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针对某一个气候要素，将我区100个气象观测站分为若干个气候区，分别对每一个气候区的气候要素和高度、经度、纬度、坡度、坡向5项地理信息要素进行分析，发现其相关关系，建立非线性回归方程，然后在新疆地图上确定一个与行政区划无关的范围，认为该范围内所有网格点上的气候要素与地理信息要素也具有同样的对应关系，进行小网格气候要素推算。 相似文献
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中国南方双季稻播种面积占到全国水稻的85%以上, 研究该区域对气候变化的响应有助于科学地规划和管理双季稻生产。以江南、华南双季稻区为研究对象, 选取1961—2010年南方双季稻区275个数据完整性较好的气象观测站点, 对双季稻区平均气温、日照时数、降水量等气候资源演变规律及其可能变化的分析表明: 该研究区域正处于气温显著上升阶段, 气候倾向率为2℃/(10 a), 尤其是1997年气温突变之后升温幅度进一步增大, 气候倾向率增大为5℃/(10 a), 且秋冬季增温更为显著。研究区域降水年际波动较大, 无明显增减趋势; 从季节上看, 春秋降水有减少趋势, 而冬夏有增加趋势, 且使降水分布更为集中。从空间演变看, 双季稻区气候资源的演变趋势存在较大的差异, 其中华南稻区呈暖湿化, 对喜温好水的双季稻生产是利大于弊; 而江南稻区则呈暖干化趋势, 对水稻生产不利; 同时秋旱风险加大, 尤其是西部地区将面临水资源减少、水稻种植用水不足。另一方面, 随着双季稻区气候变暖, 早稻适宜播种期提前、早晚稻生长季延长, 热量资源增加以及薄膜育秧技术广泛应用等, 都将使双季稻种植格局调整。双季稻区高温日数增多, 早晚稻生长发育无效热量也随之增加, 整体上江南热量资源的有效性低于华南, 尤其是江西和湖南两省, 热量有效性均 < 85%;华南大部地区热量有效性均高于95%。因而, 各地可根据所处区域气候资源要素演变规律及热量有效性分布选取产量与品质更好的中晚熟品种种植, 提高水稻种植积极性, 促进早晚稻安全生产。 相似文献
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本文依据我省气候和耕地不足等实际,对继续实行粮食多熟制的可行性和必要性进行分析。一、我省气候适宜双季稻为主的三熟制我国长江以南到南岭以北一带,盛产水稻,是我国粮食单产最高的地区。浙江位于本区的最东部,具有适宜双季稻为主三熟制生产的气候条件。 相似文献
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利用1971~2000年河南省32个农业气象站逐年气象资料,选取年平均气温、极端最高气温、极端最低气温、无霜期、降水量、相对湿度、蒸发量等7个气候要素,对河南省气候变化总体趋势和8个气候区的气候变化趋势进行分析。结果表明全省总体上每10年:年平均气温上升0.34℃,极端最高气温下降0.25℃,极端最低气温上升0.5℃,无霜期延长3天,年降水量增加5.0 mm,相对湿度增加0.08%,蒸发量减少86.8 mm。总体气候趋向温和、湿润,气候条件趋于改善。8个气候区中,7个气候区总体气候条件趋于暖湿,仅1个气候区总体气候条件趋于暖干。 相似文献
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Wayne M. Angevine Henk Klein Baltink Fred C. Bosveld 《Boundary-Layer Meteorology》2001,101(2):209-227
The morning transition between the stable nocturnal situation and the daytime convective boundary layer (CBL) is of interest both for basic understanding and for initializing prognostic models. While the morning growth phase of the CBL has been studied in detail, relatively little has been published on the transition itself. In this paper, conventional observations of surface temperature, humidity, and turbulent fluxes,and data from a meteorological tower, are combined with measurements of the onset of convection by boundary-layer wind profilers to explore the timing and behaviour of the transition period. The transition is defined here as the period between sunrise and the time at which the depth ofconvection reaches about 200 m AGL. Diagnostic relationships based on surface heat flux, the temperature difference between 2 m and 200 m, and bulk Richardson number are explored. The transition is foundto be enabled by surface heating relaxing the surface stability, while the warming of the layerbetween 2 m and 200 m is in large part due to shear-driven entrainment. 相似文献
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对2004年初期气象短信业务的发展方式和状况,以及2004年后期的发展模式进行了认真的分析,并对2005年气象短信业务的新增长点进行了阐述。认为2005年应进一步扩大发展商,并采取多样化的推广模式,以使订制率从目前的3%～5%提高到10%左右。 相似文献
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The Impact Of Air-Flow Separation On The Drag Of The Sea Surface 总被引：2，自引：1，他引：2
An approach that allows assessment ofthe impact of air-flow separation (AFS) fromwave breaking fronts on the sea-surface drag is presented. Wave breaking fronts are modelled by the discontinuities of the sea-surface slope. It is assumedthat the dynamics of the AFS from wave breaking crests is similar to thatfrom the backward facing step. The form drag supported by an individualbreaker is described by the action of the pressure drop distributed alongthe forward face of the breaking front. The total stress due to the AFS isobtained as a sum of contributions from breaking fronts of different scales.Outside the breaking fronts the drag of the sea surface is supported by theviscous surface stress and the wave-induced stress. To calculate the stressdue to the AFS and the wave-induced stress a physical model of the wind-wavespectrum is used. Together with the model of the air flow described in termsof surface stresses it forms a self-consistent dynamical system for the seasurface-atmosphere where the air flow and wind waves are strongly coupled.Model calculations of the drag coefficient agree with measurements. It is shownthat the dimensionless Charnock parameter (roughness length normalized onthe square of the friction velocity and the acceleration of gravity)increases with the increase of the wind speed in agreement with fieldmeasurements. The stress due to the AFS normalized on the square of thefriction velocity is proportional to the cube of wind speed. At low windsthe viscous surface stress dominates the drag. The role of the form drag,which is the sum of the stress due to the AFS and the wave-induced stress, isnegligible. At moderate and high winds the form drag dominates. At windspeeds higher than 10 m s-1 the stress supported by the AFS becomescomparable to the wave-induced stress and supports up to 50% of the totalstress. 相似文献
