The European aerosol research lidar network (EARLINET): an overview

The European Aerosol Research LIdar NETwork (EARLINET) is the first aerosol lidar network on a continental scale with the main goal to provide a comprehensive, quantitative, and statistically significant database for the aerosol distribution over Europe. Next, we present EARLINET along with the main network activities.Peer ReviewedPostprint (published version

Concept design, analysis, and Integration of the new U.P.C. multispectral lidar system

The increasing need for range-resolved aerosol and water-vapour atmospheric observation networks worldwide has given rise to multi-spectral LIDARs (Light Detection and Ranging, a synonym of laser radar) as advanced remote sensing sensors. This Ph.D. presents the design, integration and analysis of the new 6-channel multispectral elastic/Raman LIDAR for aerosol and water-vapour content monitoring developed at the Remote Sensing Lab. (RSLAB) of the Universitat Polit ecnica de Catalunya (UPC). It is well known that the combination of at least three elastic and two Raman nitrogen channels are su cient to enable retrieval of the optical and microphysical properties of aerosols with a key impact on climate change variables. The UPC lidar is part of the EARLINET (European Aerosol Research Lidar Network) -GALION (Global Atmospheric Watch Atmospheric Lidar Observation Network), a ground-based continental network including more than 28 stations. Currently, only 8 of the 28 EARLINET stations are of such advanced type. This Ph.D. speci cally focuses on: (1) Concept link-budget instrument design and overlap factor assessment. The former includes opto-atmospheric parameter modelling and assessment of backscattered power and SNR levels, and maximum system range for the di erent reception channels (3 elastic, and 2 aerosol and 1 water-vapour Raman channels, ultraviolet to near-infrared bands). The latter studies the laser-telescope crossover function (or overlap function) by means of a novel raytracing Gaussian model. The problem of overlap function computation and its near-range sensitivity for medium size aperture (f=10, f=11) bi-axial tropospheric lidar systems using both detector and ber-optics coupling alternatives at the telescope focal-plane is analysed using this new ray-tracing approach, which provides a much simpler solution than analyticalbased methods. Sensitivity to laser divergence, eld-lens and detector/ ber positions, and ber's numerical aperture is considered. (2) Design and opto-mechanical implementation of the 6-channel polychromator (i.e., the spectrally selective unit in reception). Design trade-o s concerning light collimation, end-to-end transmissivity, net channel responsivity, and homogeneous spatial light distribution onto the detectors' active area discussed. (3) System integration and validation. This third part is two fold: On one hand, fi rst-order backscatter-coe cient error bounds (a level-1 data product) for the two-component elastic lidar inversion algorithm are estimated for both random (observation noise) and systematic error sources (user's uncertainty in the backscatter-coe cient calibration, and user's uncertainty in the aerosol extinction-to-backscatter lidar ratio). On the other hand, the multispectral lidar so far integrated is described at both hardware and control software level. Statistical validation results for the new UPC lidar (today in routine operation) in the framework of SPALI-2010 intercomparison campaign are presented as part of EARLINET quality assurance / optimisation of instruments' program. The methodology developed in the rst part of this Ph.D. has successfully been applied to the speci cation case study of the IFAE/UAB lidar system, which will be installed and operated at the Cherenkov Telescope Array (CTA) observatory. Finally, specs for automated unmanned unattended lidar operation with service times close to 365/24 are presented at the end of this Ph.D. in response to the increasing demand for larger observation times and availability periods of lidar stations

Earlinet Approach to Optimisation of Individual Network Instruments with the Aim of Homogenisation of Aerosol Data Products and Increased Data Coverage

The European Aerosol Research LIdar NETwork (EARLINET) is an aerosol lidar network on a continental scale. EARLINET is now a leading network in qualitycontrolled quantitative aerosol profiling performing a schedule of routine measurements and presently consists of 28 stations distributed over Europe. The construction of an un-biased spatio-temporal database of vertical profiles of aerosol optical properties on a regional scale for climate and air quality research is the main objective of EARLINET and is accomplished through application of Raman lidars. One of the tasks in the EC-funded project EARLINET-ASOS is to optimize individual instruments with the aim of homogenization of aerosol data products over the network and increased data coverage by automation. This task is approached by selection of optimal solutions existing in the pool of individual stations. This is done for components, subsystems as well as for system integration. In system integration emphasis lies on automation to reduce the amount of manpower needed, to improve temporal coverage, and to make performance independent from individual operators. The procedure to perform these tasks is outlined and the set of tools enabling the assessment of performance under development is described

