DOI: 10.1002/jgrd.50754
论文题名: Water isotopic variability in response to mesoscale convective system over the tropical ocean
作者: Kurita N.
刊名: Journal of Geophysical Research Atmospheres
ISSN: 21698996
出版年: 2013
卷: 118, 期: 18 起始页码: 10376
结束页码: 10390
语种: 英语
英文关键词: amount effect
; tropical convection
; water isotopes
Scopus关键词: Climatology
; Hydrogen bonds
; Rain
; Storms
; Tropical engineering
; Tropics
; Vapors
; Amount effects
; Convective activity
; Isotopic concentrations
; Madden-Julian oscillation
; Mesoscale Convective System
; Precipitation systems
; Tropical convection
; Water isotope
; Isotopes
; climatic region
; empirical analysis
; isotopic composition
; marine ecosystem
; precipitation (climatology)
; rainfall
; stratified fluid
; tropical region
英文摘要: In tropical regions, the empirical negative relationship between the isotopic content of precipitation and rainfall amount, known as the "amount effect", has been used as a rationale for paleohydroclimate reconstruction from isotope records. However, there is still no comprehensive physical explanation for this empirical effect. Here we reconsider the well-known amount effect using newly available isotope data for both surface water vapor and precipitation obtained from shipboard observations. In this study, we hypothesized that stratiform rainfall associated with mesoscale convective systems (MCSs) is a key process in reducing tropical water isotopic concentrations and tested this hypothesis with an idealized MCS model. Our conceptual model reasonably accounted for several observed features and indicated that isotopic reductions in tropical oceanic regions reflect a precipitating system's change. Relatively high isotope ratios corresponded to disorganized convection. On the other hand, MCSs were characterized by lower isotope ratios with increasing stratiform area. In addition, the amplitude of this isotopic depletion was related to the scale of the precipitation system. The lowest isotopic ratios were observed during the passage of large-scale disturbances - corresponding to the Madden-Julian oscillation convective envelope - in which MCSs are embedded. This means that the frequent appearance of MCSs results in further decreases in the isotopic ratio of surface vapor and precipitation. From this, we conclude that the amount effect can be interpreted as the development of a precipitation system from an isolated convection cell into a large-scale system containing several MCSs and that past large-scale convective activity can be reconstructed from isotope records. Key Points Provide new data for water isotopes over the oceanProvide a key process for controlling isotopic variation in tropical waterPropose new interpretation of the ©2013. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/63306
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
Recommended Citation:
Kurita N.. Water isotopic variability in response to mesoscale convective system over the tropical ocean[J]. Journal of Geophysical Research Atmospheres,2013-01-01,118(18)