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French LiDAR research: From fundamental science to industrial applications

Photo: Hervé Dole

French LiDAR research: From fundamental science to industrial applications

A recent feature article published in Photoniques (issue 136) offers a broad overview of LiDAR remote sensing in France, covering the technology’s scientific foundations, current research directions, and ongoing efforts to translate laboratory developments into operational systems.

The article, co-authored by researchers from several leading French institutions, including ONERA, LATMOS, LOA, LMD, iLM and Thales, describes how LiDAR systems exploit the directional and spectral properties of laser light to measure atmospheric constituents, wind fields, aerosol distributions, and terrain topography. As illustrated by the photograph of a laser shot at the Observatoire de Haute-Provence (OHP), these systems operate across a wide range of platforms, from ground-based observatories to airborne and spaceborne configurations.

Photograph of a lidar measurement at the Haute Provence Observatory (OHP – Photo: Hervé Dole).

On the measurement side, the article discusses advances in both direct-detection and coherent-detection architectures. For atmospheric characterisation, techniques combining Raman scattering, elastic backscatter, polarimetry, and laser-induced fluorescence allow increasingly fine classification of aerosol types, distinguishing mineral dust, pollen, urban particles and smoke, as shown in the depolarisation–fluorescence diagram reproduced from recent ACTRIS network publications. Long-term ozone profile series measured at French observatories are noted as among the longest continuous records of their kind worldwide.

The article also highlights successful technology transfers from academic research to industry. In this context, the AGORA-Lab, a joint laboratory between LOA and CIMEL, is cited as an example of collaborative development that has led to compact, automated LiDAR instruments, including Raman and multi-wavelength fluorescence systems, now integrated within the ACTRIS European research infrastructure.

The national LiDAR HD programme, illustrated through a point cloud map of central Paris, demonstrates how these technologies are already being deployed at scale for land use, flood risk management and urban planning purposes.

The article concludes that while French LiDAR research maintains a strong international standing, further work on system miniaturisation, cost reduction and automation remains necessary to broaden industrial uptake.

Read more here: https://www.photoniques.com/articles/photon/pdf/2026/01/photon2026-136.pdf

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CE318-T aboard Persévérance

The CE318 photometer aboard Persévérance

Where scientific observation meets ocean adventure

Persévérance official page   |   PHOTONS Mobile campaign page   |   PHOTONS / AERONET France

To understand climate and improve weather forecasting, we must first understand aerosols. These tiny particles suspended in the atmosphere influence the Earth’s radiation balance, cloud formation, visibility, and the movement of air masses across the globe. Over the oceans, their role is especially important. And yet, these immense marine expanses remain among the least documented regions on Earth when it comes to continuous atmospheric observations.

That is what makes the Persévérance campaign so exceptional.

Conceived by explorer Jean-Louis Etienne, Persévérance is a polar-capable schooner designed to support scientific missions in remote marine regions, where observations are rare and logistics remain challenging. By operating far from permanent stations and conventional routes, it offers a unique opportunity to collect valuable environmental data in areas that are still sparsely documented.

Figure 1 – Example of autonomous shipborne photometer operation over the open ocean.

On board, a CIMEL CE318 photometer operated autonomously throughout the voyage, performing day-and-night aerosol observations over the open ocean. Tracking the Sun by day and the Moon by night, the instrument transformed the vessel into a moving atmospheric observatory. Quietly and continuously, it captured the optical signature of aerosols across regions of the world where few instruments ever operate with such regularity.

This deployment is remarkable not only because of the challenge of operating an automatic photometer at sea, but because of the scientific value of the route itself. The open ocean remains one of the great blind spots of atmospheric observation. In these remote marine regions, every reliable measurement is precious for documenting aerosol background conditions, tracking long-range transport, improving satellite validation, and strengthening meteorological and climate studies.

Figure 2 – PHOTONS Mobile campaign snapshot for Persévérance (TourDuMonde #1443), showing the route and measurement record.

The campaign also reflects the strength of the scientific framework behind these observations. The data are part of the PHOTONS / AERONET ecosystem, with PHOTONS representing the French component of AERONET and LOA/CNRS in Lille playing a central role in aerosol observation and photometric data processing. Through this broader international framework, measurements collected far from land acquire even greater value: they can be compared, interpreted, and integrated into a long-term effort to better understand the atmosphere on a global scale.

