农业气象信息资源管理的几点设想

在对各地农气中心"农气文献资源数据库"现状调研的基础上,针对发展现代化农业对农气服务的需求,对"数据库"及"文献馆"的开发与管理方案进行了探讨.     

农业气象信息资源管理的几点设想

在对各地农艺中心“农气文献资源数据库”现状调研的基础上，针对发展现代化农业对农气服务的需要，对“数据库”及“文献馆”的开发与管理方案进行了探讨。     

黑龙江省2000年农业气象灾害综述

详细分析了2000年各种农业气象灾害及灾情的时空分布，为农业抗荧积累资料，为政府决策提供科学依据。     

广州智慧农业气象服务平台设计与实现

基于国家对农业信息化数字农业发展要求,以及广州都市农业发展需求分析,探讨了广州智慧农业气象服务平台构建策略、建设规划,重点探讨通过可视化建模方式,以及通用算法和集合算法,方便业务人员自行构建农业气象业务应用模型;采用CiteSpace技术构建农业气象知识图谱,实现“惠农”AI互动;通过Scrapy网络爬虫技术、Spark ML卷积神经网络算法,实现病虫害图像识别与趋势分析;应用基于GIS二三位一体化技术实现精细化的气候资源区划、气象灾害风险区划;采用Web系统与微信混合式服务方式,提供多个特色农业气象服务。旨在以平台为载体,通过农业气象智能化信息化建设,推进粤港澳大湾区“菜篮子”工程建设,推动农村产业规模和科技创新发展,促进农村一二三产业融合发展,实现农业生产风险有效转移,有效保障广州都市农业发展。     

Shifts in African crop climates by 2050, and the implications for crop improvement and genetic resources conservation

Increased understanding of the substantial threat climate change poses to agriculture has not been met with a similarly improved understanding of how best to respond. Here we examine likely shifts in crop climates in Sub-Saharan Africa under climate change to 2050, and explore the implications for agricultural adaptation, with particular focus on identifying priorities in crop breeding and the conservation of crop genetic resources. We find that for three of Africa's primary cereal crops – maize, millet, and sorghum – expected changes in growing season temperature are considerable and dwarf changes projected for precipitation, with the warmest recent temperatures on average cooler than almost 9 out of 10 expected observations by 2050. For the “novel” crop climates currently unrepresented in each country but likely extant there in 2050, we identify current analogs across the continent. The majority of African countries will have novel climates over at least half of their current crop area by 2050. Of these countries, 75% will have novel climates with analogs in the current climate of at least five other countries, suggesting that international movement of germplasm will be necessary for adaptation. A more troubling set of countries – largely the hotter Sahelian countries – will have climates with few analogs for any crop. Finally, we identify countries, such as Sudan, Cameroon, and Nigeria, whose current crop areas are analogs to many future climates but that are poorly represented in major genebanks – promising locations in which to focus future genetic resource conservation efforts.     

Studies of sensitivity of a dynamic model of grain crop productivity to soil-hydrophysical information

The relationship between a target function of a mathematical model of grain crop growth and development—yield—and variations in the soil and hydrophysical information expressed by variations in the soil water-retention function is considered. The function is approximated with a formula based on soil-hydrological constants. The soil profile in the model is represented by a three-layer structure. Each layer has its own agrohydrological characteristics: maximal hygroscopic moisture, wilting moisture, the least moisture capacity, and saturation moisture. The model AGROTOOL, identified from long-term data on field experiment at the Men’kovo experiment station of the Agrophysical Research Institute (the Leningrad region), is used to estimate the influence of variations in these sets on the barley and winter rye yield. It is demonstrated that the yield is most sensitive to variations in the least moisture capacity of the soil and has the least sensitivity to the change in the maximal hygroscopic moisture.     

Estimating the level of territory vulnerability and climate-related risk of significant grain crop failure in grain-producing regions of Russia

A term ofclimate-related risk ofcrop losses due to adverse hydrometeorological conditions is introduced. The level of territory vulnerability in terms ofcrop production is defined by the relationship between the yield of a given crop and the bioclimatic potential of a territory. The estimates of vulnerability and crop failure risks for some grain crops are presented for the period of 1994–2013. Average for Russia crop failure risk for spring and winter wheat computed taking into account the cultivated areas is 12.5 and 10.6%, respectively. It is revealed that the most parts of the Southern and Volga federal districts are located in the high-risk zone. Areas ofrelatively low risks in terms ofcrop failure for spring and winter wheat are the Siberian and Central federal districts.     

农业气象信息网自助生成系统设计与实现

接口层位于用户端,相当于用户界面。用户端分为3级用户：一般用户、单位信息管理员、超级管理员,通过用户端浏览网页信息,维护网页数据和网站结构。     

Scientific basis of agrometeorological and agroclimatic support to the agrarian sector of the Russian economy

Results are reviewed of the studies aimed at the development of current techniques for estimation of bioclimatic potential of Russia to provide agrometeorological support to the agrarian sector of economy under the present-day conditions. Problems are considered of estimating and accounting the effects of the climate changes on productivity and long-term stability of agriculture. Results are presented of using the satellite information for operative monitoring of condition and productivity of agriculture. It is shown that the studies carried out at All-Russian Research Institute of Agricultural Meteorology (VNIISKhM) allow creating a complex system for operative agrometeorological monitoring on the basis of the modern models of the agro-ecosystem productivity. The system will allow regular estimating of conditions, expected harvest and total yield in the times specified by Roshydromet and presenting a set of their probability estimates as dependent on the predicted weather. As a result, all levels of the agriculture, from the farmers to the Ministry of Agriculture, will be provided with agrometeorological and agroclimatic information.     

