Radiative effect of surface albedo change from biomass burning

Abstract. This paper addresses the Amazonian radiative budget after considering three aspects of deforestation: (i) the emission of aerosols from biomass burning due to forest fires; (ii) changes in surface albedo after deforestation and (iii) modifications in the column water vapour amount over deforested areas. Simultaneous Clouds and the Earth's Radiant Energy System (CERES) shortwave fluxes and aerosol optical depth (AOD) retrievals from the Moderate Resolution Imaging SpectroRadiometer (MODIS) were analysed during the peak of the biomass burning seasons (August and September) from 2000 to 2009. A discrete-ordinate radiative transfer (DISORT) code was used to extend instantaneous remote sensing radiative forcing assessments into 24-h averages. The mean direct radiative forcing of aerosols at the top of the atmosphere (TOA) during the biomass burning season for the 10-yr studied period was −5.6 ± 1.7 W m−2. Furthermore, the spatial distribution of the direct radiative forcing of aerosols over Amazon was obtained for the biomass burning season of each year. It was observed that for high AOD (larger than 1 at 550 nm) the imbalance in the radiative forcing at the TOA may be as high as −20 W m−2 locally. The surface reflectance plays a major role in the aerosol direct radiative effect. The study of the effects of biomass burning aerosols over different surface types shows that the direct radiative forcing is systematically more negative over forest than over savannah-like covered areas. Values of −15.7 ± 2.4 W m−2/τ550 nm and −9.3 ± 1.7 W m−2/τ550 nm were calculated for the mean daily aerosol forcing efficiencies over forest and savannah-like vegetation respectively. The overall mean annual albedo-change radiative forcing due to deforestation over the state of Rondônia, Brazil, was determined as −7.3 ± 0.9 W m−2. Biomass burning aerosols impact the radiative budget for approximately two months per year, whereas the surface albedo impact is observed throughout the year. Because of this difference, the estimated impact in the Amazonian annual radiative budget due to surface albedo-change is approximately 6 times higher than the impact due to aerosol emissions. The influence of atmospheric water vapour content in the radiative budget was also studied using AERONET column water vapour. It was observed that column water vapour is in average smaller by about 0.35 cm over deforested areas compared to forested areas. Our results indicate that this drying impact contributes to an increase in the shortwave radiative effect that varies from 0.4 W m−2 to 1.2 W m−2, depending on the column water vapour content before deforestation. The large radiative forcing values presented in this study point out that deforestation has strong implications in convection, cloud development and photosynthesis rate over the Amazon region.

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The direct radiative effect of biomass burning aerosols over southern Africa

Atmospheric Chemistry and Physics ◽

10.5194/acp-5-1999-2005 ◽

2005 ◽

Vol 5 (7) ◽

pp. 1999-2018 ◽

Cited By ~ 50

Author(s):

S. J. Abel ◽

E. J. Highwood ◽

J. M. Haywood ◽

M. A. Stringer

Keyword(s):

Optical Properties ◽

Biomass Burning ◽

Land Surface ◽

General Circulation ◽

Surface Albedo ◽

Circulation Model ◽

Radiative Effect ◽

Aerosol Optical Properties ◽

African Region ◽

Biomass Smoke

Abstract. A multi-column radiative transfer code is used to assess the direct radiative effect of biomass burning aerosols over the southern African region during September. The horizontal distribution of biomass smoke is estimated from two sources; i) General Circulation Model (GCM) simulations combined with measurements from the Aerosol Robotic Network (AERONET) of Sun photometers; ii) data from the Moderate resolution Imaging Spectrometer (MODIS) satellite. Aircraft and satellite measurements are used to constrain the cloud fields, aerosol optical properties, vertical structure, and land surface albedo included in the model. The net regional direct effect of the biomass smoke is -3.1 to -3.6 Wm-2 at the top of atmosphere, and -14.4 to -17.0 Wm-2 at the surface for the MODIS and GCM distributions of aerosol. The direct radiative effect is shown to be highly sensitive to the prescribed vertical profiles and aerosol optical properties. The diurnal cycle of clouds and the spectral dependency of surface albedo are also shown to play an important role.

