GI4.1

EDI
Lidar remote sensing of the atmosphere

This session invites contributions on the latest developments and results in lidar remote sensing of the atmosphere, covering • new lidar techniques as well as applications of lidar data for model verification and assimilation, • ground-based, airborne, and space-borne lidar systems, • unique research systems as well as networks of instruments, • lidar observations of aerosols and clouds, thermodynamic parameters and wind, and trace-gases. Atmospheric lidar technologies have shown significant progress in recent years. While, some years ago, there were only a few research systems, mostly quite complex and difficult to operate on a longer-term basis because a team of experts was continuously required for their operation, advancements in laser transmitter and receiver technologies have resulted in much more rugged systems nowadays, many of which are already operated routinely in networks and some even being automated and commercially available. Consequently, also more and more data sets with very high resolution in range and time are becoming available for atmospheric science, which makes it attractive to consider lidar data not only for case studies but also for extended model comparison statistics and data assimilation. Here, ceilometers provide not only information on the cloud bottom height but also profiles of aerosol and cloud backscatter signals. Scanning Doppler lidars extend the data to horizontal and vertical wind profiles. Raman lidars and high-spectral resolution lidars provide more details than ceilometers and measure particle extinction and backscatter coefficients at multiple wavelengths. Other Raman lidars measure water vapor mixing ratio and temperature profiles. Differential absorption lidars give profiles of absolute humidity or other trace gases (like ozone, NOx, SO2, CO2, methane etc.). Depolarization lidars provide information on the shapes of aerosol and cloud particles. In addition to instruments on the ground, lidars are operated from airborne platforms in different altitudes. Even the first space-borne missions are now in orbit while more are currently in preparation. All these aspects of lidar remote sensing in the atmosphere will be part of this session.

Co-organized by AS3/CL5.1
Convener: Andreas Behrendt | Co-conveners: Diego Lange Vega, Joelle BuxmannECSECS, Paolo Di Girolamo, Silke GrossECSECS
Presentations
| Fri, 27 May, 08:30–09:54 (CEST)
 
Room 0.51

Presentations: Fri, 27 May | Room 0.51

Chairpersons: Paolo Di Girolamo, Joelle Buxmann, Diego Lange Vega
08:30–08:36
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EGU22-3275
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Presentation form not yet defined
Diego Lange Vega, Andreas Behrendt, Christoph J Senff, Florian Späth, and Volker Wulfmeyer

Since there are only a very few suitable measurements, the thermodynamic field of the lower troposphere is mostly still Terra Incognita. To close this gap, we developed a thermodynamic profiler based on the Raman lidar technique. We call this instrument Atmospheric Raman Temperature and Humidity Sounder (ARTHUS) (Lange et al. 2019). ARTHUS can be operated on ground-based, ship-borne and airborne platforms.

Due to an advanced design of the transmitter and the receiver, simultaneous profiling of temperature (T) and water-vapor mixing ratio (WVMR) is possible with unprecedented accuracies and resolutions. Typical resolutions are a few seconds and meters in the lower troposphere. With the measurements themselves, also the statistical uncertainties are derived. The design of the system permits measurements in all weather conditions and even in clouds and rain up to an optical thickness of approx. 2.

Stable 24/7 operations over long periods were achieved during several field campaigns and at the Land Atmosphere Feedback Observatory (LAFO) accumulating almost a year of data until now and covering a huge variety of weather conditions.

During the EUREC4A field campaign (Stevens et al, 2020), for example, ARTHUS was deployed on board RV Maria S Merian, to study ocean-atmosphere interaction, (18 January to 18 February 2020). ARTHUS was combined with one Doppler lidar in vertically staring mode and a second one in a 6-beam scanning mode.

Between 15 July and 20 September 2021, ARTHUS was deployed at Lindenberg Observatory from the German Weather Service (DWD). The objective of the campaign was to demonstrate the potential of ARTHUS in the framework of a ground-based measurement campaign and the evaluation of the data obtained. The long-term stability, accuracy and high resolution of ARTHUS during the day and at night were demonstrated.

We also demonstrate that ARTHUS is capable of resolving (1) the strength of the inversion layer at the atmospheric boundary layer (ABL) top and thus the ABL depth zi, (2) elevated lids in the free troposphere, and (3) turbulent fluctuations in WVMR and T. In combination with Doppler lidar, the latter permits measurements of sensible and latent heat flux profiles in the convective ABL and thus flux-gradient relationships (Behrendt et al. 2020). Consequently, ARTHUS can be applied for process studies such as land-atmosphere feedback, weather and climate monitoring, model verification, and data assimilation in weather forecast models.

