Bibliografie tematiche / Aerosol microphysical properties

Letteratura scientifica selezionata sul tema "Aerosol microphysical properties"

Autore: Grafiati

Pubblicato: 22 giugno 2024

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Articoli di riviste sul tema "Aerosol microphysical properties":

Zheng, Xiaojian, Baike Xi, Xiquan Dong, Timothy Logan, Yuan Wang e Peng Wu. "Investigation of aerosol–cloud interactions under different absorptive aerosol regimes using Atmospheric Radiation Measurement (ARM) southern Great Plains (SGP) ground-based measurements". Atmospheric Chemistry and Physics 20, n. 6 (24 marzo 2020): 3483–501. http://dx.doi.org/10.5194/acp-20-3483-2020.

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Abstract. The aerosol indirect effect on cloud microphysical and radiative properties is one of the largest uncertainties in climate simulations. In order to investigate the aerosol–cloud interactions, a total of 16 low-level stratus cloud cases under daytime coupled boundary-layer conditions are selected over the southern Great Plains (SGP) region of the United States. The physicochemical properties of aerosols and their impacts on cloud microphysical properties are examined using data collected from the Department of Energy Atmospheric Radiation Measurement (ARM) facility at the SGP site. The aerosol–cloud interaction index (ACIr) is used to quantify the aerosol impacts with respect to cloud-droplet effective radius. The mean value of ACIr calculated from all selected samples is 0.145±0.05 and ranges from 0.09 to 0.24 at a range of cloud liquid water paths (LWPs; LWP=20–300 g m−2). The magnitude of ACIr decreases with an increasing LWP, which suggests a diminished cloud microphysical response to aerosol loading, presumably due to enhanced condensational growth processes and enlarged particle sizes. The impact of aerosols with different light-absorbing abilities on the sensitivity of cloud microphysical responses is also investigated. In the presence of weak light-absorbing aerosols, the low-level clouds feature a higher number concentration of cloud condensation nuclei (NCCN) and smaller effective radii (re), while the opposite is true for strong light-absorbing aerosols. Furthermore, the mean activation ratio of aerosols to CCN (NCCN∕Na) for weakly (strongly) absorbing aerosols is 0.54 (0.45), owing to the aerosol microphysical effects, particularly the different aerosol compositions inferred by their absorptive properties. In terms of the sensitivity of cloud-droplet number concentration (Nd) to NCCN, the fraction of CCN that converted to cloud droplets (Nd∕NCCN) for the weakly (strongly) absorptive regime is 0.69 (0.54). The measured ACIr values in the weakly absorptive regime are relatively higher, indicating that clouds have greater microphysical responses to aerosols, owing to the favorable thermodynamic condition. The reduced ACIr values in the strongly absorptive regime are due to the cloud-layer heating effect induced by strong light-absorbing aerosols. Consequently, we expect larger shortwave radiative cooling effects from clouds in the weakly absorptive regime than those in the strongly absorptive regime.

Wandinger, Ulla, Athena Augusta Floutsi, Holger Baars, Moritz Haarig, Albert Ansmann, Anja Hünerbein, Nicole Docter et al. "HETEAC – the Hybrid End-To-End Aerosol Classification model for EarthCARE". Atmospheric Measurement Techniques 16, n. 10 (25 maggio 2023): 2485–510. http://dx.doi.org/10.5194/amt-16-2485-2023.

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Abstract. The Hybrid End-To-End Aerosol Classification (HETEAC) model for the Earth Clouds, Aerosols and Radiation Explorer (EarthCARE) mission is introduced. The model serves as the common baseline for the development, evaluation, and implementation of EarthCARE algorithms. It guarantees the consistency of different aerosol products from the multi-instrument platform and facilitates the conformity of broad-band optical properties needed for EarthCARE radiative-closure assessments. While the hybrid approach ensures that the theoretical description of aerosol microphysical properties is consistent with the optical properties of the measured aerosol types, the end-to-end model permits the uniform representation of aerosol types in terms of microphysical, optical, and radiative properties. Four basic aerosol components with prescribed microphysical properties are used to compose various natural and anthropogenic aerosols of the troposphere. The components contain weakly and strongly absorbing fine-mode and spherical and non-spherical coarse-mode particles and thus are representative for pollution, smoke, sea salt, and dust, respectively. Their microphysical properties are selected such that good coverage of the observational phase space of intensive, i.e., concentration-independent, optical aerosol properties derived from EarthCARE measurements is obtained. Mixing rules to calculate optical and radiative properties of any aerosol blend composed of the four basic components are provided. Applications of HETEAC in the generation of test scenes, the development of retrieval algorithms for stand-alone and synergistic aerosol products from EarthCARE's atmospheric lidar (ATLID) and multi-spectral imager (MSI), and for radiative-closure assessments are introduced. Finally, the implications of simplifying model assumptions and possible improvements are discussed, and conclusions for future validation and development work are drawn.

Fan, Jiwen, Yuan Wang, Daniel Rosenfeld e Xiaohong Liu. "Review of Aerosol–Cloud Interactions: Mechanisms, Significance, and Challenges". Journal of the Atmospheric Sciences 73, n. 11 (6 ottobre 2016): 4221–52. http://dx.doi.org/10.1175/jas-d-16-0037.1.

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Abstract Over the past decade, the number of studies that investigate aerosol–cloud interactions has increased considerably. Although tremendous progress has been made to improve the understanding of basic physical mechanisms of aerosol–cloud interactions and reduce their uncertainties in climate forcing, there is still poor understanding of 1) some of the mechanisms that interact with each other over multiple spatial and temporal scales, 2) the feedbacks between microphysical and dynamical processes and between local-scale processes and large-scale circulations, and 3) the significance of cloud–aerosol interactions on weather systems as well as regional and global climate. This review focuses on recent theoretical studies and important mechanisms on aerosol–cloud interactions and discusses the significances of aerosol impacts on radiative forcing and precipitation extremes associated with different cloud systems. The authors summarize the main obstacles preventing the science from making a leap—for example, the lack of concurrent profile measurements of cloud dynamics, microphysics, and aerosols over a wide region on the observation side and the large variability of cloud microphysics parameterizations resulting in a large spread of modeling results on the modeling side. Therefore, large efforts are needed to escalate understanding. Future directions should focus on obtaining concurrent measurements of aerosol properties and cloud microphysical and dynamic properties over a range of temporal and spatial scales collected over typical climate regimes and closure studies, as well as improving understanding and parameterizations of cloud microphysics such as ice nucleation, mixed-phase properties, and hydrometeor size and fall speed.