Towards Interoperable Research Infrastructures for Environmental and Earth Sciences

This open access book summarises the latest developments on data management in the EU H2020 ENVRIplus project, which brought together more than 20 environmental and Earth science research infrastructures into a single community. It provides readers with a systematic overview of the common challenges faced by research infrastructures and how a ‘reference model guided’ engineering approach can be used to achieve greater interoperability among such infrastructures in the environmental and earth sciences. The 20 contributions in this book are structured in 5 parts on the design, development, deployment, operation and use of research infrastructures. Part one provides an overview of the state of the art of research infrastructure and relevant e-Infrastructure technologies, part two discusses the reference model guided engineering approach, the third part presents the software and tools developed for common data management challenges, the fourth part demonstrates the software via several use cases, and the last part discusses the sustainability and future directions

EARLINET approach to optimisation of individual network instruments with the aim of homogenisation of aerosol data products and increased data coverage

The European Aerosol Research LIdar NETwork (EARLINET) is an aerosol lidar network on a continental scale. EARLINET is now a leading network in qualitycontrolled quantitative aerosol profiling performing a schedule of routine measurements and presently consists of 28 stations distributed over Europe. The construction of an un-biased spatio-temporal database of vertical profiles of aerosol optical properties on a regional scale for climate and air quality research is the main objective of EARLINET and is accomplished through application of Raman lidars. One of the tasks in the EC-funded project EARLINET-ASOS is to optimize individual instruments with the aim of homogenization of aerosol data products over the network and increased data coverage by automation. This task is approached by selection of optimal solutions existing in the pool of individual stations. This is done for components, subsystems as well as for system integration. In system integration emphasis lies on automation to reduce the amount of manpower needed, to improve temporal coverage, and to make performance independent from individual operators. The procedure to perform these tasks is outlined and the set of tools enabling the assessment of performance under development is described

Towards a better characterization of submicron aerosol in the Mediterranean basin

