风云气象卫星的地面应用系统

我国从20世纪70年代开始实施自己的气象卫星计划，经过30多年的工作，已经建立起风云1号极轨和风云2号静止两个系列的气象卫星。地面应用系统是风云气象卫星大系统中的一个重要组成部分。文章就地面应用系统的规划工作、关键技术问题的解决以及业务运行成功率的提高等三个方面做了回顾；风云气象卫星已成为我国现代化气象业务系统中不可或缺的重要组成部分，并被世界气象组织正式列为世界天气监视网全球观测系统的一个组成部分；从气象卫星获取的大气和地表信息，已被广泛应用于天气预报、气候预测、环境和自然灾害监测、农业等多个国民经济领域；讨论了风云气象卫星地面应用系统成功的经验。     

中国的极轨气象卫星

气象卫星是具有巨大经济和社会效益的应用卫星，中国的极轨气象卫星经历了从试验阶段到业务应用阶段的发展历程。文章简要介绍了“风云一号”（FY-1）极轨气象卫星的发展概况和技术性能，星载十通道扫描辐射计和长寿命、高可靠极轨卫星平台取得的成功；重点介绍了中国新一代的极轨气象卫星“风云三号”（FY-3）的总体概况，归纳了卫星的技术特点。     

系统工程方法在风云三号极轨气象卫星地面应用系统工程中的应用

简要介绍了基于需求分析的风云三号（FY-3）卫星观测能力设计,并阐述了卫星地面应用系统如何利用系统工程方法进行地面系统顶层设计,统筹FY-3卫星和地面系统工程需求,合理布局地面接收站,科学划分地面系统各功能单元的任务,实现建成后的地面应用系统整体能力最大化。     

《中国工程科学》2006年第8卷第10期要目预告

深空探测与我国深空探测展望…………叶培建等中国的探月工程———中国航天的第三个里程碑……………栾恩杰风云气象卫星的地面应用系统…………许建民等我国天地一体化航天互联网构想…………沈荣骏中国通信及导航卫星技术与应用的发展…………………………………………范本尧航天测控系统的现状与发展………………于志坚中国空间对地观测技术发展现状及未来发展的思考…………………………………姜景山中国进入空间能力的发展与展望………王小军等资源卫星及我国的对地观测体系…………郭建宁天基发射与载人登月初探………………张泽明等…     

风云三号卫星先进微波大气探测仪系统设计与研制

先进微波大气探测仪(AMAS)是安装在风云三号卫星(C/D星)上的新一代微波湿度计,是风云三号卫星(A/B星)微波湿度计的继承和发展。在150 GHz(水平极化和垂直极化)和183.31 GHz(水平极化,三通道)的基础上,探测频率和通道设置为89 GHz(垂直极化)、118.75 GHz(水平极化,八通道)、150 GHz(垂直极化)、183.31 GHz(水平极化,五通道),仍采用垂直于飞行方向的交轨扫描方式,科学目标是探测全球大气温度和湿度的垂直分布、降雨等。本文介绍了微波湿度计-II的系统设计与构成,描述了微波湿度计-II的性能指标要求。测试结果表明,性能指标满足设计要求。     

海洋二号卫星工程研制及在轨运行简介

海洋二号卫星是我国首颗海洋动力环境探测卫星,也是目前国际上唯一一颗可全天候、全天时同步获取全球海面高度、有效波高、海面风场、海面风速、海面温度、大气水汽含量、云中液水含量等多种遥感数据的卫星。海洋二号卫星配置4种主、被动微波遥感载荷,采用全新遥感体制,实现关键部件国产化,具有精密测定轨、电磁兼容、高精度姿态控制等技术特点。海洋二号卫星作为国内首颗综合型微波遥感卫星,其工程实现意义重大。本文从系统组成与功能、研制阶段划分、大型试验验证、在轨测试与应用成果展示几个方面进行了介绍。     