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The direct radiative effect of biomass burning aerosols over southern Africa

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-5-1165-2005 ◽

2005 ◽

Vol 5 (2) ◽

pp. 1165-1211 ◽

Cited By ~ 5

Author(s):

S. J. Abel ◽

E. J. Highwood ◽

J. M. Haywood ◽

M. A. Stringer

Keyword(s):

Optical Properties ◽

Biomass Burning ◽

Land Surface ◽

General Circulation ◽

Surface Albedo ◽

Circulation Model ◽

Radiative Effect ◽

Aerosol Optical Properties ◽

African Region ◽

Biomass Smoke

Abstract. A multi-column radiative transfer code is used to assess the direct radiative effect of biomass burning aerosols over the southern African region during September. The horizontal distribution of biomass smoke is estimated from two sources; i) General Circulation Model (GCM) simulations combined with measurements from the Aerosol Robotic Network (AERONET) of Sun photometers; ii) data from the Moderate resolution Imaging Spectrometer (MODIS) satellite. Aircraft and satellite measurements are used to constrain the cloud fields, aerosol optical properties, vertical structure, and land surface albedo included in the model. The net regional direct effect of the biomass smoke is −3.1 to −3.6 Wm-2 at the top of atmosphere, and −14.4 to −17.0 Wm-2 at the surface for the MODIS and GCM distributions of aerosol. The direct radiative effect is shown to be highly sensitive to the prescribed vertical profiles and aerosol optical properties. The diurnal cycle of clouds and the spectral dependency of surface albedo are also shown to play an important role.

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The radiative effect of an aged, internally mixed Arctic aerosol originating from lower-latitude biomass burning

Tellus B ◽

10.3402/tellusb.v61i4.16864 ◽

2009 ◽

Vol 61 (4) ◽

Cited By ~ 2

Author(s):

Ann-Christine Engvall ◽

Johan Ström ◽

Peter Tunved ◽

Radovan Krejci ◽

Hans Schlager ◽

...

Keyword(s):

Biomass Burning ◽

Lower Latitude ◽

Radiative Effect ◽

Arctic Aerosol

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Radiative forcing over the Arctic of aerosols from the August 2017 Canadian and Greenlandic wildfires

10.5194/egusphere-egu21-7405 ◽

2021 ◽

Author(s):

Filippo Calì Quaglia ◽

Daniela Meloni ◽

Alcide Giorgio di Sarra ◽

Tatiana Di Iorio ◽

Virginia Ciardini ◽

...

Keyword(s):

Radiative Transfer ◽

Radiative Forcing ◽

Solar Zenith Angle ◽

Surface Albedo ◽

High Arctic ◽

The Arctic ◽

Radiative Transfer Model ◽

Transfer Model ◽

Aerosol Layer ◽

Radiative Effect

Extended and intense wildfires occurred in Northern Canada and, unexpectedly, on the Greenlandic West coast during summer 2017. The thick smoke plume emitted into the atmosphere was transported to the high Arctic, producing one of the largest impacts ever observed in the region. Evidence of Canadian and Greenlandic wildfires was recorded at the Thule High Arctic Atmospheric Observatory (THAAO, 76.5&#176;N, 68.8&#176;W, www.thuleatmos-it.it) by a suite of instruments managed by ENEA, INGV, Univ. of Florence, and NCAR. Ground-based observations of the radiation budget have allowed quantification of the surface radiative forcing at THAAO.&#160;Excess biomass burning chemical tracers such as CO, HCN, H2CO, C2H6, and NH3 were&#160; measured in the air column above Thule starting from August 19 until August 23. The aerosol optical depth (AOD) reached a peak value of about 0.9 on August 21, while an enhancement of wildfire compounds was&#160; detected in PM10. The measured shortwave radiative forcing was -36.7 W/m2 at 78&#176; solar zenith angle (SZA) for AOD=0.626.MODTRAN6.0 radiative transfer model (Berk et al., 2014) was used to estimate the aerosol radiative effect and the heating rate profiles at 78&#176; SZA. Measured temperature profiles, integrated water vapour, surface albedo, spectral AOD and aerosol extinction profiles from CALIOP onboard CALIPSO were used as model input. The peak&#160; aerosol heating rate (+0.5 K/day) was&#160; reached within the aerosol layer between 8 and 12 km, while the maximum radiative effect (-45.4 W/m2) is found at 3 km, below the largest aerosol layer.The regional impact of the event that occurred on August 21 was investigated using a combination of atmospheric radiative transfer modelling with measurements of AOD and ground surface albedo from MODIS. The aerosol properties used in the radiative transfer model were constrained by in situ measurements from THAAO. Albedo data over the ocean have been obtained from Jin et al. (2004). Backward trajectories produced through HYSPLIT simulations (Stein et al., 2015) were also employed to trace biomass burning plumes.The radiative forcing efficiency (RFE) over land and ocean was derived, finding values spanning from -3 W/m2 to -132 W/m2, depending on surface albedo and solar zenith angle. The fire plume covered a vast portion of the Arctic, with large values of the daily shortwave RF (< -50 W/m2) lasting for a few days. This large amount of aerosol is expected to influence cloud properties in the Arctic, producing significant indirect radiative effects.

