Ice cap functioned as a sink for radioactive contaminant in the Tibetan Plateau: Evidence from plutonium isotopes.

J Hazard Mater

Qilian Alpine Ecology and Hydrology Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.

Published: December 2024

Cryoconite is abundant in artificial radionuclides such as plutonium (Pu) and amounts of radioactive contaminants is stored in glaciers. Under global warming and glaciers rapid retreating, glaciers could be a second source for radioactive contaminants and the stored Pu isotopes could be released to the downstream areas through surface runoff. However, the knowledge and understanding on the migration behavior and cycling of Pu isotopes in the ice cap is quite limited. In the present work, we analyzed the Pu/Pu atom ratio and Pu activity concentration in suspended particulate matter (SPM) and distribution coefficient (K) was estimated in glacier runoff in August-one ice cap, northeast Tibetan Plateau. The results showed the lower Pu activity concentration in SPM can be attributed to the content of organic matter. The Pu/Pu atom ratios in SPM (0.176-0.204), glacial meltwater (0.175-0.200) and proglacial sediments (0.172-0.180) were remarkably higher than that determined in the cryoconite samples (0.064-0.199), suggesting that radioactive Pu in the cryoconite sourced from close-in fallout (Chinese nuclear test) besides the global fallout. Due to the obtained lower K, lower activity concentrations and relatively higher Pu/Pu atom ratios in SPM, we conclude the August-one ice cap currently functions as a sink instead of source for radioactive Pu under climatic warming, and we highlight the necessity for monitoring the dynamic changes of radioactivity for long term in environmental samples in glaciers.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2024.136791DOI Listing

Publication Analysis

Top Keywords

ice cap
16
pu/pu atom
12
tibetan plateau
8
radioactive contaminants
8
contaminants stored
8
source radioactive
8
activity concentration
8
august-one ice
8
lower activity
8
atom ratios
8

Similar Publications

Cryoconite is abundant in artificial radionuclides such as plutonium (Pu) and amounts of radioactive contaminants is stored in glaciers. Under global warming and glaciers rapid retreating, glaciers could be a second source for radioactive contaminants and the stored Pu isotopes could be released to the downstream areas through surface runoff. However, the knowledge and understanding on the migration behavior and cycling of Pu isotopes in the ice cap is quite limited.

View Article and Find Full Text PDF

Kamchatka (southeastern Siberia) ice core records of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls since 1690s: A signal for the tropospheric oxidizing capacity.

Sci Total Environ

January 2025

Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan; Chubu Institute for Advanced Studies, Chubu University, Kasugai, Japan. Electronic address:

There has been much interest about how to identify an ice core signal for oxidizing capacity of the troposphere. This study broadly explains the air-snow transfer/deposition process using ice core records of dicarboxylic (DCAs), ω-oxocarboxylic as well as pyruvic acids and α-dicarbonyls, which are potentially formed by atmospheric oxidation of aromatic hydrocarbons from the continent, incloud-oxidation of isoprene and unsaturated fatty acids from the western North Pacific. An ice core (~152 m long, 304 years) was collected at an ice cap on the Gorshkov crater at the summit of Ushkovsky (56° 04'N, 160° 28'E, altitude: 3903 m) in the Kamchatka Peninsula from southeastern Siberia.

View Article and Find Full Text PDF
Article Synopsis
  • Glaciers in the Arctic have significantly lost mass over the past two decades, particularly through processes at glacier calving fronts which remain poorly understood due to limited long-term data.
  • Researchers studied Austfonna, the largest ice cap in Svalbard, using satellite data and in-situ ocean records from 2018-2022, revealing that calving and melting mainly occur in autumn.
  • Ocean temperature plays a crucial role in glacier ablation, while the impact of subglacial meltwater runoff is minimal, indicating that marine-terminating glaciers may rapidly respond to seasonal ocean changes influenced by warmer Atlantic waters.
View Article and Find Full Text PDF
Article Synopsis
  • * Researchers detected 36 types of PFAS in the surface snow of the Arctic island of Spitsbergen during 2019, indicating widespread contamination, especially from local sources with some levels up to 54 times higher in populated areas.
  • * The study found that seasonal changes in sunlight significantly affect the formation and deposition of certain PFAS, suggesting that photochemical processes are key in the Arctic atmosphere's pollution dynamics.
View Article and Find Full Text PDF

Lithium isotope evidence for a plumeworld ocean in the aftermath of the Marinoan snowball Earth.

Proc Natl Acad Sci U S A

November 2024

Department of Geosciences, Virginia Tech, Blacksburg, VA 24061.

Article Synopsis
  • The snowball Earth hypothesis suggests that during the Marinoan ice age around 635 million years ago, continental chemical weathering was greatly reduced but then increased afterward.
  • Research conducted on lithium isotope compositions in rock layers from South China shows a distinct trend of decreasing lithium levels as distance from the shore increases, indicating the mixing of meltwater and hypersaline seawater.
  • The findings support the idea that during this period, weak weathering on land and strong reverse weathering on the ocean floor influenced the chemistry of the oceans, aligning with the plumeworld hypothesis.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!