福建东山湾海浪现场观测的统计特征

为分析福建省南部港湾──东山湾的波浪特征,采用S4型压力式方向波浪仪观测获取现场一个月的风浪过程资料,对其进行了统计分析和频谱分析,给出了波高和周期分布,特征波要素与频谱关系,结果表明:实测波高分布与瑞利分布基本相符;波浪谱的显著部分在狭窄的频率内,对应3、5、6、7级风谱峰密度值(m2s)分别为0.084 3、0.372 8、0.941 8、1.837 7,随着风速的增加,谱能也显著地增加,谱曲线下面的总面积增大,谱的显著部分波及的频率范围也扩大,且谱的显著部分沿低频率的方向推移,对应风浪的波高及周期范围增大.     

Relationship between the tropical cyclone genesis over the Northwest Pacific and the sea surface temperature anomalies

Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.     

Relationship between the tropical cyclone genesis over the Northwest Pacific and the sea surface temperature anomalies

Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.     

试析环境演变对史前人类文明发展的影响--以长江三角洲南部平原良渚古文化衰变为例

良渚先民受自然环境的制约和经济生活模式的决定,连片成串地集中分布于长江三角洲南部平原,良渚早中期的温干气候和适宜环境使良渚文化空前繁荣,但在距今4000年左右突然消亡.作者通过研究,发现在距今4100年左右存在明显的降温事件,降温使农作物歉收,食物匮乏,在部落间引起连绵战争,使良渚文化走向衰弱.而距今3600年左右的海平面升高,在长江三角洲南部平原发生沟谷海侵,地下水位升高,太湖湖泊体系迅速扩张,引起大洪水,导致良渚文化消亡.     

扩频雷达探测一阶海洋回波

利用扩频通信良好的抗干扰性和低功率谱密度下工作的特点，本文把扩频技术引入高频海洋探测雷达来探测海洋一阶回波，研究结果表明，该技术对回波质量无不良影响，同时可降低雷达发射功率，增加雷达探测距离．     

鲁西陆表海高分辨层序地层及海平面变动控制

依据钻孔岩芯和测进资料，对钽西陆表海盆地含煤地层进行了高分辨率层序划分，研究了高分辨率层序地层特点及其控制因素。研究表明，鲁西表海沉积序列中不同级次旋回相互叠加，具有特征的低频（Ⅱ～Ⅲ级）和高频（Ⅳ～Ⅵ级）层序叠加样式；这种相互叠加的旋回结构受控于相互叠置的海平面变化周期，即复合海平面变化。海平面变化周期表现出非对称式突发性上升到缓慢回落的节律性，形成了不对称的旋回记录。     

蒙山顶峰观日出海上的季节与日期研究

从天文地理的角度对蒙山顶峰观日出海上的季节与日期进行了计算研究。通过计算知，在蒙顶是可以看到日出海上的，且可能看到日出海上的日期多达２２０多元，但由于受地貌和天气双重因素的影响。在蒙顶实际可见到日出海上的日数仅剩９８天，即在蒙顶实际能看到日出海上的季节为冬至及其前后。     

Effects of clouds, sea surface temperature, and its diurnal variation on precipitation efficiency

The effects of clouds, sea surface temperature, and its diurnal variation on precipitation efficiency are investigated using grid-scale data from nine equilibrium sensitivity cloud-resolving model experiments driven without large-scale vertical velocity. The precipitation efficiencies are respectively defined in surface rainfall, cloud, and rain microphysical budgets. We mathematically and physically demonstrate the relationship between these precipitation efficiencies. The 2℃ increases in spatiotemporal invariant sea surface temperature (SST) from 27℃ to 29℃ and from 29℃ to 31℃, and the inclusion of diurnal SST difference 1℃ and the 1℃ increase in diurnal SST difference generate opposite changes in the precipitation efficiency by changing ice cloud-radiation interactions. The radiative and microphysical processes of ice clouds have opposite effects on the precipitation efficiency because of the rainfall increase associated with the reduction in the saturation mixing ratio caused by the exclusion of radiative effects and the decrease in rainfall related to the reduction in net condensation caused by the exclusion of deposition processes. The radiative effects of water clouds on the precipitation efficiency are statistically insensitive to the radiative effects of ice clouds.     

中国北方海区AIS应用研究

研究了AIS在中国北方海区的四种应用,提出应得到海事主管机关更多关注的四方面问题,分析各方面问题的根源以及潜在的和现时的影响.引入四种新理念和建议以应对目前AIS在中国北方海区应用中显现的问题.认为AIS不适宜单独应用于海事安全管理,而需要和其他助航手段和理念的结合.