Nugent, Alison D., Campbell D. Watson, Gregory Thompson e Ronald B. Smith. "Aerosol Impacts on Thermally Driven Orographic Convection". Journal of the Atmospheric Sciences 73, n. 8 (25 luglio 2016): 3115–32. http://dx.doi.org/10.1175/jas-d-15-0320.1.

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Abstract Observations from the Dominica Experiment (DOMEX) field campaign clearly show aerosols having an impact on cloud microphysical properties in thermally driven orographic clouds. It is hypothesized that when convection is forced by island surface heating, aerosols from the mostly forested island surface are lofted into the clouds, resulting in the observed high concentration of aerosols and the high concentration of small cloud droplets. When trying to understand the impact of these surface-based aerosols on precipitation, however, observed differences in cloud-layer moisture add to the complexity. The WRF Model with the aerosol-aware Thompson microphysics scheme is used to study six idealized scenarios of thermally driven island convection: with and without a surface aerosol source, with a relatively dry cloud layer and with a moist cloud layer, and with no wind and with a weak background wind. It is found that at least a weak background wind is needed to ensure Dominica-relevant results and that the effect of cloud-layer moisture on cloud and precipitation formation dominates over the effect of aerosol. The aerosol impact is limited by the dominance of precipitation formation through accretion. Nevertheless, in order to match observed cloud microphysical properties and precipitation, both a relatively dry cloud layer and a surface aerosol source are needed. The impact of a surface aerosol source on precipitation is strongest when the environment is not conducive to cloud growth.

Milinevsky, G., Ya Yatskiv, O. Degtyaryov, I. Syniavskyi, Yu Ivanov, A. Bovchaliuk, M. Mishchenko, V. Danylevsky, M. Sosonkin e V. Bovchaliuk. "Remote sensing of aerosol in the terrestrial atmosphere from space: new missions". Advances in Astronomy and Space Physics 5, n. 1 (2015): 11–16. http://dx.doi.org/10.17721/2227-1481.5.11-16.

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The distribution and properties of atmospheric aerosols on a global scale are not well known in terms of determination of their effects on climate. This mostly is due to extreme variability of aerosol concentrations, properties, sources, and types. Aerosol climate impact is comparable to the effect of greenhouse gases, but its influence is more difficult to measure, especially with respect to aerosol microphysical properties and the evaluation of anthropogenic aerosol effect. There are many satellite missions studying aerosol distribution in the terrestrial atmosphere, such as MISR/Terra, OMI/Aura, AVHHR, MODIS/Terra and Aqua, CALIOP/CALIPSO. To improve the quality of data and climate models, and to reduce aerosol climate forcing uncertainties, several new missions are planned. The gap in orbital instruments for studying aerosol microphysics has arisen after the Glory mission failed during launch in 2011. In this review paper, we describe several planned aerosol space missions, including the Ukrainian project Aerosol-UA that obtains data using a multi-channel scanning polarimeter and wide-angle polarimetric camera. The project is designed for remote sensing of the aerosol microphysics and cloud properties on a global scale.

Vanderlei Martins, J., A. Marshak, L. A. Remer, D. Rosenfeld, Y. J. Kaufman, R. Fernandez-Borda, I. Koren, V. Zubko e P. Artaxo. "Remote sensing the vertical profile of cloud droplet effective radius, thermodynamic phase, and temperature". Atmospheric Chemistry and Physics Discussions 7, n. 2 (30 marzo 2007): 4481–519. http://dx.doi.org/10.5194/acpd-7-4481-2007.

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Abstract. Cloud-aerosol interaction is no longer simply a radiative problem, but one affecting the water cycle, the weather, and the total energy balance including the spatial and temporal distribution of latent heat release. Information on the vertical distribution of cloud droplet microphysics and thermodynamic phase as a function of temperature or height, can be correlated with details of the aerosol field to provide insight on how these particles are affecting cloud properties and its consequences to cloud lifetime, precipitation, water cycle, and general energy balance. Unfortunately, today's experimental methods still lack the observational tools that can characterize the true evolution of the cloud microphysical, spatial and temporal structure in the cloud droplet scale, and then link these characteristics to environmental factors and properties of the cloud condensation nuclei. Here we propose and demonstrate a new experimental approach (the cloud scanner instrument) that provides the microphysical information missed in current experiments and remote sensing options. Cloud scanner measurements can be performed from aircraft, ground, or satellite by scanning the side of the clouds from the base to the top, providing us with the unique opportunity of obtaining snapshots of the cloud droplet microphysical and thermodynamic states as a function of height and brightness temperature in clouds at several development stages. The brightness temperature profile of the cloud side can be directly associated with the thermodynamic phase of the droplets to provide information on the glaciation temperature as a function of different ambient conditions, aerosol concentration, and type. An aircraft prototype of the cloud scanner was built and flew in a field campaign in Brazil. The CLAIM-3D (3-Dimensional Cloud Aerosol Interaction Mission) satellite concept proposed here combines several techniques to simultaneously measure the vertical profile of cloud microphysics, thermodynamic phase, brightness temperature, and aerosol amount and type in the neighborhood of the clouds. The wide wavelength range, and the use of mutli-angle polarization measurements proposed for this mission allow us to estimate the availability and characteristics of aerosol particles acting as cloud condensation nuclei, and their effects on the cloud microphysical structure. These results can provide unprecedented details on the response of cloud droplet microphysics to natural and anthropogenic aerosols in the size scale where the interaction really happens.

Martins, J. V., A. Marshak, L. A. Remer, D. Rosenfeld, Y. J. Kaufman, R. Fernandez-Borda, I. Koren, A. L. Correia, V. Zubko e P. Artaxo. "Remote sensing the vertical profile of cloud droplet effective radius, thermodynamic phase, and temperature". Atmospheric Chemistry and Physics 11, n. 18 (16 settembre 2011): 9485–501. http://dx.doi.org/10.5194/acp-11-9485-2011.

