Tropospheric and stratospheric wildfire smoke profiling with lidar: Mass, surface area, CCN and INP retrieval

Abstract. We present retrievals of tropospheric and stratospheric height profiles of particle mass, volume, and surface area concentrations in the case of wildfire smoke layers as well as estimates of smoke-related cloud condensation nucleus (CCN) and ice-nucleating particle (INP) concentrations from single-wavelength backscatter lidar measurements at ground and in space. A central role in the data analysis play conversion factors to convert the measured optical into microphysical properties. The set of needed conversion parameters for wildfire smoke are derived from AERONET observations of major smoke events caused by record-breaking wildfires in western Canada in August 2017 and southeastern Australia in January–February 2020. The new smoke analysis scheme is applied to stratospheric CALIPSO observations of fresh smoke plumes over northern Canada in 2017 and New Zealand in January 2020 and to ground-based lidar observation in southern Chile in aged Australian smoke layers in January 2020. These case studies show the potential of spaceborne and ground-based lidars to document large-scale and long-lasting wildfire smoke events in large detail and thus to provide valuable information for climate-, cloud-, and air chemistry modeling efforts performed to investigate the role of wildfire smoke in the atmospheric system.

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Tropospheric and stratospheric wildfire smoke profiling with lidar: mass, surface area, CCN, and INP retrieval

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-9779-2021 ◽

2021 ◽

Vol 21 (12) ◽

pp. 9779-9807

Author(s):

Albert Ansmann ◽

Kevin Ohneiser ◽

Rodanthi-Elisavet Mamouri ◽

Daniel A. Knopf ◽

Igor Veselovskii ◽

...

Keyword(s):

Surface Area ◽

Large Scale ◽

Cloud Condensation Nuclei ◽

The United States ◽

Optical Measurements ◽

Wildfire Smoke ◽

Microphysical Properties ◽

Southeastern Australia ◽

Analysis Scheme ◽

Ground Based Lidar

Abstract. We present retrievals of tropospheric and stratospheric height profiles of particle mass, volume, surface area, and number concentrations in the case of wildfire smoke layers as well as estimates of smoke-related cloud condensation nuclei (CCN) and ice-nucleating particle (INP) concentrations from backscatter lidar measurements on the ground and in space. Conversion factors used to convert the optical measurements into microphysical properties play a central role in the data analysis, in addition to estimates of the smoke extinction-to-backscatter ratios required to obtain smoke extinction coefficients. The set of needed conversion parameters for wildfire smoke is derived from AERONET observations of major smoke events, e.g., in western Canada in August 2017, California in September 2020, and southeastern Australia in January–February 2020 as well as from AERONET long-term observations of smoke in the Amazon region, southern Africa, and Southeast Asia. The new smoke analysis scheme is applied to CALIPSO observations of tropospheric smoke plumes over the United States in September 2020 and to ground-based lidar observation in Punta Arenas, in southern Chile, in aged Australian smoke layers in the stratosphere in January 2020. These case studies show the potential of spaceborne and ground-based lidars to document large-scale and long-lasting wildfire smoke events in detail and thus to provide valuable information for climate, cloud, and air chemistry modeling efforts performed to investigate the role of wildfire smoke in the atmospheric system.

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Dust mass, cloud condensation nuclei, and ice-nucleating particle profiling with polarization lidar: updated POLIPHON conversion factors from global AERONET analysis

Atmospheric Measurement Techniques ◽

10.5194/amt-12-4849-2019 ◽

2019 ◽

Vol 12 (9) ◽

pp. 4849-4865 ◽

Cited By ~ 12

Author(s):

Albert Ansmann ◽

Rodanthi-Elisavet Mamouri ◽

Julian Hofer ◽

Holger Baars ◽

Dietrich Althausen ◽

...

