Spatial-Temporal Variation of Snow Black Carbon Concentration in Snow Cover in Northeast China from 2001 to 2016 Based on Remote Sensing

The amount of black carbon (BC) on snow surface can significantly reduce snow surface albedo in the visible-light range and change the surface radiative forcing effect. Therefore, it is key to study regional and global climate changes to understand the BC concentration on snow. In this study, we simulated the BC concentration on the surface snow of northeast China using an asymptotic radiative transfer model. From 2001 to 2016, the BC concentration showed no significant increase, with an average increase of 82.104 ng/g compared with that in the early 21st century. The concentration of BC in December was the largest (1344.588 ng/g) and decreased in January and February (1248.619 ng/g and 983.635 ng/g, respectively). The high black carbon content centers were concentrated in the eastern and central regions with dense populations and concentrated industries, with a concentration above 1200 ng/g, while the BC concentration in the southwest region with less human activities was the lowest (below 850 ng/g), which indicates that human activities played an important role in snow BC pollution. Notably, Heilongjiang province has the highest concentration, which may be related to its atmospheric stability in winter. These findings suggest that the BC pollution in northeast China has been aggravated from 2001 to 2016. It is estimated that the snow surface albedo will decrease by 16.448% due to the BC pollution of snow in northeast China. The problem of radiative forcing caused by black carbon to snow reflectivity cannot be ignored.

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Snow Surface Albedo Sensitivity to Black Carbon: Radiative Transfer Modelling

Atmosphere ◽

10.3390/atmos11101077 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1077

Author(s):

Nicholas D. Beres ◽

Magín Lapuerta ◽

Francisco Cereceda-Balic ◽

Hans Moosmüller

Keyword(s):

Radiative Transfer ◽

Black Carbon ◽

Surface Albedo ◽

Mass Density ◽

Radiative Transfer Model ◽

Transfer Model ◽

Snow Surface ◽

Snow Albedo ◽

Carbon Mass ◽

The Relationship

The broadband surface albedo of snow can greatly be reduced by the deposition of light-absorbing impurities, such as black carbon on or near its surface. Such a reduction increases the absorption of solar radiation and may initiate or accelerate snowmelt and snow albedo feedback. Coincident measurements of both black carbon concentration and broadband snow albedo may be difficult to obtain in field studies; however, using the relationship developed in this simple model sensitivity study, black carbon mass densities deposited can be estimated from changes in measured broadband snow albedo, and vice versa. Here, the relationship between the areal mass density of black carbon found near the snow surface to the amount of albedo reduction was investigated using the popular snow radiative transfer model Snow, Ice, and Aerosol Radiation (SNICAR). We found this relationship to be linear for realistic amounts of black carbon mass concentrations, such as those found in snow at remote locations. We applied this relationship to measurements of broadband albedo in the Chilean Andes to estimate how vehicular emissions contributed to black carbon (BC) deposition that was previously unquantified.

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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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Anthropogenic aerosol forcing under the Shared Socioeconomic Pathways

10.5194/acp-2019-606 ◽

2019 ◽

Author(s):

Marianne T. Lund ◽

Gunnar Myhre ◽

Bjørn H. Samset

Keyword(s):

Air Pollution ◽

Radiative Forcing ◽

Global Climate ◽

Radiative Transfer Model ◽

Transfer Model ◽

Air Pollution Control ◽

Anthropogenic Aerosols ◽

Anthropogenic Aerosol ◽

Aerosol Radiative Forcing ◽

Aerosol Forcing

Abstract. Emissions of anthropogenic aerosols are expected to change drastically over the coming decades, with potentially significant climate implications. Using the most recent generation of harmonized emission scenarios, the Shared Socioeconomic Pathways (SSPs) as input to a global chemistry transport and radiative transfer model, we provide estimates of the projected future global and regional burdens and radiative forcing of anthropogenic aerosols under three different levels of air pollution control: strong (SSP1), medium (SSP2) and weak (SSP3). We find that the broader range of future air pollution emission trajectories spanned by the SSPs compared to previous scenarios translates into total aerosol forcing estimates in 2100 relative to 1750 ranging from −0.04 W m−2 in SSP1-1.9 to −0.51 W m−2 in SSP3-7.0. Compared to our 1750–2015 estimate of −0.61 W m−2, this shows that depending on the success of air pollution policies over the coming decades, aerosol radiative forcing may weaken by nearly 95 % or remain close to the pre-industrial to present-day level. In all three scenarios there is a positive forcing in 2100 relative to 2015, from 0.51 W m−2 in SSP1-1.9 to 0.04 W m−2 in SSP3-7.0. Results also demonstrate significant differences across regions and scenarios, especially in South Asia and Africa. While rapid weakening of the negative aerosol forcing following effective air quality policies will unmask more of the greenhouse gas-induced global warming, slow progress on mitigating air pollution will significantly enhance the atmospheric aerosol levels and risk to human health. In either case, the resulting impacts on regional and global climate can be significant.