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Abstract. Cloud-aerosol interaction is a key issue in the climate system, affecting the water cycle, the weather, and the total energy balance including the spatial and temporal distribution of latent heat release. Information on the vertical distribution of cloud droplet microphysics and thermodynamic phase as a function of temperature or height, can be correlated with details of the aerosol field to provide insight on how these particles are affecting cloud properties and their consequences to cloud lifetime, precipitation, water cycle, and general energy balance. Unfortunately, today's experimental methods still lack the observational tools that can characterize the true evolution of the cloud microphysical, spatial and temporal structure in the cloud droplet scale, and then link these characteristics to environmental factors and properties of the cloud condensation nuclei. Here we propose and demonstrate a new experimental approach (the cloud scanner instrument) that provides the microphysical information missed in current experiments and remote sensing options. Cloud scanner measurements can be performed from aircraft, ground, or satellite by scanning the side of the clouds from the base to the top, providing us with the unique opportunity of obtaining snapshots of the cloud droplet microphysical and thermodynamic states as a function of height and brightness temperature in clouds at several development stages. The brightness temperature profile of the cloud side can be directly associated with the thermodynamic phase of the droplets to provide information on the glaciation temperature as a function of different ambient conditions, aerosol concentration, and type. An aircraft prototype of the cloud scanner was built and flew in a field campaign in Brazil. The CLAIM-3D (3-Dimensional Cloud Aerosol Interaction Mission) satellite concept proposed here combines several techniques to simultaneously measure the vertical profile of cloud microphysics, thermodynamic phase, brightness temperature, and aerosol amount and type in the neighborhood of the clouds. The wide wavelength range, and the use of multi-angle polarization measurements proposed for this mission allow us to estimate the availability and characteristics of aerosol particles acting as cloud condensation nuclei, and their effects on the cloud microphysical structure. These results can provide unprecedented details on the response of cloud droplet microphysics to natural and anthropogenic aerosols in the size scale where the interaction really happens.

Meland, B. S., X. Xu, D. K. Henze e J. Wang. "Assessing remote polarimetric measurement sensitivities to aerosol emissions using the geos-chem adjoint model". Atmospheric Measurement Techniques 6, n. 12 (10 dicembre 2013): 3441–57. http://dx.doi.org/10.5194/amt-6-3441-2013.

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Abstract. Uncertainties in aerosol sources, microphysical properties, and global distributions undermine efforts to evaluate the radiative impacts of atmospheric aerosols. In this work, we investigate the feasibility of using remote polarimetric measurements for constraining aerosol and aerosol precursor emissions in light of these uncertainties. A model that incorporates a radiative transfer model with forward and adjoint chemical transport models has been applied to quantify the sensitivity of the reflectance at the top of atmosphere over land to aerosol emissions and microphysical properties. A set of simulated satellite observations, one intensity based and one capable of polarimetric measurements, are used to illustrate differences in the assimilation potential between the two. It is found that the sensitivity of the polarized reflectance to aerosol and aerosol precursor emissions tends to be significantly higher than that of the intensity for cases of non-absorbing aerosols. This is true even when the polarimetric sampling scheme is spatially sparser than that of the intensity sampling. This framework allows us to quantify upper limits on the uncertainties in the aerosol microphysical properties for which a 50% change in aerosol emissions is detectable using these simulated observations. It was found that although typical current remote sensing instrumentation provides retrievals of the refractive index and effective radius with accuracies within acceptable limits to detect a 50% change in emissions, retrievals of the effective variance contain uncertainties too large to detect these changes in emissions. These results may guide new applications of polarimetric measurements to constrain aerosol sources, and thus reduce uncertainty in our broader understanding of the impacts of aerosols on climate.

Meland, B. S., X. Xu, D. K. Henze e J. Wang. "Assessing remote polarimetric measurements sensitivities to aerosol emissions using the GEOS-Chem adjoint model". Atmospheric Measurement Techniques Discussions 6, n. 3 (19 giugno 2013): 5447–93. http://dx.doi.org/10.5194/amtd-6-5447-2013.

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Abstract. Uncertainties in aerosol sources, microphysical properties, and global distributions undermine efforts to evaluate the radiative impacts of atmospheric aerosols. In this work, we investigate the feasibility of using remote polarimetric measurements for constraining aerosol and aerosol precursor emissions in light of these uncertainties. A model that incorporates a radiative transfer model with forward and adjoint chemical transport models has been applied to quantify the sensitivity of the reflectance at the top of atmosphere to aerosol emissions and microphysical properties. A set of simulated satellite observations, one intensity based and one capable of polarimetric measurements, are used to illustrate differences in the assimilation potential between the two. It is found that the sensitivity of the polarized reflectance to aerosol and aerosol precursor emissions tends to be significantly higher than that of the intensity for cases of non-absorbing aerosols. This is true even when the polarimetric sampling scheme is spatially sparser than that of the intensity sampling. This framework allows us to quantify upper limits on the uncertainties in the aerosol microphysical properties for which a 50% change in aerosol emissions is detectable using these simulated observations. It was found that although typical current remote sensing instrumentation provides retrievals of the refractive index and effective radius with accuracies within acceptable limits to detect a 50% change in emissions, retrievals of the effective variance contain uncertainties too large to detect these changes in emissions. These results may guide new applications of polarimetric measurements to constrain aerosol sources, and thus reduce uncertainty in our broader understanding of the impacts of aerosols on climate.

Kipling, Zak, Laurent Labbouz e Philip Stier. "Global response of parameterised convective cloud fields to anthropogenic aerosol forcing". Atmospheric Chemistry and Physics 20, n. 7 (17 aprile 2020): 4445–60. http://dx.doi.org/10.5194/acp-20-4445-2020.

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Abstract. The interactions between aerosols and convective clouds represent some of the greatest uncertainties in the climate impact of aerosols in the atmosphere. A wide variety of mechanisms have been proposed by which aerosols may invigorate, suppress or change the properties of individual convective clouds, some of which can be reproduced in high-resolution limited-area models. However, there may also be mesoscale, regional or global adjustments which modulate or dampen such impacts which cannot be captured in the limited domain of such models. The Convective Cloud Field Model (CCFM) provides a mechanism to simulate a population of convective clouds, complete with microphysics and interactions between clouds, within each grid column at resolutions used for global climate modelling, so that a representation of the microphysical aerosol response within each parameterised cloud type is possible. Using CCFM within the global aerosol–climate model ECHAM–HAM, we demonstrate how the parameterised cloud field responds to the present-day anthropogenic aerosol perturbation in different regions. In particular, we show that in regions with strongly forced deep convection and/or significant aerosol effects via large-scale processes, the changes in the convective cloud field due to microphysical effects are rather small; however in a more weakly forced regime such as the Caribbean, where large-scale aerosol effects are small, a signature of convective invigoration does become apparent.

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Tesi sul tema "Aerosol microphysical properties":

Hamburger, Thomas. "Aerosol microphysical properties during anticyclonic flow conditions over Europe". Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-127766.

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Wurl, Daniela. "Optimal Estimation Retrieval of Aerosol Microphysical Properties in the Lower Stratosphere from SAGE II Satellite Observations". Thesis, University of Canterbury. Physics and Astronomy, 2007. http://hdl.handle.net/10092/1533.