Keyword(s):

Surface Area ◽

Cloud Condensation Nuclei ◽

Condensation Nucleus ◽

Cloud Condensation Nucleus ◽

Conversion Factors ◽

Microphysical Properties ◽

Central Asian ◽

Volume Forms ◽

Aerosol Type

Abstract. The POLIPHON (Polarization Lidar Photometer Networking) method permits the retrieval of particle number, surface area, and volume concentration for dust and non-dust aerosol components. The obtained microphysical properties are used to estimate height profiles of particle mass, cloud condensation nucleus (CCN) and ice-nucleating particle (INP) concentrations. The conversion of aerosol-type-dependent particle extinction coefficients, derived from polarization lidar observations, into the aerosol microphysical properties (number, surface area, volume) forms the central part of the POLIPHON computations. The conversion parameters are determined from Aerosol Robotic Network (AERONET) aerosol climatologies of optical and microphysical properties. In this article, we focus on the dust-related POLIPHON retrieval products and present an extended set of dust conversion factors considering all relevant deserts around the globe. We apply the new conversion factor set to a dust measurement with polarization lidar in Dushanbe, Tajikistan, in central Asia. Strong aerosol layering was observed with mineral dust advected from Kazakhstan (0–2 km height), Iran (2–5 km), the Arabian peninsula (5–7 km), and the Sahara (8–10 km). POLIPHON results obtained with different sets of conversion parameters were contrasted in this central Asian case study and permitted an estimation of the conversion uncertainties.

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Dust mass, CCN, and INP profiling with polarization lidar: Updated POLIPHON conversion factors from global AERONET analysis

10.5194/amt-2019-98 ◽

2019 ◽

Author(s):

Albert Ansmann ◽

Rodanthi-Elisavet Mamouri ◽

Julian Hofer ◽

Holger Baars ◽

Dietrich Althausen ◽

...

Keyword(s):

Surface Area ◽

Particle Number ◽

Condensation Nucleus ◽

Ice Nucleation ◽

Cloud Condensation Nucleus ◽

Conversion Factors ◽

Microphysical Properties ◽

Factor Set ◽

Dust Measurement ◽

Area And Volume

Abstract. The POLIPHON (Polarization Lidar Photometer Networking) method permits the retrieval of particle number, surface area, and volume concentration for dust and non-dust aerosol components. The obtained microphysical properties are used to estimate height profiles of particle mass, cloud condensation nucleus (CCN) and ice-nucleation particle (INP) concentrations. Of central importance is the conversion of the lidar-derived extinction profiles into aerosol miccrophysical properties (number, surface area, volume). These conversion parameters are determined from Aerosol Robotic Network (AERONET) aerosol climatologies of optical and microphysical properties. In this article we focus on the dust-related POLIPHON retrieval and present an updated set of dust conversion factors considering all relevant deserts around the globe. We apply the new conversion factor set to a dust measurement with polarization lidar in Dushanbe, Tajikistan, in central Asia. Strong aerosol layering was observed with mineral dust advected from Kazakhstan (0–2 km height), Iran (2–5 km), the Arabian peninsula (5–7 km), and the Sahara (8–10 km). POLIPHON results obtained with different sets of conversion parameters were contrasted and discussed in terms of uncertainties.

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No statistically significant effect of a short-term decrease in the nucleation rate on atmospheric aerosols

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-15373-2012 ◽

2012 ◽

Vol 12 (6) ◽

pp. 15373-15417 ◽

Cited By ~ 1

Author(s):

E. M. Dunne ◽

L. A. Lee ◽

C. L. Reddington ◽

K. S. Carslaw

Keyword(s):