FY-3A/MWHS在轨辐射定标及结果分析

风云三号A星微波湿度计(FY-3A/MWHS)是我国首次在轨定量遥感大气参数的高频微波辐射计,本文以发射前地面真空试验数据为基础完成了FY-3A/MWHS在轨辐射定标,利用同期在轨的同类载荷NOAA/AMSU-B数据进行在轨辐射定标对比分析,结果表明FY-3A/MWHS在轨星上定标观测基础数据在卫星绕地飞行一圈的观测过程中变化合理,经非线性偏差订正和天线订正等辐射定标处理后,FY-3A/MWHS与NOAA-17/AMSU-B对应通道定标结果相比匹配目标点通道亮温差最大不超过1.5 K,FY-3A/MWHS在轨辐射定标结果为其资料在数值天气预报模式中的同化以及大气参数反演等定量应用奠定了基础。FY-3A/MWHS定标及结果分析方法对我国未来星载被动微波探测器的在轨定量应用具有示范意义。     

风云三号气象卫星微波温度计（MWTS）

微波温度计是一个多通道的被动微波辐射计,用于风云三号气象卫星,风云三号工作在太阳同步轨道。本文描述了微波温度计的功能和性能,微波温度计系统由天线子系统、接收子系统、信号处理和控制子系统、定标子系统和扫描伺服子系统组成,微波温度计的4个接收通道的中心频率分别为50.30 GHz、53.596 GHz、54.94 GHz和57.29 GHz,用于探测大气垂直温度分布。     

风云三号A星微波湿度计数据处理与应用

主要介绍了风云三号A星（FY-3A）有效载荷之一——微波湿度计的结构、运行状态以及数据接收和数据处理的具体形式。利用神经网络算法建立反演模型,并与国外已经业务运行的先进微波探测单元B型（AMSU-B）比较,性能相当。反演北京地区2008年7—12月相对湿度和水汽密度廓线,对比探空数据,分析反演均方差。同时,分析了台风到来时不同通道的亮温显示结果,从而证明：风云三号微波湿度计不仅能全球范围内探测大气水汽等相关信息,同样在台风、热带气旋的检测和判断未来的走势中也发挥了重要作用。     

HY-2卫星激光观测精密定轨技术

2011年8月16日发射的海洋二号(HY-2)卫星是中国第一颗海洋动力环境卫星,配备的卫星激光测距跟踪系统即作为HY-2卫星定轨基准系统,同时又是HY-2卫星定轨系统之一。本文较为详细地介绍了HY-2卫星激光观测、轨道预报和激光跟踪系统(SLR)定轨技术,并对SLR定轨结果进行了初步检验。     

Detection of Precipitation Cloud over the Tibet Based on the Improved U-Net

Aiming at the problem of radar base and ground observation stations on the Tibet is sparsely distributed and cannot achieve large-scale precipitation monitoring. UNet, an advanced machine learning (ML) method, is used to develop a robust and rapid algorithm for precipitating cloud detection based on the new-generation geostationary satellite of FengYun-4A (FY-4A). First, in this algorithm, the real-time multi-band infrared brightness temperature from FY-4A combined with the data of Digital Elevation Model (DEM) has been used as predictor variables for our model. Second, the efficiency of the feature was improved by changing the traditional convolution layer serial connection method of U-Net to residual mapping. Then, in order to solve the problem of the network that would produce semantic differences when directly concentrated with low-level and high-level features, we use dense skip pathways to reuse feature maps of different layers as inputs for concatenate neural networks feature layers from different depths. Finally, according to the characteristics of precipitation clouds, the pooling layer of U-Net was replaced by a convolution operation to realize the detection of small precipitation clouds. It was experimentally concluded that the Pixel Accuracy (PA) and Mean Intersection over Union (MIoU) of the improved U-Net on the test set could reach 0.916 and 0.928, the detection of precipitation clouds over Tibet were well actualized.     