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A new retrieval algorithm has been developed based on the Optimal Estimation (OE) approach, which retrieves lognormal aerosol size distribution parameters from multiwavelength aerosol extinction data, as measured by the Stratospheric Aerosol and Gas Experiment (SAGE) II in the lower stratosphere. Retrieving these aerosol properties becomes increasingly more difficult under aerosol background conditions, when tiny particles (« 0.1 µm) prevail, to which the experiment is nearly or entirely insensitive. A successful retrieval algorithm must then be able (a) to fill the 'blind spot' with suitable information about the practically invisible particles, and (b) to identify 'the best' of many possible solutions. The OE approach differs from other previously used aerosol retrieval techniques by taking a statistical approach to the multiple solution problem, in which the entire range of possible solutions are considered (including the smallest particles) and characterized by probability density functions. The three main parts of this thesis are (1) the development of the new OE retrieval algorithm, (2) the validation of this algorithm on the basis of synthetic extinction data, and (3) application of the new algorithm to SAGE II measurements of stratospheric background aerosol. The validation results indicate that the new method is able to retrieve the particle size of typical background aerosols reasonably well, and that the retrieved uncertainties are a good estimate of the true errors. The derived surface area densities (A), and volume densities (V ) tend to be closer to the correct solutions than the directly retrieved number density (N), median radius (R), and lognormal distribution width (S). Aerosol properties as retrieved from SAGE II measurements (recorded in 1999) are observed to be close to correlative in situ data. In many cases the OE and in situ data agree within the (OE and/or the in situ ) uncertainties. The retrieved error estimates are of the order of 69% (σN), 33% (σR), 14% (σS), 23% (σA), 12% (σV), and 13% (σReff ). The OE number densities are generally larger, and the OE median particle sizes are generally smaller than those N and R retrieved by Bingen et al. (2004a), who suggest that their results underestimate (N) or overestimate (R) correlative in situ data due to the 'small particle problem'. The OE surface area estimates are generally closer to correlative in situ profiles (courtesy of T. Deshler, University of Wyoming), and larger than Principal Component Analysis (PCA) retrieval solutions of A (courtesy of L. W. Thomason, NASA LaRC) that have been observed to underestimate correlative in situ data by 40-50%. These observations suggest that the new OE retrieval algorithm is a successful approach to the aerosol retrieval problem, which is able to add to the current knowledge by improving current estimates of aerosol properties in the lower stratosphere under low aerosol loading conditions.

Wagner, Janet. "Microphysical aerosol properties retrieved from combined lidar and sun photometer measurements". Master's thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-99830.

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To assess information about the optical, microphysical, and radiative properties of aerosol particles the lidar technique and sun photometers are commonly used. Information that result from both lidar and sun photometer data can provide a distinct image of the vertical aerosol properties. The algorithm developed at the Institute of Physics of the National Academy of Science of Belarus (IPNASB) uses lidar measurements at the three wavelengths 355, 532, and 1064 nm and mean backscatter and extinction coefficients retrieved from radiometric data to obtain profiles of fine-mode and coarse-mode concentrations. Within the master thesis the IPNASB algorithm was tested for specific aerosol situations. Three cases are considered representing Saharan dust, smoke and industrial aerosol from East Europe, and volcanic aerosol from the Eyjafjallajokull eruption. The retrieved microphysical aerosol properties are in good to acceptable agreement with findings of well-established methods.

Schmidt, Jörg. "Dual-field-of-view Raman lidar measurements of cloud microphysical properties". Doctoral thesis, Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-150408.

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Im Rahmen der vorliegenden Arbeit wurde eine neuartige Lidartechnik in ein leistungsstarkes Lidar-System implementiert. Mit Hilfe des realisierten Aufbaus wurden Aerosol-Wolken-Wechselwirkungen in Flüssigwasserwolken über Leipzig untersucht. Die angewandte Messmethode beruht auf der Detektion von Licht, das an Wolkentröpfchen mehrfach in Vorwärtsrichtung gestreut und an Stickstoffmolekülen inelastisch zurückgestreut wurde. Dabei werden zwei Gesichtsfelder unterschiedlicher Größe verwendet. Ein Vorwärtsiterations-Algorithmus nutzt die gewonnenen Informationen zur Ermittlung von Profilen wolkenmikrophysikalischer Eigenschaften. Es können der Extinktionskoeffizient, der effektive Tröpfchenradius, der Flüssigwassergehalt sowie die Tröpfchenanzahlkonzentration bestimmt werden. Weiterhin wird die exakte Erfassung der Wolkenunterkantenhöhe durchdie eingesetzte Messtechnik ermöglicht. Darüber hinaus ist die Bestimmung von Aerosoleigenschaften mit dem eingesetzten Lidargerät möglich. Die Qualität des realisierten Messaufbaus wurde geprüft und eine Fehleranalyse durchgeführt. Unter anderem wurde der aus einer Wolkenmessung bestimmte Flüssigwassergehalt mit einem Mikrowellen-Radiometer bestätigt. Anhand von Fallbeispielen konnte das Potential dieser Messtechnik demonstriert werden. Die Bedeutung von Profilinformationen von Wolkeneigenschaften für die Untersuchung von Aerosol-Wolken-Wechselwirkungen wurde gezeigt. Weiterhin wurde mit Hilfe eines Doppler-Windlidars der Einfluss der Vertikalwindgeschwindigkeit auf Wolkeneigenschaften und damit Aerosol-Wolken-Wechselwirkungen verdeutlicht. Neunundzwanzig Wolkenmessungen wurden für eine statistische Auswertung bezüglich Aerosol-Wolken-Wechselwirkungen genutzt. Dabei konnte erstmalig die Abhängigkeit von Aerosol-Wolken-Wechselwirkungen von der Wolkeneindringtiefe untersucht werden. Es wurde festgestellt, dass diese auf die untersten 70m von Wolken beschränkt sind. Weiterhin wurden deutlich stärkere Aerosol-Wolken-Wechselwirkungen in Wolkengebieten festgestellt, die von Aufwinden dominiert werden. Für der Quantifizierung der Stärke von Aerosol-Wolken-Wechselwirkungen wurden ACIN-Werte genutzt, welche den Zusammenhang zwischen der Tröpfchenanzahlkonzentration und dem Aerosol-Extinktionskoeffizienten beschreiben. Dabei wurde zwischen der Untersuchung der entsprechenden mikrophysikalischen Prozesse und deren Bedeutung für die Wolkenalbedo und damit dem Strahlungsantrieb der Wolken unterschieden. Für die erstgenannte Zielstellung wurde ein ACIN-Wert von 0.80 +/- 0.40 ermittelt, für Letztere 0.13 +/- 0.07.

