scholarly journals Biomass burning aerosol heating rates from the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) 2016 and 2017 experiments

2022 ◽  
Vol 15 (1) ◽  
pp. 61-77
Author(s):  
Sabrina P. Cochrane ◽  
K. Sebastian Schmidt ◽  
Hong Chen ◽  
Peter Pilewskie ◽  
Scott Kittelman ◽  
...  
Keyword(s):  
Heating Rate ◽  
Biomass Burning ◽  
Atmospheric Stability ◽  
Single Scattering ◽  
Aerosol Layer ◽  
Aerosol Extinction ◽  
Heating Rates ◽  
Water Vapor Absorption ◽  
Cloud Properties ◽  
Southeastern Atlantic

Abstract. Aerosol heating due to shortwave absorption has implications for local atmospheric stability and regional dynamics. The derivation of heating rate profiles from space-based observations is challenging because it requires the vertical profile of relevant properties such as the aerosol extinction coefficient and single-scattering albedo (SSA). In the southeastern Atlantic, this challenge is amplified by the presence of stratocumulus clouds below the biomass burning plume advected from Africa, since the cloud properties affect the magnitude of the aerosol heating aloft, which may in turn lead to changes in the cloud properties and life cycle. The combination of spaceborne lidar data with passive imagers shows promise for future derivations of heating rate profiles and curtains, but new algorithms require careful testing with data from aircraft experiments where measurements of radiation, aerosol, and cloud parameters are better colocated and readily available. In this study, we derive heating rate profiles and vertical cross sections (curtains) from aircraft measurements during the NASA ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) project in the southeastern Atlantic. Spectrally resolved irradiance measurements and the derived column absorption allow for the separation of total heating rates into aerosol and gas (primarily water vapor) absorption. The nine cases we analyzed capture some of the co-variability of heating rate profiles and their primary drivers, leading to the development of a new concept: the heating rate efficiency (HRE; the heating rate per unit aerosol extinction). HRE, which accounts for the overall aerosol loading as well as vertical distribution of the aerosol layer, varies little with altitude as opposed to the standard heating rate. The large case-to-case variability for ORACLES is significantly reduced after converting from heating rate to HRE, allowing us to quantify its dependence on SSA, cloud albedo, and solar zenith angle.

scholarly journals Biomass Burning Aerosol Heating Rates from the ORACLES 2016 and 2017 Experiments

2021 ◽  
Author(s):  
Sabrina P. Cochrane ◽  
K. Sebastian Schmidt ◽  
Hong Chen ◽  
Peter Pilewskie ◽  
Scott Kittleman ◽  
...  
Keyword(s):  
Heating Rate ◽  
Biomass Burning ◽  
Atmospheric Stability ◽  
Single Scattering ◽  
Aerosol Layer ◽  
Aerosol Extinction ◽  
Heating Rates ◽  
Water Vapor Absorption ◽  
Cloud Parameters ◽  
Cloud Properties

Abstract. Aerosol heating due to shortwave absorption has implications for local atmospheric stability and regional dynamics. The derivation of heating rate profiles from space-based observations is challenging because it requires the vertical profile of relevant properties such as the aerosol extinction coefficient and single scattering albedo (SSA). In the southeast Atlantic, this challenge is amplified by the presence of stratocumulus clouds below the biomass burning plume advected from Africa, since the cloud properties affect the magnitude of the aerosol heating aloft, which may in turn lead to changes in the cloud properties and life cycle. The combination of spaceborne lidar data with passive imagers shows promise for future derivations of heating rate profiles and curtains, but new algorithms require careful testing with data from aircraft experiments where measurements of radiation, aerosol and cloud parameters are better collocated and readily available. In this study, we derive heating rate profiles and curtains from aircraft measurements during the NASA ObseRvations of CLouds above Aerosols and their intEractionS (ORACLES) project in the southeastern Atlantic. Spectrally resolved irradiance measurements and the derived column absorption allow for the separation of total heating rates into aerosol and gas (primarily water vapor) absorption. The nine cases we analyzed capture some of the co-variability of heating rate profiles and their primary drivers, leading to the development of a new concept: The Heating Rate Efficiency (HRE; the heating rate per unit aerosol extinction). The HRE, which accounts for the overall aerosol loading as well as vertical distribution of the aerosol layer, varies little with altitude as opposed to the standard heating rate. The large case-to-case variability for ORACLES is significantly reduced after converting from heating rate to HRE, allowing us to quantify its dependence on SSA, cloud albedo, and solar zenith angle.

