AS1.15 | The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) ready for Launch
The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) ready for Launch
Convener: Thorsten Fehr | Co-conveners: Takuji Kubota, Robin Hogan, Hajime Okamoto
| Thu, 18 Apr, 10:45–12:30 (CEST)
Room 0.11/12
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
Hall X5
Posters virtual
| Attendance Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
vHall X5
Orals |
Thu, 10:45
Thu, 16:15
Thu, 14:00
The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) satellite mission aims to improve our understanding of cloud-aerosol-radiation interactions and Earth radiation budget, such they can be modelled with better reliability in climate and numerical weather prediction models. To achieve this objective, EarthCARE will measure the three-dimensional structure of clouds, precipitation and aerosols, together with collocated observations of solar and terrestrial radiation. EarthCARE will provide unique co-registered observations from a suite of four instruments located on a common platform: (1) ATmospheric LIDar (ATLID), Cloud Profiling Radar (CPR), Multi- Spectral Imager (MSI) and BroadBand Radiometer (BBR). EarthCARE global observations include vertical profiles of natural and anthropogenic aerosols, the vertical contribution of ice and liquid water content, the cloud mesoscale distribution, precipitation microphysics, estimates of particle size, convective vertical air motions, as well as of atmospheric radiative heating and cooling profiles.The launch of this joint European-Japanese mission is planned by mid-2024, providing unique data continuing the heritage measurements by CloudSat, CALIPSO and Aeolus, and bridging towards future missions such as NASA's Atmosphere Observing System mission (AOS) or Aeolus-2.

Orals: Thu, 18 Apr | Room 0.11/12

On-site presentation
Timon Hummel, Dirk Bernaerts, Jonas von Bismarck, Patrick Deghaye, Michael Eisinger, Thorsten Fehr, Björn Frommknecht, Robert Koopman, Stephanie Rusli, Vasileios Tzallas, and Kotska Wallace

The Earth Cloud Aerosol and Radiation Explorer (EarthCARE) is a satellite mission carried out by the European Space Agency (ESA) in collaboration with the Japan Aerospace Exploration Agency (JAXA) to measure global profiles of aerosol, cloud and precipitation properties along with radiative fluxes and derived warming rates, with the goal of advancing our understanding of cloud-aerosol and radiation interactions and the Earth's radiative budget.

In order to fulfil its objectives, the EarthCARE mission will collect co-registered observations from a suite of four instruments located on a common platform. The optical payload encompasses the three ESA instruments, namely an ATmospheric LIDar (ATLID), a Multi-Spectral Imager (MSI) and a BroadBand Radiometer (BBR). The fourth instrument, provided by JAXA, is the Cloud Profiling Radar (CPR). The two active instruments (ATLID and CPR) will provide vertical profiles of the atmosphere along the satellite nadir path. The two passive instruments (BBR and MSI) will provide scene context information to support the active instruments data interpretation.

The presentation will provide an update on the status of EarthCARE processors and products prior to launch, focusing on ESA's ground science data processing chain, which includes the production of calibrated instrumental data (Level 1 data products) and retrieved geophysical data (Level 2 data products). Further, we will introduce the Data Innovation and Science Cluster (DISC) for the mission exploitation phase (E2). The DISC brings together several groups of instrument and product experts in one cluster to establish a comprehensive product quality assurance framework, including activities related to product algorithm evolution, data assimilation, calibration, validation support, and performance monitoring of ESA's EarthCARE products.

How to cite: Hummel, T., Bernaerts, D., von Bismarck, J., Deghaye, P., Eisinger, M., Fehr, T., Frommknecht, B., Koopman, R., Rusli, S., Tzallas, V., and Wallace, K.: EarthCARE Processors and Products: Status Update and Outlook, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9240,, 2024.

On-site presentation
Gerd-Jan van Zadelhoff and David Donovan and the CARDINAL team

The interactions between clouds, aerosols, and solar and terrestrial radiation play  key roles in the Earth’s Climate. Despite a long history of satellite observations, further high-quality novel observations are needed for atmospheric model evaluation and process studies. It has been recognized that true height-resolved global observations of cloud and aerosol properties are essential for making progress. EarthCARE is an upcoming ESA/JAXA mission scheduled to fly in 2024, focusing on providing these observations.

Operating in a sun-synchronous orbit at 393 km altitude with a descending node at 14:00, EarthCARE's payload comprises two innovative active (Atmospheric UV High spectral resolution Lidar - ATLID and Cloud Profiling Doppler Radar - CPR provided by Japan) and two passive (Multi-Spectral Imager - MSI and Broad-Band Radiometer - BBR) instruments. Using these instruments, EarthCARE will provide global profiles of clouds, aerosols, and precipitation properties, along with co-located radiative TOA flux measurements. These atmospheric microphysical properties and associated radiative fluxes will be used to evaluate the representation of aerosols, clouds, and precipitation in weather forecast and climate models, contributing to the improvement of parameterization schemes. 

The ESA scientific retrieval processors fully exploit the synergy of these observations. EarthCARE will provide twenty-five science (Level 2) products. These products include nadir profiles of cloud, aerosol and precipitation properties along with constructed three-dimensional cloud-aerosol-precipitation domains and associated derived radiative properties, such as heating rates. The final L2 processor compares the forward modeled top-of-atmosphere broad-band radiances and fluxes based on the constructed 3D atmospheric scenes with those measured by the BBR in order to assess and improve the quantitative understanding of the role of clouds and aerosols in the Earth's radiation budget.

This presentation will provide an overview of the EarthCARE mission, its data processors and scientific products.

How to cite: van Zadelhoff, G.-J. and Donovan, D. and the CARDINAL team: Illuminating the Interplay between Clouds, Aerosols, and Radiation: Introducing the ESA EarthCARE L2 processing chain., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9113,, 2024.

On-site presentation
Shannon Mason, Robin Hogan, Alessio Bozzo, and Ben Courtier

EarthCARE will continue the record of spaceborne radar, lidar, and radiometric measurements that was begun in 2006 by CloudSat, CALIPSO, MODIS and CERES within the A-Train of satellites. EarthCARE’s multispectral imager (MSI), three-view broadband radiometer (BBR), Doppler-capable cloud profiling radar (CPR) and high-spectral resolution atmospheric lidar (ATLID) provide some advances over the instruments within the A-Train, and the single platform will improve the coregistration of synergistic measurements. Ultimately, the greatest novelty of the EarthCARE mission may arise from its highly coordinated L2 production models, which cover products ranging from single-instrument detection, target classification, and retrieval products, to synergistic retrievals, radiative transfer modelling, and finally top-of-atmosphere radiative closure assessment. Central to the ESA L2 production model is the synergistic (ATLID-CPR-MSI) “best estimate” retrieval of all clouds, aerosols and precipitation in the atmosphere, called ACM-CAP.

ACM-CAP is based on the CAPTIVATE optimal estimation retrieval algorithm, which includes sophisticated and efficient representations of hydrometeor fallspeeds to constrain ice particle density and raindrop size, ice particle scattering properties, radar and lidar multiple scattering, passive solar, thermal and microwave radiances, and the HETEAC model for aerosol properties. To test our retrieval and enhance scientific continuity between EarthCARE and the A-Train, we have developed an equivalent CloudSat-CALIPSO-MODIS retrieval product, called CCM-CAP, based on the same retrieval algorithm. 

In this talk we provide an overview of the ACM-CAP product, its capabilities and its place within the EarthCARE ESA production model. Using CCM-CAP, we present case studies and evaluation of the retrieved cloud and precipitation properties, and discuss how the challenges for unified retrievals in complex and layered scenes will inform the regimes of interest for validation and evaluation once EarthCARE data are available.

How to cite: Mason, S., Hogan, R., Bozzo, A., and Courtier, B.: Synergistic and unified retrieval of clouds, aerosols and precipitation from EarthCARE and the A-Train: the ACM-CAP and CCM-CAP products, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8811,, 2024.

