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1.
通过对影响广西气象局计算机中心机房环境温度的因素的分析,提出解决环境温度过高的具体办法。  相似文献   

2.
根据广西区气象局中心计算机房环境温度要求,简述计算机房空调设备设计施工,对计算机机房环境温度运行保障有一定指导作用.  相似文献   

3.
环境温度场对台风等扰动发展和移动的影响   总被引:4,自引:0,他引:4  
刘辉  董克勤 《气象学报》1987,45(2):188-194
本文应用一个CISK机制的扰动模式,从理论上分析了环境温度梯度场对台风等对流性扰动发展和移动的影响。结果表明,环境温度梯度对台风等扰动的发展可产生明显的影响,而且该影响与环境温度梯度的方向及该梯度场和台风间的相对位置有很大关系,另外,环境温度梯度可使扰动出现一相当强的趋暖运动。本文的结果可为冷空气对台风发展和移动的影响提供一些动力方面的解释,对于实际的台风预报,有一定的参考价值,对于了解斜压环境中的对流系统的发展机制和参数化,本文的结果也有一定意义。  相似文献   

4.
温控风杯防冻仪的研制   总被引:1,自引:0,他引:1  
针对我国部分地区地面气象自动站风速传感器在冬天常被冻死现象,研制了温控风杯防冻仪。仪器主要由加热装置和控制装置(人工控制和自动控制)组成。系统在自动控制状态时,加热器的工作状态根据环境温度的变化而改变,当环境温度低于提前设置的阈值时,加热器开始工作,当环境温度高于阈值时,加热器停止工作。实验结果和实际应用的效果都表明,仪器具有很好的实用性和稳定性。  相似文献   

5.

针对我国部分地区地面气象自动站风速传感器在冬天常被冻死现象,研制了温控风杯防冻仪。仪器主要由加热装置和控制装置(人工控制和自动控制)组成。系统在自动控制状态时,加热器的工作状态根据环境温度的变化而改变,当环境温度低于提前设置的阈值时,加热器开始工作,当环境温度高于阈值时,加热器停止工作。实验结果和实际应用的效果都表明,仪器具有很好的实用性和稳定性。

  相似文献   

6.
杨成彬  郑祖光  王雨 《大气科学》1994,18(Z1):810-819
本文采用二维板对称高截断谱模式研究了环境温度场和偶度场对台风发生、发展的影响,指出整层平均的环境温度场的水平梯度和涡度场是影响台风重要因子。较强的环境温度汤梯度的作用类似于水平方向不均匀加热场的作用,能造成暖区上升、冷区下沉的热力直接环流,并且温度场的梯度越大,环流越强。对于整层平均的绝对涡度场而言,只有弱的正的平均绝对涡度才有利于台风的维持。  相似文献   

7.
HMP45D湿度传感器温度特性测试与分析   总被引:1,自引:1,他引:0  
付锡桂  朱乐坤 《气象科技》2009,37(5):584-586
HMP45D型温湿一体化传感器,在我国气象部门被广泛用于测量空气湿度。由于我国地域辽阔,南方和北方气象台站环境温度差异较大,尤其是在寒冷的冬季,地处北部地区的台站,环境温度可达-40℃以下。为掌握环境温度的变化对湿度测量准确度的影响,本次试验随机选取3支HMP45D湿度传感器作为被测件,利用双压法湿度发生器发生的湿度值作为标准值,在不同温度点上,对3支湿度传感器进行了测量准确度的温度影响量测试。  相似文献   

8.
黄晓因  徐丽芬 《气象科技》2005,33(4):367-369372
对干湿球系数A与环境温度t的关系进行了研究。结果指出,A不仅与风速有关,也与环境温度有关,如果不考虑风速和环境温度,使用干湿球测湿法获得的测量结果没有使用价值。t〉40℃以后,随着t的升高,使用A的拟合公式计算得到的相对湿度值其误差愈来愈大,在相对湿度较低时情况更为明显。为此提出了在40℃〈t〈80℃范围内A的计算公式。经验证,使用此计算公式获得A值后再计算出相对湿度,其误差小于1.4%。  相似文献   

9.
名词解释     
《气象》1975,1(4):10-10
沙氏指数 沙瓦特指数简称沙氏指数,也叫做稳定指数,通常是用来判断大气稳定度的一种判据。将850毫巴上的空气质点沿干绝热线上升到凝结高度后,再沿湿绝热线上升到500毫巴,以500毫巴上的环境温度减去该上升点的温度,所得的差数为沙氏指数。如指数<0,表示上升空气质点的温度高于环境温度,大气不稳定,负值越大,不稳定程度也越大;如指数>0,表示上升空气质点的温度低于环境温度,大气稳定,正值越大,稳定程度也越大。  相似文献   