[eng] Atmospheric aerosol is an ensemble of atmospheric pollutants with a severe impact on human health and Earth climate. Particulate Matter (PM) effects vary depending on the composition and size. However, current air quality guidelines (AQG) from WHO and from the EU Commission only define threshold standards for bulk PM10 and PM2.5 concentrations. In terms of health, the smaller the particles, the deeper they penetrate into the respiratory system, and they can even diffuse into the bloodstream and circulate to other parts of the organism. The adverse effects on the tissues in which they are deposited depend on the PM composition. Regarding climate, PM size and composition relevantly affect many aerosol-radiation direct and indirect interactions, which regulate troposphere temperature. Consequently, the consideration of these properties is relevant for present and future climate descriptions. Barcelona, the city where this study focuses, is located in the Mediterranean basin, a region with high complexity in terms of air pollution, hence, the nature of this enclave requires thorough monitoring of PM in order to protect the population from exposition accurately. This dissertation focuses on submicronic aerosol evolution over the last decade, with a more detailed study for May 2014-May 2015 and September 2017-October 2018. The objective of this thesis is to describe the PM1 sources in Barcelona by means of source apportionment (SA) techniques. The Positive Matrix Factorisation (PMF) algorithm is one of the most widely used approaches for SA and is the tool used in this dissertation. A secondary aim of this study is the improvement of the SA methodology itself. This is accomplished by testing the outcomes of new methodologies involving the more automatic analysis and dataset junction with several approaches. A field-deployed aerosol mass spectrometer was used at the Barcelona site for continuous PM1 measurements, and SA was performed on Organic Aerosol (OA). First, SA was tackled from a conventional methodology, the seasonal PMF, then, the novel rolling PMF methodology was tested and compared to the fore one. Finally, a comprehensive PM1 SA was performed based on an ensemble of different datasets coming from a variety of measurement techniques. These steps enabled a progressive aerosol composition understanding and acknowledgement of subsequent aerosol trends. A PM1 concentrations decrease was found in the 2014-2018 period, a trend confirmed by other studies at the site. Its relative composition changed significantly; a decrease was found for SO42-, BC, and NH4+, while NO3- increased and OA levels were found stable. The OA SA revealed that its sources were: secondary OA (SOA, >55-70%), road traffic OA (12-19%), cooking-like OA (14-18%), and biomass burning OA (4-6%). These sources are similar to those reported in other sites across the Mediterranean region. In this study, all the primary OA sources were found in a clear decrease from 2014 to 2018. An increasing SOA proportion and SOA oxidation state were also observed. These increments could be explained by a likely increase in the oxidation capacity of the atmosphere, related to the accumulation of oxidative radicals reported in many cities. In order to bridge the possible inter-annual variability in that period, the time period was elongated (2014-2021) detecting the same underlying trends. With the aim of further climate and health impact aerosol impact assessment, this thesis provides mid-term PM1 sources diagnosis. SOA is especially concerning in terms of health effects, hence this pollutant is to be continuously monitored to deeply understand its precursors and formation mechanisms to design effective abatement policies.[cat] L’aerosol atmosfèric és un conjunt de contaminants atmosfèrics amb un impacte sever sobre la salut humana i el clima. Els efectes del material particulat (PM) varien depenent de la seva composició i mida. Barcelona, la ciutat en què es centra aquest estudi, està localitzada a la conca mediterrània, una regió d’alta complexitat en termes de contaminació de l’aire. Per tant, requereix un monitoratge conscienciós del PM per tal de protegir la població acuradament de la seva exposició. Aquesta tesi es focalitza en l’evolució del PM submicrònic (PM1) al llarg de l’última dècada, amb un estudi més detallat per als períodes maig 2014 - maig 2015 i setembre 2017 - octubre 2018. L'objectiu d'aquesta tesi és descriure les fonts de PM1 a Barcelona per mitjà de tècniques de contribució de fonts (SA). L'algoritme de Factorització de Matriu Positiva (PMF) és un dels enfocaments més utilitzats per al SA o és l'eina emprada per a aquesta dissertació. Un objectiu secundari d'aquesta tesi és la millora de la pròpia metodologia del SA. Això és executat per mitjà del testatge a través de diferents metodologies. Les mesures de PM1 es van dur a terme a través d’un espectròmetre de masses instal·lat a l'estació de Barcelona. El SA va ser executat per a l'Aerosol Orgànic (OA) submicrònic mesurat a partir d’aquest instrument, aplicant diferents metodologies per a avaluar-ne l’exactitud. Finalment, un estudi detallat del SA de PM1 va ser executat basat en un conjunt de dades provinents de diferents tècniques de mesura. Aquests passos van permetre la comprensió progressiva de la composició i el reconeixement de les tendències subjacents de l'aerosol. Un dels resultats més rellevants consisteix en la detecció d'una tendència creixent del SOA independentment de la disminució del PM1, relacionat amb el decreixement de l'OA primari. A més, pel que fa al SA, aquesta tesi proposa diverses modificacions del protocol. El SOA és especialment preocupant pels seus efectes en la salut, per tant, aquest contaminant ha de ser contínuament monitorejat amb tècniques de SA per tal d'entendre els seus precursors i mecanismes de formació amb l'objectiu de dissenyar mesures de mitigació efectives

Towards a better characterization of submicron aerosol in the Mediterranean basin