Virtual presentation
Tomoaki Nishizawa, Rei Kudo, Eiji Oikawa, Akiko Higurashi, Yoshitaka Jin, Kaori Sato, and Hajime Okamoto

We have developed JAXA L2 algorithm to retrieve aerosol and cloud optical properties using data of 355nm high spectral resolution lidar (HSRL) with depolarization measurement function “ATLID” onboard EarthCARE satellite, to determine the global distribution of aerosols and clouds and to better understand cloud-aerosol interactions and their climate impacts. Using the three channel data of the ATLID, the developed algorithm estimates (1) extinction coefficient, backscatter coefficient and depolarization ratio of particles (aerosols and clouds) without assuming a particle lidar ratio, (2) identifies molecule-rich, aerosol-rich, or cloud-rich slab layers, (3) classifies particle type (e.g., dust and maritime), (4) retrieves planetary boundary layer height, and (5) estimates extinction coefficients for several main aerosol components such as dust, sea-salt, carbonaceous, and water-soluble aerosols using difference in depolarization and light absorption properties of the aerosol components. Furthermore, we have developed aerosol retrieval algorithm using both the ATLID and multi-spectral imager “MSI”. This algorithm retrieves vertically mean mode-radii for dust and fine-mode aerosols as well as the extinction coefficients for the four aerosol components using the three channels of the ATLID and radiances at 670nm and 865nm of MSI. The algorithms described above were developed based on our developed algorithm for the CALIOP and MODIS measurements. In the presentation, the overview of the algorithms and their performance will be described. In addition, related studies will be presented.

How to cite: Nishizawa, T., Kudo, R., Oikawa, E., Higurashi, A., Jin, Y., Sato, K., and Okamoto, H.: Development of JAXA L2 algorithm to retrieve aerosol and cloud properties using ATLID and MSI, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22410,, 2024.

On-site presentation
Woosub Roh and Masaki Satoh

EarthCARE, equipped with a suite of passive and active sensors, including Cloud Profiling Radar (CPR), Atmospheric LIDar (ATLID), Multi-Spectral Imager (MSI), and Broad Band Radiometer (BBR), is designed for comprehensive studies of clouds, aerosols, precipitation, and their radiation impact. The CPR's Doppler capability is crucial for assessing the terminal velocity of rain and ice particles and understanding convective motions.

Global storm-resolving models (GSRMs, Satoh et al. 2019; Stevens et al. 2019) have been used to generate detailed simulations of mesoscale convective systems using a kilometre-scale horizontal grid. New observations, such as the Doppler velocity from EarthCARE, will provide new insights into the evaluation and improvement of a GSRM.

Moreover, the utilization of satellite simulators — comprehensive radiative transfer models designed to simulate satellite signals using outputs from atmospheric models like GSRMs — plays a crucial role in this process. These simulators are integral for assessing, enhancing, and aligning numerical models with satellite observation data.

This study investigates EarthCARE's potential to enhance GSRM evaluations and improvements using a satellite simulator. We also introduce our collaboration with a satellite remote sensing group in developing retrieval algorithms.

How to cite: Roh, W. and Satoh, M.: EarthCARE's Potential to Evaluate a Global Storm-Resolving Model Using a Satellite Simulator, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9144,, 2024.

On-site presentation
Marie-Laure Roussel, Hélène Chepfer, Olivier Chomette, and Marine Bonazzola

The Aeolus mission,  conducted by the European Space Agency (ESA), relies on lidar technology to measure global wind profiles and observe Earth's atmosphere, and in particular clouds that will be the subject of special attention with the incoming Earth Care mission. In future climate predictions generated through climate models, clouds represent the greatest source of uncertainty. Therefore, it is crucial to study them, especially within the atmospheric column, as their vertical distribution has a radiative impact which is poorly known. Active lidar remote sensing technology onboard satellites is a valuable way of conducting measurements accross the atmosphere. However, cloud comparison between observational data and models is challenging due to differences in their definitions. To address this issue, a simulator is employed to model cloud-specific features as they would appear to a given instrument if it were flying over the modeled Earth.

This research initiative enhances the functionalities of the existing CFMIP Observation Simulator Package (COSP) (Bodas Salcedo, 2011). Our developments rest on the advancements achieved in adapting COSP for various satellite instruments in the past (Chepfer, 2006 & 2008) and its improvements over the years (Swales, 2018 - Bonazzola, 2023). The ongoing work focuses on refining the specifities of the current simulator to meet the unique requirements of the lidar of the Aeolus satellite and preparing thoses of ATLID onboard Earth Care satellite.

The success of this development is optimistic for the future creation of the simulator of the lidar of the Earth Care satellite that may be launched this year, showing the adaptability and versatility of this tool. Ultimately, these advancements contribute to the broader scientific community by providing a sophisticated tool for the analysis of satellite data and the validation of model predictions across various satellite missions (Cesana, 2013).

How to cite: Roussel, M.-L., Chepfer, H., Chomette, O., and Bonazzola, M.: Advancements in COSP Lidar Simulator Development for Aeolus Satellite Instrument and Future Applications for Earth Care, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18417,, 2024.

On-site presentation
Florian Ewald, Silke Groß, Martin Wirth, and Julien Delanoe͏̈

Radar and lidar are valuable active remote sensing techniques to assess global ice cloud properties from space. Recent global climate model studies are increasingly relying on ice cloud products obtained from the synergy of the radar and lidar satellites in the A-Train constellation. For the first time, the upcoming ESA/JAXA satellite mission EarthCARE will acquire radar-lidar measurements from a single platform, ensuring the continuity of vertical resolved ice cloud products on a global scale. Due to additional and higher resolved measurements and a more comprehensive retrieval framework, a seamless transition from A-Train products cannot be taken for granted.  In this light and with the imminent launch of EarthCARE, it is now crucial to establish a validation strategy for the EarthCARE products using airborne measurements.

During the A-Train era, we learned numerous lessons and gained experience with coordinated aircraft and satellite underpasses which we performed during several airborne campaigns. During these exercises, the German research aircraft HALO was equipped with a EarthCARE-like payload consisting of a high spectral resolution lidar (HSRL) system at 532 nm, a high-power cloud radar at 35 GHz, a microwave radiometer package, and passive radiation measurements. Coordinated flights were performed with other airborne platforms carrying instruments at different wavelengths (DLR Falcon, Safire Falcon and ATR) or for validation with in-situ measurements (FAAM BAe-146) as well as below the A-Train satellite tracks.

In this presentation, we will give an overview of our lessons learned and how they are guiding our airborne validation strategy. Going along with the commissioning of EarthCARE, we will employ HALO with its remote sensing payload in the PERCUSION campaign later this year. Based from multiple locations in the tropical Atlantic (Cape Verde and Barbados) and Europe (Oberpfaffenhofen), underflights of EarthCARE will be performed. The comparison with the dataset acquired during A-Train underpasses will allow us to determine if derived cloud products can be directly compared or if conversions are necessary. By sharing our knowledge and plans with the wider community, we hope to foster helpful discussions to consolidate our airborne validation strategy for EarthCARE.

How to cite: Ewald, F., Groß, S., Wirth, M., and Delanoe͏̈, J.: How lessons learned during previous validation campaigns are guiding our airborne validation of EarthCARE , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12971,, 2024.

On-site presentation
Ivona Cetinić, Kirk Knobelspiesse, Brian Cairns, and Monserrat Piñol Solé

NASA’s Plankton, Aerosol, Clouds and ocean Ecosystems (PACE) Mission, scheduled to be launched in early 2024, will produce a variety of ocean color, aerosol, cloud and land surface data products from its three sensors. Some of these products will be created with established ‘heritage’ algorithms, and others are new, representing recent algorithm development and the unique measurement capability of the PACE sensors. A crucial part of the validation activities is the PACE Postlaunch Airborne eXperiment (PACE-PAX), that is planned to occur in September of 2024. This dedicated field campaign, due to its platform and instrumental setup, offers an opportunity to support not only PACE, but the EarthCARE mission as well, opening opportunities for validation, new collaborations, and development of new algorithms for both Earth science missions.

