A5080596362- Atmospheric aerosols and clouds
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Fire effects on ecosystems
- Atmospheric Ozone and Climate
- Meteorological Phenomena and Simulations
- Remote Sensing and LiDAR Applications
- Advanced Optical Sensing Technologies
- Spectroscopy and Laser Applications
- Remote Sensing in Agriculture
- Calibration and Measurement Techniques
- Geophysics and Gravity Measurements
- Air Quality Monitoring and Forecasting
- Aeolian processes and effects
- 3D Surveying and Cultural Heritage
- Geochemistry and Geologic Mapping
- Optical Systems and Laser Technology
- Solar Radiation and Photovoltaics
- Vehicle emissions and performance
- Plant responses to elevated CO2
- Underwater Vehicles and Communication Systems
- Spacecraft and Cryogenic Technologies
- Air Quality and Health Impacts
- Water Quality Monitoring Technologies
- Earthquake Detection and Analysis
National Institute of Research and Development for Optoelectronics
2018-2024
Met Office
2016-2024
European Commission
2023
Aberystwyth University
2018
Joint Research Centre
2010-2016
Howard University
2007-2009
NSF National Center for Atmospheric Research
2009
Johns Hopkins University
2004-2007
Ruhr University Bochum
2007
University of Maryland, Baltimore
2004
Abstract. The eruption of the Icelandic volcano Eyjafjallajökull in April–May 2010 represents a "natural experiment" to study impact volcanic emissions on continental scale. For first time, quantitative data about presence, altitude, and layering cloud, conjunction with optical information, are available for most parts Europe derived from observations by European Aerosol Research Lidar NETwork (EARLINET). Based multi-wavelength Raman lidar systems, EARLINET is only instrument worldwide that...
Abstract. This paper introduces the recent European Aerosol Research Lidar Network (EARLINET) quality-assurance efforts at instrument level. Within two dedicated campaigns and five single-site intercomparison activities, 21 EARLINET systems from 18 stations were intercompared between 2009 2013. A comprehensive strategy for campaign setup data evaluation has been established. Eleven nine participated in Intercomparison (EARLI09). In this campaign, three reference qualified which served as...
Abstract. On 15–16 October 2017, ex-hurricane Ophelia passed to the west of British Isles, bringing dust from Sahara and smoke Portuguese forest fires that was observable naked eye reported in UK's national press. We report here detailed observations this event using UK operational lidar sun-photometer network, established for early detection aviation hazards, including volcanic ash. also use ECMWF ERA5 wind field data MODIS imagery examine aerosol transport. The observations, taken...
Abstract. Layers of aerosol at heights between 2 and 11 km were observed with Raman lidars in the UK 23 31 May 2016. A network these lidars, supported by ceilometer observations, is used to map extent its optical properties. Space-borne lidar profiles show that originated from forest fires over western Canada around 17 May, indeed properties – weak volume depolarisation (<5 %) a ratio 355 nm range 35–65 sr consistent long-range transport fire smoke. The event was unusual persistence smoke...
Abstract A high-performance Raman lidar operating in the UV portion of spectrum has been used to acquire, for first time using a single lidar, simultaneous airborne profiles water vapor mixing ratio, aerosol backscatter, extinction, depolarization and research mode measurements cloud liquid water, droplet radius, number density. The Airborne Spectroscopic Lidar (RASL) system was installed Beechcraft King Air B200 aircraft flown over mid-Atlantic United States during July–August 2007 at...
Abstract. This study focuses on the aerosol hygroscopic properties as determined from ground-based measurements and Mie theory. Usually, are taken in dry conditions order to have a consistency within networks. The dependence of various optical characteristics (e.g. absorption, scattering, backscattering or extinction coefficients) relative humidity has therefore be established determine their values atmosphere, where can reach high values. We calculated mean monthly diurnal growth factor at...
Abstract. The methodology of analysing the biomass burning events recorded in database European Aerosol Research Lidar Network framework Aerosol, Clouds and Trace Gases Infrastructure is presented. period 2008–2017 was chosen to analyse all stored under Forest Fire category for a total 14 stations available. data provided ranged from complete datasets (particle backscatter, extinction linear depolarization ratio profiles) single profiles backscatter coefficient profile). Smoke layers...
Comparisons of Tropospheric Emission Spectrometer (TES) water vapor retrievals with in situ measurements are presented. Global comparisons TES nighttime National Centers for Environmental Prediction RS90/RS92 radiosondes show a small (<5%) moist bias the lower troposphere (standard deviation ∼20%), increasing to maximum ∼15% (with standard reaching ∼40%) upper troposphere. This respect sonde increases between ∼300–200 hPa. The this region reaches values ∼40%. It is important note that...
High spatial and temporal resolution elastic backscatter lidar data from Baltimore are analyzed with a near‐end approach to estimate vertical profiles of the aerosol extinction coefficient. The makes use (1) scattering coefficient measured at surface nephelometer (0.530 μm), (2) level particle size distribution, (3) refractive index calculated using Mie theory boundary condition for equation. There was broad range atmospheric turbidity due strong haze event, which occurred because smoke...
Highly time-resolved measurements of PM2.5, its major constituents, particle size distributions (9 nm to 20 μ m), CO, NO/NO2, and O3, meteorological parameters were made from February through November 2002, at the Baltimore Supersite Ponca St. using commercial prototype semi-continuous instruments. The average PM2.5 mass concentration during study period was 16.9 g/m3 a total 29 pollution episodes, each in which 24-h averaged concentrations exceeded 30.0 for one or more days, observed....
