By extracting and comparing long-term trend components of coral gray value, sea surface temperature, cloudiness, and net heat flux for the period of 1946-1992, the relationships among them are addressed. There exists ...By extracting and comparing long-term trend components of coral gray value, sea surface temperature, cloudiness, and net heat flux for the period of 1946-1992, the relationships among them are addressed. There exists a prominent regime shift in the cloudiness associated with the corresponding variabilities of sea surface temperature and net heat flux occurred in the mid-1960s, which can be successfully recorded by coral gray value, a climatic proxy. Long-term cloudiness variations in the South China Sea are completely opposite to the equatorial western Pacific in the past five decades, whereas they share a similar trend to that over Asian monsoon prevailing waters. The fact that the coral gray value is highly correlated to cloudiness provides a unique perspective on utilizing this coral to study cloudiness variations in the pre-instrumental period.展开更多
基于2020年上半年我国东部近海站点观测资料和葵花-8卫星反演海雾产品对我国自主研发的GRAPES-TYM模式进行了海雾预报性能评估。点、面检验结果表明:模式48 h和72 h TS分别为0.40和0.36,黄海海雾预报性能最优,34°~37°N海域内...基于2020年上半年我国东部近海站点观测资料和葵花-8卫星反演海雾产品对我国自主研发的GRAPES-TYM模式进行了海雾预报性能评估。点、面检验结果表明:模式48 h和72 h TS分别为0.40和0.36,黄海海雾预报性能最优,34°~37°N海域内大部分站点TS高于0.50。黄海海雾落区预报检验显示均压场形势下预报最准确,平均临界成功指数为0.35;气旋后部海雾多空报。2 m相对湿度预报偏差具有局地性特征,相对湿度低估的站海雾预报击中率、TS相对低,反之亦然。另外,模式对成雾相关气象要素预报误差相对小且对成雾有利时海雾预报基本正确;模式预报风向较实际风向偏东南,易出现冷偏差和湿偏差,虚假的有利温湿条件导致海雾空报。展开更多
采用GFS背景场资料和ADAS资料同化系统,使用WRF模式对2014—2016年青岛近海17个海雾个例进行了模拟,分析了3种能见度算法的预报效果。结果表明,FSL(Forecast Systems Laboratory)算法对于沿海站、岸基站雾的预报较SW99(Steolinga and Wa...采用GFS背景场资料和ADAS资料同化系统,使用WRF模式对2014—2016年青岛近海17个海雾个例进行了模拟,分析了3种能见度算法的预报效果。结果表明,FSL(Forecast Systems Laboratory)算法对于沿海站、岸基站雾的预报较SW99(Steolinga and Warner 1999)算法有优势;对于海岛站而言,SW99算法则优于FSL算法。混合算法CVIS(Combined Visibility)较单一算法预报雾准确率有所提高。3种能见度算法基本上是高估能见度的,SW99算法能见度预报均方根误差最大。另外,SW99算法对沿海站、岸基站雾开始时间预报较实况多偏晚,结束时间预报较实况多偏早,持续时间预报较实况多偏短。展开更多
将柠檬酸和Super P (SP)作为碳源用喷雾干燥技术制备出具有分级结构的类球形MgFe_2O_4/C (MFO/C)复合材料,使用场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)和电化学测试等手段表...将柠檬酸和Super P (SP)作为碳源用喷雾干燥技术制备出具有分级结构的类球形MgFe_2O_4/C (MFO/C)复合材料,使用场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)和电化学测试等手段表征了样品的形貌、结构和电化学性能。结果表明,在电流密度为0.5 C (500 mA·g^(-1))的条件下这种复合材料的首次放电比容量为1162.7 mAh·g^(-1),200次循环后比容量稳定在约734.5 mAh·g^(-1)。在电流密度为1C (1000 mA·g^(-1))条件下,200次循环后比容量仍保持在约580.4 mAh·g^(-1)。具有优异的循环和倍率性能的原因,可能是SP和柠檬酸分解生成的晶粒间碳形成了良好的导电网络,使材料的导电性提高并缓解了在连续充放电过程中活性物质的团聚和体积膨胀。展开更多
The authors analyze the coral growth band from a colony in the northwestern South China Sea. The coral growth band can provide comprehensive environmental information on climate. The trend from the two-century-long an...The authors analyze the coral growth band from a colony in the northwestern South China Sea. The coral growth band can provide comprehensive environmental information on climate. The trend from the two-century-long annual density of the coral is in a good agreement with that of the global CO2 concentration. Both trends were small prior to the end of the 19th century; after that, trends became clear, more so from the 1960s to the 1990s (the end of the coral record). The overall coral density shows a steady decrease from the late 19th century to the late 20th century. Therefore, the trend from the annual density of the coral reveals the history of the anthropogenic climate change, which is coherent with instrumental and other proxy records. We propose a simple coral-based proxy for reconstructing the anthropogenic climate change over the past two centuries.展开更多
The interdecadal variation of coral grayness in northern South China Sea (SCS) is studied using the annual mean coral grayness in northern SCS from 1789 to 1992 and annual precipitation at Guangzhou from 1908 to 1992 ...The interdecadal variation of coral grayness in northern South China Sea (SCS) is studied using the annual mean coral grayness in northern SCS from 1789 to 1992 and annual precipitation at Guangzhou from 1908 to 1992 by Singular Spectrum Analysis (SSA), correlation analysis, Mann-Kendall’s abrupt change analysis and composite analysis. The interdecadal variation of south China precipitation as reflected by the series of Guangzhou precipitation rebuilt with the coral grayness is discussed. The results show that the variation of coral grayness in SCS has significant terms of tendency, much-weighted interdecadal variation and weak interannual variation. There was a century-scale abrupt change of coral grayness at the end of the 1880s that changed from positive anomalies to negative anomalies. The global field of SST difference corresponding to the point of abrupt change was negative anomalies over the SCS and neighboring northern Indian Ocean, most of central and western Pacific Ocean and coastal areas of the northern Atlantic Ocean. The large-scale distribution of SST anomalies is concomitant with the century-scale abrupt change of coral grayness in SCS. Negative correlation exists between the coralgrayness in SCS and precipitation in Guangzhou on the interdecadal scale and the interdecadal precipitation in Guangzhou as reflected by the interdecadaldata of SCS coral grayness shows that the interdecadal variation of south China precipitation changes significantly from phase to phase. The current study aims at contributing in the effort of identifying alternative indexes for climate change in south China on the interdecadal scale and beyond.展开更多
基金This research was supported by the National Natural Science Foundation of China under contract Nos 40136010 and 40305009the Guangdong Science Foundation under contract No.04001308.The authors thank the anonymous reviewers for their comments and suggestions.