How to cite: Cetinić, I., Knobelspiesse, K., Cairns, B., and Piñol Solé, M.: PACE-PAX validation campaign – validating PACE and supporting Earthcare, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20116,, 2024.

On-site presentation
Lukas Pfitzenmaier, Nils Risse, Pavlos Kollias, Bernat Puigdomenech Treserras, and Imke Schirmacher

The value of permanent, multi-sensor surface-based observatories that collect continuous long-term observations for satellite L2 data products has grown significantly over the last 10-15 years. Examples of such established surface-based networks include the Aerosol, Clouds, and Trace Gases Research Infrastructure (ACTRIS) network, the US Department of Energy Atmospheric Radiation Measurements (ARM) observatories, and the recently established 94-GHz Miniature Network for EarthCARE Reference Measurements (FRM4Radar).

The core of the work presented is the use of the developed transformation of suborbital to orbital radar data by Orbital-Radar. This simple L1 transformational operator converts L1 suborbital (ground-based or airborne) measurements to the EarthCARE Cloud Profiling Radar (CPR) L1 observations. The transformational operator ensures that the orbital to suborbital comparison accounts for differences in the sampling geometry, measurement uncertainty, and instrument sensitivity and simulates the impact of the surface echo. Furthermore, the operator simulates the EarthCARE characteristic reflectivity and Doppler velocity errors.

Applying such a tool to long-time data sets allows to generate the optimal foundation for a statistical analysis of the EarthCARE CPR performance. Hence, the optimal sampling for CPR and ground-based data can be estimated, and the CPR detection of clouds and precipitation processes near the ground can be analyzed and evaluated. In addition, it shows how critical ground-based networks are and that they play an essential role in evaluating satellite measurements and products. Tools like Orbital-Radar may help evaluate future CPR satellite missions, expanding the L1 transformational operator to other spaceborne radar systems.

How to cite: Pfitzenmaier, L., Risse, N., Kollias, P., Puigdomenech Treserras, B., and Schirmacher, I.: Using synthetic EarthCARE Cloud Profiling Radar data to develop validation methodologies for ground-based cloud radar sites, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15182,, 2024.

On-site presentation
Zhipeng Qu, Jason Cole, Howard Barker, Meriem Kacimi, Shannon Mason, Robin Hogan, and Ben Courtier

The EarthCARE mission will perform continuous radiative closure assessment utilizing both 1D and 3D broadband (BB) radiative transfer (RT) models. The radiance and flux calculations from these models will be compared to observations obtained through EarthCARE's Broadband Radiometer (BBR). The inputs for the RT models will be derived from synergistic retrievals of cloud and aerosol properties, facilitated by the Clouds, Aerosol and Precipitation from Multiple Instruments using a Variational Technique (CAPTIVATE) algorithm. In preparation for the EarthCARE launch, this study involves the application of CAPTIVATE to A-Train data, with the resultant cloud, aerosol, and precipitation properties serving as inputs for the RT models. The outcomes of these models will be utilized in a radiative closure assessment, incorporating measurements from the Clouds and the Earth's Radiant Energy System (CERES). The analyses center on discerning differences between 1D and 3D RT calculations, as well as differences between RT calculations and measurements obtained from the CERES.

How to cite: Qu, Z., Cole, J., Barker, H., Kacimi, M., Mason, S., Hogan, R., and Courtier, B.: Radiative closure assessment using A-Train satellite data for the EarthCARE mission, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13604,, 2024.

Posters on site: Thu, 18 Apr, 16:15–18:00 | Hall X5

Display time: Thu, 18 Apr 14:00–Thu, 18 Apr 18:00
Thorsten Fehr, Dirk Bernaerts, Jonas von Bismarck, Patrick Deghaye, Michael Eisinger, Björn Frommknecht, Timon Hummel, Robert Koopman, Stephanie Rusli, and Kotska Wallace

The influence of clouds on incoming solar and reflected thermal radiation remains the largest contribution to the overall uncertainty in climate feedbacks due to the diverse cloud formation processes. Furthermore, climate models still show deficiencies in correctly representing aerosol-cloud interactions and precipitation patterns limiting the overall confidence in climate predictions.

Global observations of vertical cloud ice and liquid water profiles with simultaneous and collocated solar and thermal flux observation will provide crucial data to address this uncertainty. Furthermore, collocated global observation of vertical aerosol profiles and types are required to address their direct effects and indirect aerosol-cloud-interaction effects.

In response to these needs, the European Space Agency (ESA), in cooperation with the Japan Aerospace Exploration Agency (JAXA), plans to launch the Earth Cloud, Aerosol and Radiation Explorer Mission, EarthCARE – ESA’s Cloud and Aerosol mission – in May 2024.

The two active instruments embarked on the satellite, a cloud-aerosol lidar (ATLID) and a cloud Doppler radar (CPR), together with the passive multispectral imager (MSI) and broad-band radiometer (BBR), will provide synergistically derived vertical profiles of cloud ice and liquid water, aerosol type, precipitation, as well as heating rates, solar and thermal top-of-atmosphere radiances with the objective to reconstruct top-of-the-atmosphere short- and longwave fluxes at an accuracy of 10 Wm-2 on a 10 km×10 km scene. The mission aims to significantly improve our understanding in the cloud and aerosol radiative feedback mechanisms, and their representation in climate and weather forecasting models.

The presentation will provide an up-to-date overview of the mission and science status weeks before the planned EarthCARE launch on a Falcon-9 rocket beginning of May 2024 from Vandenberg, USA. It will cover the mission’s science objectives, main performances of the three ESA instruments, expected science advances and foreseen validation activities. A detailed presentation on the data products, ground processing and data quality assurance will be provided by T. Hummel et al. at EGU24.

How to cite: Fehr, T., Bernaerts, D., von Bismarck, J., Deghaye, P., Eisinger, M., Frommknecht, B., Hummel, T., Koopman, R., Rusli, S., and Wallace, K.: EarthCARE, ESA’s Cloud and Aerosol Mission, Preparing for Launch, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8607,, 2024.

Takuji Kubota and Hajime Okamoto

Earth Clouds, Aerosols and Radiation Explorer (EarthCARE) mission (Illingworth et al. 2015) is designed to produce the maximum synergetic collaboration of European and Japanese science teams (Wehr et al. 2023, Eisinger et al. 2024). The EarthCARE products will be developed and distributed from both JAXA and ESA. Continuous exchanges of information have been conducted between Japan and Europe through the Joint Algorithm Development Endeavor (JADE). CPR, ATLID and MSI Level-2 provide cloud mask, cloud phase and cloud microphysics (such as cloud effective radius, liquid water content, optical depth, etc) for the respective sensor products, together with the synergy products by using the combination of the sensors. Further, the CPR provides the Doppler velocity measurement (which gives the vertical information of the in-cloud velocity), and precipitation products. ATLID Level-2 includes aerosol flagging, aerosol component type (such as dust, black carbon, sea salt and water soluble), as well as the aerosol optical properties including aerosol extinction. The cloud and aerosol products will be used to derive the radiative flux at shortwave and longwave, whose consistency with the BBR will be checked to produce the final radiation product by 4-sensors.

EarthCARE synthetic data using a global storm-resolving (NICAM) and Joint-Simulator (Joint Simulator for Satellite Sensors) have been developed in Japan and used in the JAXA L2 algorithm developments (Roh et al. 2023).

Validation activities are necessary to distribute the scientific products whose quality and reliability are assured. The JAXA is planning the validation activities by utilization of the existing observation network, campaign observation, and cross comparison with other satellite data.

Furthermore, a wide range of application research activities will be planned to achieve the mission objectives. EarthCARE observation data will contribute to understanding cloud, aerosol, and radiation processes, evaluations and improvements of climate models and numerical weather prediction (NWP) models, and atmospheric quality monitoring. JAXA is conducting joint-works with universities and research institutes. The Intergovernmental Panel on Climate Change (IPCC) report published in August 2021, “Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the IPCC”, summarizes that the cloud feedback remains the largest contribution to overall uncertainty, and contributions to mitigate the uncertainty can be expected by new insights by the EarthCARE observations.

