTERcomparison of Aerosol and Cloud Tracking) campaign carried out at the CNR-IMAA Atmospheric Observatory (760 m a.s.l., 40.60° N, 15.72° E), in the framework of the ACTRIS (Aerosol Clouds Trace gases Research InfraStructure) FP7 project. This work is the first time that three different commercial ceilometers with an advanced Raman lidar are compared over a period of 6 months. The comparison of the attenuated backscatter coefficient profiles from a multi-wavelength Raman lidar and three ceilometers (CHM15k, CS135s, CT25K) reveals differences due to the expected discrepancy in the signal to noise ratio (SNR) but also due to changes in the ambient temperature on the short and mid-term stability of ceilometer calibration. Therefore, technological improvements are needed to move ceilometers towards operational use in the monitoring of atmospheric aerosols in the low and free troposphere.

scholarly journals Technical Note: One year of Raman-lidar measurements in Gual Pahari EUCAARI site close to New Delhi in India – Seasonal characteristics of the aerosol vertical structure

2012 ◽  
Vol 12 (10) ◽  
pp. 4513-4524 ◽  
Author(s):  
M. Komppula ◽  
T. Mielonen ◽  
A. Arola ◽  
K. Korhonen ◽  
H. Lihavainen ◽  
...  
Keyword(s):  
Technical Note ◽  
New Delhi ◽  
Aerosol Layer ◽  
Raman Lidar ◽  
Extinction Coefficients ◽  
Seasonal Characteristics ◽  
Lidar Measurements ◽  
Multi Wavelength ◽  
Lidar Ratio ◽  
One Year

Abstract. One year of multi-wavelength (3 backscatter + 2 extinction + 1 depolarization) Raman lidar measurements at Gual Pahari, close to New Delhi, were analysed. The data was split into four seasons: spring (March–May), summer (June–August), autumn (September–November) and winter (December–February). The vertical profiles of backscatter, extinction, and lidar ratio and their variability during each season are presented. The measurements revealed that, on average, the aerosol layer was at its highest in spring (5.5 km). In summer, the vertically averaged (between 1–3 km) backscatter and extinction coefficients had the highest averages (3.3 Mm−1 sr−1 and 142 Mm−1 at 532 nm, respectively). Aerosol concentrations were slightly higher in summer compared to other seasons, and particles were larger in size. The autumn showed the highest lidar ratio and high extinction-related Ångström exponents (AEext), indicating the presence of smaller probably absorbing particles. The winter had the lowest backscatter and extinction coefficients, but AEext was the highest, suggesting still a large amount of small particles.

First comparisons between CNR-IMAA multi-wavelength Raman lidar measurements and CALIPSO measurements

2007 ◽  
Author(s):  
Lucia Mona ◽  
Aldo Amodeo ◽  
Giuseppe D'Amico ◽  
Gelsomina Pappalardo
Keyword(s):  
Raman Lidar ◽  
Lidar Measurements ◽  
Multi Wavelength

scholarly journals Characterization of Aerosol Size and Microphysical Properties from Multi-Wavelength Raman Lidar Measurements: Inter-Comparison with in Situ Sensors Onboard the ATR 42 in the Framework of HyMEX-SOP1

2020 ◽  
Vol 237 ◽  
pp. 02009
Author(s):  
Benedetto De Rosa ◽  
Paolo Di Girolamo ◽  
Donato Summa ◽  
Dario Stellitano
Keyword(s):  
Hydrological Cycle ◽  
Aerosol Layer ◽  
Raman Lidar ◽  
Microphysical Properties ◽  
Lidar Measurements ◽  
Retrieval Scheme ◽  
Research Aircraft ◽  
Multi Wavelength ◽  
In Situ Sensors

This extended abstract reports measurements that were carried out by the Raman lidar system BASIL in the frame of the Hydrological Cycle in the Mediterranean Experiment – Special Observation Period 1 (HyMeX-SOP1). A specific case study was selected revealing the presence of variable aerosol properties at different altitudes. Specifically, Raman lidar measurements on 02 October 2012 reveal the presence of two distinct aerosol layers, a lower one extending up to ~3 km and an upper one extending from 3.5 km to 4.7 km. Aerosol and size microphysical properties are determined from multi-wavelength measurements of particle backscattering and extinction profiles based on the application of a retrieval scheme which employs Tikhonov’s inversion with regularization. Inversion results suggest a size distribution with the presence, in both the lower and upper aerosol layer, of two particle modes (a fine mode, with a radius of ~0.2 μm, and a coarse mode, with radii in the range 2-4 μm), volume concentration values of 2-4 mm3cm-3 and effective radii in the range 0.2-0.6 μm. This effort benefited from the dedicated flights of the French research aircraft ATR42, equipped with a variety of in situ sensors for measuring aerosol/cloud size and microphysical properties. Aerosol size and microphysical properties retrieved from multi-wavelength Raman lidar measurements were compared with simultaneous and co-located in-situ measurements.

Sign in / Sign up

Export Citation Format

Share Document