海气交换与海气边界层观测研究进展

半个世纪以来，气象学家和海洋学家一直关注着海洋对于气候变化的作用。然而，要找到一条研究海洋对于气候影响的成功之路并不是一件易事。本文将综述海气边界层观测研究以及海气相互作用对气候影响研究的进展。     

Distribution of large volume image data using the mixed mode of Java Servlet and COM on Web

This paper reports some researches on distribution of large volume image data using techniques of the Mixed Mode of Java Servlet and COM on Web. The architecture and key technologies are discussed in detail. The web distribution system of image is implemented and the system is tested by the application instances. At last, the advantages and disadvantages for this web image distribution mode are analyzed.     

乌东德水电站水垫塘边坡雾化雨入渗数值分析

高坝泄洪雾化雨入渗是影响其水垫塘边坡稳定的关键因素之一。为分析乌东德水电站水垫塘边坡受泄洪雾化雨影响程度,选取水垫塘边坡典型断面,建立二维非饱和、非稳定渗流计算模型,采用有限元法模拟泄洪雾化雨入渗过程,分析雾化雨入渗条件下坡体饱和区范围及压力水头的变化规律,同时对比研究坡面防护措施的效果。结果表明,对于坡体内部渗透性上强、下弱的部位,随着入渗补给量的持续增加,在阻水部位压力水头会逐渐升高;当坡面采取弱透水材料防护后,可显著减少坡面雾雨入渗量,从而显著降低雾化雨入渗对坡体渗流场的影响     

北半球千年温度集成重建所使用的代用序列述评——以石笋为例

充分掌握过去全球气候变化的规律,是分析现在全球气候变化的关键。为了重建近2 000 a的全球（主要是北半球）的温度时空格局,Mann使用了1 209条代用序列。主要评价Mann等在重建中世纪暖期以来（公元800年以来）全球（主要是北半球）的温度时空格局时,所使用的46条代用序列中的8条石笋序列。其中北半球的序列（6条）要多于南半球的序列（2条）。通过对所选石笋序列的文献检索和科学评估,认为Mann等最初选用的8条石笋序列和筛选后剩余的6条石笋序列并非都代表温度信号,其中只有两条序列是原作者认为代表温度信号的,代表降水量信号的序列要多于代表温度信号的序列。所以Mann等选用这些序列重建温度有待商榷。由于石笋代用指标本身的复杂性,其气候指示意义仍然存在争议。     

The role of morphology on the displacement of particles in a step–pool river system

Although studies of sediment transport in steep and coarse-grained channels have been more numerous in recent years, the dynamics of sediment transport in step–pool river systems remain poorly understood. This paper investigates displacements of individual clasts through Spruce Creek (Québec, Canada), a classic step–pool channel, and the effects of the channel morphology on the path length of the clasts. Passive integrated transponder tags (PIT) were used to track the displacement of 196 individual particles over a range of discharges including the bankfull stage. Clasts were tracked after five sequences of flood events. The results showed that the distance distributions match a two-parameter Gamma model. Equal mobility transport occurs for the particle size investigated during each sequence of flood events. Mean travel distance of the clasts can be estimated from excess stream power, and the mobility of the clasts is more than an order of magnitude less than the model reported in riffle–pool channels. The dominant morphological length scale of the bed also controls the path length of the clasts. These results confirm some preliminary observations on sediment transport in step–pool channels.     

Growth,diet, movement,and abundance of adult banded kokopu (Galaxias fasciatus) in five Coromandel,New Zealand streams

Banded kokopu populations were surveyed seasonally over 1 year in five Coromandel streams to determine the influence of food supply on diet, growth, abundance, and movement. Streams with high benthic invertebrate abundance and drift of aquatic origin had high fish abundance. However, terrestrial drift was the dominant food for adult banded kokopu over all seasons and streams, on average comprising 75% of their diet by number and 89% by weight. Annual growth rates of tagged individuals ranged from 3 mm to 16.5 mm, with smaller fish growing faster than large fish. Low growth rates of large fish were consistent with the recapture of a fish that had only grown from 195 mm to 215 mm in 7 years. Our observations confirmed the strong association between banded kokopu, pool habitat, and cover, and also indicated that high fish abundance restricted growth rates and movement and increased interaction.     