This presentation will introduce JAXA Level 2, Validation and Applications Preparation for the EarthCARE mission.

How to cite: Kubota, T. and Okamoto, H.: JAXA Level-2 Algorithms, Validations and Applications Preparation for the EarthCARE, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4236,, 2024.

David Donovan, Gerd-Jan van Zadelhoff, and Ping Wang

ATLID (Atmospheric Lidar) is the lidar to be embarked on the Earth Clouds and Radiation Explorer (EarthCARE) mission. EarthCARE is a joint ESA-JAXA mission and will embark a cloud/aerosol lidar (ATLID), a cloud-profiling Radar (CPR) a multispectral cloud/aerosol imager (MSI) and a three—view broad-band radiometer (BBR). ATLID is a 355nm high-spectral-resolution, polarization sensitive lidar.

The accurate retrieval of aerosol and cloud properties from space-based lidar is a challenging endeavor, even when the extra information provided by an HSRL system is exploited. The generally low signal-to-noise (SNR) ratios involved coupled with the need to respect the structure of the aerosol and cloud fields being sensed are particular challenges.

Over the past several years, cloud/aerosol algorithms have been developed for ATLID that have focused on the challenge of making accurate retrievals of cloud and aerosol extinction and backscatter specifically addressing the low SNR nature of the lidar signals and the need for intelligent binning/averaging of the data. Two of these ATLID processors are A-FM (ATLID featuremask) and A-PRO (ATLID profile processor). A-FM uses techniques adapated from the field of image processing to detect the presence of targets at high resolution while A-PRO (using A-FM as input) preforms a multi-scale optimal-estimation technique in order to retrieve both aerosol and cloud extinction and backscatter profiles.

Adaptations of the A-FM and A-PRO processors have been developed for Aeolus (called AEL-FM and AEL-PRO, respectively) and have been introduced into the Aeolus L2a operational processor. In this presentation A-FM and A-PRO will be described. Results based on simulated data for A-FM and A-PRO and results using AEL-FM and AEL-PRO using Aeolus observations will be presented and discussed.


How to cite: Donovan, D., van Zadelhoff, G.-J., and Wang, P.: The EarthCARE ATLID profile processors, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16225,, 2024.

Kamil Mroz, Bernat Puidgomènech Treserras, Alessandro Battaglia, and Pavlos Kollias

This presentation delves into the C-CLD processor and its output product, both named the same, developed for the EarthCARE mission. The C-CLD processor has been designed to extract detailed microphysical properties of clouds and precipitation from the EarthCARE Cloud Profiling Radar data. The algorithm introduces a significant advancement by incorporating Doppler velocity information for the first time in space-borne radar retrievals. Our approach integrates an optimal estimation method to deduce vertical profiles of hydrometeor water content and particle characteristic size, employing reflectivity, mean Doppler velocity measurements, and path-integrated attenuation. The algorithm's robustness is further amplified by an ensemble-based method in the ice regions, ensuring both accuracy and consistency in the forward model relations.

Emphasizing the algorithm's advancements, we present a comprehensive overview of its theoretical basis and development. This includes the validation process, performance sensitivity analysis and quantification of the information content. The presentation will demonstrate the retrieval efficacy in diverse atmospheric conditions, ranging from warm to cold rain and snow.

In addition to algorithmic developments, our research also emphasizes the importance of iterative testing and refinement. Our approach combines model simulations with actual campaign datasets, which include both in-situ and remote sensing measurements, to validate and refine our methods. The rigorous analysis of data from campaigns like CADDIWA or IMPACTS, provided insights that allowed us to improve the C-CLD algorithm, ensuring its robustness and improving the reliability of its retrievals.

How to cite: Mroz, K., Puidgomènech Treserras, B., Battaglia, A., and Kollias, P.: Cloud and Precipitation Microphysical Retrievals from the EarthCARE Cloud Profiling Radar: The C-CLD Product, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17575,, 2024.

Hajime Okamoto, Kaori Sato, Tomoaki Nishizawa, and Hiroaki Horie

JAXA L2-algorithms for cloud properties and vertical velocity were developed for the EarthCARE mission. CPR will be the first 94GHz Doppler cloud radar in space and ATLID is the 355nm-high spectral resolution lidar that can provide backscattering, extinction and depolarization ratio. The JAXA L2 standard cloud products will be derived by using (1) CPR-only algorithms without Doppler velocity, (2) CPR and ATLID algorithms and (3) CPR. ATLID and MSI algorithms. The JAXA L2 research product will be produced by using Doppler velocity (Vd) from CPR in addition to above. The products include cloud mask, cloud particle type, cloud particle categories, terminal velocity and vertical air motion. The L2 algorithms correspond to the extended version to those for CloudSat, CALIPSO (Hagihara et al., 2010 for cloud mask, Yoshida et al., 2010 and Kikuchi et al., 2017 for cloud particle type and Okamoto et al., 2010, Sato and Okamoto 2011 for cloud microphysics) and the latter has been distributed as JAXA EarthCARE A-train products. Vd may be affected by aliasing and the correction algorithm was developed. After the correction, Vd is effective to discriminate clouds and precipitation in cloud particle type products. It is also effective to specify the upward motion in convections. Cloud particle type algorithms for CPR use Vd and Ze for the better discrimination of clouds and precipitation. Two-dimensional diagram of lidar ratio and depolarization ratio from ATLID enables to retrieve ice particle categories (Okamoto et al., 2019, 2020, Sato and Okamoto 2023). The knowledge of particle categories reduce the uncertainties in the retrieved microphysics. Recently developed physical model (Sato et al., 2018) and vectorized physical model (Sato et al., 2019) were implemented into the algorithms to account multiple scattering contribution to the signals.

Synergetic ground-based observation system has been constructed in NICT Koganei, Tokyo. The ground-based system consists of 94GHz high-sensitivity-cloud radar (HG-SPIDER) and electric scanning cloud radar (ES-SPIDER), Multi-Field-of-view Multiple Scattering Polarization Lidar (Okamoto et al., 2016, Nishizawa et al., 2021), high spectral resolution lidar (Jin et al., 2020), direct-detection Doppler lidar (Ishii et al., 2022), coherent Doppler lidar (Iwai et al., 2013) and wind profiler. Cloud mask, particle type, cloud particle category, cloud microphysics, terminal velocity and vertical motion are retrieved by the system and can be used to evaluate L2 products.

How to cite: Okamoto, H., Sato, K., Nishizawa, T., and Horie, H.: Development of JAXA L2 algorithms to retrieve cloud properties and vertical velocity for the EarthCARE mission, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20244,, 2024.

Kaori Sato and Hajime Okamoto

Improved representation of ice-phase processes in numerical models necessitates an enhanced understanding of ice-particle microphysics/radiative properties and their respective formation conditions. The EarthCARE JAXA L2 standard/research algorithms for clouds, precipitation and vertical motions aims at providing more detailed information of cloud particle categories and associated cloud microphysics/radiative properties from ATLID-CPR-MSI synergy. In particular, measurements from CPR Doppler and ATLID are expected to enable more comprehensive exploration of the relation between different cloud particle categories and the dynamical conditions. Based on complimentary information from long-term A-train data, the cloud particle category classification methodology planned for EarthCARE is tested and a new dataset has been developed. With this dataset, the geographical dependence of the occurrence of different ice cloud particle habit category and their properties that will be further investigated in detail from EarthCARE observations are discussed. Activities related to JAXA L2 validations from EU-Japan collaboration are developing new ways of combining ground-based active sensors and detailed surface observation of snow and rain to improve the quantification of precipitation and particle type retrievals. These studies would be valuable for further assessing the physical processes associated with cloud-precipitation formation from the EarthCARE mission.

How to cite: Sato, K. and Okamoto, H.: EarthCARE mission for global height-resolved cloud particle categories and vertical motion, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20108,, 2024.

