Based on the high-resolution Eulerian fields of an ocean general circulation model simulation, the heat contribution of the Indonesian throughflow(ITF) to the Indian Ocean is estimated by Lagrangian tracing method.The...Based on the high-resolution Eulerian fields of an ocean general circulation model simulation, the heat contribution of the Indonesian throughflow(ITF) to the Indian Ocean is estimated by Lagrangian tracing method.The heat transport of each particle of ITF waters is calculated by tracing temperature change along the trajectory until the particle exits the Indian Ocean. The simulation reveals that the ITF waters flow westward and branch near Madagascar, further showing the ITF waters are redistributed in both northern and southern Indian Ocean.Heat budget analysis indicates that the ITF waters gain 0.41 PW(Petawatts, 1015 W) in the northern Indian Ocean and lose 0.56 PW in the southern Indian Ocean, respectively. As a result, the ITF waters warm the whole Indian Ocean basin with only 0.15 PW, which shows an "insignificant" role of ITF on the Indian Ocean because of the heat exchange compensation between northern and southern Indian Ocean. Furthermore, the tracing pathways show that the ITF waters mainly flow out the Indian Ocean at both sides of the basin via Agulhas Current and Leeuwin Current. About 89% of the ITF waters leave along western boundary and the rest 11% along eastern boundary. Compared to seeding section, 0.10 PW and 0.05 PW are released to the Indian Ocean, respectively.展开更多
The tropical Indian Ocean circulation system includes the equatorial and near-equatorial circulations, the marginal sea circulation, and eddies. The dynamic processes of these circulation systems show significant mult...The tropical Indian Ocean circulation system includes the equatorial and near-equatorial circulations, the marginal sea circulation, and eddies. The dynamic processes of these circulation systems show significant multi-scale variability associated with the Indian Monsoon and the Indian Ocean dipole. This paper summarizes the research progress over recent years on the tropical Indian Ocean circulation system based on the large-scale hydrological observations and numerical simulations by the South China Sea Institute of Oceanology(SCSIO), Chinese Academy of Sciences. Results show that:(1) the wind-driven Kelvin and Rossby waves and eastern boundary-reflected Rossby waves regulate the formation and evolution of the Equatorial Undercurrent and the Equatorial Intermediate Current;(2) the equatorial wind-driven dynamics are the main factor controlling the inter-annual variability of the thermocline in the eastern Indian Ocean upwelling;(3) the equatorial waves transport large amounts of energy into the Bay of Bengal in forms of coastal Kelvin and reflected free Rossby waves. Several unresolved issues within the tropical Indian Ocean are discussed:(i) the potential effects of the momentum balance and the basin resonance on the variability of the equatorial circulation system, and(ii) the potential contribution of wind-driven dynamics to the life cycle of the eastern Indian Ocean upwelling. This paper also briefly introduces the international Indian Ocean investigation project of the SCSIO, which will advance the study of the multi-scale variability of the tropical Indian Ocean circulation system, and provide a theoretical and data basis to support marine environmental security for the countries around the Maritime Silk Road.展开更多
水系超级电容器具有能量密度高,循环稳定性好,安全性高等优势,但低能量密度阻碍了其进一步应用.通过一种简单有效的方法得到具有高能量密度和宽电压的水系超级电容器依旧面临挑战.本工作设计了一种三氧化二钒/碳纳米空心球(H-V_(2)O_(3)...水系超级电容器具有能量密度高,循环稳定性好,安全性高等优势,但低能量密度阻碍了其进一步应用.通过一种简单有效的方法得到具有高能量密度和宽电压的水系超级电容器依旧面临挑战.本工作设计了一种三氧化二钒/碳纳米空心球(H-V_(2)O_(3)/C)电极,并将其应用于水系超级电容器.碳的引入可以提高材料的导电性和稳定性,同时空心结构有利于提高电化学活性面积,提供快速的离子传输通道.此外,这种集成电极可同时工作于正极和负极电压窗口.因此,H-V_(2)O_(3)/C集成电极在-1.1–1.3 V的电压窗口下具有708.6 F g^(-1)的比容量.基于其多重储能机制,得到的水系对称超级电容器比传统的(非)对称超级电容器具有更高的电压窗口和能量密度.在2.4 V的宽电压下工作,当功率密度为1204.6 W kg^(-1)时具有96.8 W h kg^(-1)的高能量密度,同时具有优良的循环稳定性.本研究对电极材料的设计和制备具有一定的启发意义,为开发宽电压水系超级电容器开辟了一条新途径.展开更多