HY-2卫星微波散射计在西北太平洋台风监测中的应用研究

本文在简述海洋二号(HY-2)卫星微波散射计工作机制及海面风场反演原理的基础上,针对HY-2卫星微波散射计在轨运行的数据,利用该散射计数据开展海面台风中心定位、结构、台风路径、风速等值线、大风半径等台风参数的定量化应用分析研究。同时将HY-2卫星观测到的海面风场与风云二号(FY-2E)卫星云图进行融合展示,并将HY-2海面风场与ASCAT反演的海面风场和浮标提供的观测数据进行对比验证,多方面的定量分析显示出HY-2卫星海面风场观测的有效性和在台风监测中的优势。最后,对HY-2卫星微波散射计的优缺点进行分析,展望了其可能的改进方向。     

中国极地大气科学观测工程

极地位于地球南北两端,是全球变化研究的关键地区,要了解全球变化,特别是全球气候变化,必须对极地有所研究。我国的南极和北极实地科学考察研究,分别始于20世纪80年代和90年代。作为国家行为,到2011年年底,组织了28次南极考察、4次北冰洋考察和8次北极陆地考察;在南北极建立了4个科学考察站6,个自动气象站;形成了以有人考察站、无人自动气象站和"雪龙"号破冰科学考察船为主体的极地科学考察研究硬件支撑体系。在此过程中初步建成了包括常规气象业务、准业务和短期考察在内的中国极地大气科学观测工程体系;该技术系统所获科学数据已在我国极地科学研究中广泛应用,并在国内外产生了重大影响。     

A methodology for probabilistic predictions of regional climate change from perturbed physics ensembles

A methodology is described for probabilistic predictions of future climate. This is based on a set of ensemble simulations of equilibrium and time-dependent changes, carried out by perturbing poorly constrained parameters controlling key physical and biogeochemical processes in the HadCM3 coupled ocean-atmosphere global climate model. These (ongoing) experiments allow quantification of the effects of earth system modelling uncertainties and internal climate variability on feedbacks likely to exert a significant influence on twenty-first century climate at large regional scales. A further ensemble of regional climate simulations at 25km resolution is being produced for Europe, allowing the specification of probabilistic predictions at spatial scales required for studies of climate impacts. The ensemble simulations are processed using a set of statistical procedures, the centrepiece of which is a Bayesian statistical framework designed for use with complex but imperfect models. This supports the generation of probabilities constrained by a wide range of observational metrics, and also by expert-specified prior distributions defining the model parameter space. The Bayesian framework also accounts for additional uncertainty introduced by structural modelling errors, which are estimated using our ensembles to predict the results of alternative climate models containing different structural assumptions. This facilitates the generation of probabilistic predictions combining information from perturbed physics and multi-model ensemble simulations. The methodology makes extensive use of emulation and scaling techniques trained on climate model results. These are used to sample the equilibrium response to doubled carbon dioxide at any required point in the parameter space of surface and atmospheric processes, to sample time-dependent changes by combining this information with ensembles sampling uncertainties in the transient response of a wider set of earth system processes, and to sample changes at local scales.The methodology is necessarily dependent on a number of expert choices, which are highlighted throughout the paper.     

关于气候变化的哲学思考

从哲学的基本原理出发,引用地史及水文气象资料探讨了全球气候变化问题,指出全球气候一直在变化;气候变化的动力主要在天在地而不在人;当今的气候变化可能只是气候变化总过程中的一个波动阶段而非永远的趋势,且其变幅并未超出历史上气候变化的范畴。因此,不能断言全球气候变暖是由于人为排放CO2所致。所以对于不同时空条件下的气候变化应当具体矛盾具体分析具体解决,进而提出了中国应对气候变化的对策建议。     

Climate change and trace gases

Palaeoclimate data show that the Earth's climate is remarkably sensitive to global forcings. Positive feedbacks predominate. This allows the entire planet to be whipsawed between climate states. One feedback, the 'albedo flip' property of ice/water, provides a powerful trigger mechanism. A climate forcing that 'flips' the albedo of a sufficient portion of an ice sheet can spark a cataclysm. Inertia of ice sheet and ocean provides only moderate delay to ice sheet disintegration and a burst of added global warming. Recent greenhouse gas (GHG) emissions place the Earth perilously close to dramatic climate change that could run out of our control, with great dangers for humans and other creatures. Carbon dioxide (CO2) is the largest human-made climate forcing, but other trace constituents are also important. Only intense simultaneous efforts to slow CO2 emissions and reduce non-CO2 forcings can keep climate within or near the range of the past million years. The most important of the non-CO2 forcings is methane (CH4), as it causes the second largest human-made GHG climate forcing and is the principal cause of increased tropospheric ozone (O3), which is the third largest GHG forcing. Nitrous oxide (N2O) should also be a focus of climate mitigation efforts. Black carbon ('black soot') has a high global warming potential (approx. 2000, 500 and 200 for 20, 100 and 500 years, respectively) and deserves greater attention. Some forcings are especially effective at high latitudes, so concerted efforts to reduce their emissions could preserve Arctic ice, while also having major benefits for human health, agricultural productivity and the global environment.     