Almudena Velazquez Blazquez, Carlos Domenech, Edward Baudrez, Nicolas Clerbaux, and Carla Salas Molar

The Broad-Band Radiometer (BBR) instrument on the EarthCARE satellite will provide accurate outgoing solar and thermal radiances at the Top of the Atmosphere (TOA) obtained in an along track configuration at three fixed viewing directions (nadir, fore and aft).

The operational BMA-FLX product on top-of-atmosphere radiative fluxes, is based on a radiance-to-flux conversion algorithm mainly fed by the unfiltered broad-band radiances, obtained in the BM-RAD product, auxiliary data from EarthCARE L2 cloud products and modelled geophysical databases. The conversion algorithm models the angular distribution of the reflected solar radiation and thermal radiation emitted by the Earth-Atmosphere system, and returns geometry independent flux estimates to be used for the radiative closure assessment of the Mission.

Different methodologies are employed for the solar and thermal BBR ADMs. Models for SW radiances are created for different scene types and constructed from Clouds and the Earth’s Radiant Energy System (CERES) data using a feed-forward back-propagation artificial neural network (ANN) technique. The LW angular models are derived through multiple regressions on brightness temperatures and brightness temperature differences of the multispectral imager (MSI) 10.8 µm and 12 µm channels, and corresponding LW fluxes obtained by using a large database of LibRadtran and SBDART radiative transfer simulations.

Both retrieval algorithms exploit the multi-viewing capability of the BBR by applying the radiance to flux conversion algorithms to each of the BBR views, which have been previously collocated at a reference level in order to minimize parallax effects. The reference height where the three BBR measurements are co-registered corresponds to the height where most reflection or emission takes place and depends on the spectral regime. LW observations are co-registered at the cloud top height while SW reference height is instead selected by minimizing the flux differences between nadir, fore and aft fluxes. The derived fluxes from the collocated views are then combined into a single flux value at the selected reference level.

Verification of the algorithms has been carried out using the 3 test scenes developed by the EarthCARE team using the Environment Canada and Climate Change’s Global Environmental Multiscale model (GEM). The BBR solar and thermal flux retrieval algorithms have been successfully employed to retrieve radiative fluxes over the 3 test scenes. Comparisons with the true fluxes from the GEM model provide RMSE < 5 W/m² for the LW fluxes and < 15 W/m² for the SW fluxes.

How to cite: Velazquez Blazquez, A., Domenech, C., Baudrez, E., Clerbaux, N., and Salas Molar, C.: Radiative fluxes estimation for the Broadband Radiometer (BBR) on EarthCARE: The BMA-FLX product, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20094,, 2024.

Robin Hogan, Shannon Mason, Fabian Jakub, and Mark Fielding

Variational retrievals, data assimilation, and model evaluation in observation space, all rely on accurate instrument simulators, or forward models. The scientific challenge is to find innovative approximations to the radiative transfer that make them fast enough to use iteratively, while retaining accuracy. In this presentation I will summarize how the development of various forward models, particularly in the context of synergistic retrievals from EarthCARE and the A-Train, has the capability to reveal important cloud and precipitation properties that would otherwise remain hidden, and potentially even to develop new satellite concepts. For example, our radar and lidar “Multiscatter” model enables the extinction profile to be retrieved in ice and liquid clouds even in the presence of lidar multiple scattering.  Our “FLOTSAM” solar radiance model can work with profiles containing arbitrary combinations of particles, and surprisingly can help improve rain-rate retrievals by better providing the additional information needed to partition the radar path-integrated attenuation into the contributions from liquid clouds and rain. The Two-Stream Source Function (TSSF) infrared and microwave radiance model enables us to interpret 94-GHz brightness temperature, which provides important additional information on precipitating ice and liquid clouds.  I will end by presenting a new radiance model for cloud/storm-resolving models that can efficiently represent horizontal radiation transport between columns; this could enable future retrievals and assimilation to take full account of 3D radiative effects.

How to cite: Hogan, R., Mason, S., Jakub, F., and Fielding, M.: Harnessing the power of forward models: past, present and future, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8361,, 2024.

Jonas von Bismarck, Robert Koopman, Stephanie Rusli, Malcolm Davidson, Dirk Bernaerts, Kotska Wallace, Thorsten Fehr, Timon Hummel, Vasileios Tzallas, Bjoern Frommknecht, and Michael Eisinger


The Earth Cloud Aerosol and Radiation Explorer (EarthCARE) is a satellite mission developed by the European Space Agency (ESA) in collaboration with the Japan Aerospace Exploration Agency (JAXA) to measure global profiles of aerosol, cloud and precipitation properties along with radiative fluxes and derived warming rates, with the goal of advancing our understanding of cloud-aerosol and radiation interactions and the Earth's radiative budget.  

Assuring the data quality of EarthCARE science products early after launch is an essential effort. This will be realised based on contributions from the independent EarthCARE validation team (ECVT) under coordination by ESA as well as monitoring-, calibration- and campaign activities performed under ESA (co-)management.  


An early focus to stabilize the data quality will be on airborne activities underflying the satellite with remote sensing and in-situ payloads. This will be done either in the context of larger science field campaigns or in individual activities, flanked by ground based measurement activities. 


The presentation will give an overview of ESA’s planned EarthCARE campaign activities, both directly implemented by ESA and in collaboration with science teams, and selected airborne and ground based instrument developments critical for the EarthCARE validation. 

How to cite: von Bismarck, J., Koopman, R., Rusli, S., Davidson, M., Bernaerts, D., Wallace, K., Fehr, T., Hummel, T., Tzallas, V., Frommknecht, B., and Eisinger, M.: EarthCARE Cal/Val Campaigns - Overview, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17361,, 2024.

Peristera Paschou, Eleni Marinou, Jos de Kloe, Dave Donovan, Gerd-Jan van Zadelhoff, Kalliopi-Artemis Voudouri, and Vassilis Amiridis

The Earth Clouds, Aerosol and Radiation Explorer (EarthCARE) is a joint mission of the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) for monitoring the aerosols, clouds, and precipitation, and for radiation closure studies. The Atmospheric Lidar (ATLID) is a High Spectral Resolution Lidar system and one of the four instruments that will be deployed onboard the platform. ATLID will use linearly polarized emission at 355 nm while pointing at 3o off-nadir and will detect the molecular (Rayleigh) and particulate (Mie) backscattered signals as well as the cross-polar component of the backscatter signals, aiming to provide profiles of the optical properties of aerosols and optically thin clouds such as the particle backscatter and extinction coefficients, and the depolarization ratio. In preparation for the calibration and validation (cal/val) activities that will be performed for ATLID upon the EarthCARE launch in May 2024, a lidar simulator tool (CARDINAL Campaign Tool; CCT) has been developed for providing realistic simulations of the ATLID lidar signals and the Level 1 (L1) products of the attenuated particulate (Mie) backscatter, the attenuated molecular (Rayleigh) backscatter, and the attenuated cross-polar backscatter. In brief, the CCT workflow includes the parametrization of an atmospheric scene with the use of model fields and/or measurements from airborne or ground-based lidars, a lidar radiative transfer model, and an instrument model based on the ATLID design. The CCT simulates the lidar signals that would be recorded from ATLID for the provided atmospheric scene and obtains the corresponding ATLID L1 products.

In this study, measurements of eVe lidar from the ASKOS campaign (Cabo Verde, 2021/2022), are used as an input in the simulator for obtaining realistic ATLID L1 profiles. eVe lidar is a combined linear/circular polarization Raman lidar operating at 355 nm for aerosol profiling and consists ESA’s ground reference system for the cal/val of the ESA Aeolus and EarthCARE missions. Several cases of different aerosol layers and cirrus clouds are investigated.

Furthermore, the simulated ATLID L1 profiles will be used in the Level 2A processing chain (A-PRO) to derive realistic profiles of the particle backscatter and extinction coefficients, and the linear depolarization ratio. The realistic ATLID L2A profiles will be compared with the corresponding L2 profiles from eVe lidar, aiming to investigate the detection sensitivity of ATLID products on real aerosol layers.

