Unexpected anthropogenic emission decreases explain recent atmospheric mercury concentration declines

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(42)

Published: Oct. 8, 2024

Anthropogenic activities emit ~2,000 Mg y −1 of the toxic pollutant mercury (Hg) into atmosphere, leading to long-range transport and deposition remote ecosystems. Global anthropogenic emission inventories report increases in Northern Hemispheric (NH) Hg emissions during last three decades, contradiction with observed decline atmospheric concentrations at NH measurement stations. Many factors can obscure link between concentrations, including trends reemissions previously released (“legacy”) Hg, sink variability, spatial heterogeneity monitoring data. Here, we assess gaseous elemental (Hg 0 ) apply biogeochemical box modeling chemical understand trend drivers. Using linear mixed effects observational data from 51 stations, find negative most regions, an overall for 2005 2020 −0.011 ± 0.006 ng m −3 (±2 SD). In contrast existing inventories, our analysis suggests that annual must have declined by least 140 years be consistent trends. Faster declines 95th percentile values than median Europe, North America, East Asian stations corroborate likely cause is a nearby rather background legacy reemissions. Our results are relevant evaluating effectiveness Minamata Convention on Mercury, demonstrating incompatible declines.

Language: Английский

---

Halogen Emissions from Coal-Fired Power Plants in China: Evolutions, Driving Forces, and Future Trends

Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 16, 2025

Atmospheric halogens, including fluorine (F), chlorine (Cl), bromine (Br), and iodine(I), significantly impact atmospheric chemistry climate change. Containing all types of coal fired power plants (CFPPs) are among the major anthropogenic sources halogens. However, comprehensive estimates halogen emissions from CFPPs in China remain limited, despite significant advancements scale pollution control. This study developed a detailed inventory for halogens using multisource data mass balance method, analyzing their spatiotemporal variations, driving forces, future trends under goals. Results showed fluctuating 2018 to 2022, with F, Cl, Br, I reaching 6,875.7 t, 24,872.4 1,127.9 476.7 t respectively. Emissions were predominately concentrated key resource areas high-energy-consuming regions. Increased consumption was primary driver growth, while improvements control generation technology contributed reductions. Under air goals, expected peak before 2030 decline rapidly thereafter, near-elimination by 2050. Combining strict pollutants carbon technologies would offer greatest reduction potential.

Language: Английский

---

Anthropogenic short-lived halogens increase human exposure to mercury contamination due to enhanced mercury oxidation over continents

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(12)

Published: March 11, 2024

Mercury (Hg) is a contaminant of global concern, and an accurate understanding its atmospheric fate needed to assess risks humans ecosystem health. Atmospheric oxidation Hg key the deposition this toxic metal Earth’s surface. Short-lived halogens (SLHs) can provide halogen radicals directly oxidize perturb budget other oxidants (e.g., OH O 3 ). In addition known ocean emissions halogens, recent observational evidence has revealed abundant anthropogenic SLHs over continental areas. However, impacts on human exposure contamination remain unknown. Here, we show that inclusion substantially increased local and, consequently, in/near source regions by up 20%, thereby decreasing export from clean environments. Our modeling results indicated lead higher than estimated in previous assessments, e.g., with increases 8.7% 7.5% China India, respectively, consequently leading Hg-related health risks. These highlight urgent need for policymakers reduce emissions. We conclude substantial should be included model assessments associated at scales.

Language: Английский

---

Four Decades of Atmospheric Mercury Records at Mt. Everest Reveals Significant Reduction in Anthropogenic Mercury Emissions Over the Past Decade

ACS ES&T Air, Journal Year: 2025, Volume and Issue: unknown

Published: April 7, 2025

Language: Английский

---

Assessment of multi-year mercury concentration measurements over the South African Highveld: a case study of 2016-2023 selected dataset

Atmospheric Environment, Journal Year: 2025, Volume and Issue: unknown, P. 121261 - 121261

Published: May 1, 2025

Language: Английский

---