Yiquan Qi

Hohai University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Shiqiu Peng

Institute of Oceanology

Rongyu Chen

Guangxi University

Zhijin Li

University of California, Los Angeles

Xuezhi Zeng

Zhiyou Jing

South China Sea Institute Of Oceanology

Yan Du

South China Sea Institute Of Oceanology

Xuhua Cheng

Hubei University

Xuhua Cheng

Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)

Youfang Yan

South China Sea Institute Of Oceanology

Bo Qiu

University of Hawaiʻi at Mānoa

Cooperative Institutions

Chinese Academy of Sciences

Institute of Oceanology

South China Sea Institute Of Oceanology

Ministry of Natural Resources

University of Chinese Academy of Sciences

Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)

Hohai University

Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)

Qingdao National Laboratory for Marine Science and Technology

Ocean University of China

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

SST Front Anchored Mesoscale Feature of Surface Wind in the Southern Indian Ocean

AGU Fall Meeting Abstracts (2018)

Xia Huang Xuhua Cheng Yiquan Qi

Using 28-year satellite-borne Special Sensor Microwave Imager observations, features of high-wind frequency (HWF) over the southern Indian Ocean are investigated. Climatology maps show that high winds occur frequently during austral winter, located in the open ocean south of Polar Front in subpolar region, warm flank of the Subantarctic Front between 55°E–78°E, and south of Cape Agulhas, where westerly wind prevails. The strong instability of marine atmospheric boundary layer accompanied by increased sensible and latent heat fluxes on the warmer flank acts to enhance the vertical momentum mixing, thus accelerate the surface winds. Effects of sea surface temperature (SST) front can even reach the entire troposphere by deep convection. HWF also shows distinct interannual variability, which is associated with the Southern Annual Mode (SAM). During positive phase of the SAM, HWF has positive anomalies over the open ocean south of Polar Front, while has negative anomalies north of the SST front. A phase shift of HWF happened around 2001, which is likely related to the reduction of storm tracks and poleward shift of westerly winds in the Southern Hemisphere.

Polar front

Westerlies

Cold front

Source

Cite

Citations (0)

Joint Probability Analysis of Numerical Simulation Results of Typhoon Wave and Storm Surge of the Wulei Station at the Beibu Bay

Marine Science Bulletin (2006)

Yiquan Qi

In this paper, by employing the numerical simulation results of typhoon wave and storm surge from 1949 to 2002 of the Wulei station at the Beibu Bay, their extreme-values of time series of 54 years were obtained. We found that the distribution of joint probability between the extreme-values of typhoon wave and storm surge is an exponential distribution, then we use GUMBEL Ⅱ joint probability function to fit to it. During finding out the function, we got extreme- values of typhoon wave, storm surge, their extreme-values of joint probability distribution of different recurrence periods and corresponding probabilities, respectively . The result was perfect, and of some reference value to marine engineering design.

Typhoon

Storm Surge

Gumbel distribution

Significant wave height

Wave height

Source

Cite

Citations (5)

Journal of Oceanography (2000)

Jianyu Hu Hiroshi Kawamura Huasheng Hong Yiquan Qi

Anticyclone

Eddy

Circulation (fluid dynamics)

China sea

10.1023/a:1011117531252

Cite

Citations (684)

Interannual and interdecadal variability of the North Equatorial Countercurrent in the Western Pacific

Journal of Geophysical Research Oceans (2016)

Xiao Chen Bo Qiu Yan Du Shuiming Chen Yiquan Qi

Abstract Interannual and longer timescale variations of the North Equatorial Countercurrent (NECC) in the western Pacific are investigated using the multidecade (1960–2014) hindcast by the Ocean general circulation model for the Earth Simulator (OFES). The OFES‐simulated sea level and upper ocean circulation changes show favorable comparisons with available tide gauge data and repeat hydrographic surveys along the 137°E meridian. An empirical orthogonal function (EOF) analysis reveals that the low‐frequency NECC variability is dominated by two distinct modes. The first mode fluctuates interannually and shows strengthening and southward migration of the NECC concurrent with the development of El Niño events. Unlike the extratropical western Pacific Ocean circulation variability controlled by wind forcing west of the dateline, the interannual NECC variations are forced by equatorial wind forcing cumulative across the entire Pacific basin. The second mode of the NECC variability has an interdecadal timescale and is characterized by NECC's progressive weakening in strength, migrating poleward, and broadening in width over the past 50 years. These long‐term changes in NECC are caused by the corresponding changes in the trade wind system that weakened and expanded poleward in the past half a century across the Pacific basin.

