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Microphysical characteristics of precipitating cumulus cloud based on airborne Ka-band cloud radar and droplet measurements 
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下载免费PDF全文 Lei Wei Mengyu Huang Rong Zhang Yuhuan Lü Tuanjie Hou Hengchi Lei Delong Zhao Wei Zhou Yuan Fu 《大气和海洋科学快报》2022,15(2):65-70
在积云中,大多数云粒子的直径在7到10微米之间,而在层云中,大多数云粒子的直径不超过2微米.云滴有效半径与云中行星边界层(PBL)及PBL上层的气溶胶数浓度(Na)呈负相关.在1500米以上的高液态水含量区域,云滴浓度(Nc)变化不大,Na含量降低.高雷达反射率对应于大的FCDP云粒子浓度和小的气溶胶粒子浓度.积云中的... 相似文献
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Ziqiang Duan Huiwang Gao Zengxiang Gao Renlei Wang Yuhuan Xue Xiaohong Yao 《Boundary-Layer Meteorology》2013,148(1):227-239
The air–sea $\text{ CO }_{2}$ flux was measured from a research vessel in the North Yellow Sea in October 2007 using an open-path eddy-covariance technique. In 11 out of 64 samples, the normalized spectra of scalars ( $\text{ CO }_{2}$ , water vapour, and temperature) showed similarities. However, in the remaining samples, the normalized $\text{ CO }_{2}$ spectra were observed to be greater than those of water vapour and temperature at low frequencies. In this paper, the noise due to cross-sensitivity was identified through a combination of intercomparisons among the normalized spectra of three scalars and additional analyses. Upon examination, the cross-sensitivity noise appeared to be mainly present at frequencies ${<}0.8\,\text{ Hz }$ . Our analysis also suggested that the high-frequency fluctuations of $\text{ CO }_{2}$ concentration (frequency ${>}0.8\,\text{ Hz }$ ) was probably less affected by the cross-sensitivity. To circumvent the cross-sensitivity issue, the cospectrum in the high-frequency range 0.8–1.5 Hz, instead of the whole range, was used to estimate the $\text{ CO }_{2}$ flux by taking the contribution of the high frequency to the $\text{ CO }_{2}$ flux to be the same as the contribution to the water vapour flux. The estimated air–sea $\text{ CO }_{2}$ flux in the North Yellow Sea was $-0.039\,\pm \,0.048\,\text{ mg } \text{ m }^{-2}\,\text{ s }^{-1},$ a value comparable to the estimates using the inertial dissipation method and Edson’s method (Edson et al., J Geophys Res 116:C00F10, 2011). 相似文献
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Yixin Yan Chengjun Sun Yuhuan Huang Wei Cao Fenghua Jiang Guipeng Yang Haibing Ding 《中国海洋湖沼学报》2020,38(3):634-649
In this study, cored sediment samples collected by the Jiaolong Submersible at 6 779 m depth from the hadal zone of the Yap Trench in May 2016 were sliced in 1-cm interval from top to bottom, and lipids in each sediment layer were quantitatively and qualitatively analyzed. The vertical distribution profiles of the lipids in the sediment sample, their main existing forms, and their possible sources were investigated. The results show that the concentration of lipid in the surface sediment was the highest with the carbon number from 12 to 27, dominated by medium and short-chain lipids. The total concentration of fatty acids in surface sediment was much higher than those in the offshore and deep-sea areas, being up to 325.77 μg/g due to the funnel effect caused by the “V” terrain of the trench. Fatty acid 18.0 was the most abundant lipids in the sediment sample. Abnormal high concentrations of fatty acid 18.