In this sense, Persévérance was not simply crossing oceans. It was helping reveal them – not only as routes of travel and exploration, but as atmospheric frontiers still waiting to be observed in greater detail.

By extending aerosol monitoring beyond fixed land-based stations, the CE318 deployment aboard Persévérance contributes to a more complete picture of the marine atmosphere. It is a reminder that some of the most valuable observations are still made at the edge of the map, where science follows exploration, and where each measurement brings us closer to a better understanding of climate and weather.

Source links

Click on Lev 1.0 or Lev 1.5 to visualize the measurements.

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ATMOSUD super sites

Urban air quality monitoring at ATMOSUD super sites

CIMEL instruments supporting urban air quality and atmospheric process studies across ATMOSUD and OHP reference sites

ATMOSUD operates a network of long-term atmospheric reference sites in Southern France dedicated to air quality and greenhouse gas studies. These super sites combine in situ measurements, remote sensing observations and modelling tools to better understand pollutant dispersion, atmospheric mixing and emission reduction scenarios at the metropolitan scale.

Within this framework, CIMEL Automatic Aerosol Monitoring Solutions (AAMS) play a key role by providing continuous, high-quality observations of both the vertical and column-integrated structure of the atmosphere.

Figure 1. Map of the SUD–PACA region (left, (a)) and zoomed in on Marseille (right, (b)) showing the location of the measurement stations (blue: Marignane (AER), orange: Corniche (COR), red: Longchamp (LCP), green: La Valentine (LAV)). Arrows in yellow, black, and purple indicate the main wind regimes over the study periods, respectively, sea/land breezes (28%), mistral winds (21%), and eastern winds (17%).

Marseille–Longchamp: an urban reference site for air quality applications

The Marseille–Longchamp site, located in the city centre, is a flagship ATMOSUD urban reference observatory. It captures air quality conditions in a dense urban environment strongly influenced by local emissions, complex meteorology and coastal effects.

A CIMEL CE376 aerosol LiDAR is deployed on the rooftop of the site to continuously monitor atmospheric vertical structure, with a particular focus on atmospheric boundary layer height (ABLH). This parameter is a key driver of pollutant dilution and accumulation in cities. LiDAR observations reveal strong contrasts between wind regimes, such as mistral conditions inducing intense turbulence and deeper mixing layers, and sea–land breeze situations associated with shallow boundary layers and pollutant buildup. These LiDAR-derived mixing height observations provide essential physical context for the interpretation of in situ air quality measurements, strengthening the operational and scientific value of the Marseille–Longchamp site.

Figure 2. Time series of the green channel PR2 for the SM event (a), the WM event (b), the SB event (c), and the WB event (d). Color dots represent the ABLH (pink, black, red, and gray stand for fog, good, bad, and undetermined flags, respectively).

Complementing the LiDAR, a CIMEL CE318 sun photometer provides long-term measurements of aerosol optical properties, contributing to the characterization of the atmospheric column above the urban area.

Figure 3 : Picture of the CE318-T photometer at Marseille–Longchamp site.

Complementary sites: urban, coastal and rural altitude observations

Beyond Marseille–Longchamp, ATMOSUD and its scientific partners operate complementary reference sites covering contrasted environments, including coastal and industrial areas and the Observatoire de Haute-Provence (OHP), a rural high-altitude site representative of background atmospheric conditions.

The OHP site plays a central role in regional atmospheric studies by documenting free-tropospheric conditions, long-range transport and baseline aerosol and gas concentrations. The scientific collaboration between ATMOSUD and OHP enables a consistent interpretation of observations across environments, from urban emission-dominated areas to rural background conditions.

Across this network, CIMEL instruments ensure observational continuity, allowing comparisons between sites and supporting studies of local versus regional contributions to air quality and greenhouse gas signals.

From observations to applications

Data collected at ATMOSUD and OHP super sites feed a wide range of applications, including:

  • interpretation of urban air quality measurements,
  • analysis of pollutant accumulation and dilution regimes,
  • support to atmospheric modelling,
  • evaluation of metropolitan-scale emission reduction scenarios.

By integrating CE376 LiDAR vertical profiling and CE318 photometer column observations within operational reference sites, CIMEL’s AAMS contributes directly to advancing air quality monitoring and atmospheric process understanding in complex urban and regional environments.

