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Zenghong Liu Xiaogang Xing Zhaohui Chen Shaolei Lu Xiaofen Wu Hong Li Chunling Zhang Lijing Cheng Zhaoqin Li Chaohui Sun Jianping Xu Dake Chen Fei Chai 《海洋学报(英文版)》2023,42(2):1-2
The international Argo program, a global observational array of nearly 4 000 autonomous profiling floats initiated in the late 1990s, which measures the water temperature and salinity of the upper 2 000 m of the global ocean, has revolutionized oceanography. It has been recognized one of the most successful ocean observation systems in the world. Today, the proposed decade action “OneArgo” for building an integrated global, full-depth, and multidisciplinary ocean observing array for beyond 2020 ... 相似文献
483.
Changes in reference evapotranspiration over China during 1960–2012: Attributions and relationships with atmospheric circulation 下载免费PDF全文
This study investigates reference evapotranspiration (ET0) trends in China from 1960 to 2012 based on the Penman–Monteith equation and gridded meteorological measurements. Under the combined impacts of factors influencing ET0 (i.e., net radiation [RN], mean temperature [TAVE], vapour pressure deficit [VPD], and wind speed [WND]), both seasonal and annual ET0 for the whole China and more than half of the grids decreased over the past 53 years. The attribution analyses suggest that for the whole China, the WND is responsible for annual and seasonal ET0 decreases (excluding summer, where RN is responsible). Across China, the annual cause of WND with the largest spatial extent (43.1% of grids) mainly derives from north of the Changjiang River Basin (CJRB), whereas VPD (RN) as a cause is dispersedly distributed (within and to the south of the CJRB). In summer, RN is dominant in more than half of the grids, but the dominance of VPD and WND accounts for approximately 90% of grids during the remaining seasons. Finally, the correlation coefficients between ET0 and the Atlantic Oscillation (AO), North AO, Indian Ocean Dipole (IOD), Pacific Decadal Oscillation (PDO), and El Niño Southern Oscillation (ENSO) indices with different lead times are calculated. For the whole China, annual and seasonal ET0 always significantly correlate with these indices (excluding the IOD) but with varied lead times. Additionally, near half of the grids show significant and maximum (i.e., the largest one between ET0 and a certain index with a lead time of 0–3 seasons) correlation coefficients of ET0 with PDO in spring and summer, ENSO in autumn, and AO in winter. This study is not only significant for understanding ET0 changes, but it also provides preliminary and fundamental reference information for ET0 prediction. 相似文献
484.
为探究长江中下游富营养化浅水湖泊的浮游植物初级生产力季节性演替特征及其驱动因子,本研究于2020年4月(春)、8月(夏)、10月(秋)及2021年1月(冬)对湖北长湖浮游植物进行采样调查,同时运用黑白瓶测氧法及VGPM模型估算法分别估算了其浮游植物生产力水平,并探究驱动初级生产力季节性变化的主要环境因子。结果显示,4个季节共鉴定出浮游植物194种,其中绿藻门(95种,49%)和硅藻门(40种,21%)居绝对优势地位;黑白瓶法测得浮游植物水柱总生产力(Pt)季节变化为:夏季((1841.24±345.93) mg C/(m2·d))>秋季((1324.14±208.34) mg C/(m2·d))>春季((847.50±247.72) mg C/(m2·d))>冬季((711.43±133.52) mg C/(m2·d)),其中M2站位在夏季采样时(2424.66 mg C/(m2·d))水柱总生产力最高;在垂直空间上,浮游植物总生产力(G... 相似文献
485.
基于器件模拟仿真,设计了一种1.5 μm波长InGaAsP-InP晶体管激光器材料外延结构. 其多量子阱有源区置于基区非对称波导中. 仿真结果显示该外延结构能够获得较好的光场限制和侧向电流限制. 对该材料MOCVD生长研究表明,基极重掺杂接触层中Zn2+扩散将导致量子阱严重退化. 通过对其扩散过程的模拟仿真,采用平均掺杂浓度为1×1018 cm-3的梯度掺杂,有效地抑制了Zn2+向量子阱区的扩散. 所获得的外延材料在 相似文献
486.
GPS Solutions - High-frequency global navigation satellite system (GNSS) observations are of great significance for structural health monitoring. At present, most studies on high-frequency GNSS... 相似文献
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