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991.
Kristina B. Katsaros Paris W. Vachon W. Timothy Liu Peter G. Black 《Journal of Oceanography》2002,58(1):137-151
This article reviews several microwave instruments employed in research and analysis of tropical cyclones (TCs), typhoons,
and hurricanes. The instruments discussed include scatterometers, microwave radiometers, synthetic aperture radars (SARs),
and rain radar from space. Examples of the particular contribution by one or more of these instruments in analysis of several
storms illustrate the comprehensive new views provided by the SeaWinds scatterometers, the detailed high-resolution wind field
provided by RADARSAT-1 SAR, particularly inside and in the vicinity of hurricane “eyes,” and the presence of secondary flows
in the region between rainbands in TCs. The high spatial resolution of precipitation data from the Tropical Rainfall Measuring
Mission's rain radar, combined with scatterometer or SAR data, give a significant improvement in the details that can be seen
from space, at the surface, and in the precipitating areas of TCs. The microwave instruments provide a penetrating view below
the upper level cirrus clouds.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
992.
993.
使用透射电镜和萤光抗体染色,对处于可培养和活的非可培养状态的霍乱弧菌进行了细胞形态结构比较研究。结果表明:处于非可培养状态的霍乱菌细胞,体积明显地缩小,形态由弧形变成了球形,我们共观察了382个非可培养状态的细胞,发现它们的细胞壁都是完整的,即不是细菌-L型,在这些细胞中也都没发现芽孢结构 相似文献
994.
泥蚶及菲律宾蛤仔对环境中氨的耐受力 总被引:1,自引:0,他引:1
本文对泥蚶成贝、幼贝,菲律宾蛤仔成贝、幼贝的未离解氨氮 168h LCD_(50),EC_(50)(降低耐低氧环境能力50%的浓度)进行了试验,并对氨的致死和亚致死浓度与内湾养虾水域(乳山东湾)、试验虾池及利用虾池水的试验贝池底质环境的氨氮水平作了概略评价。 相似文献
995.
微波辐射计遥感海水盐度的水池实验研究 总被引:1,自引:0,他引:1
通过水池实验研究了L波段微波辐射和盐度的关系,并进行了盐度的反演计算。实验中,先向水池内加入天然海水,然后通过向水池中添加自来水的方式调节降低池内水体的盐度,使盐度从31.67逐步降低到27.48。在此期间,利用微波辐射计观测池内水体的L波段H极化和V极化辐射值以及S波段V极化辐射值,利用CTD观测池内水体的温度和盐度。L波段微波辐射值和根据辐射理论计算出的亮温值具有很好的线性关系。利用最大和最小的2个盐度下的微波辐射值和由辐射理论计算的亮温得到定标公式,将观测的辐射值换算为亮温。最后利用半解析的反演算法反演盐度。本次实验的反演最大误差为2.1,均方差为0.3。 相似文献
996.
HF radar detection of tsunamis 总被引:1,自引:0,他引:1
Belinda J. Lipa Donald E. Barrick John Bourg Bruce B. Nyden 《Journal of Oceanography》2006,62(5):705-716
This paper demonstrates that HF radar systems can be used to detect tsunamis well before their arrival at a coastline. We
solve the equations of motion and continuity on the ocean surface using models to simulate the signals produced by a tsunami
approaching the east U.S. coast. Height and velocity profiles are derived along with expressions for the radar-observed current
velocities in terms of bathymetry and tsunami height and period. Simulated tsunami-generated radial current velocities are
superimposed on typical maps of radial velocity generated by a Rutgers University HF radar system. A detection parameter is
defined and plotted to quantify the progress of the tsunami, which is shown to be detectable well before its arrival at the
coast. We describe observations/warnings that would have been provided by HF radar systems at locations in the path of the
2004 Indian Ocean tsunami. 相似文献
997.
Abstract. Combined effects of temperature, salinity, and metal enrichment (Zn, Mn, Co) on the growth rate and chemical composition of Fucus vesiculosus L. were studied in culture. Factorial combinations of two temperatures and three salinities were used. The results indicated that the accumulation of Zn and Mn into algal tissue was enhanced by dilution of the media, whereas Co accumulation exhibited maxima at the medium salinity. Zn accumulation was enhanced by temperature, while the opposite was true for Mn and Co.
In the presence of metals the usual dilution-induced changes in growth activity and chemical composition of Fucus plants were altered, while responses to the temperature factor remained unchanged. In diluted media, growth activity and mannitol content decreased along with a simultaneous increase of protein content. In the presence of Zn and Mn the mannitol content exhibited peaks at the medium salinity; in the presence of Co the dilution-induced pattern remained unchanged. Salinity-induced changes in growth and protein content were altered in the presence of metals. Maxima in growth rates were found at the medium salinity. Growth was higher in extremely diluted media than in scawater, indicating an inversion of responses to the salinity factor. Both the growth rate and mannitol content were lowest under the influence of Zn. 相似文献
In the presence of metals the usual dilution-induced changes in growth activity and chemical composition of Fucus plants were altered, while responses to the temperature factor remained unchanged. In diluted media, growth activity and mannitol content decreased along with a simultaneous increase of protein content. In the presence of Zn and Mn the mannitol content exhibited peaks at the medium salinity; in the presence of Co the dilution-induced pattern remained unchanged. Salinity-induced changes in growth and protein content were altered in the presence of metals. Maxima in growth rates were found at the medium salinity. Growth was higher in extremely diluted media than in scawater, indicating an inversion of responses to the salinity factor. Both the growth rate and mannitol content were lowest under the influence of Zn. 相似文献
998.
高频地波雷达反演海浪的海上对比验证方法研究 总被引:1,自引:0,他引:1
在介绍高频地波雷达反演海浪要素工作原理的基础上 ,利用 2 0 0 0年 10月在浙江舟山海域进行的 OSMAR2 0 0 0和 SZF1- 海上对比验证实验中所获取的资料进行系统比较分析 ,验证了OSMAR2 0 0 0探测海洋海浪要素的精度 ,并分析了 OSMAR2 0 0 0反演海浪时的误差成因 相似文献
999.
1000.
海面粗糙度对于海洋工程和海洋军事都非常重要,但对海面粗糙度的现场观测资料非常少, 这大大制约了对海面粗糙度的认识。利用 TOPEX 高度计风速资料实现了对海面粗糙度的反演,并利用 1993 年和1998 年两年的资料对西北太平洋海域的海面粗糙度进行了研究。 相似文献