10.
辐射增温效应对水稻叶片温度及光合速率的影响   总被引:1,自引:1,他引:1       下载免费PDF全文
根据人工气候箱试验资料,分析了水稻叶片温度随环境温度、辐射强度的变化规律及辐射增温效应对单叶光—光合曲线的影响;由直角双曲型光合模型模拟了辐射增温效应对叶片光合特征的影响。结果表明,环境温度低于光合的生理适宜温度时,辐射增温效应将使叶片温度升高,从而有利于光合能力的提高;反之则相反。  相似文献   

11.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

12.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

13.
High-resolution numerical simulation data of a rainstorm triggering debris flow in Sichuan Province of China simulated by the Weather Research and Forecasting (WRF) Model were used to study the dominant cloud microphysical processes of the torrential rainfall. The results showed that: (1) In the strong precipitation period, particle sizes of all hydrometeors increased, and mean-mass diameters of graupel increased the most significantly, as compared with those in the weak precipitation period; (2) The terminal velocity of raindrops was the strongest among all hydrometeors, followed by graupel’s, which was much smaller than that of raindrops. Differences between various hydrometeors’ terminal velocities in the strong precipitation period were larger than those in the weak precipitation period, which favored relative motion, collection interaction and transformation between the particles. Absolute terminal velocity values of raindrops and graupel were significantly greater than those of air upward velocity, and the stronger the precipitation was, the greater the differences between them were; (3) The orders of magnitudes of the various hydrometeors’ sources and sinks in the strong precipitation period were larger than those in the weak precipitation period, causing a difference in the intensity of precipitation. Water vapor, cloud water, raindrops, graupel and their exchange processes played a major role in the production of the torrential rainfall, and there were two main processes via which raindrops were generated: abundant water vapor condensed into cloud water and, on the one hand, accretion of cloud water by rain water formed rain water, while on the other hand, accretion of cloud water by graupel formed graupel, and then the melting of graupel formed rain water.  相似文献   

14.
The predictability of the position, spatial coverage and intensity of the East Asian subtropical westerly jet(EASWJ) in the summers of 2010 to 2012 was examined for ensemble prediction systems(EPSs) from four representative TIGGE centers,including the ECMWF, the NCEP, the CMA, and the JMA. Results showed that each EPS predicted all EASWJ properties well, while the levels of skill of all EPSs declined as the lead time extended. Overall, improvements from the control to the ensemble mean forecasts for predicting the EASWJ were apparent. For the deterministic forecasts of all EPSs, the prediction of the average axis was better than the prediction of the spatial coverage and intensity of the EASWJ. ECMWF performed best, with a lead of approximately 0.5–1 day in predictability over the second-best EPS for all EASWJ properties throughout the forecast range. For probabilistic forecasts, differences in skills among the different EPSs were more evident in the earlier part of the forecast for the EASWJ axis and spatial coverage, while they departed obviously throughout the forecast range for the intensity. ECMWF led JMA by about 0.5–1 day for the EASWJ axis, and by about 1–2 days for the spatial coverage and intensity at almost all lead times. The largest lead of ECMWF over the relatively worse EPSs, such as NCEP and CMA, was approximately 3–4 days for all EASWJ properties. In summary, ECMWF showed the highest level of skill for predicting the EASWJ, followed by JMA.  相似文献   

15.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

16.
冰冻圈变化的适应研究是冰冻圈科学领域的新兴研究方向,是当今自然科学与社会科学交叉融合跨学科集成研究的典型代表。起步于2007年的中国冰冻圈变化适应研究,经历了早期的探索,研究重点由评价脆弱性发展为量化冰冻圈变化的影响,形成以影响/风险—脆弱性—适应全链条的完善的研究体系,研究方法突破传统的指标体系赋权法的不足,初步实现了定量化,有机结合影响/风险、脆弱性、适应三方面的研究结果,使冰冻圈变化的适应措施由偏重宏观性、普适性开始转向更有针对性。未来中国冰冻圈变化的适应研究应拓展、完善和深化现有的理论体系,构建冰冻圈与社会经济耦合模型,科学量化冰冻圈全要素变化的影响,建立不同利益相关者与科学家共同参与的研究新模式,科学有效应对与适应冰冻圈变化及其影响。  相似文献   

