Stable isotope ratios of typhoon rains in Fuzhou, Southeast China, during 2013–2017
Journal
Journal of Hydrology
Journal Volume
570
Pages
445
Date Issued
2019
Author(s)
Tao Xu
Xiaoshuang Sun
Hui Hong
Xiaoyan Wang
Mengyue Cui
Guoliang Lei
Lu Gao
Juan Liu
Abstract
© 2019 Elsevier B.V. Stable isotope ratios (δ 2 H and δ 18 O) in precipitation not only show a certain response to climate change at different time scales, but also have strong linkages to extreme weather events such as tropical cyclones (hurricanes/typhoons). Typhoon activity in the coastal region of Southeast China is quite intense, bringing huge amounts of moisture; thus, contributing to extreme rainfall in this region. The existing isotope data in Southeast China is available on a monthly or daily temporal resolution, which is inadequate to study 1–2-day-long typhoon rainfall events at a particular location. In this study, hourly rainfall δ 2 H and δ 18 O data are collected for eight typhoon events from 2013 to 2017 in Fuzhou, Southeast China. The total correlation between δ 2 H and δ 18 O is obtained as δ 2 H = 7.41 δ 18 O + 0.81 (R 2 = 0.96, N = 220). All the eight typhoon events reveal a similar variability pattern in δ 18 O values which can be divided into three stages. More positive δ 18 O values occur in the first and third stages, while the second stage is dominated by most negative δ 18 O values, exhibiting an inverted U-shaped pattern. The positive δ 18 O values during the first and third stages are governed by re-evaporation. The precipitation during the second stage has distinctly lower δ 18 O values than the weighted average δ 18 O of summer precipitation in Fuzhou. Some of these values are slightly lower than those of the water vapor over the Pacific Ocean's surface. No significant relationship is observed between precipitation δ 18 O and temperature as well as the amount of precipitation during the second stage. We hypothesize that the significant 18 O-depletion is mainly caused by the ‘rain shield effect’ which refers to combination of large-scale convection, high condensation efficiency, and recycling of isotopically depleted vapor in rain shield areas leading to very negative δ 18 O values during typhoon system. These findings suggest the use of stable isotope ratios as important tracers of typhoon water.
Subjects
Typhoon; Rainfall; Stable Isotope ratios; Southeast China; Rain shield effect
Other Subjects
Climate change; Isotopes; Rain; Storms; Condensation efficiency; Different time scale; Extreme weather events; Hurricanes/typhoons; Southeast China; Stable isotope ratios; Summer precipitation; Variability patterns; Hurricanes; climate change; isotopic ratio; oxygen isotope; precipitation (climatology); rainfall; stable isotope; tropical cyclone; typhoon; United Nations Framework Convention on Climate Change; China; Fujian; Fuzhou; Pacific Ocean
Publisher
Elsevier {BV}
Type
journal article