Nichman, Leonid. "Optical measurements of the microphysical properties of aerosol and small cloud particles in the CLOUD project". Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/optical-measurements-of-the-microphysical-properties-of-aerosol-and-small-cloud-particles-in-the-cloud-project(ad792d0c-90d1-4704-b666-b75d284b40fe).html.

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Clouds play an important role in precipitation, solar radiation budget and electrification of Earth's atmosphere. The presence of small ice crystals in clouds and their morphology can complicate parametrisation and climate modelling, consequently leading to a net cooling feedback on climate. In situ airborne measurements provide single particle characterisation with high temporal and spatial resolution allowing better understanding of atmosphericprocesses of ice nucleation and growth. Simulations of the preindustrial clouds and accurate characterisation and comparison of the instruments require a well-controlled and often pristine environment. The experimental chamber setup allows simulations of these and other conditions. The microphysical features of the micrometric ice particles in clouds were examined in a laboratory setup, at numerous sub-zero temperatures [-10 to -50 ⁰C]. The following instruments were sampling the content of the CLOUD chamber air volume: Cloud and Aerosol Spectrometer with Polarisation (CASPOL), Particle Phase Discriminator mark 2 (PPD-2K, Karlsruhe edition), 3-View Cloud Particle Imager (3V-CPI), and the Scattering-Intensity-Measurements-for-the-Optical-detectioN-of-icE (SIMONE-Junior). Cluster analysis was applied to the data collected with CASPOL and compared with results from the other probes. We were able to discriminate and map the aerosol and cloud particles in the pristine chamber environment using polarisation ratios (Dpol/Backscatter and Dpol/Forwardscatter) of the scattered light. We demonstrate the sensitivity of the instruments in detecting secondary organic aerosol (SOA) phase transitions. Then, we show the ability of the viscous SOA to nucleate ice in a series of SPectrometer for Ice Nuclei (SPIN) measurements. The detected viscous SOA ice nucleation efficiency may affect global modelling and estimations of ice water content in the atmosphere. Subsequently, the analysis and discrimination technique used in the CLOUD chamber was applied to airborne measurements to test its efficiency and to retrieve the composition of clouds. Data from four flight campaigns on board of the FAAM BAe-146 were analysed: Aerosol-Cloud Coupling and Climate Interactions in the Arctic (ACCACIA), COnvective-Precipitation-Experiment (COPE) in south England, CIRrus Coupled Cloud-Radiation EXperiment (CIRCCREX), and PIKNMIX in Scotland. In these and other flights, we were able to identify unique clusters such as salts, minerals, organics, volcanic ash, water and ice, confirming some of the offline laboratory elemental analysis results, and providing complementary information. Single particle polarisation measurements were compared with bulk depolarisation, diffraction patterns, and imaging. Most of the optical instruments still suffer from ambiguity in phase derivation (i.e. water/ice) of optically spherical small shapes. We discuss some of the limitations of optical cloud particle discrimination in different ambient conditions and offer possible solutions to reduce the uncertainty, e.g., surface complexity derivation from scatteringpatterns. Our findings will help to develop better instruments and improve the models which are used for weather forecasts and climate change predictions.

Ditas, Florian. "Microphysical properties of aerosol particles in the trade wind regime and their influence on the number concentration of activated particles in trade wind cumulus clouds". Doctoral thesis, Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-151594.

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Im Rahmen dieser Dissertation wurden die mikrophysikalischen Eigenschaften von Aerosolpartikeln im Passatklima und deren Einfluss auf Passatwolken untersucht. Die Arbeit basiert auf Messungen mit der hubschrauber-getragenen Messplattform ACTOS. Es wurden zwei Intensivmesskampagnen im November 2010 und April 2011 durchgeführt, welche 31 Forschungsflüge in der Nähe der östlichsten Karibik-Insel Barbados umfassen. Die gemessenen Partikel-Anzahl-Größenverteilungen weisen meist eine bimodale Verteilung auf, welche typisch für marines Aerosol ist. Im Vergleich zu kontinentalen Verhältnissen ist die Totalanzahlkonzentration der Aerosolpartikel von 100-1000 cm-3 gering. Eine statistische Analyse einzelner Wolken lässt auf typische Anzahlkonzentrationen von aktivierten Partikeln bis zu 400 cm-3 und minimale Aktivierungsdurchmesser in der Größenordnung von 40 nm bis 180 nm mit entsprechenden maximalen kritischen Übersättigungen zwischen 0.1 und 0.9% schließen. Zusätzlich wurden wesentliche Einflussfaktoren auf die Anzahlkonzentration aktivierter Partikel identifiziert: 1) Vertikalwind an der Wolkenunterkante und 2) Anzahlkonzentration der verfügbaren Aerosolpartikel, die als Wolkenkondensationskeime dienen können. Mit Hilfe von Beobachtungsdaten und einer umfassenden Sensitivitätsstudie unter Verwendung eines Luftpaketmodells mit spektraler Wolkenmikrophysik wurde die Sensitivität der Wolkentropfenkonzentration gegenüber Änderungen in den physikalischen Eigenschaften und der Hygroskopizität von Aerosolpartikeln untersucht. Die beobachteten Ergebnisse in Form von sogenannten \"aerosol-cloud interaction metrics\" (ACI, Maß für den Einfluss von Änderungen einer bestimmten Aerosoleigenschaft auf eine bestimmte Wolkeneigenschaft) zeigen eine sehr hohe Sensitivität der Tropfenanzahlkonzentration gegenüber Änderungen in der Partikelanzahlkonzentration (in der Nähe des physikalisch sinnvollen Maximums von eins). Diese abgeleiteten ACI-Metriken eignen sich als Basis für Abschätzungen des indirekten Strahlungsantriebes auf der Grundlage von Beobachtungen. Zusätzliche Modellrechnungen umfassen die gemessenen Partikeleigenschaften während der gesamten Kampagnen. Die Ergebnisse unterstreichen besonders die Bedeutung der physikalischen Partikeleigenschaften. Die Suszeptibilität der Tropfenanzahlkonzentration gegenüber Änderungen in der Partikelanzahlkonzentration (Wertebereich: 0-1) ist am größten (> 0.9) für den Fall eines stark ausgeprägten Akkumulations-Mode und nimmt ab, je stärker der Aitken-Mode ausgeprägt ist (> 0.6). Im Gegensatz dazu ist die Sensitivität der Tropfenanzahlkonzentration gegenüber Änderungen in der Hygroskopizität der Partikel generell geringer (< 0.4). Die hier präsentierten Ergebnisse stellen eine umfangreiche Charakterisierung der Aerosol- und Wolkeneigenschaften im Passatklima dar und können helfen, die vorhergesagte Sensitivität der Wolkeneigenschaften in Klimamodellen gegenüber Änderungen der Aerosoleigenschaften zu evaluieren und deren Unsicherheiten zu reduzieren
Within the scope of this dissertation, microphysical properties of aerosol particles in the trade wind regime and their influence on microphysical properties of trade wind cumulus clouds have been investigated. The study is based on measurements performed with the helicopter-borne measurement platform ACTOS. Two intensive measurement periods were carried out in November 2010 and April 2011, including 31 research flights close to the easternmost Caribbean island - Barbados. Aerosol particle number size distributions show a bimodal structure, which is typical for marine aerosol particles. The total particle concentrations of approximately 100-1000 cm-3 are compared to continental conditions relatively low. A statistical analysis of individual clouds reveals typical number concentrations of activated particles up to 400 cm-3 and minimum activation diameters between 40 and 180 nm with corresponding critical supersaturations between 0.1 and 1%. Additionally, major factors affecting the number concentration of activated particles are identifed: 1) vertical wind velocity at cloud base and, 2) number concentration of available aerosol particles as potential cloud condensation nuclei. With the help of observational data and a comprehensive sensitivity study using a spectral cloud microphysical parcel model, the sensitivity of the cloud droplet number concentration towards changes in the microphysical aerosol particle properties and their hygroscopicity has been investigated. Observational results in terms of so-called aerosol-cloud interactions metrics (describes a measure of the influence of changes in one specific aerosol property on one specific cloud property) show a very high sensitivity (close to the physical meaningful maximum of unity) of the number concentration of activated particles towards changes in the particle number concentration. These aerosol-cloud interaction metrics can be used as basis for observationally-based radiative forcing estimates. Additional model calculations cover the entire range of the observed aerosol properties during both campaigns. The results underline particularly the importance of the physical aerosol properties. The calculated susceptibility (valuation: 0-1) of the droplet number concentration towards changes in the particle number concentration is highest (> 0.9) for accumulation mode dominated particle number size distributions and decreases for Aitken mode dominated size distributions (> 0.6). In contrast, for the modeled parameter space, the sensitivity towards changes in the particle hygroscopicity is generally below 0.4. The findings presented in this study represent a comprehensive characterization of aerosol and cloud microphysical properties in the trade wind regime. These findings may help to evaluate the predicted sensitivity of cloud microphysical properties by climate models towards changes in particle microphysical properties and reduce the uncertainties in climate sensitivity estimates