Urbanization has been a worldwide development trend,which regulates river courses,impervious surfaces and drainage systems.Urbanization causes hydrological effects,including increased runoff volumes,peak discharges an...Urbanization has been a worldwide development trend,which regulates river courses,impervious surfaces and drainage systems.Urbanization causes hydrological effects,including increased runoff volumes,peak discharges and flow concentrations.This manuscript selects the Malaysian Sungai Pinang watershed as a case study to illustrate these land use,channel and flooding changes of Asian coastal cities.The Landsat satellite remote sensing images were first used to estimate the land use/land cover changes of the Sungai Pinang watershed by using SVM algorithm,and the results shows the urbanization was very rapid in the past decades,with the urbanization rate reached 46.41%in 2018 based on the build area rate.River channel characteristics also changed significantly,from natural river to concrete channel.Some flood resilience measures for coastal cities experiencing urbanization are also proposed for development and flood mitigation.Moreover,a flood forecasting model of the Sungai Pinang watershed is established herein.The simulation results of the Liuxihe model constructed in this study conforms to hydrological regularities and can provide a technical reference for flood control and disaster reduction.However,it is necessary to pay attention to the uncertainty of the forecast results.展开更多
基金The Strategic Priority Research Program of Chinese Academy of Sciences under contract Nos XDA20060502 and XDA11010301the National Key Research and Development Program of China under contract No.2016YFC1401401+2 种基金the National Natural Science Foundation of China under contract Nos 41676013,41521005 and 41731173the Independent Research Project Program of State Key Laboratory of Tropical Oceanography under contract No.LTOZZ1702the CAS/SAFEA International Partnership Program for Creative Research Teams
文摘Based on the high-resolution Eulerian fields of an ocean general circulation model simulation, the heat contribution of the Indonesian throughflow(ITF) to the Indian Ocean is estimated by Lagrangian tracing method.The heat transport of each particle of ITF waters is calculated by tracing temperature change along the trajectory until the particle exits the Indian Ocean. The simulation reveals that the ITF waters flow westward and branch near Madagascar, further showing the ITF waters are redistributed in both northern and southern Indian Ocean.Heat budget analysis indicates that the ITF waters gain 0.41 PW(Petawatts, 1015 W) in the northern Indian Ocean and lose 0.56 PW in the southern Indian Ocean, respectively. As a result, the ITF waters warm the whole Indian Ocean basin with only 0.15 PW, which shows an "insignificant" role of ITF on the Indian Ocean because of the heat exchange compensation between northern and southern Indian Ocean. Furthermore, the tracing pathways show that the ITF waters mainly flow out the Indian Ocean at both sides of the basin via Agulhas Current and Leeuwin Current. About 89% of the ITF waters leave along western boundary and the rest 11% along eastern boundary. Compared to seeding section, 0.10 PW and 0.05 PW are released to the Indian Ocean, respectively.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFC1405100)the National Natural Science Foundation of China(Grant Nos.41521005,41476011,41706027,41676013)+4 种基金the Natural Science Foundation of Guangdong(Grant No.2016A030310015)the Open Fund of the Key Laboratory of Ocean Circulation and Waves,Chinese Academy of Sciences(Grant No.KLOCW1604)the Open Fund of the State Key Laboratory of Tropical Oceanography(Grant No.LTOZZ1702)the MEL Visiting Fellowship(Grant No.MELRS1640)the Guangzhou Science and Technology Foundation(Grant No.201804010133)