At the conference, highlights of the measurements during the last three years will be shown.

Stevens et. al. 2021, https://doi.org/10.5194/essd-2021-18

Lange et al. 2019, https://doi.org/10.1029/2019GL085774

Behrendt et al. 2020, https://doi.org/10.5194/amt-13-3221-2020

How to cite: Lange Vega, D., Behrendt, A., Senff, C. J., Späth, F., and Wulfmeyer, V.: The Atmospheric Raman Temperature and Humidity Sounder: Highlights of Three Years of Ground-based and Ship-borne Boundary Layer Measurements with Turbulence Resolution, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3275, https://doi.org/10.5194/egusphere-egu22-3275, 2022.

08:36–08:42
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EGU22-4735
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ECS
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On-site presentation
Andrea Burgos Cuevas, Adolfo Magaldi Hermosillo, David Adams, Michel Grutter de la Mora, Jorge L. Garcia Franco, and Angel Ruiz Angulo

The Atmospheric Boundary Layer (ABL) height is a key parameter in air quality research as well as in order to parametrize numerical simulations and forecasts. The identification of thermally stable layers has been one of the most common approaches in order to estimate this height. However, radiosonde's coarse temporal resolution is not enough to investigate the diurnal cycle of the ABL. Remote sensing has overcome this problem with a high temporal resolution. The backscatter retrieved by ceilometers elucidates the height that aerosols are able to reach and therefore has been used to estimate ABL height. Additionally, the implementation of Doppler lidars, and the velocity profiling provided by them, makes possible to investigate ABL via turbulence variables. However, different retrievals of ABL height are not usually coincident with each other and this issue becomes more evident over topographically complex terrain, such as Mexico City. It has been previously shown that the aerosol layer and the convective boundary layer height are generally not coincident over mountainous terrains. In this presentation we show that, at daytime hours, the convective boundary layer height (retrieved with Doppler lidar data) is lower than the aerosol layer height (retrieved with ceilometer data) during one year over Mexico City. Diurnal and monthly variabilities are discussed and the remote sensing-retrieved heights are compared with thermally stable layers estimated from radiosonde data. We show that multiple thermally stable layers develop, the upper ones are similar to the ceilometer retrieved heights and the lower ones are approximately as high as the Doppler lidar ones. Finally, the influence of radiation and precipitation over the retrieved heights is discussed over the year. The present research illustrates how the comparison between ceilometer backscatter and Doppler lidar ABL height retrievals can contribute to investigate the complexity of the ABL height over the mountainous terrain of Mexico City.

 

How to cite: Burgos Cuevas, A., Magaldi Hermosillo, A., Adams, D., Grutter de la Mora, M., Garcia Franco, J. L., and Ruiz Angulo, A.: Comparison between Atmospheric Boundary Layer Height remote sensing-retrievals over a complex topography, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4735, https://doi.org/10.5194/egusphere-egu22-4735, 2022.

08:42–08:48
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EGU22-5644
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Presentation form not yet defined
Paolo Di Girolamo, Alberto Cosentino, Francesco Longo, Noemi Franco, Davide Dionisi, Donato Summa, Simone Lolli, Enrico Suetta, Alessandro Perna, and Simona Zoffoli