scholarly journals Physical properties and concentration of aerosol particles over the Amazon tropical forest during background and biomass burning conditions

2003 ◽  
Vol 3 (4) ◽  
pp. 951-967 ◽  
Author(s):  
P. Guyon ◽  
B. Graham ◽  
J. Beck ◽  
O. Boucher ◽  
E. Gerasopoulos ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Large Scale ◽  
Marine Boundary Layer ◽  
Global Climate ◽  
Single Scattering ◽  
Dry Season ◽  
Aerosol Layer ◽  
Wet Season ◽  
Cloud Properties ◽  
Tenfold Increase

Abstract. We investigated the size distribution, scattering and absorption properties of Amazonian aerosols and the optical thickness of the aerosol layer under the pristine background conditions typical of the wet season, as well as during the biomass-burning-influenced dry season. The measurements were made during two campaigns in 1999 as part of the European contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA-EUSTACH). In moving from the wet to the dry season, median particle numbers were observed to increase from values comparable to those of the remote marine boundary layer (~400 cm-3) to values more commonly associated with urban smog (~4000 cm-3), due to a massive injection of submicron smoke particles. Aerosol optical depths at 500 nm increased from 0.05 to 0.8 on average, reaching a value of 2 during the dry season. Scattering and absorption coefficients, measured at 550 nm, showed a concomitant increase from average values of 6.8 and 0.4 Mm-1 to values of 91 and 10 Mm-1, respectively, corresponding to an estimated decrease in single-scattering albedo from ca. 0.97 to 0.91. The roughly tenfold increase in many of the measured parameters attests to the dramatic effect that extensive seasonal biomass burning (deforestation, pasture cleaning) is having on the composition and properties of aerosols over Amazonia. The potential exists for these changes to impact on regional and global climate through changes to the extinction of solar radiation as well as the alteration of cloud properties.

scholarly journals Physical properties and concentration of aerosol particles over the Amazon tropical forest during background and biomass burning conditions

2003 ◽  
Vol 3 (2) ◽  
pp. 1367-1414 ◽  
Author(s):  
P. Guyon ◽  
B. Graham ◽  
J. Beck ◽  
O. Boucher ◽  
E. Gerasopoulos ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Large Scale ◽  
Marine Boundary Layer ◽  
Global Climate ◽  
Single Scattering ◽  
Dry Season ◽  
Aerosol Layer ◽  
Wet Season ◽  
Cloud Properties ◽  
Tenfold Increase

Abstract. We investigated the size distribution, scattering and absorption properties of Amazonian aerosols and the optical thickness of the aerosol layer under the pristine background conditions typical of the wet season, as well as during the biomass-burning-influenced dry season. The measurements were made during two campaigns in 1999 as part of the European contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA-EUSTACH). In moving from the wet to the dry season, median particle numbers were observed to increase from values comparable to those of the remote marine boundary layer (~400cm−3) to values more commonly associated with urban smog (~4000 cm−3), due to a massive injection of submicron smoke particles. Aerosol optical depths at 500\\,nm increased from 0.05 to 0.8 on average, reaching a value of 2 during the dry season. Scattering and absorption coefficients, measured at 550 nm, showed a concomitant increase from average values of 6.8 and 0.4 Mm−1 to values of 91 and 10 Mm−1, respectively, corresponding to an estimated decrease in single-scattering albedo from ca. 0.97 to 0.91. The roughly tenfold increase in many of the measured parameters attests to the dramatic effect that extensive seasonal biomass burning (deforestation, pasture cleaning) is having on the composition and properties of aerosols over Amazonia. The potential exists for these changes to impact on regional and global climate through changes to the extinction of solar radiation as well as the alteration of cloud properties.

scholarly journals Radiative Heating Rate Profiles over the Southeast Atlantic Ocean during the 2016 and 2017 Biomass Burning Seasons

2020 ◽  
Author(s):  
Allison B. Marquardt Collow ◽  
Mark A. Miller ◽  
Lynne C. Trabachino ◽  
Michael P. Jensen ◽  
Meng Wang
Keyword(s):  
Atlantic Ocean ◽  
Heating Rate ◽  
Biomass Burning ◽  
Radiative Heating ◽  
Aerosol Layer ◽  
Field Campaign ◽  
Cloud Structure ◽  
Ascension Island ◽  
Biomass Burning Aerosol ◽  
Aerosol Plume

