We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Northward Extent of Atmospheric Mercury Transboundary Transport to the Himalayas and Tibetan Plateau Region.
- Authors
Huang, Jie; Kang, Shichang; Feng, Xinbin; Tang, Wenjun; Ram, Kirpa; Guo, Junming; Zhang, Qianggong; Sharma, Chhatra Mani; Li, Chaoliu; Tripathee, Lekhendra; Wang, Feiyue
- Abstract
Indian monsoon circulation is the primary driver of the long‐range transboundary mercury (Hg) pollution from South Asia to the Himalayas and Tibet Plateau region, yet the northward extent of this transport remains unknown. In this study, a strong δ202Hg signature overlapping was found between Lake Gokyo and Indian anthropogenic sources, which is an indicative of the Hg source regions from South Asia. Most of the sediment samples were characterized with relatively large positive Δ199Hg values (mean = 0.07‰–0.44‰) and small positive Δ200Hg values (mean = 0.03‰–0.08‰). Notably, the Δ199Hg values in the lake sediments progressively increased from southwest to northeast. Moreover, the Δ199Hg values peaked at Lake Tanglha (mean = 0.44‰ ± 0.04‰) before decreased at Lake Qinghai that is under the influence of the westerlies. Our results suggest that transboundary atmospheric transport could transport Hg from South Asia northwards to at least the Tanglha Mountains in the northern Himalaya‐Tibet. Plain Language Summary: The fragile ecosystems of the Himalayas and Tibet Plateau region have been suffering transboundary Hg pollution from South Asia. However, the northward extent of this transport of atmospheric Hg pollution remains poorly understood. In our study, sediment core Hg isotope compositions from four lakes (Gokyo, Namco, and Tanglha in the south of the Tanglha Mountains and Qinghai in the north) along a southwest‐northeast transect in the region were combined to constrain the northward extent of transboundary Hg pollution by examining both mass‐dependent and mass‐independent fractionations. Our results suggest that transboundary atmospheric transport could transport Hg from South Asia northwards to at least the Tanglha Mountains in the northern Himalaya‐Tibet. Key Points: The δ202Hg signatures among the three lakes in the north are indistinguishable without spatial distribution differencesMost of sediment samples were characterized by positive Δ199Hg and Δ200Hg valuesThe northward extent of atmospheric mercury transboundary transport could be anchored by progressive shifts of Δ199Hg signatures
- Subjects
SOUTH Asia; HIMALAYA Mountains; TIBET (China); ATMOSPHERIC mercury; TRANSBOUNDARY pollution; ATMOSPHERIC transport; LAKE sediments; AIR pollution; SEDIMENT sampling
- Publication
Geophysical Research Letters, 2023, Vol 50, Issue 4, p1
- ISSN
0094-8276
- Publication type
Article
- DOI
10.1029/2022GL100948