重庆地区夏季一次降水过程及增雨潜力的数值模拟分析

利用国家气象中心GRAPES人工增雨云系模式,选取2008年7月4日重庆地区一次降水过程进行数值模拟,分析了重庆地区降雨天气的水汽分布、云系宏微观分布、云中微物理转化和增雨潜力等特征。结果表明：本次降水大气过程中,重庆地区水汽含量极为丰富,水汽分布与地形分布呈明显的对应关系,低层水汽输送较大,整层水汽通量较高,有明显水汽辐合,云中液态水对地面降水影响很大。西南气流和地形共同作用为重庆地区液态水的形成提供了有利条件,在东北部山区迎风坡处大量水汽累积抬升,易形成丰富的液态水。重庆东北部地区水汽向云水转化较强,过冷液态水含量丰富,冰晶含量少,0℃层附近水汽垂直通量较大,降水效率较低,有较大的增雨潜力。     

呼和浩特—包头盆地震源应力场状态分析

为了分析呼和浩特—包头盆地现今应力场状态,基于内蒙古地震台网记录的地震波形资料,运用振幅比方法获取2000—2016年该盆地及周边M_L≥2.7地震的震源机制解,计算其一致性参数,并反演区域应力场。结果表明,震源机制解特征主要表现为走滑特征,一致性参数空间分布处于低值状态,力轴方位基本与该区的应力场背景特征相符,即主压应力方位为北东、张应力方位为北西。     

An Improved Approach for Parameterizing Surface-Layer Turbulent Transfer Coefficients in Numerical Models

Based on classic iterative computation results, new equations to calculate the surface turbulent transfer coefficients are proposed, which allow for large ratios of the momentum and heat roughness lengths. Compared to the Launiainen scheme, our proposed scheme generates results closer to classical iterative computations. Under unstable stratification, the relative error in the Launiainen scheme increases linearly with increasing instability, even exceeding 15%, while the relative error of the present scheme is always less than 8.5%. Under stable stratification, the Launiainen scheme uses two equations, one for 0 < Ri _B ≤ 0.08 and another for 0.08 < Ri _B ≤ 0.2, and does not consider the condition that Ri _B > 0.2, while its relative errors in the region 0 < Ri _B ≤ 0.2 exceed 31 and 24% for momentum and heat transfer coefficients, respectively. In contrast, the present scheme uses only one equation for 0 < Ri _B ≤ 0.2 and another equation for Ri _B > 0.2, and the relative error of the present scheme is always less than 14%.     

DYYZ-Ⅱ型自动气象站测温故障排除方法与思路

文章通过DYYZ-Ⅱ型自动气象站出现的一次气温、地温数据缺测故障,分析了DYYZ-Ⅱ型自动气象站出现测温故障时的故障排除过程与排除思路,为保障技术人员在处理此类故障时提供了方法和依据。     

Assessment of PPP integer ambiguity resolution using GPS,GLONASS and BeiDou (IGSO,MEO) constellations

Although integer ambiguity resolution (IAR) can improve positioning accuracy considerably and shorten the convergence time of precise point positioning (PPP), it requires an initialization time of over 30 min. With the full operation of GLONASS globally and BDS in the Asia–Pacific region, it is necessary to assess the PPP–IAR performance by simultaneous fixing of GPS, GLONASS, and BDS ambiguities. This study proposed a GPS + GLONASS + BDS combined PPP–IAR strategy and processed PPP–IAR kinematically and statically using one week of data collected at 20 static stations. The undifferenced wide- and narrow-lane fractional cycle biases for GPS, GLONASS, and BDS were estimated using a regional network, and undifferenced PPP ambiguity resolution was performed to assess the contribution of multi-GNSSs. Generally, over 99% of a posteriori residuals of wide-lane ambiguities were within ±0.25 cycles for both GPS and BDS, while the value was 91.5% for GLONASS. Over 96% of narrow-lane residuals were within ±0.15 cycles for GPS, GLONASS, and BDS. For kinematic PPP with a 10-min observation time, only 16.2% of all cases could be fixed with GPS alone. However, adding GLONASS improved the percentage considerably to 75.9%, and it reached 90.0% when using GPS + GLONASS + BDS. Not all epochs could be fixed with a correct set of ambiguities; therefore, we defined the ratio of the number of epochs with correctly fixed ambiguities to the number of all fixed epochs as the correct fixing rate (CFR). Because partial ambiguity fixing was used, when more than five ambiguities were fixed correctly, we considered the epoch correctly fixed. For the small ratio criteria of 2.0, the CFR improved considerably from 51.7% for GPS alone, to 98.3% when using GPS + GLONASS + BDS combined solutions.     