The Italian space industry, and specifically Leonardo S.p.A., has gained unique skills at an international level in the development of space-qualified power laser sources with for lidar Earth observation applications (Aeolus, EarthCARE). Moreover, Leonardo S.p.A. and the Italian optical industry, has a consolidated technical-scientific knowledge and consolidated experience in the design and development of lidar receiver sub-systems (telescopes, optical devices and sensors) with  space applications. The Italian Space Agency (ASI) intends to benefit from long-term expertise to design and develop a lidar system for Earth observation applications. Two separate feasibility studies, one focusing of technical aspects and one focusing on scientific aspects, are presently underway to define mission goals and a possible instrument layout.
CALIGOLA has a primary focus on the atmosphere, but also a strong focus on the study of the Ocean-Earth-Atmosphere system and the mutual interactions within it. Exploiting the three Nd: YAG laser emissions at 354.7, 532 and 1064 nm and the elastic (Rayleigh-Mie) and Raman lidar echoes from atmospheric constituents, CALIGOLA is conceived to carry out three-wavelength particle backscatter and depolarization ratio and two-wavelength particle extinction profile measurements from aerosols and clouds to be used to retrieve their microphysical and dimensional properties. Furthermore, measurement of the elastic backscattered echoes from the sea surface and the underlying layers, and their degree of depolarization, CALIGOLA will be exploited to characterize sea optical properties (ocean color) and the suspended particulate matter, which are needed to study the seasonal and inter-annual phytoplankton dynamics and to improve the understanding of the role of phytoplankton in marine biogeochemistry, in the global carbon cycle and in the response of marine ecosystems to climate variability. A specific measurement channel will be dedicated to fluorescence measurements from atmospheric aerosols and marine chlorophyll, for the purpose of aerosol typing and for characterizing ocean primary production. Aerosol fluorescence measurements at 680 nm/460 nm are also planned for the purpose of aerosol typing. CALIGULA will also allow accurate measurements of the small-scale variability of the earth's surface elevation primarily associated with variations in the terrain, vegetation and forest canopy height.
The CALIGOLA project is explicitly included the on-going Three-Year Activity Plan (2021-2023) of the Italian Space Agency, with a scheduled tentative launch window of 2026-2028. The considered strategy to develop the above described space lidar mission in such a short time relies on the maximum exploitation of subsystems already developed at national level for space applications, with a high TRL (TRL>7), ultimately leading to a space mission with high impact and scientific timeliness. The Phase A study of the technological feasibility of the laser source is on-going, commissioned by ASI to Leonardo S.p.A., and scientific studies in support of the mission also on-going, with the University of Basilicata being the leading scientific institution. The Italian Space Agency is willing to pursue this mission in a coordinated way with one or more other European or extra-European Space Agencies, with a bilateral or multi-lateral contributed mission approach, and, in this regard, any interest from other Agencies is welcome and desired.

How to cite: Di Girolamo, P., Cosentino, A., Longo, F., Franco, N., Dionisi, D., Summa, D., Lolli, S., Suetta, E., Perna, A., and Zoffoli, S.: Cloud Aerosol Lidar for Global Scale Observations of the Ocean-Land-Atmosphere System – CALIGOLA, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5644, https://doi.org/10.5194/egusphere-egu22-5644, 2022.

08:48–08:54
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EGU22-7336
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ECS
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On-site presentation
Julian Steinheuer, Frank Beyrich, Carola Detring, Stephanie Fiedler, Petra Friederichs, and Ulrich Löhnert

The evolution of wind gusts is difficult to observe as gusts are short-lived and small-scale phenomena. They occur with certain weather configurations (e.g. fronts, cold pools) and may already differ very locally. The question arises if individual gust observations can be taken as representative of their surroundings or if significant differences can already be apparent on the meso-gamma scale (2-20 km). Within the Field Experiment on Sub-Mesoscale Spatio-Temporal Variability in Lindenberg (FESSTVaL) different phenomena in the atmospheric boundary layer are studied with a variety of measurement instruments. This involved installing three StreamLine DWL systems from Halo Photonics at a distance of 6 km apart from each other. DWLs allow the retrieval of wind vector profiles and offer an alternative to classic meteorological tower observations, since they can be flexibly deployed at any electrified site. However, short-lived gusts are more difficult to capture than a persistent mean wind. A wind vector has to be obtained from different radial velocity measurements that are made sequentially, which limits the achievable temporal resolution. Therefore, we have developed a new retrieval method for deriving wind measurements that is suitable for different scan configurations and different time resolutions respectively different numbers of radial velocities. A fast continuous scanning mode (CSM), that completes a full observation cycle within 3.4 seconds and measures about eleven radial Doppler velocities is a suitable DWL configuration for deriving wind gusts, as shown by comparisons with measurements of a sonic anemometer at 90.3 m a.g.l. on the meteorological tower in Falkenberg. The fast CSM configuration was operated on the DWLs during the summer months 2021 at the three different sites. Their surrounding area is predominantly flat farmland, minimizing topographic impacts. This set-up allows us to observe the spatial-temporal evolution of gusts at the meso-gamma scale. Examples will be presented that illustrate the variability of wind gusts as observed during FESSTVaL.