文摘By extracting and comparing long-term trend components of coral gray value, sea surface temperature, cloudiness, and net heat flux for the period of 1946-1992, the relationships among them are addressed. There exists a prominent regime shift in the cloudiness associated with the corresponding variabilities of sea surface temperature and net heat flux occurred in the mid-1960s, which can be successfully recorded by coral gray value, a climatic proxy. Long-term cloudiness variations in the South China Sea are completely opposite to the equatorial western Pacific in the past five decades, whereas they share a similar trend to that over Asian monsoon prevailing waters. The fact that the coral gray value is highly correlated to cloudiness provides a unique perspective on utilizing this coral to study cloudiness variations in the pre-instrumental period.
文摘基于2020年上半年我国东部近海站点观测资料和葵花-8卫星反演海雾产品对我国自主研发的GRAPES-TYM模式进行了海雾预报性能评估。点、面检验结果表明:模式48 h和72 h TS分别为0.40和0.36,黄海海雾预报性能最优,34°~37°N海域内大部分站点TS高于0.50。黄海海雾落区预报检验显示均压场形势下预报最准确,平均临界成功指数为0.35;气旋后部海雾多空报。2 m相对湿度预报偏差具有局地性特征,相对湿度低估的站海雾预报击中率、TS相对低,反之亦然。另外,模式对成雾相关气象要素预报误差相对小且对成雾有利时海雾预报基本正确;模式预报风向较实际风向偏东南,易出现冷偏差和湿偏差,虚假的有利温湿条件导致海雾空报。
文摘采用GFS背景场资料和ADAS资料同化系统,使用WRF模式对2014—2016年青岛近海17个海雾个例进行了模拟,分析了3种能见度算法的预报效果。结果表明,FSL(Forecast Systems Laboratory)算法对于沿海站、岸基站雾的预报较SW99(Steolinga and Warner 1999)算法有优势;对于海岛站而言,SW99算法则优于FSL算法。混合算法CVIS(Combined Visibility)较单一算法预报雾准确率有所提高。3种能见度算法基本上是高估能见度的,SW99算法能见度预报均方根误差最大。另外,SW99算法对沿海站、岸基站雾开始时间预报较实况多偏晚,结束时间预报较实况多偏早,持续时间预报较实况多偏短。
基金supported by Knowledge Innovation Program of Chinese Academy of Sciences (Grant No. KZSW2-YW-214)National Key Basic Research and Development Program of China (Grant No. 2006CB403604)National Natural Science Foundation of China (Grant Nos. U0733002 and 40906010)
文摘The authors analyze the coral growth band from a colony in the northwestern South China Sea. The coral growth band can provide comprehensive environmental information on climate. The trend from the two-century-long annual density of the coral is in a good agreement with that of the global CO2 concentration. Both trends were small prior to the end of the 19th century; after that, trends became clear, more so from the 1960s to the 1990s (the end of the coral record). The overall coral density shows a steady decrease from the late 19th century to the late 20th century. Therefore, the trend from the annual density of the coral reveals the history of the anthropogenic climate change, which is coherent with instrumental and other proxy records. We propose a simple coral-based proxy for reconstructing the anthropogenic climate change over the past two centuries.
文摘The interdecadal variation of coral grayness in northern South China Sea (SCS) is studied using the annual mean coral grayness in northern SCS from 1789 to 1992 and annual precipitation at Guangzhou from 1908 to 1992 by Singular Spectrum Analysis (SSA), correlation analysis, Mann-Kendall’s abrupt change analysis and composite analysis. The interdecadal variation of south China precipitation as reflected by the series of Guangzhou precipitation rebuilt with the coral grayness is discussed. The results show that the variation of coral grayness in SCS has significant terms of tendency, much-weighted interdecadal variation and weak interannual variation. There was a century-scale abrupt change of coral grayness at the end of the 1880s that changed from positive anomalies to negative anomalies. The global field of SST difference corresponding to the point of abrupt change was negative anomalies over the SCS and neighboring northern Indian Ocean, most of central and western Pacific Ocean and coastal areas of the northern Atlantic Ocean. The large-scale distribution of SST anomalies is concomitant with the century-scale abrupt change of coral grayness in SCS. Negative correlation exists between the coralgrayness in SCS and precipitation in Guangzhou on the interdecadal scale and the interdecadal precipitation in Guangzhou as reflected by the interdecadaldata of SCS coral grayness shows that the interdecadal variation of south China precipitation changes significantly from phase to phase. The current study aims at contributing in the effort of identifying alternative indexes for climate change in south China on the interdecadal scale and beyond.