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Albedo over rough snow and ice surfaces

The Cryosphere ◽

10.5194/tc-8-1069-2014 ◽

2014 ◽

Vol 8 (3) ◽

pp. 1069-1086 ◽

Cited By ~ 33

Author(s):

S. Lhermitte ◽

J. Abermann ◽

C. Kinnard

Keyword(s):

Complex Terrain ◽

Surface Albedo ◽

Sampling Bias ◽

Mountain Glaciers ◽

Moderate Resolution ◽

Resolution Imaging ◽

Sampling Biases ◽

Moderate Resolution Imaging Spectroradiometer ◽

Mean Square Errors ◽

Effect Of Surface

Abstract. Both satellite and ground-based broadband albedo measurements over rough and complex terrain show several limitations concerning feasibility and representativeness. To assess these limitations and understand the effect of surface roughness on albedo, firstly, an intrasurface radiative transfer (ISRT) model is combined with albedo measurements over different penitente surfaces on Glaciar Tapado in the semi-arid Andes of northern Chile. Results of the ISRT model show effective albedo reductions over the penitentes up to 0.4 when comparing the rough surface albedo relative to the albedo of the flat surface. The magnitude of these reductions primarily depends on the opening angles of the penitentes, but the shape of the penitentes and spatial variability of the material albedo also play a major role. Secondly, the ISRT model is used to reveal the effect of using albedo measurements at a specific location (i.e., apparent albedo) to infer the true albedo of a penitente field (i.e., effective albedo). This effect is especially strong for narrow penitentes, resulting in sampling biases of up to ±0.05. The sampling biases are more pronounced when the sensor is low above the surface, but remain relatively constant throughout the day. Consequently, it is important to use a large number of samples at various places and/or to locate the sensor sufficiently high in order to avoid this sampling bias of surface albedo over rough surfaces. Thirdly, the temporal evolution of broadband albedo over a penitente-covered surface is analyzed to place the experiments and their uncertainty into a longer temporal context. Time series of albedo measurements at an automated weather station over two ablation seasons reveal that albedo decreases early in the ablation season. These decreases stabilize from February onwards with variations being caused by fresh snowfall events. The 2009/2010 and 2011/2012 seasons differ notably, where the latter shows lower albedo values caused by larger penitentes. Finally, a comparison of the ground-based albedo observations with Landsat and MODIS (Moderate Resolution Imaging Spectroradiometer)-derived albedo showed that both satellite albedo products capture the albedo evolution with root mean square errors of 0.08 and 0.15, respectively, but also illustrate their shortcomings related to temporal resolution and spatial heterogeneity over small mountain glaciers.

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The radiative effect of an aged, internally mixed Arctic aerosol originating from lower-latitude biomass burning

Tellus B ◽

10.1111/j.1600-0889.2009.00431.x ◽

2009 ◽

Vol 61 (4) ◽

pp. 677-684 ◽

Cited By ~ 16

Author(s):

Ann-CHRISTINE Engvall ◽

Johan StröM ◽

Peter Tunved ◽

Radovan Krejci ◽

Hans Schlager ◽

...

Keyword(s):

Biomass Burning ◽

Lower Latitude ◽

Radiative Effect ◽

Arctic Aerosol

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Biomass-burning-induced surface darkening and its impact on regional meteorology in eastern China

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-6177-2020 ◽

2020 ◽

Vol 20 (10) ◽

pp. 6177-6191 ◽

Cited By ~ 2

Author(s):

Rong Tang ◽

Xin Huang ◽

Derong Zhou ◽

Aijun Ding

Keyword(s):

Biomass Burning ◽

Surface Albedo ◽

Near Infrared ◽

Regional Climate ◽

Eastern China ◽

Weather Forecast ◽

Early Summer ◽

Adjacent Area ◽

Infrared Band ◽

Sharp Drop

Abstract. Biomass burning has attracted great concerns for the emission of particular matters and trace gases, which substantially impacts air quality, human health, and climate change. Meanwhile, large areas of dark char, carbon residue produced in incomplete combustion, can stick to the surface over fire-prone areas after open burning, leading to a sharp drop in surface albedo, so-called “surface darkening”. However, exploration into such surface albedo declines and the radiative and meteorological effects is still fairly limited. As one of the highest-yield agricultural areas, eastern China features intensive straw burning every early summer, the harvest season for winter wheat, which was particularly strong in 2012. Satellite retrievals show that the surface albedo decline over fire-prone areas was significant, especially in the near-infrared band, which can reach −0.16. Observational evidence of abnormal surface warming was found by comparing radiosonde and reanalysis data. Most sites around intensive burned scars show a positive deviation, extending especially in the downwind area. Comparisons between “pre-fire” and “post-fire” from 2007 to 2015 indicated a larger temperature bias of the forecast during the post-fire stage. The signal becomes more apparent between 14:00 and 20:00 LT. Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) simulations suggest that including surface darkening can decrease model bias and well-captured temperature variation after burning at sites in fire areas and their adjacent area. This work highlights the importance of biomass burning induced albedo change in weather forecast and regional climate.

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