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Using surface remote sensors to derive mixed-phase cloud radiative forcing: an example from M-PACE

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-12487-2011 ◽

2011 ◽

Vol 11 (4) ◽

pp. 12487-12518 ◽

Cited By ~ 1

Author(s):

G. de Boer ◽

W. D. Collins ◽

S. Menon ◽

C. N. Long

Keyword(s):

Radiative Forcing ◽

Surface Albedo ◽

The United States ◽

Surface Fluxes ◽

Mixed Phase ◽

Department Of Energy ◽

Radiative Transfer Model ◽

Transfer Model ◽

United States Department ◽

Cloud Radiative Forcing

Abstract. A suite of ground-based measurements are used in conjunction with a column version of the Rapid Radiative Transfer Model (RRTMG) to derive the cloud radiative forcing of mixed-phase stratiform clouds observed during the United States Department of Energy (US DOE) Atmospheric Radiation Measurement (ARM) Mixed-Phase Arctic Clouds Experiment (M-PACE) between September and November of 2004. In total, sixteen half hour time periods are reviewed due to their coincidence with radiosonde launches. Cloud liquid (ice) water paths are found to range between 11.0–366.4 (0.5–114.1) gm−2, and cloud physical thicknesses fall between 286–2075 m. Combined with temperature and hydrometeor size estimates, this information is used to calculate surface radiative fluxes using RRTMG, which are demonstrated to generally agree with measured fluxes from surface-based radiometric instrumentation. Errors in longwave flux estimates are found to be largest for thin clouds, while shortwave flux errors are generally largest for thicker clouds. Cloud radiative forcing is calculated for all profiles, and illustrates the dominance of the longwave component during this time of year, with net cloud forcing generally between 50 and 90 Wm−2. Finally, sensitivity of calculated surface fluxes to droplet effective radius, surface albedo and surface temperature are tested, with changes in minimum droplet size between 3.5 and 10 μm altering the surface shortwave flux by up to 50 Wm−2, and changes in surface albedo between 0.5 and 0.95 altering surface shortwave fluxes by up to 85 Wm−2.

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Uncertainties in Radiative Forcing due to Surface Albedo Changes Caused by Land-Use Changes

Journal of Climate ◽

10.1175/1520-0442-16.10.1511 ◽

2003 ◽

Vol 16 (10) ◽

pp. 1511-1524 ◽

Cited By ~ 87

Author(s):

Gunnar Myhre ◽

Arne Myhre

Keyword(s):

Land Use ◽

Radiative Forcing ◽

Surface Albedo ◽

Land Use Changes ◽

Climate Forcing ◽

Radiative Transfer Model ◽

Transfer Model ◽

Forcing Mechanisms ◽

Global Datasets ◽

Global Mean

Abstract A radiative transfer model has been used for estimating the radiative forcing due to land-use changes. Five global datasets for current vegetation cover and three datasets of preagriculture vegetation have been adopted. The vegetation datasets have been combined with three datasets for surface albedo values. A distinct feature in all the calculations is the negative radiative forcing at the northern midlatitudes due to the conversion of forest to cropland. Regionally the radiative forcing is likely to be among the strongest of the climate forcing mechanisms. A wider range is estimated for the global mean radiative forcing due to land-use changes than previously reported. The single most important factor yielding the large range in estimated forcing is the cropland surface albedo values. This underlines the importance of characterizing surface albedo correctly.

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Black Carbon Aerosol Characteristics and Its Radiative Impact over Nainital: A High-Altitude Station in the Central Himalayas

Journal of the Institute of Engineering ◽

10.3126/jie.v8i3.5926 ◽

1970 ◽

Vol 8 (3) ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

AK Srivastava ◽

P Pant ◽

UC Dumka ◽

P Hegde

Keyword(s):