How to cite: Steinheuer, J., Beyrich, F., Detring, C., Fiedler, S., Friederichs, P., and Löhnert, U.: Sub-mesoscale evolution of spatial wind gust patterns measured with three Doppler lidars in a triangle configuration, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7336, https://doi.org/10.5194/egusphere-egu22-7336, 2022.

08:54–09:00
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EGU22-7792
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On-site presentation
Donato Summa, Paolo Di Girolamo, Gemine Vivone, Noemi Franco, D'amico Giuseppe, and Benedetto De Rosa

The atmospheric planetary boundary layer (ABL) represents the lower region of the atmosphere directly in contact with the earth's surface and strongly influenced by this surface. In this layer physical quantities such as flow velocity, temperature and humidity exhibit rapid fluctuations associated with turbulent motion and vertical mixing.

Characterization of the planetary boundary layer is of primary importance in a variety of fields such as weather forecasting, climate change modeling and air quality forecasting and therefore it is very important to determine it correctly. The structure of ABL can be complex and highly variable.  In this work different techniques to estimate the ABL height are compared. A first technique makes use of the pure rotational Raman lidar signals, which are strongly dependent on temperature. A second technique makes use of the  water vapor roto-vibrational Raman lidar signals in the lower troposphere. Further techniques based on the Morphological Image Processing Approach (MIPA) are also considered. In the present research work, we consider the measurements from the University of Basilicata Raman lidar system BASIL collected in the period 16-21 October 2012 in the frame of HyMex SOP1 [1,2,3].

References:

[1] Di Girolamo, P., R. Marchese, D. N. Whiteman, B. B. Demoz, Rotational Raman Lidar measurements of atmospheric temperature in the UV. Geophysical Research Letters, 31, L01106, ISSN: 0094-8276, doi: 10.1029/2003GL018342, 2004.

[2] Vivone, G., D'Amico G., Summa D., Lolli S., Amodeo A., Bortoli D., and Pappalardo G.. Atmospheric boundary layer height estimation from aerosol lidar: a new approach based on morphological image processing techniques Atmos. Chem. Phys., 21, 4249–4265, 2021 https://doi.org/10.5194/acp-21-4249-2021.

[3] Summa, D., P. Di Girolamo, D. Stelitano, and M. Cacciani, Characterization of the planetary boundary layer height and structure by Raman lidar: comparison of different approaches, Atmos. Meas. Tech., 6, 3515–3525, 2013, www.atmos-meas-tech.net/6/3515/2013/doi:10.5194/amt-6-3515-2013

How to cite: Summa, D., Di Girolamo, P., Vivone, G., Franco, N., Giuseppe, D., and De Rosa, B.: ABL determination by Raman lidar with different approaches in the frame of HyMeX SOP1, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7792, https://doi.org/10.5194/egusphere-egu22-7792, 2022.

09:00–09:06
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EGU22-7808
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ECS
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On-site presentation
Alexandre Baron, Valentin Duflot, Patrick Chazette, Marco Gaetani, Cyrille Flamant, Juan Cuesta, Guillaume Payen, Philippe Keckhut, and Philippe Goloub

In the southern hemisphere, the dry season from June to October coincides with the occurrence of significant fires especially located along the tropical belt in Africa and South America. This fire activity is an important source of aerosols in the tropical troposphere and results in smoke plumes transported across long distances toward area generally aerosol-free. The atmospheric composition over the Indian Ocean is often influenced by biomass burning plumes shaped by the synoptic atmospheric circulation with high pressure over southern Africa and the movement of westerly waves that may embedded cut-off lows. The propagation over the Indian Ocean is then dependent on the position of the Mascarene High. The meandering shape of the plumes is then associated with an aerosol atmospheric river (AAR). Such a phenomenon has been sampled by spaceborne lidars and spectro-radiometers, and even observed above La Réunion (21.1°S, 55.3°E) during September 2017 by a ground-based lidar and a sun-photometer. The Li1200, an operational lidar in the frame of the Atmospheric Physics Reunion Observatory (OPAR), recorded the passage of an AAR during two nights. These measurements allow us to derive both the vertical structures of the plume and some vertically resolved aerosol optical properties. This information was used to constrain Lagrangian modelling tools to identify the pathways and origins of the biomass burning plume. These results have been corroborated by the spaceborne observations of CALIOP and CATS, and the passive sensor MODIS. Reanalysis of ECMWF with atmospheric composition outputs from the Copernicus Atmosphere Monitoring Service (CAMS) supports the understanding of the synoptic conditions leading to the formation of this aerosol plume configuration. We will present our scientific approach and discuss the environmental impact of these AARs in the southwest Indian Ocean.