Bibliography

  • Xueref-Remy, I., Riandet, A., Bellon, C., Khaykin, S., Blanc, P.-E., Gomez, F., Armengaud, A., Gille, G., Popovici, I., Pascal, N., Podvin, T., and Goloub, P.: Continuous monitoring of atmospheric aerosols by LIDAR remote sensing technics in the south-east of France at the Observatoire de Haute Provence and Marseille Longchamp sites in the framework of ACTRIS-France and of the ANR COoL-AMmetropolis project., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3126, https://doi.org/10.5194/egusphere-egu22-3126, 2022.
  • Riandet, A., Xueref-Remy, I., Popovici, I., Lelandais, L., Armengaud, A., & Goloub, P. (2023). Diurnal and Seasonal Variability of the Atmospheric Boundary-Layer Height in Marseille (France) for Mistral and Sea/Land Breeze Conditions. Remote Sensing, 15(5), 1185. https://doi.org/10.3390/rs15051185
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CE312-T at La Crau (CNES)

Installation of the robotized CE312 radiometer at the La Crau site for CNES

In June 2023, the new robotized version of the CE312 thermal infrared radiometer was installed on a dedicated mast at the La Crau reference site, one of CNES’s strategic Calibration and Validation (CAL/VAL) locations for current and next-generation thermal satellite missions. This installation marks a significant reinforcement of France’s long-term capability to generate the high-quality ground truth data required to validate Land Surface Temperature (LST) and surface emissivity products with scientific rigor.

The CE312 provides high radiometric accuracy, excellent thermal stability and a fine angular sampling capability that directly supports advanced thermal remote sensing applications. Its multispectral thermal channels and differential measurement principle deliver traceable radiances and brightness temperatures, forming the quantitative foundation for stringent LST product validation. The robotized head adds an essential dimension: automated multi-angle observations. These directional measurements are critical for Temperature–Emissivity Separation (TES) techniques, characterization of surface anisotropy, and the reduction of emissivity-related uncertainties that remain a long-standing challenge in comparing in situ measurements with satellite-derived LST.

Inspired by established ground-based networks such as AERONET for aerosol optical properties and RadCalNet for surface reflectance and BRDF reference measurements, the CE312 installation extends this philosophy to the thermal domain, enabling consistent, traceable multi-angle observations of ground surfaces for enhanced satellite CAL/VAL.

Integrated into CNES’s CAL/VAL strategy, the CE312 now contributes to cross-sensor thermal product intercomparisons, supports the preparation of new missions such as TRISHNA, and provides datasets used in agriculture, hydrology and land–atmosphere energy flux modeling.

La Crau is part of the international TIRCalNet initiative, which aims to establish a harmonized network of ground reference sites for thermal infrared calibration and validation. Within this network, La Crau provides:

  • Well-characterized surface temperature and emissivity measurements for generating reference top-of-atmosphere (TOA) signals.
  • Traceable, stable datasets that help verify and cross-calibrate satellite radiometers.
  • Multi-angle, in situ observations used to reduce LST and emissivity uncertainties and to improve algorithm robustness across missions.

TIRCalNet targets TOA brightness temperature uncertainties on the order of 0.5 K, and the CE312’s radiometric performance and robotic acquisition geometry at La Crau directly support this objective.

Since mid-2023, the CE312 has operated continuously, enhancing the long-term radiometric archive of La Crau, a semi-arid area well known for its stability and suitability for thermal infrared validation. Its directional and multispectral measurements underpin more reliable satellite LST retrievals and strengthen continuity across current and future thermal missions.

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CE376 LiDAR at Izaña (AEMET)

The CE376 LiDAR at Izaña (AEMET)

High above the clouds in the Canary Islands, scientists at the Izaña Observatory (AEMET) are using the CE376 LiDAR to explore the vertical structure of the atmosphere with unprecedented detail. This advanced instrument allows the aerosol science team to monitor aerosols moving across the Atlantic Ocean, providing critical insights into climate, air quality, and weather processes.

The CE376 is a compact dual-wavelength depolarization elastic lidar (532 and 808 nm). Its continuous monitoring capability makes it particularly valuable for atmospheric research. By analyzing data from both channels, the instrument provides detailed information on aerosol properties, allowing our team to capture the vertical distribution and dynamics of aerosols with unmatched precision.