Upcoming plans for the validation of EarthCARE mission include the exploitation of eVe lidar in an overpass cross point. The key aspects of this validation will be presented. In brief, the system will undergo an upgrade to enhance its capabilities for the cal/val activities of EarthCARE mission, retaining its combined linear/circular configuration while incorporating state-of-the-art equipment tailored for measurements on multiple scattering effects and automations to enhance the measurement procedures.

How to cite: Paschou, P., Marinou, E., de Kloe, J., Donovan, D., van Zadelhoff, G.-J., Voudouri, K.-A., and Amiridis, V.: A sensitivity study using the ATLID lidar simulator and upcoming plans for the validation of EarthCARE mission, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18670,, 2024.

Jürgen Fuchsberger, Andreas Kvas, Gottfried Kirchengast, Ulrich Foelsche, Esmail Ghaemi, Robert Galovic, Daniel Scheidl, and Christoph Bichler

The WegenerNet 3D Open-Air Laboratory for Climate Change Research, located in southeastern Austria in an area of about 22 km x 16 km around the city of Feldbach (46.93°N, 15.90°E), provides a unique setup for atmospheric monitoring and validation of satellite data products. Its 3D instrumentation consists of a polarimetric X-band Doppler weather radar, a microwave radiometer for vertical profiling of temperature, humidity, and cloud liquid water, an infrared cloud structure radiometer, and a water-vapor-mapping GNSS station network. These 3D sensors complement the high-density WegenerNet hydrometeorological ground station network, which is comprised of 156 stations measuring precipitation, temperature, humidity, and (at selected locations) wind as well as soil parameters.

This highly synergistic measurement setup enables robust internal cross-evaluation, calibration and quality control for obtaining reliable observations and derived WegenerNet data products. The 3D instrumentation is operational since mid-2021 and will provide a consistent validation reference data record throughout the EarthCARE mission lifetime. With its ground-based observations of cloud base height, melting layer base and top heights, liquid water content, precipitation rates, and hydrometeor classification, the WegenerNet contributes specifically to the validation of EarthCARE L2a and L2b cloud and precipitation data products. This presentation summarizes the validation preparation activities carried out so far, with focus on the EarthCARE validation rehearsal, and gives an outlook on the planned post-launch validation work during the actual cal/val phase.

How to cite: Fuchsberger, J., Kvas, A., Kirchengast, G., Foelsche, U., Ghaemi, E., Galovic, R., Scheidl, D., and Bichler, C.: Validation of EarthCARE Cloud and Precipitation Products through the WegenerNet 3D Open-Air Laboratory facilities, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8203,, 2024.

Sabrina Zechlau, Silke Groß, Ulla Wandinger, and Holger Baars

The joint ESA and JAXA Earth Explorer mission EarthCARE is designed to close gabs in the knowledge of aerosol, clouds and their interactions, and effects on radiation. For this the platform comprises four remote sensing instruments observing the vertical structure of the atmosphere with a highly spectral resolving lidar and a doppler cloud radar. Together with a hyperspectral imager radiation fluxes can be inferred and compared to the measurements of the on-board broad band radiometer. Based on these four instruments EarthCARE will provide over 40 data products, which are partly synergistic products of observations of all instruments. For the success of the mission it is therefore crucial to exactly validate the individual data products and to quantify their errors. A variety of observational sources are used, reaching from ground-based stations and networks to airborne measurements, and from satellite observations to modelled data. Already in the past a number of dedicated validation campaigns to prepare for validation from German research institutes were carried out with eg. the ground-based cloud observation system LACROS or with an EarthCARE-like payload on board the German research aircraft HALO. After launch a continuous validation of EarthCARE products will be necessary. For this the German Initiative for the Validation of EarthCARE (GIVE) bundles the expertise of the German atmospheric research community and aims at the validation of the entire chain of EarthCARE Level 1 and 2 products and the evaluation of related algorithms and instrument calibrations. The GIVE project will include dedicated campaigns as well as long‐term support over the lifetime of the mission. Here we want to introduce in general the German project EC-KLIM (former project office) to prepare for the use of EarthCARE, and especially of the GIVE project. We will present an overview of past preparation campaigns and of planned German validation activities.

How to cite: Zechlau, S., Groß, S., Wandinger, U., and Baars, H.: EC-KLIM – Coordination of German EarthCARE Validation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14900,, 2024.

Alessandro Bracci, Kaori Sato, Luca Baldini, Federico Porcú, Roberta Paranunzio, and Hajime Okamoto

Validating satellite measurements and geophysical retrievals is crucial for Earth observation missions, particularly in remote regions like Antarctica. This task faces challenges due to the harsh environment, logistical complexities, equipment maintenance, and operational costs. In Antarctica, where satellite observations play a pivotal role in estimating precipitation, validating satellite products through ground-based measurements is imperative but limited.

Cloud Profiling Radar (CPR) on NASA's CloudSat satellite provides reflectivity profiles at W-band (94 GHz), while the upcoming ESA/JAXA EarthCARE satellite will offer Doppler profiles in addition to reflectivity profiles. Despite efforts to enhance instrumentation for ice particle profiling at some Antarctic research stations, widely-used instruments include the Micro Rain Radar (MRR) and laser disdrometers.

This work introduces a novel validation methodology, K2W, which combines ground-based reflectivity profiles at K-band (24 GHz) from MRR and laser disdrometer observations. K2W enables the simulation of reflectivity and Doppler profiles at W-band, facilitating the validation of satellite-borne radar measurements at 94 GHz.

A comparison between CloudSat reflectivity profiles and K2W profiles during a satellite overpass at the Italian Antarctic station “Mario Zucchelli” revealed a mean difference of 0.2 dB at the lowest satellite radar range bin, with a time lag within ±12.5 min and distance within 25 km around the CloudSat overpass. Additionally, K2W simulated the 94 GHz Doppler velocity below 1 km altitude expected by EarthCARE, yielding a standard deviation of the simulated Doppler velocity less than 0.2 m s-1.

The use of simulated K2W profiles significantly enhances precipitation quantification over Antarctica and validates satellite measurements with reduced attenuation compared to ground-based W-band radar. K2W, utilizing MRR and disdrometer available at most Antarctic stations, broadens the scope for validation sites. The proposed methodology extends its applicability to assessing EarthCARE CPR Doppler velocity products and Level 2 standard precipitation products at various ground observation sites.

How to cite: Bracci, A., Sato, K., Baldini, L., Porcú, F., Paranunzio, R., and Okamoto, H.: Enhancing Satellite Validation in Antarctica: A Novel K2W Methodology for Comparing Ground-Based Measurements at K-band with Spaceborne Radar Observations Collected at W band, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22426,, 2024.

Loredana Spezzi, Alessio Bozzo, Phil Watts, John Jackson, and Andre Belo do Couto

The EUMETSAT central facility generates and disseminates several cloud products from both geostationary and low-Earth orbit passive sensors, which serve a variety of applications, spanning from nowcasting, to numerical weather prediction to climate monitoring. The retrieved cloud parameters include cloud/dust/ash detection, cloud top height and microphysics (particle effective radius and optical thickness). All EUMETSAT products are validated and continuously quality monitored against independent reference data to ensure state-of-the-art algorithm performance, product quality/accuracy compliant with user and operational service requirements, and stability and continuity/consistency over time (i.e., coping with instrument degradation, algorithm evolutions, updated calibration, etc.).