How to cite: Baron, A., Duflot, V., Chazette, P., Gaetani, M., Flamant, C., Cuesta, J., Payen, G., Keckhut, P., and Goloub, P.: Remote-sensing of aerosol atmospheric rivers over the southwest Indian Ocean in September 2017: origins, evolution and impacts, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7808, https://doi.org/10.5194/egusphere-egu22-7808, 2022.

09:06–09:12
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EGU22-8554
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Virtual presentation
Simone Lolli, Erica Dolinar, Jasper R. Lewis, James R. Campbell, and Ellsworth J. Welton

In this study, we present the results of 20 years of cirrus cloud optical and geometrical properties retrieved from lidar observations at NASA Goddard Flight Space Center, a permanent site of the Micropulse lidar network (MPLNET). In this research, moreover, we also focus on determining the consistency of lidar long-term measurements, i.e. assessing the Signal-To-Noise variation over the two decades and its relationship to detection sensitivity and/or the quality of the calibration procedure. Through this research, it is possible to assess how changes in optical and geometrical properties of the cirrus clouds over twenty years impacted the Earth-atmosphere radiative budget, both at the surface and at the top-of-the-atmosphere. This unique and unprecedented study is the first step in assessing how climate changes influence cirrus cloud formation and lifetime and their feedback to climate. The same analysis will be then carried out for all the MPLNET permanent observational sites deployed at global scale. 

How to cite: Lolli, S., Dolinar, E., Lewis, J. R., Campbell, J. R., and Welton, E. J.: Multi-year analysis on cirrus cloud optical and geometrical properties at Goddard Space Flight Center in the frame of the NASA MPLNET lidar network, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8554, https://doi.org/10.5194/egusphere-egu22-8554, 2022.

09:12–09:18
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EGU22-9144
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Presentation form not yet defined
Qiang Li and Silke Groß

Aviation affects the Earth’s radiation budget through a combination of multiply processes which warm the atmosphere. Linear contrails and contrail cirrus induced by water vapor and soot emissions from air traffic in the upper atmosphere are expected to contribute a large part of the climate impact of avation. Furthermore, contrails cause a significant increase in cirrus optical thickness as well as an indirect effect on the microphysical properties of naturally formed cirrus clouds. During the first lockdown in April 2020, air traffic over Europe was significantly reduced to about 80% compared to the year before. This unique situation provides a good opportunity to study the effect of air traffic on cirrus. Based on the analysis of the spaceborne lidar measurements with CALIPSO, we found a significant reduction in the particle linear depolarization ratio (PLDR) of cirrus clouds measured in April 2020 compared to the previous years 2014-2019 under normal conditions, especially at colder temperatuers (T < -50oC). However, we note that civil aviation over Europe before the COVID-19 pandemic (i.e., before March 2020) grew strongly in terms of CO2 emission and flight densities, e.g. on average by 233 MTon/year over Germany, over the past years (2010-2019, especially 2013-2019, source: EUROCONTROL). In order to study the aviation effects of cirrus properties in a longer period (with, of course, milder change in air traffic than the case due to the COVID lockdown), we further extend our analysis to all the observations from Mar. 2010 to Feb. 2020. We found a long-term trend of 0,0087/year (~2.4% per year) in PLDR for all the cirrus observations (day+night) and a trend of 0.0107/year for only the day-time observations at altitudes between 6 and 13 km. In addition, seasonal variations of PLDR are also drived showing higher PLDR-values in winter than in summer for all the measurements as well as for the measurements in different altitude bins. In the end, we compared the background meteorological conditions including the ambient temperature, relative humidity, and vertical updrafts determined with ECMWF and analyzed the correlation between PLDR and the corresponding CO2 emissions as a proxy of air traffic densities.

Key words: CALIPSO; Cirrus cloud; Lidar; Depolarization ratio; PLDR; COVID-19

How to cite: Li, Q. and Groß, S.: Aviation-induced changes in cirrus clouds over Europe during COVID-19 and in a ten-year period before COVID-19 , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9144, https://doi.org/10.5194/egusphere-egu22-9144, 2022.