Every day, the CE376 monitors Saharan dust events as they sweep across the Atlantic, revealing how mineral particles interact with clouds and affect radiation. Over time, it has also recorded comprehensive data on various aerosol types, including volcanic sulfate aerosols from the Cumbre Vieja eruption in September 2021, the devastating wildfire event on the island in August 2023, as well as long-range transported, aged wildfire plumes originating from Canadian wildfires during the late spring seasons. These observations have highlighted clear differences in particle size, shape, and optical properties, demonstrating the CE376’s suitability for continuous monitoring and characterization of both the temporal and vertical evolution of atmospheric aerosols.

Fig 1. MODIS VIS channel satellite image showing the Saharan dust over the Canary Islands on 20 August 2020.

Looking ahead, our team is continuously advancing the integration of CE376 lidar data together with sun photometer and in-situ measurements, while appliying sophisticated retrieval techniques such as GRASP (Generalized Retrieval of Aerosol and Surface Properties). This ongoing collaborative synergy is contributing to a more comprehensive understanding of aerosol optical properties and their effects on radiative forcing and regional climate.

More than just an instrument, the CE376 serves as a window into the atmosphere, revealing processes invisible to the naked eye but essential for science, society, and our understanding of a changing climate.

Fig 2. Saharan Air layer reaching the Izaña Observatory (AEMET). Courtesy of Conchy Bayo (AEMET)
Fig3. CE376 Lidar at Izaña Observatory (AEMET)
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NOAA-NASA MD campaign

NASA and NOAA pioneered a shipborne photometer campaign across the Atlantic

In 2023, NASA and NOAA launched a groundbreaking Atlantic campaign, placing an automated, AERONET-compatible sun photometer aboard a research vessel for the first time. The goal was simple but ambitious: collect high-quality aerosol optical depth (AOD) data over ocean regions, long neglected by traditional land-based monitoring networks. By measuring directly from the sea, scientists could fill a critical observational gap and strengthen satellite validation where fixed stations are sparse.

The instrument, a CIMEL CE318‑T, was specially adapted for shipborne deployment. Engineers stabilized it against vessel motion, added protective enclosures to withstand sea spray, and updated the firmware to maintain accurate sun-tracking and sky radiance measurements. Calibrations were aligned with AERONET protocols, ensuring the data matched the rigorous standards of land-based sites.

Adapted CIMEL CE 318‑T photometer installed on the vessel, stabilized against motion and protected from spray

Voyage across the Atlantic

Aboard the RV Marion Dufresne, the photometer captured aerosol characteristics along a route stretching from the tropical Atlantic, across the Intertropical Convergence Zone (ITCZ), and into the mid-latitudes. The ship crossed the ITCZ three times, recording interactions between Saharan dust, marine aerosols, and cloud systems. Over the three-year period, the dataset revealed patterns of episodic dust transport, background sea-spray, and long-range aerosol variability.

The campaign was conducted in close collaboration with the LOA through the AGORA-Lab, which ensured data quality control, calibration traceability, and scientific analysis in coordination with NASA’s AERONET team.

RV Marion Dufresne cruise track across the Atlantic, showing key aerosol sampling regions.

Key insights include:

  • Shipborne AOD retrievals were on par with established AERONET sites, confirming data quality.
  • The measurements provide essential reference points for satellite sensors like PACE and support improved aerosol transport modeling.

Bridging the gap in ocean observations

Oceanic aerosol measurements are scarce but essential for accurate climate modeling and satellite validation. By deploying high-precision, automated photometers on ships, NASA and NOAA created a bridge between sparse ground stations and satellite footprints. This approach allows for continuous monitoring, capturing both episodic events like dust storms and consistent background conditions.

The campaign also sets a template for future maritime aerosol monitoring. Plans include deploying similar instruments on additional vessels, extending geographic coverage, and integrating vertical profiling systems or unmanned aerial platforms. Data are archived in standardized formats and made publicly available, ensuring the scientific community can leverage the measurements for satellite match-ups, climate model validation, and process studies.

By venturing directly into the Atlantic, NASA and NOAA have opened a new chapter in aerosol observation. This initiative not only fills a critical gap in global monitoring but also enhances our understanding of aerosol-cloud-climate interactions in remote ocean regions.