17.
淮河流域水文极值预测模型研究   总被引:1,自引:0,他引:1  
为探索气候变化影响下水文极值的非平稳性和预测方法,建立了水文极值非平稳广义极值(GEV)分布的统计预测模型。利用1952-2010年淮河上游流域累计面雨量和流量年最大值资料、同期500 hPa环流特征量资料以及17个CMIP5模式对环流特征量的模拟结果,筛选出对水文极值影响显著的年平均北半球极涡强度指数作为GEV分布参数的预测因子。分析了在RCP2.6、RCP4.5和RCP8.5情景下2006-2050年淮河上游流域水文极值对气候变化的响应。结果表明,10年以下与10年以上重现期的水文极值在非平稳过程中呈现前者下降而后者上升的相反变化趋势;多模型预测的集合平均在未来情景中均呈现上升趋势,情景排放量越大增幅越大,重现期越长增幅也越大。与极值的常态相比,极值的极端态更易受气候变化影响。  相似文献   

18.
This article analyzes a political process in the aftermath of a disaster and explains why and how it led to maladaptation. Grounding Gramsci’s theory of the State on a case of post-disaster response to a fatal mudslide in the city of Sarno in Italy, this research argues that, under certain conditions, civil society and the ruling classes may coalesce to produce policies that are maladaptive. We unpack the mechanisms through which consent was reproduced in Sarno, and show how the claims of civil society were articulated and fused with the hegemonic goals of capital circulation and economic growth, reaffirming a view of government as only a provider of safety. A Gramscian treatment of the State as a process, and not as a thing, highlights that the main barrier to adaptation is not the lack of techno-managerial solutions. It is the lack of political struggle around the social reconfiguration of the logic and functions of the State.  相似文献   

19.
傅良  罗玲  张玉静  娄小芬  钱浩 《气象科学》2022,42(2):182-192
选取2015—2018年影响华东地区的13个台风个例,分析降水极端天气指数EFI (Extreme Forecast Index)和SOT (Shift of Tails)与台风降水之间的统计关系。结果表明:EFI和SOT与降水气候百分位之间存在明显的正相关关系。EFI和SOT越大,强降水发生概率越高。随着预报时效的增加,EFI和SOT指数对暴雨和大暴雨的预报效果逐渐变差。对于短期(72 h以内的时效),EFI预报技巧优于SOT,而随着预报时效的延长,SOT的预报技巧逐渐接近并超过EFI。以TS评分最大为标准兼顾合理的预报偏差,得到两种极端天气指数不同预报时效、不同等级暴雨的预报阈值。总体而言,事件越极端,EFI和SOT的预报阈值越大,对于暴雨和大暴雨,EFI指数的预报阈值随着预报时效的延长有减小趋势,而SOT的预报阈值基本保持不变。在台风极端降水预报中,EFI和SOT可以作为EC定量降水预报的补充,有助于减少强降水的漏报,并提早发出预警信息。  相似文献   

20.
Recent Advances in Predictability Studies in China (1999-2002)   总被引:10,自引:2,他引:8  
Since the last International Union of Geodesy and Geophysics (IUGG) General Assembly (1999), the predictability studies in China have made further progress during the period of 1999-2002. Firstly, three predictability sub-problems in numerical weather and climate prediction are classified, which are concerned with the maximum predictability time, the maximum prediction error, and the maximum allowable initial error, and then they are reduced into three nonlinear optimization problems. Secondly, the concepts of the nonlinear singular vector (NSV) and conditional nonlinear optimal perturbation (CNOP) are proposed,which have been utilized to study the predictability of numerical weather and climate prediction. The results suggest that the nonlinear characteristics of the motions of atmosphere and oceans can be revealedby NSV and CNOP. Thirdly, attention has also been paid to the relations between the predictability and spatial-temporal scale, and between the model predictability and the machine precision, of which the investigations disclose the importance of the spatial-temporal scale and machine precision in the study of predictability. Also the cell-to-cell mapping is adopted to analyze globally the predictability of climate,which could provide a new subject to the research workers. Furthermore, the predictability of the summer rainfall in China is investigated by using the method of correlation coefficients. The results demonstrate that the predictability of summer rainfall is different in different areas of China. Analysis of variance, which is one of the statistical methods applicable to the study of predictability, is also used to study the potential predictability of monthly mean temperature in China, of which the conclusion is that the monthly mean temperature over China is potentially predictable at a statistical significance level of 0.10. In addition,in the analysis of the predictability of the T106 objective analysis/forecasting field, the variance and the correlation coefficient are calculated to explore the distribution characteristics of the mean-square errors.Finally, the predictability of short-term climate prediction is investigated by using statistical methods or numerical simulation methods. It is demonstrated that the predictability of short-term climate in China depends not only on the region of China being investigated, but also on the time scale and the atmospheric internal dynamical process.  相似文献   

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