This contribution provides an overview of the tools developed at EUMETSAT to perform the monitoring and validation of cloud products against lidar/radar measurements, which have established themselves as a trustworthy source for the detection of cloud layers and superior to any other validation data source when it comes to estimate the cloud height, particle microphysical and optical properties. We focus on the status of these tools and the plans for their further development and release to users. The tools are fully automated and handle the validation of products from both geostationary and polar-orbiting satellites, including data download and organisation, instrument co-location and the development of comparison metrics. The toolkit includes:

  • A tool performing the validation of EUMETSAT against space-based radar and lidar measurements. For almost two decades (since 2006), the CloudSat and CALIPSO observations have been the prime reference source for this validation. EarthCARE will provide the natural continuation to the observations provided by these two instruments, which reached their end of life in autumn 2023. We discuss the use of EarthCARE products as envisaged in the validation activities with a particular focus on the retrieval of cloud properties based on the synergistic use of lidar, radar and multi-spectral imager data. Furthermore, the higher sensitivity measurements expected from HSRL and CPR on board EarthCARE with respect to CALIPSO and CloudSat will require careful investigations in order to transfer the current experience in the use of A-Train products as a validation reference to the new EarthCARE products.
  • A tool performing the validation of EUMETSAT cloud products against ground-based radar and lidar measurements from ACTRIS (the European Research Infrastructure for the observation of Aerosol, Cloud and Trace Gases), specifically using the cloud products generated by the ACTRIS-Cloudnet processing facility maintained by the Finnish Meteorological Institute (FMI). This validation activity fills in the gap between CloudSat/CALIPSO end of life and EarthCARE launch.
  • METIS-Clouds (Monitoring and Evaluation of Thematic Information from Space), a web application tool providing access to the collection of monitoring and validation results of EUMETSAT cloud products, on a global and regional level. This collection is exploited by both the in-house algorithm developers (to identify and fix issues, bugs, etc.) and the users (to assess the product accuracy).

How to cite: Spezzi, L., Bozzo, A., Watts, P., Jackson, J., and Belo do Couto, A.: Use of EarthCARE products within the EUMETSAT validation facility for Level 2 Cloud products  , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18904,, 2024.

Jesús Yus-Díez, Luka Drinovec, Marija Bervida, Uroš Jagodič, Blaž Žibert, Matevž Lenarčič, Eleni Marinou, Peristera Paschou, Nikolaos Siomos, Holger Baars, Ronny Engelmann, Arnett Skupin, Cordula Zenk, Thorsten Fehr, Andres Alastuey, Adolfo Gonzalez-Romero, Marco Pandolfi, Carlos Perez García-Pando, and Griša Močnik

Aerosol absorption coefficient measurements classically feature a very large uncertainty, especially given the absence of a reference method. The most used approach using filter-photometers is by measuring the attenuation of light through a filter where aerosols are being deposited. This presents several artifacts, with cross-sensitivity to scattering being most important at high single scattering albedo with the error exceeding 100%. 

We present lab campaign results where we have resuspended dust samples from different mid-latitude desert regions and measured the dust absorption and scattering coefficients, their mass concentration and the particle size distribution. The absorption coefficients were measured with two types of filter photometers: a Continuous Light Absorption Photometers (CLAP) and a multi-wavelength Aethalometer (AE33). The  dual-wavelength photo-thermal interferometer (PTAAM-2λ) was employed as the reference. Scattering coefficients were measured with an Ecotech Aurora 4000 nephelometer. The mass concentration was obtained after the weighting of filters before and after the sampling, and the particle size distribution (PSD) was measured by means of optical particle counters (Grimm 11-D).

Measurements of the scattering with the nephelometer and absorption with the PTAAM-2λ we obtained the filter photometer multiple scattering parameter and cross-sensitivity to scattering as a function of the different sample properties. Moreover, by determining the mass concentration and the absorption coefficients of the samples, we derived the mass absorption cross-sections of the different dust samples, which can be linked to their size distribution as well as to their mineralogical composition.

The focus of the JATAC campaign in September 2021 and September 2022 on and above Cape Verde Islands was on the calibration/validation of the ESA Aeolus satellite ALADIN lidar, however, the campaign also featured secondary scientific climate-change objectives. As part of this campaign, a light aircraft was set-up for in-situ aerosol measurements. Several flights were conducted over the Atlantic Ocean up to and above 3000 m above sea level during intense dust transport events. The aircraft was instrumented to determine the absorption coefficients using a pair of Continuous Light Absorption Photometers (CLAPs) measuring in the fine and coarse fractions separately, with parallel measurements of size distributions in these size fractions using two Grimm 11-D Optical Particle Size Spectrometers (OPSS). In addition, we performed measurements of the total and diffuse solar irradiance with a DeltaT SPN1 pyranometer.

The combination of the absorption and PSD with source identification techniques enabled the separation of the contributions to  absorption by dust and black carbon. The atmospheric heating rate of these two contributions was determined by adding the irradiance measurements. Therefore, the integration of the results from the Using laboratory resuspension experiments  to interpret the airborne measurements is of great relevance for the determination  of the radiative effect of the Saharan Aerosol Layer as measured over the tropical Atlantic ocean.

How to cite: Yus-Díez, J., Drinovec, L., Bervida, M., Jagodič, U., Žibert, B., Lenarčič, M., Marinou, E., Paschou, P., Siomos, N., Baars, H., Engelmann, R., Skupin, A., Zenk, C., Fehr, T., Alastuey, A., Gonzalez-Romero, A., Pandolfi, M., Perez García-Pando, C., and Močnik, G.: Aerosol dust absorption - measurements with a reference instrument (PTAAM-2λ) and impact on the climate as measured in airborne  JATAC/CAVA-AW 2021/2022 campaigns, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17933,, 2024.

Marija Bervida Mačak, Jesús Yus-Díez, Luka Drinovec, Uroš Jagodič, Blaž Žibert, Matevž Lenarčič, Eleni Marinou, Peristera Paschou, Nikolaos Siomos, Holger Baars, Ronny Engelmann, Annett Skupin, Athina Augusta Floutsi, Cordula Zenk, Thorsten Fehr, and Griša Močnik

The JATAC campaign in September 2021 and September 2022 on and above Cape Verde Islands resulted in a large in-situ and remote measurement dataset. Its main objective was the calibration and validation of the ESA satellite Aeolus ALADIN Lidar. The campaign also featured secondary scientific objectives related to climate change. Constraining remote sensing measurements with those provided by in-situ instrumentation is crucial for proper characterization and accurate description of the 3-D structure of the atmosphere.

We present the results performed with an instrumented light aircraft (Advantic WT-10) set-up for in-situ aerosol measurements. Twenty-seven flights were conducted over the Atlantic Ocean at altitudes around and above 3000 m above sea level during intense dust transport events. Simultaneous measurements with PollyXT, and eVe ground-based lidars took place, determining the vertical profiles of aerosol optical properties, which were also used to plan the flights.

The aerosol light extinction coefficient was obtained at three different wavelengths as a combination of the absorption coefficients determined using Continuous Light Absorption Photometers (CLAP) and the scattering coefficients measured with an Ecotech Aurora 4000 nephelometer, which also measured the backscatter fraction. The particle size distributions above 0.3 µm diameter were measured with two Grimm 11-D Optical Particle Size Spectrometers (OPSS). Moreover, CO2 concentration, temperature, aircraft GPS position and altitude, air and ground speed were also measured.

We compare the in-situ aircraft measurements of the aerosol extinction coefficients with the AEOLUS lidar derived extinction coefficients, as well as with the ground-based eVe and PollyXT lidar extinction coefficients when measurements overlapped in space and time. The comparison was performed at the closest available wavelengths, with in-situ measurements inter/extrapolated to those of the lidar systems.

In general we find an underestimation of the extinction coefficient obtained by lidars compared to the in-situ extinction coefficient. The slopes of regression lines of ground-based lidars, PollyXT and eVe, against the in-situ measurements are characterised by values ranging from 0.61 to 0.7 and R2 between 0.71 and 0.89. Comparison further suggests better agreement between Aeolus ALADIN lidar and the in-situ measurements. Relationship described by fitting the Aeolus to in-situ data is characterised by the slope value 0.76 and R2 of 0.8.

The causes of better agreement of the in-situ measurements with the ALADIN lidar than with the surface based ones are being studied, with several reasons being considered: a) lower spatial and temporal resolution which homogenize the area of study in comparison with the very fine vertical variations of the aerosols, which can be detected with the surface-based measurements, impairing the comparison with highly vertically resolved ground-lidar measurements while not affecting averaged space-borne lidar; b) the effect of lower clouds/ Saharan air layers on the attenuation of the lidar signal.