Nucleation Rate ◽

Atmospheric Aerosols ◽

Large Scale ◽

Cloud Condensation Nuclei ◽

Cosmic Ray ◽

Condensation Nucleus ◽

Cloud Condensation Nucleus ◽

Significant Response ◽

Short Term ◽

Aerosol Properties

Abstract. Observed correlations between short-term decreases in cosmic ray ionisation and cloud and aerosol properties have been attributed to short-term decreases in the ion-induced nucleation rate. We use a global aerosol microphysics model to determine whether a 10-day reduction of 15% in the nucleation rate could generate a statistically significant response in aerosol concentrations and optical properties. As an upper limit to the possible effect of changes in the ion-induced nucleation rate, we perturb the total nucleation rate, which has been shown to generate particle concentrations and nucleation events in reasonable agreement with global observations. When measured against a known aerosol control state, the model predicts a 0.15% decrease in global mean cloud condensation nucleus concentrations at the surface. However, taking into account the variability in aerosol, no statistically significant response can be detected in concentrations of particles with diameters larger than 10 nm, in cloud condensation nuclei with diameters larger than 70 nm, or in the Ångström exponent. The results suggest that the observed correlation between short-term decreases in cosmic ray ionisation and cloud and aerosol properties cannot be explained by associated changes in the large-scale nucleation rate.

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The dual-field-of-view polarization lidar technique: a new concept in monitoring aerosol effects in liquid-water clouds – theoretical framework

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-15247-2020 ◽

2020 ◽

Vol 20 (23) ◽

pp. 15247-15263 ◽

Cited By ~ 1

Author(s):

Cristofer Jimenez ◽

Albert Ansmann ◽

Ronny Engelmann ◽

David Donovan ◽

Aleksey Malinka ◽

...

Keyword(s):

Extinction Coefficient ◽

Liquid Water ◽

Cloud Droplet ◽

Condensation Nucleus ◽

Liquid Water Content ◽

Theoretical Background ◽

Effective Radius ◽

Cloud Condensation Nucleus ◽

Cloud Base ◽

Analysis Scheme

Abstract. In a series of two articles, a novel, robust, and practicable lidar approach is presented that allows us to derive microphysical properties of liquid-water clouds (cloud extinction coefficient, droplet effective radius, liquid-water content, cloud droplet number concentration) at a height of 50–100 m above the cloud base. The temporal resolution of the observations is on the order of 30–120 s. Together with the aerosol information (aerosol extinction coefficients, cloud condensation nucleus concentration) below the cloud layer, obtained with the same lidar, in-depth aerosol–cloud interaction studies can be performed. The theoretical background and the methodology of the new cloud lidar technique is outlined in this article (Part 1), and measurement applications are presented in a companion publication (Part 2) (Jimenez et al., 2020a). The novel cloud retrieval technique is based on lidar observations of the volume linear depolarization ratio at two different receiver fields of view (FOVs). Extensive simulations of lidar returns in the multiple scattering regime were conducted to investigate the capabilities of a dual-FOV polarization lidar to measure cloud properties and to quantify the information content in the measured depolarization features regarding the basic retrieval parameters (cloud extinction coefficient, droplet effective radius). Key simulation results and the overall data analysis scheme developed to obtain the aerosol and cloud products are presented.

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No statistically significant effect of a short-term decrease in the nucleation rate on atmospheric aerosols

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-11573-2012 ◽

2012 ◽

Vol 12 (23) ◽

pp. 11573-11587 ◽

Cited By ~ 15

Author(s):

E. M. Dunne ◽

L. A. Lee ◽

C. L. Reddington ◽

K. S. Carslaw

Keyword(s):

Nucleation Rate ◽

Atmospheric Aerosols ◽

Large Scale ◽

Cloud Condensation Nuclei ◽

Cosmic Ray ◽

Condensation Nucleus ◽

Cloud Condensation Nucleus ◽

Significant Response ◽

Short Term ◽

Aerosol Properties

Abstract. Observed correlations between short-term decreases in cosmic ray ionisation and cloud and aerosol properties have been attributed to short-term decreases in the ion-induced nucleation rate. We use a global aerosol microphysics model to determine whether a 10 day reduction of 15% in the nucleation rate could generate a statistically significant response in aerosol concentrations and optical properties. As an upper limit to the possible effect of changes in ion-induced nucleation rate, we perturb the total nucleation rate, which has been shown to generate particle concentrations and nucleation events in reasonable agreement with global observations. When measured against a known aerosol control state, the model predicts a 0.15% decrease in global mean cloud condensation nucleus concentration at the surface. However, taking into account the variability in aerosol, no statistically significant response can be detected in concentrations of particles with diameters larger than 10 nm, in cloud condensation nuclei with diameters larger than 70 nm, or in the Ångström exponent. The results suggest that the observed correlation between short-term decreases in cosmic ray ionisation and cloud and aerosol properties cannot be explained by associated changes in the large-scale nucleation rate.