Abstract. Marine boundary layer clouds, including the transition from stratocumulus to cumulus, are poorly represented in numerical weather prediction and general circulation models. Further uncertainties in the cloud structure arise in the presence of biomass burning carbonaceous aerosol, as is the case over the southeast Atlantic Ocean where biomass burning aerosol is transported from the African continent. As the aerosol plume progresses across the southeast Atlantic Ocean, radiative heating within the aerosol layer has the potential to alter the thermodynamic environment and therefore the cloud structure; however, this has yet to be quantified. The deployment of the First Atmospheric Radiation Measurement Mobile Facility (AMF1) in support of the Layered Atlantic Smoke Interactions with Clouds (LASIC) field campaign provided a unique opportunity to collect observations of cloud and aerosol properties during two consecutive biomass burning seasons during July through October of 2016 and 2017 over Ascension Island (7.96 S, 14.35 W). Using observed profiles of temperature, humidity, and clouds from the LASIC field campaign, alongside aerosol optical properties from the Modern Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) as input for the Rapid Radiation Transfer Model (RRTM), profiles of the radiative heating rate due to aerosols and clouds were computed. Radiative heating is also assessed across the southeast Atlantic Ocean using an ensemble of back trajectories from the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT). Idealized experiments using RRTM with and without aerosols and a range of values for the single scattering albedo demonstrate that shortwave (SW) heating within the aerosol layer above Ascension Island can locally range between 2 and 8 K per day, though impacts of the aerosol can be felt elsewhere in the atmospheric column. SW radiative heating due to biomass burning aerosol is not balanced by additional longwave cooling, and the net radiative impact results in a stabilization of the lower troposphere. However, these results are extremely sensitive to the single scatter albedo and the height of the aerosol plume with respect to the inversion layer.

scholarly journals Aerosol above-cloud direct radiative effect and properties in the Namibian region during the AErosol, RadiatiOn, and CLOuds in southern Africa (AEROCLO-sA) field campaign – Multi-Viewing, Multi-Channel, Multi-Polarization (3MI) airborne simulator and sun photometer measurements

2021 ◽  
Vol 21 (10) ◽  
pp. 8233-8253
Author(s):  
Aurélien Chauvigné ◽  
Fabien Waquet ◽  
Frédérique Auriol ◽  
Luc Blarel ◽  
Cyril Delegove ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Southern Africa ◽  
Single Scattering ◽  
Visible Range ◽  
Radiative Effect ◽  
Field Campaign ◽  
Airborne Measurements ◽  
Cloud Properties ◽  
Fine Mode ◽  
Sun Photometer

Abstract. We analyse the airborne measurements of above-cloud aerosols from the AErosol, RadiatiOn, and CLOuds in southern Africa (AEROCLO-sA) field campaign performed in Namibia during August and September 2017. The study aims to retrieve the aerosol above-cloud direct radiative effect (DRE) with well-defined uncertainties. To improve the retrieval of the aerosol and cloud properties, the airborne demonstrator of the Multi-Viewing, Multi-Channel, Multi-Polarization (3MI) satellite instrument, called the Observing System Including PolaRisation in the Solar Infrared Spectrum (OSIRIS), was deployed on-board the SAFIRE (Service des Avions Français Instrumentés pour la Rechercheen Environnement) Falcon 20 aircraft during 10 flights performed over land, over the ocean, and along the Namibian coast. The airborne instrument OSIRIS provides observations at high temporal and spatial resolutions for aerosol above clouds (AACs) and cloud properties. OSIRIS was supplemented with the Photomètre Léger Aéroporté pour la surveillance des Masses d'Air version 2 (PLASMA2). The combined airborne measurements allow, for the first time, the validation of AAC algorithms previously developed for satellite measurements. The variations in the aerosol properties are consistent with the different atmospheric circulation regimes observed during the deployment. Airborne observations typically show strong aerosol optical depth (AOD; up to 1.2 at 550 nm) of fine-mode particles from biomass burning (extinction Ångström exponent varying between 1.6 and 2.2), transported above bright stratocumulus decks (mean cloud top around 1 km above mean sea level), with cloud optical thickness (COT) up to 35 at 550 nm. The above-cloud visible AOD retrieved with OSIRIS agrees within 10 % of the PLASMA2 sun photometer measurements in the same environment. The single scattering albedo (SSA) is one of the most influential parameters on the AAC DRE calculation that remains largely uncertain in models. During the AEROCLO-sA campaign, the average SSA obtained by OSIRIS at 550 nm is 0.87, which is in agreement within 3 %, on average, with previous polarimetric-based satellite and airborne retrievals. The strong absorption of the biomass burning plumes in the visible range is generally consistent with the observations from the Aerosol Robotic Network (AERONET) ground-based sun photometers. This, however, shows a significant increase in the particles' absorption at 440 nm in northern Namibia and Angola, which indicates more absorbing organic species within the observed smoke plumes. Biomass burning aerosols are also vertically collocated, with significant amounts of water content up to the top of the plume at around 6 km height in our measurements. The detailed characterization of aerosol and cloud properties, water vapour, and their uncertainties obtained from OSIRIS and PLASMA2 measurements allows us to study their impacts on the AAC DRE. The high-absorbing load of AAC, combined with high cloud albedo, leads to unprecedented DRE estimates, which are higher than previous satellite-based estimates. The average AAC DRE calculated from the airborne measurements in the visible range is +85 W m−2 (standard deviation of 26 W m−2), with instantaneous values up to +190 W m−2 during intense events. These high DRE values, associated with their uncertainties, have to be considered as new upper cases in order to evaluate the ability of models to reproduce the radiative impact of the aerosols over the southeastern Atlantic region.

