DOI: 10.1016/j.epsl.2020.116518
论文题名: Improving the estimate of the secular variation of Greenland ice mass in the recent decades by incorporating a stochastic process
作者: Zhang B. ; Liu L. ; Yao Y. ; van Dam T. ; Abbas Khan S.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2020
卷: 549 语种: 英语
中文关键词: Greenland
; interannual variations
; secular mass changes
; stochastic process
英文关键词: Acceleration
; Climate change
; Climate models
; Glacial geology
; Gravitation
; Ice
; Parameter estimation
; Random processes
; Stochastic systems
; Conventional methods
; Conventional modeling
; Deterministic component
; Gravity recovery and climate experiment datum
; Greenland Ice Sheet
; Interannual variation
; Stochastic component
; Surface mass balance
; Stochastic models
; acceleration
; discharge
; estimation method
; GRACE
; ice sheet
; mass balance
; quantitative analysis
; satellite data
; secular variation
; stochasticity
; Arctic
; Greenland
; Greenland Ice Sheet
英文摘要: The irregular interannual variations observed in the Greenland ice sheet (GrIS) mass balance can be interpreted as stochastic. These variations often have large amplitudes, and, if not accounted for correctly in the mass change model parameterization, could have profound impacts on the estimate of the secular trend and acceleration. Here we propose a new mass trajectory model that includes both the conventional deterministic components and a stochastic component. This new model simultaneously estimates the secular rate and acceleration, seasonal components, and the stochastic component of mass changes. Simulations show that this new model improves estimates of model parameters, especially accelerations, over the conventional model without stochastic component. Using this new model, we estimate an acceleration of −1.6 ± 1.3 Gt/yr2 in mass change (minus means mass loss) for 2003-2017 using the Gravity Recovery and Climate Experiment (GRACE) data and an acceleration of −1.1 ± 1.3 Gt/yr2 using the modeled surface mass balance plus observed ice discharge. The corresponding rates are estimated to be −288.2 ± 12.7 Gt/yr and −274.9 ± 13.0 Gt/yr. The greatest discrepancies between the new and the conventional model parameter determinations are found in the acceleration estimates, −1.6 Gt/yr2 vs. −7.5 Gt/yr2 from the GRACE data. The estimated accelerations using the new method are apparently smaller than those estimated by other studies in terms of mass loss. Our quantitative analysis elucidates that the acceleration estimate using the conventional method is the lower bound (i.e., −7.5 Gt/yr2 for 2003–2017) while the acceleration estimated by the new method lies in the middle of the possible ranges. It is also found that these discrepancies between the new and the conventional methods diminish with sufficiently long (>20 yr) observation records. © 2020 The Author(s) Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165377
Appears in Collections: 气候变化与战略
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作者单位: School of Geodesy and Geomatics, Wuhan University, Wuhan, 430079, China; Earth System Science Programme, The Chinese University of Hong Kong, Shatin, Hong Kong; Faculty of Science, Technology, and Communication, University of Luxembourg, Luxembourg City, Luxembourg; DTU Space-National Space Institute, Technical University of Denmark, Department of Geodesy, Kgs. Lyngby, Denmark
Recommended Citation:
Zhang B.,Liu L.,Yao Y.,et al. Improving the estimate of the secular variation of Greenland ice mass in the recent decades by incorporating a stochastic process[J]. Earth and Planetary Science Letters,2020-01-01,549