Determination of nocturnal aerosol properties from a combination of lunar photometer and lidar observations

2015 ◽  
Author(s):  
Donghui Li ◽  
Zhengqiang Li ◽  
Yang Lv ◽  
Ying Zhang ◽  
Kaitao Li ◽  
...  
Keyword(s):  
Lidar Observations ◽  
Aerosol Properties

scholarly journals Transport of Canadian forest fire smoke over the UK as observed by lidar

2018 ◽  
Author(s):  
Geraint Vaughan ◽  
Adam P. Draude ◽  
Hugo M. A. Ricketts ◽  
David M. Schultz ◽  
Mariana Adam ◽  
...  
Keyword(s):  
Forest Fire ◽  
Forest Fires ◽  
Western Canada ◽  
North West ◽  
Fire Smoke ◽  
Range Transport ◽  
Lidar Ratio ◽  
The Uk ◽  
Lidar Observations ◽  
Aerosol Properties

Abstract. Layers of aerosol at heights between 2 and 11 km were observed with Raman lidars in the UK between 23 and 31 May 2016. A network of such lidars, supported by ceilometer observations, is used to map the extent of the aerosol and its optical properties. Spaceborne lidar profiles show that the aerosol originated from forest fires over Western Canada around 17 May, and indeed the aerosol properties – weak depolarisation and a lidar ratio at 355 nm in the range 35–65 sr – were consistent with long-range transport of forest fire smoke. The event was unusual in its persistence – the smoke plume was drawn into an atmospheric block that kept it above North-west Europe for nine days. Lidar observations show how the smoke layers became optically thinner during this period, but the lidar ratio and aerosol depolarisation showed little change.

scholarly journals Interrelations between surface, boundary layer, and columnar aerosol properties over a continental urban site

2018 ◽  
Author(s):  
Dongxiang Wang ◽  
Dominika Szczepanik ◽  
Iwona S. Stachlewska
Keyword(s):  
Boundary Layer ◽  
Optical Properties ◽  
Urban Site ◽  
Surface Boundary ◽  
Backscatter Coefficient ◽  
Surface Boundary Layer ◽  
Lidar Observations ◽  
532 Nm ◽  
Aerosol Properties

Abstract. PollyXT Raman Polarization Lidar observations were performed at the Remote Sensing laboratory in Warsaw (52.2109° N, 20.9826° E), Poland, in the framework of the European Aerosol Research Lidar Network (EARLINET) and the Aerosols, Clouds and Trace gases Research Infrastructure (ACTRIS). Data collected in July, August and September of 2013, 2015 and 2016 were analysed using the classical Raman approach. In total 202 sets of profiles of the particle extinction and backscatter coefficient, and linear particle depolarization ratio at 355 nm and 532 nm were derived for statistical investigations (EARLINET/ACTRIS Data Base). The main analysis was focused on intensive optical properties obtained within aerosol boundary layer (ABL). The interrelationships of different optical properties inside ABL are discussed for different periods: entire day, nocturnal time and sunrise/sunset time. In addition, the lidar derived boundary layer optical properties were compared with the columnar daytime aerosol properties derived from radiometer (MFR-7, PolandAOD-NET) and photometer (C318, AERONET). Relationships of these and surface in-situ measurements of particulate matter with an aerodynamic diameter

scholarly journals CCN concentration and INP-relevant aerosol profiles in the Saharan Air Layer over Barbados from polarization lidar and airborne in situ measurements

2019 ◽  
Author(s):  
Moritz Haarig ◽  
Adrian Walser ◽  
Albert Ansmann ◽  
Maximilian Dollner ◽  
Dietrich Althausen ◽  
...  
Keyword(s):  
Surface Area ◽  
Cloud Condensation Nuclei ◽  
Number Concentration ◽  
In Situ Measurements ◽  
Saharan Air Layer ◽  
Lidar Measurements ◽  
Research Aircraft ◽  
Lidar Observations ◽  
Aerosol Properties

Abstract. The present study aims to validate lidar retrievals of cloud-relevant aerosol properties by using polarization lidar and coincident airborne in situ measurements in the Saharan Air Layer over the Barbados region. Vertical profiles of the number concentration of cloud condensation nuclei (CCN), large particles (diameter d > 500 nm), surface area, and ice nucleating particles (INP) are estimated from the lidar measurements and compared with CCN concentrations and the INP-relevant aerosol properties in situ measured with aircraft in the framework of the Saharan Aerosol Long-range Transport and Aerosol–Cloudinteraction Experiment (SALTRACE) in summer 2013. The CCN number concentrations derived from lidar observations were up to a factor of two higher than the ones measured in situ on board the research aircraft Falcon. However, a reasonable agreement was obtained when taking the lidar uncertainty into account. The number concentration of particles with dry radius > 250 nm and the surface area concentration obtained from the lidar observations and used as input for the INP parameterizations agreed well (

scholarly journals Enhancement of aerosol characterization using synergy of lidar and sun – photometer coincident observations: the GARRLiC algorithm

