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991.
992.
In this paper, the decade data of meteorological satellite and surface meteorological observation of China have been analysed.
The relationship between cloud and radiation has been studied. A set of empirical formulae of the ralationships between the
albedo and cloud amount, the outgoing longwave radiation and cloud amount in Chinese different districts and different seasons
has been deduced. They express simply the response of both planet reflectivity and earth-atmosphere outgoing longwave radiation
to the change of cloud amount. So that the sensitivity of net radiation of the earth-atmosphere system to the change of cloud
amount and the ratio of cloud reflective effect to greenhouse effect can be estimated. In this paper, the radiative process
of the earth-atmosphere system, cloud and radiative balance and its effect on climate have been synthetically studied.
1The project is supported by National Natural Sciences Fundation of China (NNSFC). 相似文献
993.
994.
995.
This paper presents 210 positions of Phoebe, the ninth satellite of Saturn, observed with the 1-m telescope at the Yunnan Observatory during the years 2003–2005, using a CCD image-overlapping calibration method proposed recently by Peng et al. After the observed positions of Phoebe are compared with its theoretical positions computed by the new JPL ephemerides DE405 and SAT199, the mean residuals (observed minus computed) are 0.21 and −0.05 arcsec in right ascension and declination, respectively, with a standard deviation of 0.06 arcsec. 相似文献
996.
997.
The ecological environment in the East China Sea (ECS) and the Yellow Sea (YS) has changed significantly due to sea-level rising and the Kuroshio incursion since the last deglaciation. In this study, biomarker records of core F10B from the mud area southwest off Cheju Island (MSWCI) were generated to evaluate phytoplankton productivity and community structure changes in response to environmental evolution during the last 14 kyr. The contents of diatom, dinoflagellate and haptophyte biomarkers (brassicasterol, dinosterol and C37 alkenones) display similar trends, with increasing phytoplankton productivity during the last 14 kyr due to the increased influences of the Kuroshio, and especially due to the eddy-induced upwelling during the late Holocene. On the other hand, the contents of terrestrial biomarkers (C28 +C30 +C32 n-alkanols) and terrestrial organic matter (TOM) proxies (TMBR’ and BIT) all reveal decreasing TOM input into the area around the sampling site for the 14 kyr, mostly due to sea-level rising. Phytoplankton biomarker ratios reveal a shift from a haptophyte-dominated community at 6.2–2.5 kyr BP to a diatom-dominated community at 2.5–1.45 kyr BP, likely caused by a stronger cold eddy circulation system at 2.5–1.45 kyr BP in the MSWCI. 相似文献
998.
Characteristics of Spatial and Temporal Variations of Monthly Mean Surface Air Temperature over Qinghai-Tibet Plateau 总被引:1,自引:0,他引:1
ZHANG Qianggong KANG Shichang YAN Yuping 《中国地理科学(英文版)》2006,16(4):351-358
1 Introduction The Qinghai-Tibet Plateau, known as the highest plateau with the most complex topography in the world, covers an area of more than 200km2, with a mean elevation of more than 4000m a.s.l. (Ye and Gao, 1979). Surrounded by the Earth’s highest mountains, such as the Himalayas, Pamir, Kunlun Mountains, the plateau plays a significant role in climate change in China even in the world, thus attracted great attention of researchers. Up to now, many achievements have been gained by… 相似文献
999.
本文阐述平流层气溶胶的光学常数在不同温度下取值时,用Mie散射理论对不同浓度的平流层气溶胶红外波段的辐射特性进行的计算和分析。分析结果表明:在卫星遥感中,由温度引起的平流层气溶胶光学常数的变化对某些红外波段的平流层气溶胶辐射特性的影响是不容忽视的。 相似文献
1000.
根据创伤弧菌(Vibrio vulnificus)的溶细胞毒素基因序列和哈氏弧菌(Vibrio harveyi)的toxR基因序列,分别设计并合成两对特异性引物,通过PCR反应条件优化,测试两种菌的特异性和敏感性,建立双重PCR方法,同时快速检测V.vulnificus和V.harveyi。结果表明:纯培养V.vulnificus和V.harveyi的检测灵敏度分别是12 cfu/mL和18 cfu/mL,与无乳链球菌、海豚链球菌、副溶血弧菌及美人发光杆菌无交叉反应;此PCR检测方法具有良好的特异性、敏感性,具快速、高效等优点,对细菌V.vulnificus和V.harveyi诊断与防治具有较好的临床应用性。 相似文献