Detecting temporal trends and environmentally-driven changes in the spatial distribution of bottom fishes and crabs on the eastern Bering Sea shelf

This study uses a 30-year time series of standardized bottom trawl survey data (1982–2011) from the eastern Bering Sea shelf to model patterns of summer spatial distribution for various bottom fishes and crabs in response to changes in the areal extent of the cold pool, time lag between surveys, and fluctuations in population abundance. This investigation is the first to include data for the 2006–2010 cold period and to use between-year comparisons of local and shelf-wide spatial indices to test specific responses to three different isothermal boundaries within the cold pool. Distributional shifts in population varied considerably among species and directional vectors for some species were greater in magnitude to the east or west than to the north or south; however, in general, eastern Bering Sea shelf populations shifted southward in response to the increasing cold pool size, and after accounting for differences in temperature and population abundance, there was still a temporal northward shift in populations over the last three decades despite the recent cooling trend. Model results for local and shelf-wide indices showed that survey time lag and cold pool extent had a greater effect on spatial distribution than population abundance, suggesting that density-independent mechanisms play a major role in shaping distribution patterns on the eastern Bering Sea shelf. The area enclosed by the 1 °C isotherm most commonly affects both local and shelf-wide spatial indices suggesting that 1 °C is a more important boundary for describing temperature preferences of eastern Bering Sea bottom fishes and crabs than is the 2 °C isotherm used for designating the physical boundary for the cold pool.     

Temperature evolution from the <Emphasis Type="Italic">δ</Emphasis><Superscript>18</Superscript>O record of Hani peat,Northeast China,in the last 14000 years

From the last deglaciation to the Holocene, the Greenland Ice Core (GISP2) δ ¹⁸O records as well as the records of ice-rafted debris on the surface of the North Atlantic have revealed a succession of sudden cooling events on the centennial to millennial scales. However, the temperature proxy records are rarely studied systematically and directly to ensure that this air temperature cooling pattern simultaneously existed in the East Asian Region, in addition to the repeated pattern occurring in the Greater Atlantic Region. A peat cellulose δ ¹⁸O temperature proxy record proximately existing for 14000 years was picked up from the Hani peat in Jilin Province, China. It suggests by comparison that the sudden cooling events, such as the Older Dryas, Inter-Allerød, Younger Dryas, and nine ice-rafted debris events of the North Atlantic, are almost entirely reiterated in the temperature signals of Hani peat cellulose δ ¹⁸O. These cooling events show that the repeatedly occurring temperature cooling pattern not only appeared in the North Atlantic Region in the high latitudes, but also in the Northwest Pacific Region in the middle latitudes. The climate change events marking the start of the Holocene Epoch, the Holocene Megathermal, the “8.2 kyr” event, the “4.2 kyr” event, the Medieval Warm Period, and the Little Ice Age are further discussed. The sensitivity response of Hani peat cellulose δ ¹⁸O to the land surface temperature and the reason for the age accuracy of peat cellulose ¹⁴C are also discussed based on the characteristics of the peat bog environment.     

Annual and interannual variations of the Western Pacific Warm Pool volume and sources of warm water revealed by Argo data

Based on gridded Argo profile data from January 2004 to December 2010, together with the P-vector inverse method, the three-dimensional structure, annual and inter-annual variations in volume of the Western Pacific Warm Pool(WPWP) are studied. The variations of latitudinal and longitudinal warm water flowing into and out of the WPWP and the probable mechanism of warm water maintenance are also discussed. From the surface to the bottom, climatic WPWP tilts southward and its area decreases. The maximum depth could extend to 120 m, such that its volume could attain 1.86×1015 m3. Annual variation of the WPWP volume shows two obvious peaks that occur in June and October, whereas its inter-annual variations are related to ENSO events. Based on a climatic perspective, the warm water flowing latitudinally into the pool is about 52 Sv, which is mainly through upper layers and via the eastern boundary. Latitudinally, warm water flowing outward is about 49 Sv, and this is mainly through lower layers and via the western boundary. In contrast, along the latitude, warm water flowing into and out of the pool is about 28 Sv and 23 Sv, respectively. Annual and inter-annual variations of the net transportation of the warm water demonstrate that the WPWP mainly loses warm water in the west-east direction, whereas it receives warm water from the north-south direction. The annual variation of the volume of WPWP is highly related to the annual variation of the net warm water transportation, however, they are not closely related on inter-annual time scale. On the inter-annual time scale, influences of ENSO events on the net warm water transportation in the north-south direction are much more than that in the west-east direction. Although there are some limitations and simplifications when using the P-vector method, it could still help improve our understanding of the WPWP, especially regarding the sources of the warm water.     

艾比湖二千余年来环境演变的地球化学记录

通过对新疆艾比湖Ash孔二千余年以来沉积的总有机碳含量及其碳同位素、碳酸盐含量及Mg／Ca比值等环境指标综合分析,数据显示：约在公元前500-400年,艾比湖水体面积较小,对应的气候偏干。约公元前400～公元1400年,水体面积较大,处于高水位时期,气候较为湿润,但此时期内的气候也有小幅的冷暖和干湿变化。其中在公元800-1300年期间艾比湖沉积记录显示水生生物对沉积有机质的贡献达到最大,而陆源有机质输入不明显,表明此时湖水水位可能达到二千余年来的最高,这一时段基本对应于中世纪暖期。从碳酸盐含量及Mg/Ca比值指标来看,该地区中世纪暖期可能有一个干湿的波动。公元1400年以来,艾比湖水位下降,其中在15世纪中和19世纪初是两次较为干燥的时期,与其他地区的小冰期气候相对应。