Biomass Burning in the Global Environment: First Results from the IGAC/BIBEX Field Campaign STARE/TRACE-A/SAFARI-92

Abstract An intensive observation period was conducted in September 2017 in the central Namib, Namibia, as part of the project Namib Fog Life Cycle Analysis (NaFoLiCA). The purpose of the field campaign was to investigate the spatial and temporal patterns of the coastal fog that occurs regularly during nighttime and morning hours. The fog is often linked to advection of a marine stratus that intercepts with the terrain up to 100 km inland. Meteorological data, including cloud base height, fog deposition, liquid water path, and vertical profiles of wind speed/direction and temperature, were measured continuously during the campaign. Additionally, profiles of temperature and relative humidity were sampled during five selected nights with stratus/fog at both coastal and inland sites using tethered balloon soundings, drone profiling, and radiosondes. This paper presents an overview of the scientific goals of the field campaign; describes the experimental setup, the measurements carried out, and the meteorological conditions during the intensive observation period; and presents first results with a focus on a single fog event.

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Anonymous review of "Evaluation of biomass burning aerosols in the HadGEM3 climate model with observations from the SAMBBA field campaign" by BT Johnson et al.

10.5194/acp-2016-442-rc1 ◽

2016 ◽

Author(s):

Anonymous

Keyword(s):

Biomass Burning ◽

Climate Model ◽

Field Campaign

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

10.5194/acp-2020-106 ◽

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.

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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

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-8233-2021 ◽

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.

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Overview and first results of the Wind and Storms Experiment (WASTEX): a field campaign to observe the formation of gusts using a Doppler lidar

Advances in Science and Research ◽

10.5194/asr-15-91-2018 ◽

2018 ◽

Vol 15 ◽

pp. 91-97 ◽

Cited By ~ 4

Author(s):

Florian Pantillon ◽

Andreas Wieser ◽

Bianca Adler ◽

Ulrich Corsmeier ◽

Peter Knippertz

Keyword(s):

Small Scale ◽

Extratropical Cyclones ◽

Doppler Lidar ◽

Winter Storms ◽

Field Campaign ◽

Layer Structures ◽

First Results ◽

Strong Winds ◽

Upper Rhine ◽

Waste Deposit

Abstract. Wind gusts are responsible for most damages in winter storms over central Europe, but capturing their small scale and short duration is a challenge for both models and observations. This motivated the Wind and Storms Experiment (WASTEX) dedicated to investigate the formation of gusts during the passage of extratropical cyclones. The field campaign took place during the winter 2016–2017 on a former waste deposit located close to Karlsruhe in the Upper Rhine Valley in southwest Germany. Twelve extratropical cyclones were sampled during WASTEX with a Doppler lidar system performing vertical scans in the mean wind direction and complemented with a Doppler C-band radar and a 200 m instrumented tower. First results are provided here for the three most intense storms and include a potential sting jet, a unique direct observation of a convective gust and coherent boundary-layer structures of strong winds.

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Response to reviewer #1 comments on: Evaluation of biomass burning aerosols in the HadGEM3 climate model with observations from the SAMBBA field campaign

10.5194/acp-2016-442-ac1 ◽

2016 ◽

Author(s):

Ben Johnson

Keyword(s):

Biomass Burning ◽

Climate Model ◽

Field Campaign

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Empirical ozone production in the subtropical UTLS from South American biomass burning during SOUTHTRAC

10.5194/egusphere-egu2020-12585 ◽

2020 ◽

Author(s):

Peter Hoor ◽

Daniel Kunkel ◽

Hans-Christoph Lachnitt ◽

Heiko Bozem ◽

Vera Bense ◽

...

Keyword(s):

South America ◽

Biomass Burning ◽

Cross Sections ◽

Ozone Production ◽

South American ◽

Air Masses ◽

First Results ◽

Tropopause Region ◽

Large Fires ◽

Flight Level

The biomass burning season in America was exceptionally intense during summer 2019. Particularly in the subtropics biomass burning potentially contributes significantly to the trace gas budget of the upper troposphere and can affect chemistry and composition far from the source.During the SOUTHTRAC mission, which took place in September and November 2019, several cross sections from the equator to the southern tip of south America were flown at typical altitudes of 13-14 km. During the northbound flight on October, 7th 2019 massive enhancements of pollutants were observed at these altitudes. Notably, in-situ observations show continuously elevated CO values exceeding 200 ppbv over a flight distance of more than 1000 km. These massive enhancements were accompanied by largely elevated NO and NOy as well as CO2 and could be attributed to the large fires in South America during this time. Observations of C2H2 and PAN from GLORIA show, that pollution covered a layer extending from 8-9 km to the flight level at 13 km.Comparing the tracer observations to previous flights in exactly the same region three weeks earlier, we could estimate the ozone production due to the biomass burning. Based on first results we estimate ozone production in the polluted air masses up to 30-40 ppbv in the UT which is almost 40% of the observed ozone mixing ratio. Given the large extent of the polluted area over 15 degrees of latitude this may have an impact on the local energy budget of the tropopause region. &#160;&#160;&#160;

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Relative humidity fields in the Annecy Alpine valley observed by Ro-Vibrational Raman lidar in the framework of L-WAIVE

10.5194/egusphere-egu2020-17672 ◽

2020 ◽

Author(s):

Alexandre Baron ◽

Patrick Chazette ◽

Julien Totems

Keyword(s):

Relative Humidity ◽

Ground Level ◽

Calibration Procedure ◽

Lidar Measurement ◽

Raman Lidar ◽

Field Campaign ◽

Alpine Valley ◽

Spectral Filtration ◽

First Results ◽

Ground Based Lidar

In June 2019, the Lacustrine-Water vApor Isotope inVentory Experiment (L-WAIVE) has been performed in the southern part of the Annecy lake (45&#176;47' N, 6&#176;12' E). The field campaign motivation is to bring a better comprehension on the evaporation processes above Alpine lakes influencing, along with orography, the complex atmospheric structuration. In particular, this two-week field campaign has involved the meteorological Raman lidar WALI (Weather and Aerosol LIdar). An ultra-light aircraft carrying a meteorological probe and a particle sizer performed several vertical profiles above the ground-based Raman lidar with a vertical resolution between 50 and 100 m for flights operated from the ground level (~0.5 km above the mean sea level (AMSL)) and ~4 km AMSL.This setup is an opportunity to experimentally assess the instrumental errors on both the temperature and the water vapour mixing ratio profiles derived from the ground-based lidar. The methodology used to calculate the error budget will be presented. It will take into account the different types of statistical noises associated with the lidar measurement. In particular, the importance of the spectral filtration in the accuracy of the results will be discussed. The uncertainties associated with the lidar calibration procedure will be quantified. Following this detailed study, the first results of relative humidity will be presented, taking into account the associated error bars.

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