References

  1. Torres, B. et al. 2025. Adaptation of the CIMEL‑318T to shipborne use: 3 years of automated AERONET-compatible aerosol measurements on board the research vessel Marion Dufresne. Atmos. Meas. Tech., 18, 4809‑4838. DOI:10.5194/amt‑18‑4809‑2025.
  2. Torres, B. 2024. Three years of aerosol measurements using an automated photometer on the first long-term AERONET ship site. LOA/Apolo Univ. Lille.
  3. AERONET / Maritime Aerosol Network (MAN) website.
  4. PACE Technical Report Series Vol 11. 2023. PACE Science Data Product Validation Plan. NASA.

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TRANSAMA campaign

TRANSAMA Campaign: Exploring aerosols across the oceans

In April–May 2023, the French research vessel Marion Dufresne II set sail from La Réunion Island toward Barbados on a unique mission: the TRANSAMA campaign (Transit to AMARYLLIS-AMAGAS). As part of the MAP-IO program (Marion Dufresne Atmospheric Program–Indian Ocean), this expedition aimed to deepen our understanding of aerosols — tiny particles suspended in the atmosphere – and their behavior over the open ocean.

Aerosols, whether transported from distant continents or generated locally, play a critical role in cloud formation, sunlight reflection, and climate dynamics. Yet, their behavior over the oceans remains poorly documented due to the logistical challenges of conducting continuous measurements at sea. TRANSAMA was designed to fill this gap by deploying state-of-the-art instrumentation capable of capturing both column-integrated and vertically resolved aerosol data in a fully autonomous, shipborne environment.

To meet this challenge, CIMEL collaborated closely with the Laboratoire d’Optique Atmosphérique (LOA) through their joint research structure, AGORA-Lab, which coordinated and supported all the instrumental installations aboard the ship.

Two CIMEL instruments formed the backbone of this observational campaign. The CE318-T Sun/Sky-Lunar photometer, set up permanently on board the ship since 2021, continuously recorded aerosol optical depth and particle size distribution during daylight hours, while the micro-LiDAR scanned the vertical structure of the atmosphere, revealing the layering of aerosols and their interactions with clouds.

Installed on the deck and carefully adapted for marine conditions, these instruments worked in harmony, providing a detailed picture of the atmosphere above the Atlantic.

Spatio-temporal variability of aerosol properties during the TRANSAMA campaign (21 April–15 May 2023) aboard the RV Marion Dufresne II. Measurements were conducted along the route from La Réunion Island to Barbados. (a) 3D variation of NRB at 532 nm from lidar measurements overlaid on a true-color image of the covered regions. (b) AOD at 440 nm and (c) EAE at 440/870 nm derived from photometer observations, displayed on topographic maps. Photometer data include L1 and L1.5 solar and lunar observations. Red345 pins mark the ports at Le Port (La Réunion), Recife (Brazil), and Bridgetown (Barbados).

Each observation contributed to a growing dataset that bridges the gap between local measurements and global atmospheric models.

Following the success of the 2023 campaign, the set up of a new CE376 lidar aboard Marion Dufresne in the framework of the OBS4CLIM project is scheduled for late October 2025. Once the lidar will be set up on board the vessel, it will record regular mobile measurements during the ship’s rotations from La Réunion island to the French Southern and Antarctic Lands (TAAF). These next voyages will further extend the temporal coverage of aerosol observations and help scientists understand the seasonal variations and long-range transport processes over the Indian and Atlantic Oceans.

CE318-T photometer
CIMEL micro-LiDAR

Key publications

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NASA-ARSET

NASA-ARSET reveals how AERONET contributes to air quality and climate applications

Ground-based networks such as AERONET play a crucial role in atmospheric science and air quality monitoring. During its latest NASA ARSET training titled “Atmospheric Composition Ground Networks Supporting Air Quality,” AERONET was showcased as a global benchmark in providing high-quality aerosol optical data for researchers, air quality managers, and decision-makers.

CIMEL CE318-T photometer enables fully autonomous, standardized, and long-term aerosol monitoring across diverse environments—from megacities to deserts and polar regions. With over 600 stations in 80+ countries, AERONET has become a global reference in satellite validation and atmospheric composition studies.