2013 ◽  
Vol 6 (2) ◽  
pp. 2253-2325 ◽  
Author(s):  
A. Lopatin ◽  
O. Dubovik ◽  
A. Chaikovsky ◽  
Ph. Goloub ◽  
T. Lapyonok ◽  
...  
Keyword(s):  
Refractive Index ◽  
Size Distribution ◽  
Complex Refractive Index ◽  
Single Scattering ◽  
Inversion Algorithm ◽  
Multi Wavelength ◽  
Lidar Observations ◽  
Aerosol Properties ◽  
Different Altitudes ◽  
Aerosol Type

Abstract. Currently most of experiments pursuing comprehensive characterization of atmosphere include coordinated observations by both lidar and radiometers in order to obtain important complimentary information about aerosol properties. The passive observations by radiometers from ground are mostly sensitive to the properties of aerosol in total atmospheric column and have very limited sensitivity to vertical structure of the atmosphere. Such observations are commonly used for measuring aerosol optical thickness and deriving the information about aerosol microphysics including aerosol particles shape, size distribution, and complex refractive index. In a contrast, lidar observations of atmospheric responses from different altitudes to laser pulses emitted from ground are designed to provide accurate profiling of the atmospheric properties. The interpretation of the lidar observation generally relies on some assumptions about aerosol type and loading. Here we present the GARRLiC algorithm (Generalized Aerosol Retrieval from Radiometer and Lidar Combined data) that simultaneously inverts co-incident lidar and radiometer observations and derives a united set of aerosol parameters. Such synergetic retrieval is expected to result in additional enhancements in derived aerosol properties because the backscattering observations by lidar add some sensitivity to the columnar properties of aerosol, while radiometric observations provide sufficient constraints on aerosol type and loading that generally are missing in lidar signals. GARRLiC is based on AERONET algorithm for inverting combined observations by radiometer and multi-wavelength elastic lidar observations. It is expected that spectral changes of backscattering signal obtained by multi-wavelength lidar at different altitudes provide some sensitivity to the vertical variability of aerosol particle sizes. In order to benefit from this sensitivity the algorithm is set to derive not only the vertical profile of total aerosol concentration but it also differentiates between the contributions of fine and coarse modes of aerosol. The detailed microphysical properties are assumed height independent and different for each mode and expected to be derived as a part of the retrieval. Thus, the GARRLiC inversion algorithm retrieves vertical distribution of both fine and coarse aerosol concentrations as well as the size distribution, complex refractive index and single scattering albedo for each mode. The potential and limitations of the method are demonstrated by the series of sensitivity tests. The practical outcome of the approach is illustrated by applications of the algorithm to the real lidar and radiometer observations obtained over selected AERONET site.

scholarly journals Continuous monitoring of the boundary-layer top with lidar

2008 ◽  
Vol 8 (3) ◽  
pp. 10749-10790 ◽  
Author(s):  
H. Baars ◽  
A. Ansmann ◽  
R. Engelmann ◽  
D. Althausen
Keyword(s):  
Boundary Layer ◽  
Weather Forecast ◽  
Forecast Model ◽  
Raman Lidar ◽  
Data Set ◽  
Weather Forecast Model ◽  
One Year ◽  
The One ◽  
Lidar Observations

Abstract. Continuous lidar observations of the top height of the boundary layer (BL top) have been performed at Leipzig (51.3° N, 12.4° E), Germany, since August 2005. The results of measurements taken with a compact, automated Raman lidar over a one-year period (February 2006 to January 2007) are presented. Four different methods for the determination of the BL top are discussed. The most promising technique, the wavelet covariance algorithm, is improved by implementing some modifications so that an automated, robust retrieval of BL depths from lidar data is possible. Three case studies of simultaneous observations with the Raman lidar, a vertical-wind Doppler lidar, and accompanying radiosonde profiling of temperature and humidity are discussed to demonstrate the potential and the limits of the four lidar techniques at different aerosol and meteorological conditions. The lidar-derived BL top heights are compared with respective values derived from predictions of the regional weather forecast model COSMO of the German Meteorological Service. The comparison shows a general underestimation of the BL top by about 20% by the model. The statistical analysis of the one-year data set reveals that the seasonal mean of the daytime maximum BL top is 1400 m in spring, 1800 m in summer, 1200 m in autumn, and 800 m in winter at the continental, central European site. BL top typically increases by 100–300 m per hour in the morning of convective days.

Sign in / Sign up

Export Citation Format

Share Document