The presented results show the importance of the comparison of the remote with in-situ measurements for the support of the research on evolution, dynamics, and predictability of tropical weather systems and provide input into and verification of the climate models.

How to cite: Bervida Mačak, M., Yus-Díez, J., Drinovec, L., Jagodič, U., Žibert, B., Lenarčič, M., Marinou, E., Paschou, P., Siomos, N., Baars, H., Engelmann, R., Skupin, A., Floutsi, A. A., Zenk, C., Fehr, T., and Močnik, G.: Aerosol Light Extinction Coefficient Closure - Comparison of Airborne In-situ Measurements with LIDAR measurements during JATAC/CAVA-AW 2021/2022 campaigns, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18425,, 2024.

Artem Feofilov, Hélène Chepfer, and Vincent Noël

Recognizing the need for a comprehensive lidar system performance analysis, we present a method for day-to-day assessment of the ATLID/EarthCARE lidar system. Unlike traditional calibration/validation methods involving in situ measurements or comparisons with ground-based, air- and space-borne instruments, our approach dispenses with the need for a second instrument. Instead, we focus on stability control checks using the atmosphere and surface as a 'reference,' assuming their properties remain constant during the lidar mission's lifetime.

Leveraging L1 data flow, our method evaluates critical performance aspects, including the stability of ATLID channels, accuracy of cross-talk coefficients, and the consistency of day- and nighttime noise. Employing a clustering algorithm on scattering ratio histograms, we monitor radiation detection stability globally across diverse atmospheric scenarios.

Defining 11 parameters related to surface reflection, stratospheric noise, and scattering ratio histograms, we showcase the feasibility of our approach using CALIOP L1 data. We also present results from our analysis of simulated ATLID data, demonstrating the sensitivity of the proposed quality control indicators to various experimental issues.

How to cite: Feofilov, A., Chepfer, H., and Noël, V.: Performance Analysis of the ATLID Lidar: A Multi-Parameter Statistical Approach Using L1 Data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11671,, 2024.

Lev D. Labzovskii, Gerd-Jan van Zadelhoff, David P. Donovan, Jos de Kloe, L. Gijsbert Tilstra, Ad Stoffelen, Piet Stammes, and Damien Josset

We previously discovered the sensitivity of Aeolus lidar surface returns (LSR) to surface characteristics and reported very good agreement of LSR with Lambertian Equivalent Reflectances from passive remote sensing instruments for the first year of Aeolus on orbit. In this way, we provided the first evidence that active remote sensing can be used for retrieving unidirectional UV surface reflectivity. Here, as a continuation of this effort, we report the detailed methodological solutions for retrieving and evaluating LSR to be implemented as official L2A product during Phase-F of Aeolus project for its entire lifetime. Unlike our previous report that relied on detecting surface bin using our own methodology and assumptions, we now align the approach of detecting surface bins with the official Aeolus processing methodology for retrieving LSR and elaborate on the resultant differences. Besides that, we report how this successful application of atmospheric spaceborne lidar data for inferring land surface reflectivity properties can be translated for future lidar missions such as EarthCARE and Aeolus-2. On one hand, our results will briefly introduce all the details of the LSR retrieval for Aeolus with its unique and complex optical setup (highly-non nadir incidence and UV wavelength) for broad audience for the first time. On the other hand, we will shed light on the opportunities and challenges of LSR-alike retrievals for future lidar spaceborne missions, thereby trying to minimize the key methodological uncertainties associated with implementation of LSR algorithms.

How to cite: Labzovskii, L. D., van Zadelhoff, G.-J., Donovan, D. P., de Kloe, J., Tilstra, L. G., Stoffelen, A., Stammes, P., and Josset, D.: Presenting lidar surface returns as Aeolus product with the outlook on future spaceborne lidar missions including EarthCARE and Aeolus-2 , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12553,, 2024.

Thanasis Georgiou, Athanasios Tsikerdekis, Konstantinos Rizos, Emmanouil Proestakis, Antonis Gkikas, Eleni Drakaki, Anna Kampouri, Holger Baars, Athena Augousta Floutsi, Eleni Marinou, Angela Benedetti, Will McLean, Christian Retscher, Dimitris Melas, and Vassilis Amiridis

EarthCARE, ESA’s and JAXA’s joint mission, is expected to launch in 2024 carrying ATLID, a high-spectral resolution lidar with depolarization capability. The instrument will provide valuable data for characterizing atmospheric aerosols and for improving atmospheric composition modelling. The aim of this study is to show how working with ESA’s Aeolus wind mission prepares us for taking advantage of ATLID.

Aeolus, which launched in 2018 and deorbited in 2023, was not specifically designed to observe aerosols but still provided aerosol products. Due to the lack of a cross-polar channel, it underestimated the aerosol-related backscatter by as much as 50% in scenes with non-spherical particles. During the ESA L2A+ project, an enhanced aerosol product was developed through data fusion with other data sources (such as NASA’s CALIPSO mission) to account for Aeolus deficiencies. The impact of this new product was assessed through assimilation experiments in regional NWP models, showing both the direct improvements of the new product, as well as the betterment of aerosol fields in regional models through assimilation of a profiling instrument. Our results were validated using data from the ESA-ASKOS tropical campaign, which took place in Cabo Verde during Summer and Autumn of 2021 and 2022.

The open-source tools created for Aeolus are further developed to support EarthCARE. Working with simulated data, we show the impact of ATLID profile assimilation on both the representation of aerosols in the model, as well as the impact on numerical weather prediction through radiative feedback. The experiments are done using the Weather Research and Forecasting (WRF) model, alongside the Data Assimilation Research Testbed (DART), with AEOLUS and EarthCARE support added.

The L2A+ team acknowledges support by ESA in the framework of the "Enhancing Aeolus L2A for depolarizing targets and impact on aerosol research and NWP project (4000139424/22/I-NS). This work was supported by computational time granted from the National Infrastructures for Research and Technology S.A. (GRNET S.A.) in the National HPC facility - ARIS - under project ID pr014048_thin.

How to cite: Georgiou, T., Tsikerdekis, A., Rizos, K., Proestakis, E., Gkikas, A., Drakaki, E., Kampouri, A., Baars, H., Floutsi, A. A., Marinou, E., Benedetti, A., McLean, W., Retscher, C., Melas, D., and Amiridis, V.: Using AEOLUS Aerosol Assimilation to pave the way for EarthCARE, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10363,, 2024.

Posters virtual: Thu, 18 Apr, 14:00–15:45 | vHall X5

Display time: Thu, 18 Apr 08:30–Thu, 18 Apr 18:00
Tadayasu Ohigashi and Ryohei Misumi

The National Research Institute for Earth Science and Disaster Resilience owns five scanning Ka-band cloud radars. Using these radars, we are planning to validate the cloud profiling radar (CPR) of the EarthCARE satellite. The EarthCARE CPR only observes along the line directly under the satellite path and has a return period of about 25 days. Therefore, we will facilitate the comparison by collecting data from what we can consider to be the similar region as the EarthCARE path. Statistical validation will be performed by creating a Contoured Frequency by Altitude/Temperature Diagram (CFAD/CFTD) and comparing the distributions. Both case and relatively long-term comparisons are possible. On the other hand, although the opportunity is rare, it is possible to compare the vertical profiles at the intersection with the vertical (RHI) observations of the ground-based radar if the EarthCARE path comes within the range of the ground-based cloud radar with the observation range of 30 km. Three-dimensional observations using Plan Position Indicator (PPI) scans can be used to generate data on the Cartesian grid (CAPPI data). From this CAPPI data, it is possible to create a vertical cross section along the path of the EarthCARE satellite. Because of the limited number of elevation angles, the comparison is relatively coarse in the vertical direction. Since this observation is not done in the vertical direction, only radar reflectivity is used for comparison, not Doppler velocity. Other methods of verifying liquid water contents using cloud radar and microwave radiometer are also under consideration.

How to cite: Ohigashi, T. and Misumi, R.: Ground-based scanning Ka-band cloud radar observations for validation of EarthCARE Cloud Profiling Radar (CPR), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18461,, 2024.