High Altitude ◽

Black Carbon ◽

Radiative Forcing ◽

Lower Atmosphere ◽

Radiative Transfer Model ◽

Transfer Model ◽

Central Himalayas ◽

Radiative Impact ◽

Potential Factor ◽

Black Carbon Aerosol

Ground-based measurements of aerosol black carbon (BC), from a high altitude location at Nainital in the central Himalayas (during June 2006 to May 2007), were used to study its temporal variability and impact on the atmospheric radiative forcing. Diurnal variation of BC mass concentration shows single enhanced peak in the late afternoon hour. The peak is rather pronounced in winter months due to shallow and stable boundary layer condition, which is largely associated with low surface temperature. The mean BC mass concentrations were found to be as ~0.6 (±0.2), 1.4 (±0.1), 1.2 (±0.3) and 1.5 (±0.2) μg m-3 during monsoon, post-monsoon, winter and spring periods, respectively while its maximum value was ~1.8 (±0.8) μg m-3 during April. The prevailing winds revealed to facilitates the transport of BC from the distant sources to the observing site. A radiative transfer model was used in conjunction with an aerosol optical model to estimate the BC radiative forcing over the station. Results show BC forcing at the top-of-atmosphere (TOA), surface and in the atmosphere varies between about +3 to +7, -6 to -14 and +8 to +21 Wm-2, respectively which is more pronounced during spring then during monsoon depending upon BC mass loading. The positive atmosphere forcing represents a considerable amount of heating to the lower atmosphere and has been conjectured as potential factor causing global warming. The estimated heating rate of the lower atmosphere over the station was found to be ranging from 0.24 Kday-1 during monsoon to 0.58 Kday-1 during spring season. DOI: http://dx.doi.org/10.3126/jie.v8i3.5926 JIE 2011; 8(3): 1-10

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The effects of additional black carbon on Arctic sea ice surface albedo: variation with sea ice type and snow cover

The Cryosphere Discussions ◽

10.5194/tcd-7-943-2013 ◽

2013 ◽

Vol 7 (2) ◽

pp. 943-973

Author(s):

A. A. Marks ◽

M. D. King

Keyword(s):

Sea Ice ◽

Snow Cover ◽

Black Carbon ◽

Surface Albedo ◽

Arctic Sea Ice ◽

Radiative Transfer Model ◽

First Year ◽

Transfer Model ◽

Ice Surface ◽

Carbon Additions

Abstract. Black carbon in sea ice will decrease sea ice surface albedo through increased absorption of incident solar radiation, exacerbating sea ice melting. Previous literature has reported different albedo responses to additions of black carbon in sea ice and has not considered how a snow cover may mitigate the effect of black carbon in sea ice. Sea ice is predominately snow covered. Visible light absorption and light scattering coefficients are calculated for a typical first year and multi-year sea ice and "dry" and "wet" snow types that suggest black carbon is the dominating absorbing impurity. The albedo response of first year and multi-year sea ice to increasing black carbon, from 1–1024 ng g−1, in a top 5 cm layer of a 155 cm thick sea ice was calculated using the radiative transfer model: TUV-snow. Sea ice albedo is surprisingly unresponsive to black carbon additions up to 100 ng g−1 with a decrease in albedo to 98.7% of the original albedo value due to an addition of 8 ng g−1 of black carbon in first year sea ice compared to an albedo decrease to 99.6% for the same black carbon mass ratio increase in multi-year sea ice. The first year sea ice proved more responsive to black carbon additions than the multi-year ice. Comparison with previous modelling of black carbon in sea ice suggests a more scattering sea ice environment will be less responsive to black carbon additions. Snow layers on sea ice may mitigate the effects of black carbon in sea ice. "Wet" and "dry" snow layers of 0.5, 1, 2, 5 and 10 cm were added onto the sea ice surface and the snow surface albedo calculated with the same increase in black carbon in the underlying sea ice. Just a 0.5 cm layer of snow greatly diminishes the effect of black carbon on surface albedo, and a 2–5 cm layer (less than half the e-folding depth of snow) is enough to "mask" any change in surface albedo owing to additional black carbon in sea ice, but not thick enough to ignore the underlying sea ice.

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Anthropogenic aerosol forcing under the Shared Socioeconomic Pathways

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-13827-2019 ◽

2019 ◽

Vol 19 (22) ◽

pp. 13827-13839 ◽

Cited By ~ 6

Author(s):

Marianne T. Lund ◽

Gunnar Myhre ◽

Bjørn H. Samset

Keyword(s):

Air Pollution ◽

Radiative Forcing ◽

Socioeconomic Development ◽

Global Climate ◽

Radiative Transfer Model ◽

Transfer Model ◽

Anthropogenic Aerosols ◽

Anthropogenic Aerosol ◽

Pollution Levels ◽

Aerosol Forcing

Abstract. Emissions of anthropogenic aerosols are expected to change drastically over the coming decades, with potentially significant climate implications. Using the most recent generation of harmonized emission scenarios, the Shared Socioeconomic Pathways (SSPs) as input to a global chemistry transport and radiative transfer model, we provide estimates of the projected future global and regional burdens and radiative forcing of anthropogenic aerosols under three contrasting pathways for air pollution levels: SSP1-1.9, SSP2-4.5 and SSP3-7.0. We find that the broader range of future air pollution emission trajectories spanned by the SSPs compared to previous scenarios translates into total aerosol forcing estimates in 2100 relative to 1750 ranging from −0.04 in SSP1-1.9 to −0.51 W m−2 in SSP3-7.0. Compared to our 1750–2015 estimate of −0.55 W m−2, this shows that, depending on the success of air pollution policies and socioeconomic development over the coming decades, aerosol radiative forcing may weaken by nearly 95 % or remain close to the preindustrial to present-day level. In all three scenarios there is a positive forcing in 2100 relative to 2015, from 0.51 in SSP1-1.9 to 0.04 W m−2 in SSP3-7.0. Results also demonstrate significant differences across regions and scenarios, especially in South Asia and Africa. While rapid weakening of the negative aerosol forcing following effective air quality policies will unmask more of the greenhouse-gas-induced global warming, slow progress on mitigating air pollution will significantly enhance the atmospheric aerosol levels and risk to human health in these regions. In either case, the resulting impacts on regional and global climate can be significant.