The ARSET training session reveals:

  • How ground-based observations complement satellite missions
  • The role of AERONET in policy-relevant applications
  • The importance of consistent, open-access data

You can access the training here: NASA ARSET Program

Key benefits of joining NASA-AERONET:

  1. Global data integration: As part of AERONET, CE318-T data integrates into a global network, allowing users to compare and access high-quality, standardized aerosol data worldwide, enhancing research with broader data context.
  2. Real-time data accessibility: AERONET provides near real-time data processing and availability on its online platform, allowing end-users to access and analyze current aerosol measurements efficiently.
  3. High-quality data: CE318-T photometers within AERONET are regularly calibrated at NASA’s calibration facilities, ensuring consistent, reliable, and high-quality data that meet strict scientific standards.
  4. Comprehensive aerosol data products: AERONET processes raw CE318-T measurements to deliver aerosol properties like aerosol optical depth (AOD), particle size distribution, and water vapor content, providing users with valuable insights without needing to process the raw data manually.
  5. Research collaboration opportunities: By participating in AERONET, end-users gain access to a collaborative network of scientists and research institutions globally, fostering opportunities for joint research projects and data sharing.
  6. Data validation for satellite missions: AERONET data is widely used to validate satellite aerosol measurements, allowing end-users to contribute to and benefit from satellite-derived aerosol research and applications in atmospheric studies.
  7. Recognition and credibility: Being part of AERONET enhances the credibility of the data collected, as the network is globally recognized in atmospheric sciences, potentially increasing the impact and visibility of users’ research.
Network of Networks – Calibration Centers/Sites
AERONET network – Calibration Centers/Sites
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New CE710 Raman LiDAR

Pioneering Aerosol Remote Sensing: LOA and CIMEL’s Journey with the CE710 LiDAR for ACTRIS

Keywords: LiDAR, Aerosols, monitoring, remote sensing, ACTRIS, Raman.

November 13th 2024

The Laboratoire d’Optique Atmosphérique (LOA) at the University of Lille, in collaboration with CIMEL, focuses on studying clouds, aerosols, gases, and their interactions with radiation, utilizing advanced remote sensing instrumentation for experiments, observations, and modeling. LOA brings its expertise to ACTRIS as the Quality Assurance and Control Lead, playing a crucial role in maintaining precise and reliable photometric aerosol measurements.

Since 1991, LOA and CIMEL have collaborated to advance and refine photometry techniques for measuring aerosols and water vapor. This collaboration was at the origin of the NASA AERONET planetary network, built with the CIMEL sun/sky/lunar photometers for over three decades. In 2005, building on this success, they extended their cooperation to include aerosol LiDAR technologies. Finally, in 2020, LOA and CIMEL established a joint research laboratory, AGORA-Lab, to develop advanced remote sensing technologies, including Lidars and photometers, and to combine them for cutting-edge performance.

LiDARs provide high-resolution vertical profiles of aerosols and clouds, while photometers offer column-integrated aerosol optical properties. By combining these measurements, calibration, quality control and retrievals are enhanced, leading to better quantification and characterization of aerosols and higher-level data products.

Since 2012, CIMEL and LOA have collaborated on developing the CE710 LiDAR, a high-power, multi-spectral Mie-Raman-Fluorescence LiDAR, spearheading significant advancements in aerosol measurement capabilities. The first version, called LILAS, was set up on the ATOLL platform (Atmospheric Observatory of Lille) and has been part of ACTRIS since 2015.

LOA and CIMEL continuously advance the industrialization and validation of the CE710 LiDAR range, making it a cost-efficient, modular solution that is ACTRIS-ready, meaning it meets all current and future guidelines. This cutting-edge technology provides innovative features that enhance measurement accuracy, operational efficiency, and adaptability to evolving scientific needs.

CE710 LiDAR range: Key features

  • Multi-wavelength emission: 355, 532 and 1064 nm.
  • Up to 15 detection channels: to profile a wide range of atmospheric parameters, including aerosol backscatter, depolarization, fluorescence, water vapor, trace gases, and temperature.
  • Advanced laser technology: Uses diode or flash-lamp pumped Nd:YAG lasers with energy per pulse up to 200 mJ at 355 nm and repetition rate up to 200 Hz.
  • Depolarization capability: Measures linear depolarization ratios at multiple wavelengths to distinguish between spherical and non-spherical particles.
  • Fluorescence detection: Provides additional vertically resolved information to improve aerosol typing.
  • Customizable configurations: The modular design allows adaptation to initial and evolving research objectives.
  • Robust and transportable design: Facilitates installation, inside or outside with optional thermal enclosure.
  • Data Processing: Includes AUSTRAL software for real-time visualization and interpretation of measurement data.