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1萍乡市烟花鞭炮行业生产场所特点及雷击事故成因分析由于生产和贮存的特殊要求,烟花鞭炮生产场所主要有以下几个特点:一是大多建设在郊区的小山坡上,地势较高,土质干燥,且有部分为风化石,土壤电阻率较高;二是生产厂房等占地面积不大,高度较低,且相对分散,所以整个工厂面积较大;三是几乎所有的生产厂房、仓库都为“人”字形砖瓦结构建筑。由于种种原因,萍乡市烟花鞭炮行业95%以上的车间、仓库均未严格按照国家标准设计安装防雷装置。虽有极少数安装了防雷装置,但大部分防雷设计方案未经气象主管机构审核,防雷装置未请有专业资质的甲级单位施… 相似文献
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根据抚州市气象台Micaps V2．0的运行情况,从参数检索控制文件的本地化设置、主窗口显示的工具条及控件框本地化设置,以及制作必要的新底图文件、参数启动文件、批命令文件和定义综合图等方面,探讨了地市级气象台Micaps V2．0本地化过程中遇到的一些问题,以及解决办法和日常维护经验。这对县级台站的Micaps V2．0本地化设置也有一定的指导意义。 相似文献
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从主题的确定、要素的挖掘及表现、形式美法的应用等方面,详细介绍了江西省气象局徽标的设计过程。设计制作的江西省气象局徽标,通过环绕的橄榄枝代表世界气象,通过中间的中国气象局徽标代表中国气象,通过杜鹃花代表江西,进一步体现了江西气象部门在弘扬“管天为民、追求卓越”的江西气象精神的基础上,将立足江西、面向全国、走向世界,努力实现江西气象事业的跨越式发展,从而为建设“四个一流”的江西气象事业和建设和谐平安江西,做出更大的贡献。 相似文献
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Releases of halocarbons into the atmosphere over the last 50 years are among the factors that have contributed to changes in the Earth’s climate since pre-industrial times. Their individual and collective potential to contribute directly to surface climate change is usually gauged through calculation of their radiative efficiency, radiative forcing, and/or Global Warming Potential (GWP). For those halocarbons that contain chlorine and bromine, indirect effects on temperature via ozone layer depletion represent another way in which these gases affect climate. Further, halocarbons can also affect the temperature in the stratosphere. In this paper, we use a narrow-band radiative transfer model together with a range of climate models to examine the role of these gases on atmospheric temperatures in the stratosphere and troposphere. We evaluate in detail the halocarbon contributions to temperature changes at the tropical tropopause, and find that they have contributed a significant warming of ~0.4 K over the last 50 years, dominating the effect of the other well-mixed greenhouse gases at these levels. The fact that observed tropical temperatures have not warmed strongly suggests that other mechanisms may be countering this effect. In a climate model this warming of the tropopause layer is found to lead to a 6% smaller climate sensitivity for halocarbons on a globally averaged basis, compared to that for carbon dioxide changes. Using recent observations together with scenarios we also assess their past and predicted future direct and indirect roles on the evolution of surface temperature. We find that the indirect effect of stratospheric ozone depletion could have offset up to approximately half of the predicted past increases in surface temperature that would otherwise have occurred as a result of the direct effect of halocarbons. However, as ozone will likely recover in the next few decades, a slightly faster rate of warming should be expected from the net effect of halocarbons, and we find that together halocarbons could bring forward next century’s expected warming by ~20 years if future emissions projections are realized. In both the troposphere and stratosphere CFC-12 contributes most to the past temperature changes and the emissions projection considered suggest that HFC-134a could contribute most of the warming over the coming century. 相似文献
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综合布线系统采用标准化的语音、数据、图像、监控设备,各线综合配置在一套标准的布线系统上,统一布线设计、安装施工和集中管理维护。综合布线系统在广东省气象局核心网络升级综合布线实际应用效果明显。 相似文献
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Currently used and newly proposed calculation techniques for the heightof the stable boundary layer (SBL), including the bulk-Richardson-numbermethod, diagnostic equations for the equilibrium SBL height, and a relaxation-typeprognostic equation, are discussed from the point of view of their physical basis andrelevance to experimental data. Among diagnostic equations, the best fit to data exhibits an advanced Ekman-layer height model derived recently with due regard to the role of the free-flow stability. Its extension to non-steady regimes provides a prognostic equation recommended for use in practical applications. 相似文献