09:18–09:24
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EGU22-9407
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ECS
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Virtual presentation
Alessia Sannino, Salvatore Amoruso, Riccardo Damiano, Simona Scollo, pasquale Sellitto, and Antonella Boselli

Studies on the spatio-temporal characterization of microphysical and optical properties of atmospheric aerosol are of particular interest for their impacts on life cycle. Unfortunately, large uncertainties govern these studies because of the wide variability of the components which characterize the aerosol, especially when several sources concur in the observations. This is exactly what happens over the Central Mediterranean where particles of different nature and typology, produced by local sources or long-range transport phenomena from natural and anthropogenic sources, coexist frequently in the aerosol layers. Among these contributions, a special mention deserves the volcanic activity, since Mediterranean area hosts numerous active volcanoes, like Mount Etna, in Italy, whose degassing and explosive activities have a strong impact on the atmospheric aerosol composition. In this work we present the results from the Etna paroxysmal event occurred  in February 21st - 26th, 2021 and observed in the Naples area in coexistence with Saharan dust transport. The event has been characterized by the ACTRIS (Aerosol, Clouds and Trace Gases Research Infrastructure) observation station of the University of Naples “Federico II” by combining lidar, sunphotometer and satellite data. Back-trajectories and volcanic plume dispersion simulations were also performed in order to better distinguish geometrical, optical and microphysical properties of the atmospheric aerosol. From our analysis, spatio-temporal information of the two main aerosol components in terms of their optical  and microphysical proprieties were clearly identified. In particular, starting from lidar data, the particle size distributions were retrieved at desired altitudes using a novel inversion approach based on a new Monte Carlo algorithm. Interestingly, when integrated over the range on the observation column, the experimental findings result in good agreement with the data provided by the sunphotometer.

How to cite: Sannino, A., Amoruso, S., Damiano, R., Scollo, S., Sellitto, P., and Boselli, A.: Observation of Simultaneous Etna Volcanic aerosol and Desert Dust aerosol over Naples: an experimental test for a new lidar inversion algorithms , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9407, https://doi.org/10.5194/egusphere-egu22-9407, 2022.

09:24–09:30
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EGU22-10130
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ECS
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Presentation form not yet defined
Transformation of the shape and spectrum of femtosecond pulses during propagation in gaseous media
(withdrawn)
Katsiaryna Cidorkina, Natalia Dorozhko, Egor Suschenko, Alexander Svetashev, and Leonid Turishev
09:30–09:36
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EGU22-11817
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ECS
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Virtual presentation
Noemi Franco, Paolo Di Girolamo, Donato Summa, Benedetto De Rosa, Andreas Behrendt, and Volker Wulfmeyer

The Atmospheric Thermodynamic LidAr in Space (ATLAS) is a mission concept proposed to the European Space Agency in the frame of “Earth Explorer-11 Mission Ideas” Call by a team of researchers, with the aim to develop the first Raman Lidar in space capable to measure simultaneously atmospheric temperature and water vapour mixing ratio profiles with high temporal and spatial resolutions. Accurate measurements of these profiles are essential to understand water and energy cycles, as well as the prediction of extreme events, that nowadays still show huge deficiencies on all temporal and spatial scales (1). Such measurements would have a revolutionary impact on our understanding of the Earth system and would close the gap in our observational capabilities from the surface to the lower troposphere.

The specifications of the different lidar sub-system, as well as the expected capability to provide measurements with high temporal and spatial resolution in the low and middle troposphere, have already been established with an analytical simulation model (2,3). These simulations considered different atmospheric models and conditions to estimate the statistical uncertainty on water vapour and temperature measurements. New studies have been now performed to estimate the performances along several dawn-dusk orbits. An end-to-end simulator has been developed and used to estimate the statistical and systematic uncertainties. The input data, comprehensive of thermodynamic and optical parameters, have been extracted from the GEOS-5 Nature Run and have been chosen to perform simulations with different solar zenith angles and therefore different background contributions. The model includes information on cloud fraction and optical thickness, so it was also possible to consider the performances in cloudy conditions. The simulations show promising results, both in clear and cloudy conditions and with different background contributions. A comprehensive study of the assessed performances will be presented at the conference.