Efficient global monitoring statistics for high-dimensional data

Global monitoring statistics play an important role in developing efficient monitoring schemes for high-dimensional data. A number of global monitoring statistics have been proposed in the literature. However, most of them only work for certain types of abnormal scenarios under specific model assumptions. How to develop global monitoring statistics that are powerful for any abnormal scenarios under flexible model assumptions is a long-standing problem in the statistical process monitoring field. To provide a potential solution to this problem, we propose a novel class of global monitoring statistics. Our proposed global monitoring statistics are easy to calculate and can work under flexible model assumptions since they can be built on any local monitoring statistic that is suitable for monitoring a single data stream. Our simulation studies show that the proposed global monitoring statistics perform well across a broad range of settings and compare favorably with existing methods.     

Predictions of extreme precipitation and sea-level rise under climate change

Two aspects of global climate change are particularly relevant to river and coastal flooding: changes in extreme precipitation and changes in sea level. In this paper we summarize the relevant findings of the IPCC Third Assessment Report and illustrate some of the common results found by the current generation of coupled atmosphere-ocean general circulation models (AOGCMs), using the Hadley Centre models. Projections of changes in extreme precipitation, sea-level rise and storm surges affecting the UK will be shown from the Hadley Centre regional models and the Proudman Oceanographic Laboratory storm-surge model. A common finding from AOGCMs is that in a warmer climate the intensity of precipitation will increase due to a more intense hydrological cycle. This leads to reduced return periods (i.e. more frequent occurrences) of extreme precipitation in many locations. The Hadley Centre regional model simulates reduced return periods of extreme precipitation in a number of flood-sensitive areas of the UK. In addition, simulated changes in storminess and a rise in average sea level around the UK lead to reduced return periods of extreme high coastal water events. The confidence in all these results is limited by poor spatial resolution in global coupled models and by uncertainties in the physical processes in both global and regional models, and is specific to the climate change scenario used.     

ELPIS-JP: a dataset of local-scale daily climate change scenarios for Japan

We developed a dataset of local-scale daily climate change scenarios for Japan (called ELPIS-JP) using the stochastic weather generators (WGs) LARS-WG and, in part, WXGEN. The ELPIS-JP dataset is based on the observed (or estimated) daily weather data for seven climatic variables (daily mean, maximum and minimum temperatures; precipitation; solar radiation; relative humidity; and wind speed) at 938 sites in Japan and climate projections from the multi-model ensemble of global climate models (GCMs) used in the coupled model intercomparison project (CMIP3) and multi-model ensemble of regional climate models form the Japanese downscaling project (called S-5-3). The capability of the WGs to reproduce the statistical features of the observed data for the period 1981-2000 is assessed using several statistical tests and quantile-quantile plots. Overall performance of the WGs was good. The ELPIS-JP dataset consists of two types of daily data: (i) the transient scenarios throughout the twenty-first century using projections from 10 CMIP3 GCMs under three emission scenarios (A1B, A2 and B1) and (ii) the time-slice scenarios for the period 2081-2100 using projections from three S-5-3 regional climate models. The ELPIS-JP dataset is designed to be used in conjunction with process-based impact models (e.g. crop models) for assessment, not only the impacts of mean climate change but also the impacts of changes in climate variability, wet/dry spells and extreme events, as well as the uncertainty of future impacts associated with climate models and emission scenarios. The ELPIS-JP offers an excellent platform for probabilistic assessment of climate change impacts and potential adaptation at a local scale in Japan.