Schmidt, Jörg [Verfasser], Andreas [Akademischer Betreuer] Macke, Andreas [Gutachter] Macke e Herman [Gutachter] Russchenberg. "Dual-field-of-view Raman lidar measurements of cloud microphysical properties : Investigation of aerosol-cloud interactions / Jörg Schmidt ; Gutachter: Andreas Macke, Herman Russchenberg ; Betreuer: Andreas Macke". Leipzig : Universitätsbibliothek Leipzig, 2014. http://d-nb.info/123878867X/34.

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Ditas, Florian [Verfasser], Alfred [Gutachter] Wiedensohler e Alfons [Gutachter] Schwarzenböck. "Microphysical properties of aerosol particles in the trade wind regime and their influence on the number concentration of activated particles in trade wind cumulus clouds / Florian Ditas ; Gutachter: Alfred Wiedensohler, Alfons Schwarzenböck". Leipzig : Universitätsbibliothek Leipzig, 2014. http://d-nb.info/1238789293/34.

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Chang, Yuyang. "Développement d'un nouvelle technique de mesure du profil atmosphérique en aérosols à l'aide d'un lidar Raman-dépolarisation-fluorescence". Electronic Thesis or Diss., Université de Lille (2022-....), 2023. https://pepite-depot.univ-lille.fr/ToutIDP/EDSMRE/2023/2023ULILR060.pdf.

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La connaissance de la répartition verticale des propriétés optiques et microphysiques des aérosols est cruciale pour étudier l'évolution et le transport des aérosols, ainsi que leurs impacts sur la santé humaine, l'environnement local et le climat mondial. Dans ce travail nous avons développé un algorithme BOREAL pour restituer les propriétés microphysiques des aérosols à partir de combinaisons de mesures lidar d'extinction, de rétrodiffusion et de dépolarisation spectrales. Basé sur une estimation de vraisemblance maximale, l'algorithme de restitution utilise une approche d'itération non linéaire pour rechercher la meilleure adéquation entre les mesures et les contraintes. Les propriétés microphysiques des aérosols restituées comprennent la distribution de taille des particules, leur concentration volumique, leur rayon efficace, l'indice de réfraction complexe (CRI) et l'albédo de diffusion simple (SSA).Les performances de BOREAL, sa précision et la sensibilité des mesures sont évaluées à l'aide de données simulées. En général, la précision de la restitution est meilleure pour les particules de mode fin que pour les particules de mode grossier. Les simulations démontrent l'importance de l'exploitation de contraintes a priori pour améliorer la précision de la restitution du CRI et du SSA. Outre les particules sphériques, la performance de la restitution des particules non sphériques est également évaluée en intégrant trois modèles de diffusion de particules différents, à savoir les modèles Sphérique, Sphéroïdale et Irrégulier-Hexaédrique (IH), dans BOREAL. Les résultats montrent que l'intégration des mesures de dépolarisation dans l'inversion est essentielle pour mieux contraindre et stabiliser la restitution. De plus, l'approximation des particules non sphériques par des sphères dégrade manifestement la qualité de la restitution. Enfin, BOREAL est utilisé pour restituer les propriétés aérosols au cours d'événements de feux de biomasse, de poussières désertiques et les d'aérosols continentaux pollués détectés depuis la plateforme ATOLL. Les résultats sont analysés et comparés aux restitutions d'AERONET ainsi qu'aux résultats d'études précédentes, ce qui démontrer la robustesse de BOREAL pour l'application de données réelles et la caractérisation d'aérosols.Ce travail contribue aux études menées dans le cadre du Labex CaPPA et d'ACTRIS en quantifiant les propriétés microphysiques des aérosols à partir des observations lidar
Vertical information on aerosol optical and microphysical properties is of significant importance to study aerosol evolution, transport, as well as their impacts on human health, local environment and global climate. This thesis developed an algorithm, the Basic algOrithm for REtrieval of Aerosol with Lidar (BOREAL), for retrieving heigh-resolved aerosol microphysical properties from combinations of extinction, backscattering and depolarization lidar measurements. Based on maximum likelihood estimation, the retrieval algorithm uses a nonlinear iteration approach to search for the best fit to both measurements and constraints. The retrieved aerosol microphysical properties include particle size distribution, volume concentration, effective radius, complex refractive index (CRI) and single scattering albedo (SSA).The performance of BOREAL, retrieval accuracy and measurement sensitivity are assessed through simulated data. In general, retrieval accuracy is higher for fine-mode particles than coarse-mode particles. The simulations demonstrate the importance of exploiting a priori constraint to improve the retrieval accuracy of CRI and SSA. Apart from spherical particles, performance of retrieving non-spherical particles is also evaluated by integrating three different particle scattering models, i.e., the Sphere, Spheroid and Irregular-Hexahedral (IH) models, into BOREAL. The results show incorporating depolarization measurements into inversion is essential to better constrain and stabilize the retrieval. Besides, approximating non-spherical particles to spheres will evidently degrade retrieval quality in cases of lidar measurements. In addition, BOREAL is applied to real lidar observations of different aerosol types, including biomass burning, dust and continental polluted aerosols at the ATOLL observatory. Results are analyzed and compared with retrievals from AERONET and previous studies, which demonstrates the robustness of BOREAL for real data application and aerosol characterization.Overall, this work contributes to Labex CaPPA and ACTRIS efforts to better quantify aerosol microphysical properties using lidar measurements