ω7 and alkanes indicated the existence of hydrothermal fluids in the study area. In addition, saturated fatty acids and monounsaturated fatty acids existed mainly in free form, and polyunsaturated fatty acids existed mainly in bound form. Most of the alkanes were in bound form, and their major source was autochthounous input. The carbon number of alcohols in the sediment sample ranged from 12 to 20, mainly existed in bound form. The source of fatty acids was mainly autochthonous input, and the neutral lipids had both marine and terrestrial origin. This is the first study of lipids in hadal sediment of the Yap Trench. The results will promote deeper understanding of organic carbon cycle in marine environment. 相似文献
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Huaming Yu Lu Wang Liang Kuang Haiqing Yu Yuchen Sun Yuhuan Qu Xin Wu 《中国海洋大学学报(英文版)》2016,15(2):209-218
Based on the finite-volume coastal ocean model(FVCOM),a three-dimensional numerical model FVCOM was built to simulate the ocean dynamics in pre-dam and post-dam conditions in Bachimen(BCM).The domain decomposition method,which is effective in describing the conservation of volume and non-conservation of mechanical energy in the utilization of tidal energy,was employed to estimate the theoretical tidal energy resources and developable energy resources,and to analyze the hydrodynamic effect of the tidal power station.This innovative approach has the advantage of linking physical oceanography with engineering problems.The results indicate that the theoretical annual tidal energy resources is about 2×10~8 k Wh under the influence of tidal power station;Optimized power installation is confirmed according to power generation curve from numerical analysis;the developable resources is about 38.2% of theoretical tidal energy resources with the employment of one-way electricity generation.The electricity generation time and power are 3479 hours and 2.55×10~4 KW,respectively.The power station has no effect on the tide pattern which is semi-diurnal tide in both two conditions,but the amplitudes of main constituents apparently decrease in the area near the dam,with the M_2 decreasing the most,about 62.92 cm.The tidal prism shrinks to 2.28×10~7 m~3,but can still meet the flow requirement for tidal power generation.The existence of station increases the flow rate along the waterway and enhances the residual current.There are two opposite vortexes formed on the east side beside the dam of the station,which leads to pollutants gathering. 相似文献
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利用2012年6月29日的通辽和白城飞机联合探测资料(包括DMT和PMS)及雷达资料,对吉林省一次层状云降水消散期微观物理结构特征进行分析研究。结果表明:该天气过程是在东北锋面气旋影响下发展起来的,给东北地区带来大范围降水,属于吉林地区春季常见的降水性层状云系As-Ac-Ns云型。Ns云底约在1000m左右,云顶不超过4000m,Ns云层较厚,在该云系发展过程中雨层云下伴有碎雨云。结合DMT和PMS,小粒子在每个高度层上都占主要部分,0.61～2μm的小粒子浓度可达100cm-3,直径大于2μm的粒子谱型基本都是单调递减型;云内含水量较少,极大值也不足0.01g·m-3;粒子有效直径随高度变化呈多峰分布,粒子有效直径与粒子浓度在0℃层以下范围内,大的粒子有效直径对应小的粒子浓度,随着高度的升高粒子有效直径呈递减趋势。 相似文献
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屈产河流域位于黄土高原东部,流域内植被稀疏,土层厚而松,降水少且集中,遇暴雨天气容易发生泥石流、山洪等灾害。本文基于2020年8月5~6日罕见强降水的实地灾情调查结果,对FloodArea模型在屈产河流域的淹没水深和风险评估结果进行检验。结果表明:屈产河流域地势低洼的河道附近及干沟地区山洪风险较大;此次强降水过程屈产河流域最大淹没深度2.8 m,受洪灾影响人口为5475人,受影响GDP为3615×10^(4)元,耕地和居民地受灾面积分别为20.7 km^(2)和0.7 km^(2)。模拟最大淹没深度、受影响GDP和受灾面积与实际调查情况基本一致,但受影响人口低于实际调查结果,该结果表明FloodArea模型在屈产河流域具有较好的洪水淹没模拟效果,可用于暴雨洪涝灾害风险评估与预警业务。 相似文献
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中国沿海地质环境与区域持续发展的若干问题探讨 总被引：2，自引：1，他引：2
本文分析了中国沿海岩石圈动力学的基础特征, 指出中国东部沿海地质环境与灾害存在南北分异的格局, 阐述了沿海区域工程地质环境的基本规律, 并通过全球及中国近百年海平面变化, 以及人类工程活动对河口海岸地质环境影响的分析, 对沿海地区未来的地质环境与灾害趋向做了初步评估, 并认为中国沿海21世纪的环境与发展将面临严峻的挑战, 特别是环渤海地区。最后, 对影响沿海区域发展的若干问题进行了初步探讨并提出了几点建议。 相似文献