The simulated measurements obtained from the simulator will be also used as input observations in the Weather Research and Forecasting model (WRF). The aim is to estimate the impact of global measurements from a space-borne Raman Lidar in terms of skill-scores, obtained by the comparison of the weather forecast output with and without the assimilation of the simulated lidar data.

1 - Wulfmeyer, Hardesty, Turner, Behrendt, Cadeddu, Di Girolamo, et al. A review of the remote sensing of lower tropospheric thermodynamic profiles and its indispensable role for the understanding and the simulation of water and energy cycles. Reviews of Geophysics. 2015; 53(3):819–95.

2 - Di Girolamo, Behrendt, Wulfmeyer. Space-borne profiling of atmospheric thermodynamic variables with Raman lidar: performance simulations. Opt Express,OE. 2 aprile 2018; 26(7):8125–61.

3 - Di Girolamo, Behrendt, Wulfmeyer. Spaceborne profiling of atmospheric temperature and particle extinction with pure rotational Raman lidar and of relative humidity in combination with differential absorption lidar: performance simulations. Appl Opt, AO. 10 aprile 2006; 45(11):2474–94.

How to cite: Franco, N., Di Girolamo, P., Summa, D., De Rosa, B., Behrendt, A., and Wulfmeyer, V.: Performance assessment of the space-borne Raman Lidar ATLAS – Atmospheric Thermodynamic LidAr in Space, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11817, https://doi.org/10.5194/egusphere-egu22-11817, 2022.

09:36–09:42
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EGU22-12076
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ECS
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Virtual presentation
Jonas Hamperl, Patrick Chazette, Julien Totems, Jean-Baptiste Dherbecourt, Jean-Michel Melkonian, Philippe Nicolas, Myriam Raybaut, Aurélien Clémençon, Nicolas Geyskens, Pascal Geneau, Cyrille Flamant, Daniele Zannoni, Harald Sodemann, Hans Christian Steen-Larsen, Anne Monod, Amandine Durand, Sylvain Ravier, and Alfons Schwarzenboeck

The Lidar Emitter and Multispecies greenhouse gases Observation iNstrument (LEMON) objective is the development and test of a new Differential Absorption Lidar (DIAL) sensor concept for greenhouse gases and water vapor for spaceborne, airborne or ground-based measurements. The innovative instrument is based on a versatile transmitter. The concept of the measurement was recently preliminarily tested for water vapor in a co-dedicated field campaign from 13 to 24 September 2021 over the Aubenas airfield (France, 44° 32' N 4° 22' E). This campaign was also an opportunity to test different approaches for the measurement of the vertical water vapor profile using classical meteorological probes embarked on meteorological balloons and on an airplane, a vibrational Raman lidar WALI (Weather Atmospheric LIdar), a cavity ring-down spectrometer (CRDS) and of course a first version of the LEMON lidar named WaVIL (Water Vapor and Isotope Lidar). The field campaign involved an instrumented van with two lidars and three ULAs carrying various payloads: a backscatter Rayleigh-Mie lidar to identify atmospheric structures from the local to regional scales, a CRDS for water vapor isotope measurements and in situ samplers to characterize cloud-related forcing on atmospheric water vapor concentrations. The measurement strategy adopted made it possible to follow the evaporation of water vapor throughout the course of a thunderstorm and to sample an intrusion of dry air from high altitudes. It also provided initial answers as to the potential of the WaViL instrument for measuring the main isotope of water vapor and its secondary isotope HDO. The measurement campaign will be presented, as well as the first associated results.

How to cite: Hamperl, J., Chazette, P., Totems, J., Dherbecourt, J.-B., Melkonian, J.-M., Nicolas, P., Raybaut, M., Clémençon, A., Geyskens, N., Geneau, P., Flamant, C., Zannoni, D., Sodemann, H., Steen-Larsen, H. C., Monod, A., Durand, A., Ravier, S., and Schwarzenboeck, A.: Demonstration of water vapor and Isotopes measurement from lidar using a multi-platform, multi-instrumental approach, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12076, https://doi.org/10.5194/egusphere-egu22-12076, 2022.