Empirical orthogonal functions

Hindcast

Forcing (mathematics)

Boundary current

10.1002/2016jc012190

Cite

Citations (26)

Evaluation of an ocean data assimilation system for Chinese marginal seas with a focus on the South China Sea

Chinese Journal of Oceanology and Limnology (2011)

Dazhi Xu Xichen Li Jiang Zhu Yiquan Qi

Drifter

Sea-surface height

Anticyclone

Ocean observations

10.1007/s00343-011-0044-4

Cite

Citations (14)

Determination of the South China Sea surface height variability using TOPEX/POSEIDON data

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE (2004)

Peter C. Chu Jing Wang Yiquan Qi

The monthly mean TOPEX/POSEIDON crossover data in the South China Sea are used to investigate the spatial and temporal variability of sea surface height anomaly (SSHA). Multi-time scale variability is found using the empirical orthogonal function (EOF) analysis. The seasonal variability dominates SSHA with two spatial patterns: basin-wide gyre and north-south double gyres. The intraseasonal variability of SSH has high spatial variability at the continental s helf such as west of Hainan Island and Borneo, and east-west double gyre structure in the deep basin. The interannual variability of SSHA has a north-south double gyre pattern. The scale interaction between seasonal interannual processes may be taken at the north-south double gyre pattern.

Sea-surface height

Empirical orthogonal functions

Anomaly (physics)

10.1117/12.509063

Cite

Citations (3)

South China Sea Wind-Wave Characteristics. Part I: Validation of Wavewatch-III Using TOPEX/Poseidon Data

Journal of Atmospheric and Oceanic Technology (2004)

Peter C. Chu Yiquan Qi Yuchun Chen Ping Shi Qingwen Mao

Abstract A full-spectral third-generation ocean wind-wave model, Wavewatch-III, has been implemented in the South China Sea (SCS) for investigating wind-wave characteristics. This model was developed at the Ocean Modeling Branch of the National Centers for Environmental Prediction (NCEP). The NASA QuickSCAT data (0.25° resolution) 2 times daily were used to simulate the wind waves for the entire year of 2000. The significant wave heights from Wavewatch-III are compared to the TOPEX/Poseidon (T/P) significant wave height data over the satellite crossover points in SCS. The model errors of significant wave height have Gaussian-type distribution with a small mean value of 0.02 m (almost no bias). The model errors are comparable to the T/P altimeter accuracy (0.5 m) in the central SCS and are smaller than the T/P altimeter accuracy in the northern and southern SCS, which indicates the capability of Wavewatch-III for SCS wave simulation.

Significant wave height

Wave model

Wind wave model

Wave height

10.1175/jtech1661.1

Cite

Citations (85)

Scale Transition From Geostrophic Motions to Internal Waves in the Northern South China Sea

Journal of Geophysical Research Oceans (2019)

Haijin Cao Zhiyou Jing Baylor Fox‐Kemper Yan Tong Yiquan Qi

Abstract The eddy‐abundant circulation in the northern South China Sea (NSCS) tends to be dynamically complex due to monsoon forcing, Kuroshio intrusion, and emitted internal waves from the Luzon Strait. This study uses 13‐year shipboard acoustic Doppler current profiler measurements (2004–2016), orbital altimeter data, and high‐resolution model output to perform wave‐vortex decompositions and investigate the scale of transition from dominantly geostrophic flows to internal wave motions in the northern South China Sea. The upper ocean kinetic energy spectra transition on scales exceeds 200 km. This large scale of transition is attributed to the energetic low‐mode internal waves (e.g., internal tides and inertia‐gravity waves). However, inconsistencies in the decomposition reveal that the assumptions of homogeneity and isotropy required for the 1‐D decomposition (Bühler et al., 2014) are sufficiently violated at smaller scales to affect the subdominant member of the decomposition on scales below 100 km. A method for direct quantification of the consequences by degree of violation using bootstrapping of the 2‐D model data is developed and illustrated. Observed and modeled sea surface height spectra flatten at scales smaller than 125 km, which is found in the model to be due to the coherent, semidiurnal internal waves. The large scale of transition between geostrophic and wave motions in the South China Sea is an irreducible uncertainty for altimeter velocities (e.g., the Surface Water and Ocean Topography mission).

Sea-surface height

Geostrophic current

10.1029/2019jc015575

Cite

Citations (32)

REDOS_1.0_1994.tar.bz2: An ocean reanalysis dataset of the South China Sea (REDOS) in 1994

Figshare (2014)

Yiquan Qi Rongyu Chen Xuezhi Zeng Shiqiu Peng Zhijin Li

An ocean reanalysis dataset of the South China Sea (REDOS) in 1994

tar (computing)

China sea

10.6084/m9.figshare.1164585_d4