Abstract Water vapor mixing ratio retrieval using the Howard University Raman lidar is presented with emphasis on three aspects: (i) comparison of collocated radiosondes and lidar, (ii) investigation relationship between atmospheric state variables relative performance sonde (in particular, their poor agreement), (iii) satellite-based measurements. The measurements were acquired during Vapor Validation Experiment Sondes/Satellites 2006 campaign. Ensemble averaging water data from 10...
During the eruption of Eyjafjallajökull in 2010, Met Office ceilometers (Laser Cloud Based Recorders - LCBR) provided reasonable information about volcanic ash plumes over United Kingdom [1]. This capability triggered development an operational system to provide quick looks range corrected signals (RCS) near-real-time (NRT). Moreover, acquired eleven Jenoptik supplement ceilometer network. The combined network became 2012 and currently comprises a total 43 reporting backscatter profiles NRT....
We estimate the overlap function (accounting for near-field effects) an airborne nadir-mounted lidar, based on multi-angle measurements of atmospheric scene obtained during two flights. For each layer, a regression logarithm range-corrected signal versus secant off-nadir angle allowed evaluation optical depth and backscattering coefficient multiplied by lidar constant. These quantities allow computation unaffected effect, then determination correction function. Its evolution over time can...
Abstract The temperature dependence of molecular backscatter coefficients must be taken into account when narrowband interference filters are used in lidar measurements. Thus, the spectral differential cross section molecules involved backscattering radiation has to calculated or measured and filter transmission efficiency known. present paper is intended describe an easily reproducible manner procedure calculating temperature-dependent functions introduced equations, including computation...
Abstract. This paper introduces the recent EARLINET quality-assurance efforts at instrument level. Within two dedicated campaigns and five single-site intercomparison activities 21 systems from 18 stations were intercompared between 2009 2013. A comprehensive strategy for campaign setup data evaluation has been established. Eleven nine participated in Lidar Intercomparison (EARLI09). In this campaign, three reference qualified which served as traveling standards thereafter. other have...
Abstract An improved measurement methodology and a data-processing technique for multiangle data obtained with an elastic scanning lidar in clear atmospheres are introduced. Azimuthal slope scans combined to reduce the atmospheric heterogeneity. Vertical profiles of optical depth intercept (proportional logarithm backscatter coefficient) determined. The purpose this approach is identify remove points that distort regression analysis results order improve accuracy retrieved intercept. In...
This study compares the aerosol backscatter and extinction coefficients retrieved from vertical elastic Raman channels with those derived measurements multiangle channels. Retrievals simulated signals at 355 nm, 387 532 607 nm are compared (at 15 elevation angles) nm. The atmosphere is considered horizontally homogeneously stratified. For coefficient, solution considered. retrievals channel compared. comparison shows that in presence of horizontal homogeneity, provide more reliable results,...
The Met Office completed the deployment of ten lidars (UV Raman and depolarization), each accompanied by a sunphotometer (polarized model), to provide quantitative monitoring volcanic ash over UK for VAAC London. range corrected signal volume depolarization ratio in near-real time. sunphotometers deliver aerosol optical depth, Ångstrom exponent degree linear polarization. Case study analyses Saharan dust events (as proxy ash) are presented.
Doppler wind lidar measurements were used for the first time in Romania to analyse and turbulence statistics a peri-urban site located at Măgurele, southwest of Bucharest. Vertical scanning between December 2019 November 2021 processed using an existing toolbox. The over two-year period performed on seasonal diurnal cycle bases. analyses showed horizontal speed, with lower values during daytime. In upper part planetary boundary layer (PBL), speed is lowest day highest night (near surface,...
The eruption of Eyjafjallajökull in 2010 has triggered the rapid development volcanic ash remote sensing activities at Met Office. Volcanic qualitative and quantitative mapping have been achieved using lidar on board Facility for Airborne Atmospheric Measurements (FAAM) research aircraft, improved satellite retrieval algorithms. After eruption, a new aircraft facility, Office Civil Contingencies Aircraft (MOCCA), set up to enable response, network ground-based sites with lidars...
Abstract. Biomass burning episodes measured at 14 stations of the European Aerosol Research Lidar Network (EARLINET) over 2008–2017 were analysed using methodology described in "Biomass events by lidars EARLINET – Part 1: Data analysis methodology" (Adam et al., 2020, this issue). The smoke layers identified lidar optical properties profiles. A number 795 for which we least one intensive parameter was analysed. These geographically distributed as follows: 399 observed South-East Europe, 119...
A near-real-time automatic detection system, based on the synergy of continuous measurements taken by a ceilometer and photometer, has been implemented in order to detect lofted atmospheric aerosol layers estimate load. When heavy-loaded conditions are detected (defined significant deviation optical properties from 10-year climatology), obtained for above 2500 m, an alert is sent scientists Romanian Lidar Network (ROLINET) further monitor event. The Hybrid Single-Particle Lagrangian...
Classical and quantum formulations are used to estimate Rayleigh scattering within lidar signals. Within the classical approach, three scenarios characterize atmospheric molecular composition: 2-component atmosphere (N2 O2), 4-component (N2, O2, Ar, CO2), 5-component CO2, water vapor). First, analysis focuses on scattering, showing relative difference between approach. The in 2(4)-component is below ∼1%. second retrieval of aerosol backscatter extinction coefficients effect different...
Abstract. This study focuses on the aerosol hygroscopic properties as determined from ground-based measurements and Mie theory. Usually, are taken in dry conditions to ensure data consistency within networks. The dependence of various optical characteristics (e.g. absorption, scattering, backscattering or extinction coefficients) relative humidity has therefore be established order determine their values atmosphere, where can reach high values. We calculated mean monthly diurnal growth...