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No Surface Cooling over Antarctica from the Negative Greenhouse Effect Associated with Instantaneous Quadrupling of CO2 Concentrations

Journal of Climate ◽

10.1175/jcli-d-17-0418.1 ◽

2017 ◽

Vol 31 (1) ◽

pp. 317-323 ◽

Cited By ~ 5

Author(s):

Karen L. Smith ◽

Gabriel Chiodo ◽

Michael Previdi ◽

Lorenzo M. Polvani

Keyword(s):

Greenhouse Effect ◽

Radiative Forcing ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Radiative Transfer Model ◽

Transfer Model ◽

Surface Cooling ◽

Model Calculations ◽

Co2 Concentrations

Abstract Over the highest elevations of Antarctica, during many months of the year, air near the surface is colder than in much of the overlying atmosphere. This unique feature of the Antarctic atmosphere has been shown to result in a negative greenhouse effect and a negative instantaneous radiative forcing at the top of the atmosphere , when carbon dioxide (CO2) concentrations are increased, and it has been suggested that this effect might play some role in te recent cooling trends observed over East Antarctica. Here, using fully coupled global climate model integrations, in addition to radiative transfer model calculations, the authors confirm the existence of such a negative over parts of Antarctica in response to an instantaneous quadrupling of CO2. However, it is also shown that the instantaneous radiative forcing at the tropopause is positive. Further, the negative lasts only a few days following the imposed perturbation, and rapidly disappears as the stratosphere cools in response to increased CO2. As a consequence, like the , the stratosphere-adjusted radiative forcing at the TOA is positive over all of Antarctica and, in the model presented herein, surface temperatures increase everywhere over that continent in response to quadrupled CO2. The results, therefore, clearly demonstrate that the curious negative instantaneous radiative forcing plays no role in the recently observed East Antarctic cooling.

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Measurement report: Quantifying source contribution and radiative forcing of fossil fuel and biomass burning black carbon aerosol in the southeastern margin of Tibetan Plateau

10.5194/acp-2020-408 ◽

2020 ◽

Author(s):

Huikun Liu ◽

Qiyuan Wang ◽

Li Xing ◽

Yong Zhang ◽

Ting Zhang ◽

...

Keyword(s):

Tibetan Plateau ◽

Black Carbon ◽

Biomass Burning ◽

Radiative Forcing ◽

Fossil Fuel ◽

Sampling Site ◽

Radiative Transfer Model ◽

Transfer Model ◽

Southeastern Margin ◽

Fuel Source

Abstract. Black carbon (BC) aerosol plays a vital role in disturbing the balance of ecosystem and climate stability of Tibetan Plateau (TP). An intensive campaign was carried out from 14th March to 12th May 2018 in the southeastern margin of TP to investigate the sources of BC and their radiative effects. To do so, an improved aethalometer model was used to distinguish and apportion BC into fossil fuel combustion source and biomass burning source. To minimize the uncertainty associated with the aethalometer model, a receptor model coupling multi-wavelength absorption with chemical species was used to retrieve the site-dependent Ångström exponent (AAE) and BC mass absorption cross-section (MAC). The results show that the AAEs and BC MACs at wavelength of 880 nm were 0.9 and 12.3 m2 g−1 for fossil fuel source and 1.7 and 10.4 m2 g−1 for biomass burning, respectively. Based on these parameters, the fossil fuel source-related BC (BCfossil) was estimated 43 % of the total BC and the rest 57 % was from biomass burning (BCbiomass) during the campaign. The results from a regional chemical dynamical model reveal that high BCbiomass was contributed from the northeastern India and northern Burma, and the Southeast Asia can explain 40 % of BCbiomass. The high BCfossil was mainly identified from the southeast of sampling site. A radiative transfer model estimated that the atmospheric directive radiative forcing of BC was +4.6 ± 2.4 W m−2 on average, including +2.5 ± 1.8 W m−2 from BCbiomass, and +2.1 ± 0.9 W m−2 from BCfossil, which correspond to and heating rates of 0.07 ± 0.05 and 0.06 ± 0.02 K day−1, respectively. Our study will be useful for improving our understanding in BC sources on the TP and their climatic effect.

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