scholarly journals Vertical structure of biomass burning aerosol transported over the southeast Atlantic Ocean

2021 ◽  
Author(s):  
Harshvardhan Harshvardhan ◽  
Richard Ferrare ◽  
Sharon Burton ◽  
Johnathan Hair ◽  
Chris Hostetler ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Biomass Burning ◽  
Radiative Forcing ◽  
High Spectral Resolution ◽  
Aerosol Layer ◽  
Aerosol Extinction ◽  
Microphysical Properties ◽  
Stratocumulus Clouds ◽  
Fine Mode ◽  
Cloud Tops

Abstract. Biomass burning in southwestern Africa produces smoke plumes that are transported over the Atlantic Ocean and overlie vast regions of stratocumulus clouds. This aerosol layer contributes to direct and indirect radiative forcing of the atmosphere in this region, particularly during the months of August, September and October. There was a multi-year international campaign to study this aerosol and its interactions with clouds. Here we report on the evolution of aerosol distributions and properties as measured by the airborne high spectral resolution lidar (HSRL) during the ORACLES (Observations of Aerosols above Clouds and their intEractionS) campaign in September 2016. The NASA Langley HSRL-2 instrument was flown on the NASA ER-2 aircraft for several days in September 2016. Data were aggregated at two pairs of 2° × 2° grid boxes to examine the evolution of the vertical profile of aerosol properties during transport over the ocean. Results showed that the structure of the profile of aerosol extinction and microphysical properties is maintained over a one to two-day time scale. The fraction of aerosol in the fine mode between 50 and 500 nm remained above 0.95 and the effective radius of this fine mode was 0.16 μm from 3 to 5 km in altitude. This indicates that there is essentially no scavenging or dry deposition at these altitudes. Moreover, there is very little day to day variation in these properties, such that time sampling as happens in such campaigns, may be representative of longer periods such as monthly means. Below 3 km there is considerable mixing with larger aerosol, most likely continental source near land. Furthermore, these measurements indicated that there was a distinct gap between the bottom of the aerosol layer and cloud tops at the selected locations as evidenced by a layer of several hundred meters that contained relatively low aerosol extinction values above the clouds.

NASA’s TropOMI Aerosol Products: Algorithm and Preliminary Evaluation Results

2020 ◽  
Author(s):  
Changwoo Ahn ◽  
Omar Torres ◽  
Glen Jaross ◽  
Hiren Jethva ◽  
Xiaoguang Xu ◽  
...  
Keyword(s):  
Optical Depth ◽  
Single Scattering ◽  
Preliminary Evaluation ◽  
Aerosol Layer ◽  
Aerosol Extinction ◽  
Radiometric Calibration ◽  
Algorithmic Approaches ◽  
Cloud Mask ◽  
Aerosol Index ◽  
Aerosol Type