Ridley, David A. "Aerosol Radiative Properties Analysed using Global Models of Aerosol Microphysics". Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494262.

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Capitoli di libri sul tema "Aerosol microphysical properties":

Obiso, V., M. Pandolfi, M. Ealo e O. Jorba. "Impact of Aerosol Microphysical Properties on Mass Scattering Cross Sections". In Air Pollution Modeling and its Application XXV, 599–604. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-57645-9_93.

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Pugatshova, Anna, Ülle Kikas, Margit Prüssel, Aivo Reinart, Eduard Tamm e Vidmantas Ulevicius. "Relationship of Aerosol Microphysical Properties and Chemical Composition of Aerosol in the Baltic Sea Region". In Nucleation and Atmospheric Aerosols, 711–15. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-6475-3_140.

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Panda, Jagabandhu, e Sunny Kant. "Impact of Urban and Semi-urban Aerosols on the Cloud Microphysical Properties and Precipitation". In Air Pollution and Its Complications, 25–36. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70509-1_3.

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Balis, D., E. Giannakaki, V. Amiridis, R. E. Mamouri, P. Kokkalis, G. Tsaknakis e A. Papayannis. "Forest Fire Aerosols: Vertically Resolved Optical and Microphysical Properties and Mass Concentration from Lidar Observations". In Advances in Meteorology, Climatology and Atmospheric Physics, 905–10. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29172-2_126.

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Rapp, Markus, Irina Strelnikova, Boris Strelnikov, Martin Friedrich, Jörg Gumbel, Ulf-Peter Hoppe, Tom Blix et al. "Microphysical Properties of Mesospheric Aerosols: An Overview of In Situ-Results from the ECOMA Project". In Aeronomy of the Earth's Atmosphere and Ionosphere, 67–74. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-0326-1_4.

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Charlson, R. J. "The Vanishing Climatic Role of Dimethyl Sulfide". In Biotic Feedbacks in the Global Climatic System, 251–62. Oxford University PressNew York, NY, 1995. http://dx.doi.org/10.1093/oso/9780195086409.003.0017.

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Abstract Among the factors that influence the heat balance of the globe, the amount, location, and microphysical properties of aerosol particles and water clouds pose some of the largest uncertainties for forecasting future climate change. Of the key microphysical properties of aerosols, the scattering of shortwave (solar) radiation and the concentration of cloud condensation nuclei (CCN) are of particular interest to chemists because most scattering particles and CCN are produced in the atmosphere through chemical reactions of reactive gases. Of these gases, dimethyl sulfide (OMS) produced by marine phytoplankton is of singular importance because it appears to dominate the natural CCN production over the oceans, which cover about two-thirds of the area of the globe.

DeMott, Paul. "Laboratory Studies of Cirrus Cloud Processes". In Cirrus. Oxford University Press, 2002. http://dx.doi.org/10.1093/oso/9780195130720.003.0009.

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A number of processes that play a role in the formation, evolution of microphysical properties, and radiative characteristics of cirrus clouds are amenable to investigation in a laboratory setting. These laboratory studies provide fundamental data for quantifying and validating theoretical concepts and help guide investigations involving direct and remote measurements of cirrus. Laboratory data also may be used for formulating parameterizations for numerical cloud models, especially where information is incomplete or full descriptions are not possible. This chapter reviews results from laboratory studies of ice formation, ice crystal growth, radiative transfer, and aerosol scavenging and transformation in the cirrus environment. Emphasis is placed on ice formation in cirrus conditions. The related topic of contrail formation is covered separately in this book. The formation mechanisms of lower stratospheric clouds are reviewed elsewhere (e.g., Tolbert 1994; Peter 1996; Carslaw et al. 1997; Koop et al. 1997a). Laboratory studies of cirrus ice formation are at a rapidly developing stage, so it is useful to provide significant background bases for current and needed studies. Key issues are aerosol composition, ice nucleation mechanisms, and the synergy between theory and laboratory measurements. Vali (1996), Baker (1997) and Martin (2000) discuss some of these issues in review papers. Upper tropospheric aerosol particles play an important catalytic role in the formation of cirrus. The nucleation process is important in determining the microphysical properties of cirrus. Numerical modeling studies (e.g., Jensen and Toon 1994; DeMott et al. 1994, 1997; Heymsfield and Sabin 1989) indicate that variation in the factors that drive the nucleation of ice and variations in the physical and chemical characteristics of aerosol particle populations lead to the formation of cirrus with different microphysical characteristics. Knowledge of the physics and chemistry of aerosols in the upper troposphere and lower stratosphere has evolved at a rapid pace. A detailed accounting of this topic is beyond the scope of this chapter. For the purpose of the present discussion, it is sufficient to note that the aerosol from which cirrus nucleate may vary significantly from place to place. Differences in aerosol properties in time and space occur because particles can arrive to the upper troposphere in so many ways and from so many sources.

P. Barros, Ana, Prabhakar Shrestha, Steven Chavez e Yajuan Duan. "Modeling Aerosol-Cloud-Precipitation Interactions in Mountainous Regions: Challenges in the Representation of Indirect Microphysical Effects with Impacts at Subregional Scales". In Rainfall - Extremes, Distribution and Properties. IntechOpen, 2019. http://dx.doi.org/10.5772/intechopen.80025.