文摘The tropical Indian Ocean circulation system includes the equatorial and near-equatorial circulations, the marginal sea circulation, and eddies. The dynamic processes of these circulation systems show significant multi-scale variability associated with the Indian Monsoon and the Indian Ocean dipole. This paper summarizes the research progress over recent years on the tropical Indian Ocean circulation system based on the large-scale hydrological observations and numerical simulations by the South China Sea Institute of Oceanology(SCSIO), Chinese Academy of Sciences. Results show that:(1) the wind-driven Kelvin and Rossby waves and eastern boundary-reflected Rossby waves regulate the formation and evolution of the Equatorial Undercurrent and the Equatorial Intermediate Current;(2) the equatorial wind-driven dynamics are the main factor controlling the inter-annual variability of the thermocline in the eastern Indian Ocean upwelling;(3) the equatorial waves transport large amounts of energy into the Bay of Bengal in forms of coastal Kelvin and reflected free Rossby waves. Several unresolved issues within the tropical Indian Ocean are discussed:(i) the potential effects of the momentum balance and the basin resonance on the variability of the equatorial circulation system, and(ii) the potential contribution of wind-driven dynamics to the life cycle of the eastern Indian Ocean upwelling. This paper also briefly introduces the international Indian Ocean investigation project of the SCSIO, which will advance the study of the multi-scale variability of the tropical Indian Ocean circulation system, and provide a theoretical and data basis to support marine environmental security for the countries around the Maritime Silk Road.
基金financially supported by the National Natural Science Foundation of China (NSFC, 52073137, 21704038and 51763018)the NSFC-DFG Joint Research Project (51761135114)+1 种基金the Natural Science Foundation of Jiangxi Province (20192BCB23001and 20202ZDB01009)the National Postdoctoral Program for Innovative Talents (BX201700112)
文摘水系超级电容器具有能量密度高,循环稳定性好,安全性高等优势,但低能量密度阻碍了其进一步应用.通过一种简单有效的方法得到具有高能量密度和宽电压的水系超级电容器依旧面临挑战.本工作设计了一种三氧化二钒/碳纳米空心球(H-V_(2)O_(3)/C)电极,并将其应用于水系超级电容器.碳的引入可以提高材料的导电性和稳定性,同时空心结构有利于提高电化学活性面积,提供快速的离子传输通道.此外,这种集成电极可同时工作于正极和负极电压窗口.因此,H-V_(2)O_(3)/C集成电极在-1.1–1.3 V的电压窗口下具有708.6 F g^(-1)的比容量.基于其多重储能机制,得到的水系对称超级电容器比传统的(非)对称超级电容器具有更高的电压窗口和能量密度.在2.4 V的宽电压下工作,当功率密度为1204.6 W kg^(-1)时具有96.8 W h kg^(-1)的高能量密度,同时具有优良的循环稳定性.本研究对电极材料的设计和制备具有一定的启发意义,为开发宽电压水系超级电容器开辟了一条新途径.
基金supported by the National Key Research and Development Program of China(funding no.2017YFC1502702)
文摘Urbanization has been a worldwide development trend,which regulates river courses,impervious surfaces and drainage systems.Urbanization causes hydrological effects,including increased runoff volumes,peak discharges and flow concentrations.This manuscript selects the Malaysian Sungai Pinang watershed as a case study to illustrate these land use,channel and flooding changes of Asian coastal cities.The Landsat satellite remote sensing images were first used to estimate the land use/land cover changes of the Sungai Pinang watershed by using SVM algorithm,and the results shows the urbanization was very rapid in the past decades,with the urbanization rate reached 46.41%in 2018 based on the build area rate.River channel characteristics also changed significantly,from natural river to concrete channel.Some flood resilience measures for coastal cities experiencing urbanization are also proposed for development and flood mitigation.Moreover,a flood forecasting model of the Sungai Pinang watershed is established herein.The simulation results of the Liuxihe model constructed in this study conforms to hydrological regularities and can provide a technical reference for flood control and disaster reduction.However,it is necessary to pay attention to the uncertainty of the forecast results.