<p>The extended hyperspectral capability with improved spatial resolution of the S5-P/TROPOMI instrument makes it more useful than OMI for observing not only trace gases but also aerosols. We have developed a research algorithm (TROPOMAER) for retrieving aerosol properties from S5-P/TROPOMI L1-b (Version 01) radiances using a locally derived radiometric calibration. The TROPOMAER algorithm is based on the OMI aerosol algorithm (OMAERUV) which has been used for producing operational aerosol products for the last 14 years. In addition to the standard UV Aerosol Index (UVAI) product, TROPOMI measured radiances at 354 and 388 nm are used for retrieving Aerosol Extinction Optical Depth (AOD), Single Scattering Albedo (SSA) under cloud free conditions and above-cloud Aerosol Extinction Optical Depth (ACAOD). Collocated Suomi-NPP/VIIRS cloud mask product is also integrated with TROPOMAER for screening sub-pixel cloud contamination in the retrieved aerosol products. Initial evaluation results of TROPOMI aerosol products using AERONET AOD and SSA observations will be presented. We will also discuss preliminary results of new algorithmic approaches to retrieve aerosol layer height using TROPOMI Oxygen-B band observations, and aerosol type identification with SWIR measurements.</p>

The Kinetic Analysis of Biomass Burning Based on Two-Component Reaction Model

2012 ◽  
Vol 424-425 ◽  
pp. 1301-1304
Author(s):  
Hong Bo Lu ◽  
Ze Hui Wang ◽  
Yu Xin Ma
Keyword(s):  
Kinetic Analysis ◽  
Heating Rate ◽  
Biomass Burning ◽  
Combustion Process ◽  
Reaction Model ◽  
Experimental Results ◽  
Parallel Reaction ◽  
Heating Rates ◽  
Two Component ◽  
Good Agreement

Combustion of sawdust was studied using Pyris-1TGA thermogravimetric apparatus in the heating rates of 20, 40, 60K/min. The combustion process of sawdust includes three steps: losing water, precipitation and combustion of volatile, and carburization. A bicomponent parallel reaction model is created and used to simulate the combustion process of sawdust under the heating rate of 40K/min. Comparison of simulation and experimental results shows that the fitting curves are in good agreement with the experimental results

scholarly journals Radiative heating rate profiles over the southeast Atlantic Ocean during the 2016 and 2017 biomass burning seasons

2020 ◽  
Vol 20 (16) ◽  
pp. 10073-10090
Author(s):  
Allison B. Marquardt Collow ◽  
Mark A. Miller ◽  
Lynne C. Trabachino ◽  
Michael P. Jensen ◽  
Meng Wang
Keyword(s):  
Optical Properties ◽  
Atlantic Ocean ◽  
Biomass Burning ◽  
Single Scattering ◽  
Radiative Heating ◽  
Aerosol Layer ◽  
Aerosol Optical Properties ◽  
Ascension Island ◽  
Biomass Burning Aerosol ◽  
Aerosol Plume

Abstract. Marine boundary layer clouds, including the transition from stratocumulus to cumulus, are poorly represented in numerical weather prediction and general circulation models. Further uncertainties in the cloud structure arise in the presence of biomass burning carbonaceous aerosol, as is the case over the southeast Atlantic Ocean, where biomass burning aerosol is transported from the African continent. As the aerosol plume progresses across the southeast Atlantic Ocean, radiative heating within the aerosol layer has the potential to alter the thermodynamic environment and therefore the cloud structure; however, limited work has been done to quantify this along the trajectory of the aerosol plume in the region. The deployment of the first Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF1) in support of the Layered Atlantic Smoke Interactions with Clouds field campaign provided a unique opportunity to collect observations of cloud and aerosol properties during two consecutive biomass burning seasons during July through October of 2016 and 2017 over Ascension Island (7.96∘ S, 14.35∘ W). Using observed profiles of temperature, humidity, and clouds from the field campaign alongside aerosol optical properties from Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), as input for the Rapid Radiation Transfer Model (RRTM), profiles of the radiative heating rate due to aerosols and clouds were computed. Radiative heating is also assessed across the southeast Atlantic Ocean using an ensemble of back trajectories from the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Idealized experiments using the RRTM with and without aerosols and a range of values for the single-scattering albedo (SSA) demonstrate that shortwave (SW) heating within the aerosol layer above Ascension Island can locally range between 2 and 8 K d−1 depending on the aerosol optical properties, though impacts of the aerosol can be felt elsewhere in the atmospheric column. When considered under clear conditions, the aerosol has a cooling effect at the TOA, and based on the observed cloud properties at Ascension Island, the cloud albedo is not large enough to overcome this. Shortwave radiative heating due to biomass burning aerosol is not balanced by additional longwave (LW) cooling, and the net radiative impact results in a stabilization of the lower troposphere. However, these results are extremely sensitive to the single-scattering albedo assumptions in models.

Sign in / Sign up

Export Citation Format

Share Document