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Atti di convegni sul tema "Aerosol microphysical properties":

Ferrare, R. A., S. H. Melfi, D. N. Whiteman e K. D. Evans. "Coincident Measurements of Atmospheric Aerosol Properties and Water Vapor by a Scanning Raman Lidar". In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/orsa.1993.mb.2.

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Knowledge of the physical and optical properties of atmospheric aerosols is required to determine the impact aerosols will have on radiative transfer, heterogeneous chemistry, and cloud dynamics. Since the composition and size of atmospheric aerosols are functions of the atmospheric water vapor, aerosols must be studied in their natural state in order to fully understand how they are affected by various meteorological conditions and how they in turn will affect the processes listed above. By measuring high resolution profiles of aerosol extinction and backscattering as well as simultaneous profiles of atmospheric water vapor, Raman lidar can provide information regarding aerosol microphysical characteristics [Ansmann, et al., 1992; Ferrare et al.,1992]. In addition, the aerosol extinction/backscatter ratio measured directly by Raman lidar can be used in the estimation of aerosol extinction and optical thickness in the inversion procedures used by simpler backscatter lidars. In this presentation, we discuss measurements of aerosol extinction, backscattering, extinction/backscatter ratio, water vapor mixing ratio, and relative humidity made by a scanning Raman lidar over Wallops Island, Virginia (37.95 N, 75.47 W) during August, 1992.

Xu Liu. "Aerosol microphysical properties retrievals from high spectral resolution lidar data". In 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7735285.

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Wandinger, Ulla. "Raman-lidar technique for tropospheric and stratospheric sensing of aerosol optical and microphysical properties". In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1995. http://dx.doi.org/10.1364/orsa.1995.wc1.

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Tropospheric and stratospheric aerosols and clouds are known to influence the earth’s radiation budget as well as chemical processes of the atmosphere. Thus, remote sensing of optical and microphysical properties of atmospheric particles has important applications in weather and climate research, pollution monitoring, and atmospheric chemistry.

Cutten, D. R., E. W. McCaul, J. D. Spinhirne, R. T. Menzies, R. Pueschel, A. D. Clarke e D. A. Bowdle. "Comparison of Remotely Measured Multispectral Scattering Parameters For Tropospheric Aerosols." In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/orsa.1993.the.18.

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In Fall 1989 and Spring 1990 the National Aeronautics and Space Administration (NASA) conducted a number of survey flights on the NASA DC-8 aircraft over the Pacific Basin as part of the GLObal Backscatter Experiment (GLOBE). The main objective of these flights was to collect data on tropospheric aerosol backscatter, either by direct measurement or modeled from measurements of selected aerosol microphysical properties that cover a wide range of spatial and temporal scales. The primary intent of collecting these data is to predict the performance of space-borne lidar systems such as the Laser Atmospheric Wind Sounder (LAWS). Other goals of the GLOBE missions were to characterize the source and properties of aerosols in the middle to upper troposphere over the remote ocean regions.

Gras, John L. "Australian Free Tropospheric Aerosol Measurements". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/clr.1987.wa7.

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Airborne measurements of the spatial and temporal distributions of aerosol particle microphysical properties have been made recently in the Australian region (from the surface to about 6 km altitude). The most recent of these measurement series (a joint CSIRO/NASA field program) along the Australian east coast and across New Guinea, also included simultaneous measurement of particle backscatter at 10 microns and visible wavelength backscatter using ground-based lidar (at two sites). These data are of particular relevance for feasibility studies of satellite IR laser wind determination systems.

Shao, Jiangfeng, e Jiandong Mao. "The observations of aerosol optical and microphysical properties by using a multi-wavelength lidar". In Applied Optics and Photonics China (AOPC2015), a cura di Haimei Gong, Nanjian Wu, Yang Ni, Weibiao Chen e Jin Lu. SPIE, 2015. http://dx.doi.org/10.1117/12.2199489.

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Ansmann, A., D. Müller, U. Wandinger e R. E. Mamouri. "Lidar profiling of aerosol optical and microphysical properties from space: overview, review, and outlook". In First International Conference on Remote Sensing and Geoinformation of Environment, a cura di Diofantos G. Hadjimitsis, Kyriacos Themistocleous, Silas Michaelides e George Papadavid. SPIE, 2013. http://dx.doi.org/10.1117/12.2028112.

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Bockmann, C., L. Osterloh, P. Pornsawad, D. Muller e A. Papayannis. "From EARLINET-ASOS Raman-Lidar Signals to Microphysical Aerosol Properties Via Advanced Regularizing Software". In IGARSS 2008 - 2008 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2008. http://dx.doi.org/10.1109/igarss.2008.4779018.

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Zhamsueva, Galina, Alexander Zayakhanov, Vadim Tsydypov, Tumen Balzhanov, Ayuna Dementeva, Alexey Starikov, Sergey Naguslaev, Yuriy Balin, Dolgorsuren Azzaya e Dugerjav Oyunchimeg. "Chemical composition, microphysical and optical properties of aerosol in the atmosphere of the arid territories of Mongolia". In XXIV International Symposium, Atmospheric and Ocean Optics, Atmospheric Physics, a cura di Oleg A. Romanovskii e Gennadii G. Matvienko. SPIE, 2018. http://dx.doi.org/10.1117/12.2502030.

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Ajtai, Nicolae. "CHARACTERIZATION OF AEROSOL OPTICAL AND MICROPHYSICAL PROPERTIES OVER NORTH-WESTERN ROMANIA IN CORRELATION WITH PREDOMINANT ATMOSPHERIC CIRCULATION PATTERNS". In 17th International Multidisciplinary Scientific GeoConference SGEM2017. Stef92 Technology, 2017. http://dx.doi.org/10.5593/sgem2017/41/s19.048.

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Rapporti di organizzazioni sul tema "Aerosol microphysical properties":

Jerry, Harrington, e Nathan Magee. Final Report: Characterizing the Small-Scale Dynamical, Ice Microphysical, and Residual Aerosol Properties of Mid-Latitude Cold Clouds: A Pilot Study. Office of Scientific and Technical Information (OSTI), dicembre 2023. http://dx.doi.org/10.2172/2248071.

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Hostetler, Chris, e Richard Ferrare. Final Technical Report for Interagency Agreement No. DE-SC0005453 “Characterizing Aerosol Distributions, Types, and Optical and Microphysical Properties using the NASA Airborne High Spectral Resolution Lidar (HSRL) and the Research Scanning Polarimeter (RSP)”. Office of Scientific and Technical Information (OSTI), gennaio 2015. http://dx.doi.org/10.2172/1167162.

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