Programa de Doctorat en Física / Tesi realitzada a l'Institut de Diagnòstic Ambiental i Estudis de l'Aigua (IDAEA - CSIC)[eng] Atmospheric aerosol is an ensemble of atmospheric pollutants with a severe impact on human health and Earth climate. Particulate Matter (PM) effects vary depending on the composition and size. However, current air quality guidelines (AQG) from WHO and from the EU Commission only define threshold standards for bulk PM10 and PM2.5 concentrations. In terms of health, the smaller the particles, the deeper they penetrate into the respiratory system, and they can even diffuse into the bloodstream and circulate to other parts of the organism. The adverse effects on the tissues in which they are deposited depend on the PM composition. Regarding climate, PM size and composition relevantly affect many aerosol-radiation direct and indirect interactions, which regulate troposphere temperature. Consequently, the consideration of these properties is relevant for present and future climate descriptions. Barcelona, the city where this study focuses, is located in the Mediterranean basin, a region with high complexity in terms of air pollution, hence, the nature of this enclave requires thorough monitoring of PM in order to protect the population from exposition accurately. This dissertation focuses on submicronic aerosol evolution over the last decade, with a more detailed study for May 2014-May 2015 and September 2017-October 2018. The objective of this thesis is to describe the PM1 sources in Barcelona by means of source apportionment (SA) techniques. The Positive Matrix Factorisation (PMF) algorithm is one of the most widely used approaches for SA and is the tool used in this dissertation. A secondary aim of this study is the improvement of the SA methodology itself. This is accomplished by testing the outcomes of new methodologies involving the more automatic analysis and dataset junction with several approaches. A field-deployed aerosol mass spectrometer was used at the Barcelona site for continuous PM1 measurements, and SA was performed on Organic Aerosol (OA). First, SA was tackled from a conventional methodology, the seasonal PMF, then, the novel rolling PMF methodology was tested and compared to the fore one. Finally, a comprehensive PM1 SA was performed based on an ensemble of different datasets coming from a variety of measurement techniques. These steps enabled a progressive aerosol composition understanding and acknowledgement of subsequent aerosol trends. A PM1 concentrations decrease was found in the 2014-2018 period, a trend confirmed by other studies at the site. Its relative composition changed significantly; a decrease was found for SO42-, BC, and NH4+, while NO3- increased and OA levels were found stable. The OA SA revealed that its sources were: secondary OA (SOA, >55-70%), road traffic OA (12-19%), cooking-like OA (14-18%), and biomass burning OA (4-6%). These sources are similar to those reported in other sites across the Mediterranean region. In this study, all the primary OA sources were found in a clear decrease from 2014 to 2018. An increasing SOA proportion and SOA oxidation state were also observed. These increments could be explained by a likely increase in the oxidation capacity of the atmosphere, related to the accumulation of oxidative radicals reported in many cities. In order to bridge the possible inter-annual variability in that period, the time period was elongated (2014-2021) detecting the same underlying trends. With the aim of further climate and health impact aerosol impact assessment, this thesis provides mid-term PM1 sources diagnosis. SOA is especially concerning in terms of health effects, hence this pollutant is to be continuously monitored to deeply understand its precursors and formation mechanisms to design effective abatement policies.[cat] L’aerosol atmosfèric és un conjunt de contaminants atmosfèrics amb un impacte sever sobre la salut humana i el clima. Els efectes del material particulat (PM) varien depenent de la seva composició i mida. Barcelona, la ciutat en què es centra aquest estudi, està localitzada a la conca mediterrània, una regió d’alta complexitat en termes de contaminació de l’aire. Per tant, requereix un monitoratge conscienciós del PM per tal de protegir la població acuradament de la seva exposició. Aquesta tesi es focalitza en l’evolució del PM submicrònic (PM1) al llarg de l’última dècada, amb un estudi més detallat per als períodes maig 2014 - maig 2015 i setembre 2017 - octubre 2018. L'objectiu d'aquesta tesi és descriure les fonts de PM1 a Barcelona per mitjà de tècniques de contribució de fonts (SA). L'algoritme de Factorització de Matriu Positiva (PMF) és un dels enfocaments més utilitzats per al SA o és l'eina emprada per a aquesta dissertació. Un objectiu secundari d'aquesta tesi és la millora de la pròpia metodologia del SA. Això és executat per mitjà del testatge a través de diferents metodologies. Les mesures de PM1 es van dur a terme a través d’un espectròmetre de masses instal·lat a l'estació de Barcelona. El SA va ser executat per a l'Aerosol Orgànic (OA) submicrònic mesurat a partir d’aquest instrument, aplicant diferents metodologies per a avaluar-ne l’exactitud. Finalment, un estudi detallat del SA de PM1 va ser executat basat en un conjunt de dades provinents de diferents tècniques de mesura. Aquests passos van permetre la comprensió progressiva de la composició i el reconeixement de les tendències subjacents de l'aerosol. Un dels resultats més rellevants consisteix en la detecció d'una tendència creixent del SOA independentment de la disminució del PM1, relacionat amb el decreixement de l'OA primari. A més, pel que fa al SA, aquesta tesi proposa diverses modificacions del protocol. El SOA és especialment preocupant pels seus efectes en la salut, per tant, aquest contaminant ha de ser contínuament monitorejat amb tècniques de SA per tal d'entendre els seus precursors i mecanismes de formació amb l'objectiu de dissenyar mesures de mitigació efectives

Towards Interoperable Research Infrastructures for Environmental and Earth Sciences

This open access book summarises the latest developments on data management in the EU H2020 ENVRIplus project, which brought together more than 20 environmental and Earth science research infrastructures into a single community. It provides readers with a systematic overview of the common challenges faced by research infrastructures and how a ‘reference model guided’ engineering approach can be used to achieve greater interoperability among such infrastructures in the environmental and earth sciences. The 20 contributions in this book are structured in 5 parts on the design, development, deployment, operation and use of research infrastructures. Part one provides an overview of the state of the art of research infrastructure and relevant e-Infrastructure technologies, part two discusses the reference model guided engineering approach, the third part presents the software and tools developed for common data management challenges, the fourth part demonstrates the software via several use cases, and the last part discusses the sustainability and future directions