Black carbon footprint of human presence in Antarctica

Cordero, Raúl R.; Sepulveda, Edgardo; Féron, Sarah; Damiani, Alessandro; Fernandoy, Francisco; Neshyba, Steven; Rowe, Penny M.; Asencio, Valentina; Carrasco, Jorge; Alfonso, Juan A.; Llanillo, P. J.; Wachter, Paul; Seckmeyer, Günther; Stepanova, M. V.; Carrera, Juan Manuel; Jorquera, José; Wang, Chenghao; Malhotra, Avni; Dana, Jacob; Khan, Alia L.; Casassa, Gino

doi:10.1038/s41467-022-28560-w

Cited by 36 publications

(12 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When we compare these model findings to the observational rBC data in the surface hoar and snow, we see the rBC concentration in fresh snow, 3 µg-rBC/L-H2O, is high compared to pristine fresh snow previously found in Svalbard, 1 µg-rBC/L-H2O (Khan et al, 2017). The average rBC concentration across the light, medium and dark patches is also relatively high for a non-human impacted site in the polar regions (Cordero et al, 2022). A previous study of black carbon in supra-glacial melt from the same GRIS site previously confirmed the dissolved BC molecular signature was indicative of wildfire smoke that likely came from Northern Canada and Alaska (Khan et al, 2017).…”

Section: Naaps Aerosol Model Comparison and Evaluation 231mentioning

confidence: 58%

Black carbon concentrations and modeled smoke deposition fluxes to the bare ice dark zone of the Greenland Ice Sheet

Khan¹,

Xian²,

Schwarz³

2023

Preprint

View full text Add to dashboard Cite

Abstract. Ice-albedo feedbacks in the ablation region of the Greenland Ice Sheet (GrIS) are difficult to constrain and model due in part to our limited understanding of the seasonal evolution of the bare-ice region. To help fill observational gaps, 13 surface samples were collected on the GrIS across the 2014 summer melt season from patches of snow that were visibly light, medium, and dark colored. These samples were analyzed for their refractory black carbon (rBC) concentrations and size distributions with a Single Particle Soot Photometer coupled to a characterized nebulizer. We present a size distribution of rBC in fresh snow on the GrIS, as well as from surface hoar in the bare ice dark zone of the GrIS. The size distributions from the surface hoar samples appear unimodal, and were overall smaller than the fresh snow sample, with a peak around 0.3 µm. The fresh snow sample contained very large rBC particles that had a pronounced bimodality in peak size distributions, with peaks around 0.2 µm and 2 µm. rBC concentrations ranged from a minimum of 3 µg-rBC/L-H2O in light-colored patches at the beginning and end of the melt season, to a maximum of 32 µg-rBC/L-H2O in a dark patch in early August. On average, rBC concentrations were higher (20 µg-rBC/L-H2O ± 10 µg-rBC/L-H2O) in patches that were visibly dark compared to medium patches (7 µg-rBC/L-H2O ± 2 µg-rBC/L-H2O) and light patches (4 µg-rBC/L-H2O ± 1 µg-rBC/L-H2O), suggesting BC aggregation contributed to snow aging on the GrIS, and vice versa. Additionally, concentrations peaked in light and dark patches in early August, which is likely due to smoke transport from wildfires in Northern Canada and Alaska as supported by the Navy Aerosol Analysis and Prediction System (NAAPS) reanalysis model. According to model output, 26 mg/m3 of biomass burning derived smoke was deposited between April 1st and August 30th, of which 85 % came from wet deposition and 67 % was deposited during our sample collection timeframe. The increase in rBC concentration and size distributions immediately after modelled smoke deposition fluxes suggest biomass burning smoke is a source of BC to the dark zone of the GRIS. Thus, role of BC in the seasonal evolution of the ice-albedo feedback should continue to be investigated in the bare-ice zone of the GrIS.

show abstract

Section: Naaps Aerosol Model Comparison and Evaluation 231mentioning

confidence: 58%

Black carbon concentrations and modeled smoke deposition fluxes to the bare ice dark zone of the Greenland Ice Sheet

Khan¹,

Xian²,

Schwarz³

2023

Preprint

View full text Add to dashboard Cite

show abstract

“…The initial success of a logistic-sharing trial in the Antarctic Peninsula, organised by the Council of Managers of National Antarctic Programs (COMNAP), demonstrates the potential of such approaches [ 73 ], though noting that the use of some infrastructure is already oversubscribed. Improving transport management by better utilising transport infrastructure and technology to reduce transport or black carbon pollution [ 74 , 75 ], and by optimising routes and timing to minimise wildlife disturbance [ 76 ] is another feasible and low-cost strategy. The International Association of Antarctica Tour Operators (IAATO) has commenced taking steps in this direction by establishing 2 “go-slow” whale zones in the Antarctic Peninsula region [ 77 ].…”

Section: Resultsmentioning

confidence: 99%

Threat management priorities for conserving Antarctic biodiversity

et al. 2022

View full text Add to dashboard Cite

Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations.

show abstract

“…Our array of ice cores suggests a strong spatial gradient with high deposition in low-elevation East Greenland for all three impurities – microscopic charcoal, black carbon, and lead. Significant deposition of dark, light-absorbing particles on the Greenland ice sheet may ultimately result in changes of the snow surface albedo (Cordero et al, 2022; Doherty et al, 2010; Kang et al, 2020; Stohl, 2006) and induce feedback mechanisms with warming climate that in turn may result in more frequent high-latitude boreal forest and Tundra fires (Bond et al, 2013).…”

Section: Discussionmentioning

confidence: 99%

High-latitude fire activity of recent decades derived from microscopic charcoal and black carbon in Greenland ice cores

et al. 2022

View full text Add to dashboard Cite

Warming temperatures and prolonged drought periods cause rapid changes of fire frequencies and intensities in high-latitude ecosystems. Associated smoke plumes deposit dark particles from incomplete combustion on the Greenland ice sheet that reduce albedo but also provide a detailed record of paleofire history. Here, we apply an emerging microscopic charcoal technique in combination with established black carbon and lead pollution measurements to an array of 10 ice cores from southern to central Greenland that span recent decades. We found that microscopic charcoal deposition is highly variable among sites, with a few records suggesting recently increasing biomass burning possibly in response to growing fire activity in boreal forest ecosystems. This stands in contrast to decreasing trends in black carbon measured in the same ice cores, consistent with contributions from industrial fossil fuel emissions. Decreasing trends of lead pollution and occurrence of microscopic spheroidal carbonaceous particles (SCP), a microfossil tracer of fossil fuel emissions, further support our interpretation that black carbon in this region is influenced by industrial emissions during recent decades. We conclude that microscopic charcoal analyses in ice may help disentangle biomass burning from fossil-fuel emissions during the industrial period and have potential to contribute to better understanding of regional high-latitude fire regimes.

show abstract

Black carbon footprint of human presence in Antarctica

Cited by 36 publications

References 51 publications

Black carbon concentrations and modeled smoke deposition fluxes to the bare ice dark zone of the Greenland Ice Sheet

Black carbon concentrations and modeled smoke deposition fluxes to the bare ice dark zone of the Greenland Ice Sheet

Threat management priorities for conserving Antarctic biodiversity

High-latitude fire activity of recent decades derived from microscopic charcoal and black carbon in Greenland ice cores

Contact Info

Product

Resources

About