Key benefits of the CE710 LiDARs for the ACTRIS community

  • Enhanced data quality: The CE710 meets all the requirements of the stringent ACTRIS Quality Assurance guidelines, that ensure high measurement precision and reliability and are a prerequisite for data certification by ACTRIS.
  • Comprehensive aerosol profiling: The multi-channel design allows detailed characterization of aerosol physical and chemical properties, providing valuable inputs for atmospheric models.
  • Integrated calibration tools: The built-in remote control and calibration functions enable operators to consistently perform standardized quality control operations over time.
  • Advanced analysis capabilities: The AUSTRAL software offers real-time data processing and visualization, enabling quick assessment of atmospheric conditions and facilitating advanced research and collaborative projects.
  • Future-Proof Design: The modular architecture supports future upgrades, allowing the system to adapt to evolving scientific requirements and technological advancements.

For more information on the CE710 LiDAR range, click here!

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GAWPFR WMO reference

New AOD tracking technique by ESA with AERONET and the GAWPFR WMO reference

Keywords : Aerosols, Atmosphere, Sun/Sky/Lunar photometer, Meteorology

The World Meteorological Organization (WMO) has recognised the Word Optical Depth Research and Calibration Center (WORCC) as the primary reference center for Aerosol Optical Depth measurements. The WORCC is a section within the World Radiation Center at the Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC), located in Davos, Switzerland.

With its new QA4EO project, European Space Agency (ESA) wishes to obtain homogeneous results between the various passive monitoring networks of passive remote sensing of aerosol optical properties, presents in Davos and in France at the Observatoire de Haute Provence (OHP).

Consequently, a precision filter radiometer (PFR) travelling standard was installed at the European calibration site of AERONET to supply continuous traceability of aerosol optical depth measurements to the World reference maintained at Davos through a PFR Triad.

The precision filter radiometer was installed in July 2020 at the Observatoire de Haute Provence (OHP) on a solar tracker provided by the Laboratoire d’Observation Atmosphérique (LOA) next to our 4 sun photometers (CE318-T).

OHP’s platform, with four CIMEL Sun/Sky/Lunar photometers CE318-T and the PFR traveling (at the right of the picture).

The measurements of spectral solar irradiance during clear sky periods are used to retrieve AOD from our photometers with AERONET calibration and the PFR.

You can follow the comparison between these two instruments in real time on this web page. This real-time analysis allows for continuous monitoring and quality control of the measurements provided by these two devices.

Real-time monitoring of the measurement analysis of the two instruments on 24 March 2021 – Source: https://www.pmodwrc.ch/en/world-radiation-center-2/worcc/gaw-pfr/ohp/

After 6 months of comparison (August 2020 to January 2021) between the two networks, results have been very promising with an Aerosol Optical Depth difference of less than 0.01, corresponding perfectly to the WMO criteria for AOD traceability for 3 of its 4 channels. This shows that the results provided by CIMEL CE318-T photometers are in line with the WMO expectations and that CIMEL photometers may be used as an instrument of reference for other research projects.

Other projects are in parallel with this one such as the 19ENV04 project funded by EURAMET and the European Commission to extend the traceability of international unit systems through the characterization and calibration of our Sun/Sky/Lunar photometers from these networks (See more information here).

This collaboration between research institutes and the European metrology community will establish a consistent framework providing calibrations of our Sun/Sky/Lunar photometers with traceability to the SI as well as comprehensive uncertainty budgets that will be a necessary part of the data provided to the users and actors of these networks.

References:
Kazadzis, S., Kouremeti, N., Nyeki, S., Gröbner, J., and Wehrli, C.: The World Optical Depth Research and Calibration Center (WORCC) quality assurance and quality control of GAW-PFR AOD measurements, Geosci. Instrum. Method. Data Syst., 7, 39-53, https://doi.org/10.5194/gi-7-39-2018, 2018.