Test method for single interior right angle in a corner cube prism

1　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｃｏｒｎｅｒｃｕｂｅｐｒｉｓｍｏｒｒｅｔｒｏｒｅｆｌｅｃｔｏｒｉｓｅｘｔｅｎ ｓｉｖｅｌｙｕｓｅｄｉｎｐｌａｃｅｏｆｔｈｅｍｏｖａｂｌｅｍｉｒｒｏｒｉｎａｎｉｎ ｔｅｒｆｅｒｏｍｅｔｅｒ,ｏｒａｓａｃｏｏｐｅｒａｔｉｖｅｔａｒｇｅｔｉｎｒａｎｇｅｆｉｎｄｅｒ.Ｉｔｈａｓｔｈｒｅｅｓｕｒｆａｃｅｓ,ｗｈｉｃｈａｒｅｐｅｒｐｅｎｄｉｃ ｕｌａｒｔｏｅａｃｈｏｔｈｅｒａｎｄｃａｌｌｅｄｔｈｅｒｉｇｈｔａｎｇｕｌａｒｓｕｒ ｆａｃｅｓ.Ａｎｉｎｃｌｉｎｅｄｉｓｏｓｃｅｌｅｓｔｒ…     

基于水质荧光指纹法的湖泊污染溯源研究——以太湖流域滆湖为例

随着社会经济和城市化进程的快速发展,湖泊水环境污染问题日益突出,加剧了湖泊原有功能的退化和丧失,因此污染治理成为了湖泊功能恢复和可持续发挥的必要条件,但如何实现污染精准溯源又是污染治理的重要前提。为此,本文以太湖流域滆湖为例,采用一种新兴技术——水质荧光指纹法开展湖泊污染溯源。于2021年累计采集滆湖周边70个农业、13个生活、3个企业排口的瞬时出水构建污染源荧光指纹库,连续12个月采集滆湖湖体8个样点水样分析水体荧光组分。通过平行因子分析共解析出4种污染源指纹和滆湖5种水体组分,经荧光相似度(塔克同余系数)分析进一步明确滆湖主要受到种植业面源、生活源和工业源的影响。此外,荧光强度与叶绿素a浓度和藻密度的强相关性表明藻类繁殖活动也会影响滆湖。从不同污染源对滆湖的时空影响特征来看,种植业面源主要在春、夏季影响西部、中部水域,生活源主要在夏、冬季影响西部、北部水域,工业源主要在特定月份(3 4月、10 12月)影响西部水域,藻类繁殖活动主要在夏季影响湖体。通过荧光组分与水质参数的时空相关性分析得到农业源和总磷、总氮,生活源和氨氮、有机物参数(BOD₅、COD_...     

Primary dolostone related to the Cretaceous lacustrine hydrothermal sedimentation in Qingxi sag, Jiuquan Basin on the northern Tibetan Plateau

Based on comprehensive studies in petrography, petrofabric analysis and geochemistry, this paper describes a unique and rare laminated micritic ferruginous primary dolostone crystallized and precipitated from the alkaline hot brine under the conditions of the Mesozoic faulted lake basin. The main rock-forming mineral of this dolostone is ferruginous dolomite with a micritic structure. This dolomite mostly exhibits laminae of 0.1–1 mm thick and is often discovered with other minerals, such as albite, analcite, barite and dickite, which have at least two types of interbedded laminae. Petrogeochemistry reveals that this dolostone contains a large number of typomorphic elements of hydrothermal sedimentation, including Sb, Ba, Sr, Mn, and V. In addition, the LREE is in relatively high concentrations and possesses the typical REE distribution pattern with negative Eu anomaly. Oxygen isotope values (δ¹⁸O_PDB) range from 5.89‰ to 14.15‰ with an average of 9.69‰. The ratio of ⁸⁷Sr/⁸⁶Sr is between 0.711648 and 0.719546, with an average of 0.714718. These data indicate that the depositional environment is a stable, blocked, anoxic low-lying hot brine pool in the bottom of deep lake controlled by basement faults. The hydrothermal fluid is the alkaline hot brine formed by the combination of the infiltration lake water and mantle-derived magmatic water, consisting of many ions, including Ca²⁺, Mg²⁺ and Fe²⁺. Under the driving flow power of magmatic heat, gravity and compaction, the hydrothermal fluid overcame the overburden pressure and hydrostatic pressure of the lake water body, and boiled to explosion, and then the explosion shattered the original laminated micritic ferruginous primary dolostone near the vent and then formed a new type of dolostone called shattered “hydroexplosion breccias”. In the low-lying, unperturbed hot brine pool, far from the vent, the laminated micritic ferruginous primary dolostone was quickly crystallized and chemicals precipitated from the hydrotherm. This study of special rocks contributes to research into the causes of the formation of lacustrine carbonate rocks and dolostone. In particular, it provides new examples and research insights for future studies of the lacustrine dolomite from the similar Mesozoic and Cenozoic basins in China.     

风电场风资源测量与计算的精度控制

根据多个复杂地形风电场观测操作实践和大量观测数据的计算分析,提出了对观测数据和计算质量精度控制的主要措施,包括:复杂地形测风站布设的5个原则,仪器的合理选型和设置;对由于测风仪固有的系统误差和缺测数据的插补订正可能引起的计算误差进行了定量估算,通过对大量实测数据的对比计算显示:①目前普遍采用的进口风速计的相对偏差在1.6%～5.25%之间,由此可导致轮毂高度附近的年平均风功率密度误差在5%以上,最大达13.8%;②在季风气候区、复杂地形和风的年变率较大的地区,进行缺测数据插补订正时,应选取同季或同一主导风向的数据作为插补订正的基础数据,否则可能导致其平均风功率密度相对误差达20%～50%.     

国土资源科技基础信息分析系统的设计与实现

本文从需求分析、系统整体设计、系统实现与应用三个方面介绍了国土资源科技基础信息分析系统。系统旨在实现科技统计数据采集、传输、审核、汇总、管理与分析的全流程信息化,创新科技信息服务,为国土资源科技管理与决策提供服务和支撑。