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Fluorescence lidar observations of wildfire smoke inside cirrus: A contribution to smoke-cirrus – interaction research

10.5194/acp-2021-1017 ◽

2021 ◽

Author(s):

Igor Veselovskii ◽

Qiaoyun Hu ◽

Albert Ansmann ◽

Philippe Goloub ◽

Thierry Podvin ◽

...

Keyword(s):

Surface Area ◽

Ice Crystal ◽

Raman Lidar ◽

Upper Troposphere ◽

Wildfire Smoke ◽

Microphysical Properties ◽

Lidar Measurements ◽

Lidar Observations ◽

Interaction Research ◽

Area And Volume

Abstract. A remote sensing method, based on fluorescence lidar measurements, that allows to detect and to quantify the smoke content in upper troposphere and lower stratosphere (UTLS) is presented. The unique point of this approach is that, smoke and cirrus properties are observed in the same air volume simultaneously. In the article, we provide results of fluorescence and multiwavelength Mie-Raman lidar measurements performed at ATOLL observatory from Laboratoire d’Optique Atmosphérique, University of Lille, during strong smoke episodes in the summer and autumn seasons of 2020. The aerosol fluorescence was induced by 355 nm laser radiation and the fluorescence backscattering was measured in a single spectral channel, centered at 466 nm of 44 nm width. To estimate smoke properties, such as number, surface area and volume concentration, the conversion factors, which link the fluorescence backscattering and the smoke microphysical properties, are derived from the synergy of multiwavelength Mie-Raman and fluorescence lidar observations. Based on two case studies, we demonstrate that the fluorescence lidar technique provides possibility to estimate the smoke surface area concentration within freshly formed cirrus layers. This value was used in smoke INP parameterization scheme to predict ice crystal number concentrations in cirrus generation cells.

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The dual-field-of-view polarization lidar technique: A new concept in monitoring aerosol effects in liquid-water clouds – Theoretical framework

10.5194/acp-2020-473 ◽

2020 ◽

Author(s):

Cristofer Jimenez ◽

Albert Ansmann ◽

Ronny Engelmann ◽

David Donovan ◽

Aleksey Malinka ◽

...

Keyword(s):

Extinction Coefficient ◽

Liquid Water ◽

Cloud Droplet ◽

Condensation Nucleus ◽

Liquid Water Content ◽

Theoretical Background ◽

Effective Radius ◽

Cloud Condensation Nucleus ◽

Cloud Base ◽

Analysis Scheme

Abstract. In a series of two articles, a novel, robust, and practicable lidar approach is presented that allows us to derive microphysical properties of liquid-water clouds (cloud extinction coefficient, droplet effective radius, liquid-water content, cloud droplet number concentration) at a height of 50–100 m above cloud base. The temporal resolution of the observations is on the order of 30–120 sec. Together with the aerosol information (aerosol extinction coefficients, cloud condensation nucleus concentration) below the cloud layer, obtained with the same lidar, in-depth aerosol-cloud interaction studies can be performed. The theoretical background and the methodology of the new cloud lidar technique is outlined in this article (part 1), measurement applications are presented in an companion publication (part 2). The novel cloud retrieval technique is based on lidar observations of the volume linear depolarization ratio at two different receiver field-of-views (FOVs). Extensive simulations of lidar returns in the multiple scattering regime were conducted to investigate the capabilities of a dual-FOV polarization lidar to measure cloud properties and to quantify the information content in the measured depolarization features regarding the basic retrieval parameters (cloud extinction coefficient, droplet effective radius). Key simulation results and the developed overall data analysis scheme to obtain the aerosol and cloud products are presented.

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