09:42–09:48
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EGU22-12079
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ECS
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Highlight
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Virtual presentation
Lev Labzovskii, Gerd-Jan van Zadelhoff, David Donovan, Jos De Kloe, and Damien Josset

The Aeolus mission offers unique opportunities for lidar surface returns (LSR) applications considering its incidence angle (~37.5o) and the operated wavelength (~355 nm). Previous Aeolus-oriented studies have indicated that the contrast between LSR over dark and bright surfaces is expected to be particularly pronounced at 355 nm. We evaluated this surmise by comparing new LSR estimates from novel Aeolus prototype processor (using an optimal estimation approach) with various types of land for the Intensive Observation Period of Aeolus (September 2019) and an additional period during the same year. We discerned a very clear LSR gradient between the signal from water (mostly weak, but variable) and the signal from land (mostly strong), whereas the strongest LSR was found over white surfaces (ice or snow). Moreover, the sensitivity of LSR to the type of surface was also identified as the gradient between the brightest surfaces (snow/ice, sparse vegetation) and the dark surfaces (herbaceous forest, mangrove, wetland) was significant. Specifically, besides Antarctica and Greenland, the strongest returns over land were reported over the snow-covered areas of Tibet and Andes, followed by the arid areas of Northern America, Northern Africa and Middle East. Notably, the LSR from water was not always low as the average LSR estimate over water exhibited the strongest variability (~0.001 – 0.042 sr-1) and yielded most statistical outliers. The application of sea ice mask from MERRA-2 model revealed that most strong LSR cases over water were associated with the undetected ice. The masking of detected ice has resulted in the dramatic reduction of the average LSR over water. As a result, the related LSR variability over water was dwindled by the factor of ~10 down to ~0.001 – 0.004 sr-1 and >95% of outliers disappeared. Our findings about the sensitivity of Aeolus surface returns to the type of surface are beneficial because statistically robust LSR estimates over ocean lay the foundation for the Aeolus LSR-based Aerosol Optical Depth (AOD) retrieval over ocean. This retrieval can be established based on the fundamental link between LSR, near-surface wind speed and AOD over sea surface.

How to cite: Labzovskii, L., van Zadelhoff, G.-J., Donovan, D., De Kloe, J., and Josset, D.: How sensitive are Aeolus Lidar Surface Returns (LSR) to the types of surface? Insights for LSR-based retrieval of AOD over ocean by using Aeolus., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12079, https://doi.org/10.5194/egusphere-egu22-12079, 2022.

09:48–09:54
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EGU22-12960
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Virtual presentation
Benedetto De Rosa, Lucia Mona, Aldo Amodeo, Nikos Papagiannopolos, Donato Summa, Michalis Mytilinaios, and Igor Veselovskii

On 14 August 2021 a forest fire started at 16:00 U.T.C. were observed by the Lidar Raman MUSA and the CIMEL 318 sun-photometer of CNR IMAA of Potenza located at 1 km from the fire. Due to proximity to only 1 km this measurements represents an important case of study. Measurements carried out by the Lidar MUSA  reveal the presence of a smoke layer below 2.7 km  from 22:27 to 23:19 the. The optical parameters derived are backscattering at 355, 532 and 1064 nm, extinction at 355 and 532 nm, Lidar ratios at 355 and 532 nm wavelengths, Ångström exponents,  and particle and volume depolarization at 532 nm. Results indicate a low absorption  an high scattering of fire particles.

Lidar ratio are 40 sr at 355 and 38 at 532, particle depolarization is 0.025 and Ångström exponents are approx 1.5 for all wavelengths.

To derive microphysical properties are used The inversion of 3 β + 2 α. The values of surface concentration is 410 µm2 cm-3, the volume concentration is 21 µm3 cm-3and numeric density is  2300 cm-3. The size distribution is  bi-modal distribution with a peak at 0.13 µm. The effective radius is 0.15 µm. The single scattering albedo at 355, 532 and 1064 are 0.96, the real and the imaginary part of the refractive index are respectively 1.58 and 0.006.

Therefore, particles are small, spherical and weakly absorbing probably due to a minimum contribution of black carbon

The CIMEL 318 sun photometer measurements at 5:34 U.T.C confirm the results of MUSA.

How to cite: De Rosa, B., Mona, L., Amodeo, A., Papagiannopolos, N., Summa, D., Mytilinaios, M., and Veselovskii, I.: Extremely fresh biomass burning aerosol observed in Potenza by multiwavelength Raman Lidar MUSA and the CIMEL 318 sun-photometer., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12960, https://doi.org/10.5194/egusphere-egu22-12960, 2022.