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2024
2017
2013
Black Carbon Emission Reduction Due to COVID-19 Lockdown in China
During the Lunar New Year Holiday of 2020, China implemented an unprecedented lockdown to fight the COVID-19 outbreak, which strongly affected the anthropogenic emissions. We utilized elemental carbon observations (equivalent to black carbon, BC) from 42 sites and performed inverse modeling to determine the impact of the lockdown on the weekly BC emissions and quantify the effect of the stagnant conditions on BC observations in densely populated eastern and northern China. BC emissions declined 70% (eastern China) and 48% (northern China) compared to the first half of January. In northern China, under the stagnant conditions of the first week of the lockdown, the observed BC concentrations rose unexpectedly (29%) even though the BC emissions fell. The emissions declined substantially thereafter until a week after the lockdown ended. On the contrary, in eastern China, BC emissions dropped sharply in the first week and recovered synchronously with the end of the lockdown.
American Geophysical Union (AGU)
2021
Black carbon and ionic species in the Arctic aerosol.
Previous studies on Arctic aerosol characteristics have shown a pronounced winter-spring maximum and summer-autumn minimum in aerosol concentration. Measurements of black carbon concentration in the atmospheric aerosol were obtained by means of an aethalometer at the Zeppelinfjellet station Ny-¿lesund, Svalbard. Simultaneous 24 hour measurements of the concentration of key aerosol species like sulphate, ammonium and nitrate together with sulphur dioxide, conducted by NILU are presented and discussed in order to evaluate the transport processes governing their presence in the High Arctic. Large variations are seen to be superimposed on an overall trend that apparently exhibits higher values in winter than in late summer. Back trajectory analysis of the airmasses arriving at Zeppelin station, reveals that enhanced concentrations observed for black carbon and sulphate are associated with long range transport of polluted air from Eurasia. Black carbon, sulphur dioxide and sulphate concentrations are correlated well. Nitrate and ammonium display a rather poor association with the above species and between each other.
2001
2016
2024
2023
2006
2013
Bird feathers as a biomonitor for environmental pollutants: Prospects and pitfalls
Due to increasing amounts of hazardous chemicals released into the environment, there is a high demand for developing easy and non-destructive biomonitoring tools. In a recent paper published in Trends in Analytical Chemistry, Rutkowska et al. (2018) concluded that feathers are a good matrix for biomonitoring of environmental pollutants in birds. In this commentary, we discuss the general conclusion of this paper. We provide several examples for which this statement is not correct, and we emphasize that only for legacy persistent organic pollutants (POPs) and mercury there is currently enough scientific evidence to use feathers as a reliable biomonitor, given that appropriate sampling designs and QA/QC protocols are taken into account. Furthermore, we discuss different pretreatment (e.g. feather washing) and analytical protocols along with specific QA/QC to be considered. In summary, this commentary provides an overview of the prospects and pitfalls when using feathers as a biomonitor for environmental pollutants.
2019
2006
2010
Biotic and abiotic transformation pathways of synthetic musks in the aquatic environment. Handbook of environmental chemistry, Vol. 3X, Anthropogenic compounds
2004
2015