How adoption rates, timing, and ceilings affect the value of ENSO-based climate forecasts

An international wheat trade model incorporating climate variability is used to simulate different scenarios when wheat producers in the USA, Canada, and Australia adopt El Niño/Southern Oscillation (ENSO)-based climate forecasts for use in production decisions. Adoption timing and rates are varied across countries in the different scenarios. The results are consistent between the scenarios examined. Early adopters benefit the most, there is no incentive for more producers to adopt after 60 to 95% have adopted (meaning the adoption ceiling has been reached), and slower adoption corresponds to ceilings closer to 60 than 95%. When individual countries must decide whether or not to invest in ENSO technology and producer education programs to encourage adoption, results indicate the dominant strategy for each country is to invest. This is especially true if producers in other countries are adopting the use of climate forecasts.     

Seasonal forecasts for regional onset of the West African monsoon

The West African monsoon has over the years proven difficult to represent in global coupled models. The current operational seasonal forecasting system of the UK Met Office (GloSea4) has a good representation of monsoon rainfall over West Africa. It reproduces the various stages of the monsoon: a coastal phase in May and June, followed by onset of the Sahelian phase in July when rainfall maxima shift northward of 10N until September; and a secondary coastal rainfall maximum in October. We explore the dynamics of monsoon onset in GloSea4 and compare it to reanalyses. An important difference is the change in the Saharan heat low around the time of Sahelian onset. In Glosea4 the deepening heat low introduces moisture convergence across an east-west Sahelian band, whereas in the reanalyses such an east-west organisation of moisture does not occur and moisture is transported northwards to the Sahara. Lack of observations in the southern Sahara makes it difficult to verify this process in GloSea4 and also suggests that reanalyses may not be strongly constrained by station observations in an area key to Sahelian onset. Timing of monsoon onset has socio-economic importance for many countries in West Africa and we explore onset predictability in GloSea4. We use tercile categories to calculate probabilities for onset occurring before, near and after average in four different onset indicators. Glosea4 has modest skill at 2–3 months’ lead time, with ROC scores of 0.6–0.8. Similar skill is seen in hindcasts with models from the ENSEMBLES project, even in models with large rainfall biases over the Sahel. Forecast skill derives from tropical SST in June and many models capture at least the influence of the tropical Atlantic. This suggests that long-range skill for onset could be present in other seasonal forecasting systems in spite of mean rainfall biases.     

华东地区地面和高空风场的多模式集成精细化预报研究

基于欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)、中国国家气象中心业务运行的中尺度数值预报系统(Global/Regional Assimilation and Prediction Enhanced System Meso, GRAPES-Meso)、美国国家环境预报中心(National Centers for Environmental Prediction, NCEP)的全球预报系统(Global Forecast System, GFS)、GRAPES全球预报系统(GRAPES-GFS)4个模式风场预报资料,利用双线性、反距离加权、三次样条、克里格等插值方法对华东及周边地区(110°～130°E,20°～40°N)2020年1—4月逐日地面和高空风0～72 h集合预报资料进行降尺度处理,得到满足机场及终端区气象保障的精细化风场预报。此外,还对精细化风场预报做多模式集成。结果表明,对于风场的精细化格点预报,反距离加权插值方法误差最小,为最优水平插值方法。基于扩展复卡尔曼滤波的多模式集成...     

Statistical adjustment,calibration and downscaling of seasonal forecasts: a case-study for Southeast Asia

Climate Dynamics - The present paper is a follow-on of the work presented in Manzanas et al. (Clim Dyn 53(3–4):1287–1305, 2019) which provides a comprehensive intercomparison...     

Organization of convection and monsoon forecasts

Summary In this paper we address the issue of monsoon forecasts in relation to the organization of convection. Given a physical initialization procedure, within a data assimilation, it is possible to use the detailed distribution of rainfall from mesoconvective precipitating elements to define the initial state of a global model. If that is carried out using a very high resolution model then the initial state can carry within it an organization of convection within the resolvable scales. Then the impact of physical initialization on the maintenance and prediction of tropical weather such as the monsoon can be determined. Lacking such an initialization, one can expect the convectively driven energetics to be biased, and a slow degradation of the forecasts can follow. Several examples of forecasts at different resolutions are discussed here. The main findings of this study are that improved forecast results are obtained when physical initialization is invoked where the observed rain and the model resolution are comparable, i.e. the footprint of the highest resolutions rainfall estimates obtained from satellite based data sets (principally we use the SSM/I instrument over the oceans). At this resolution, we note that the model is able to carry an organization of convection in the initialization and in the forecasts through the medium-range time scale.We have compared our results of monsoon studies at a resolution T255 with those at resolution T62. The transform grid separation at the resolution T255 is approximately 50 km and at the resolution T62, it is approximately 200 km. We find that the model at the higher resolution (T255) performs better and has more realistic energy conversions for the convectively driven synoptic scale monsoon.An organization of convection, at the synoptic scales, is not seen in the forecasts at lower resolutions, T62, where the rainfall patterns are generally much broader and tend to be more zonal. Such organization appears more realistic at the resolution T255. Variances of the energy conversion, calculated in the two-dimensional spectral space, from physically initialized short range forecasts at the higher resolution are seen to be largest on the scales of the monsoon. Similar calculations for the reanalyzed fields at lower resolutions show the spectral distribution of variances to be biased towards local Hadley scale overturnings.With 12 Figures     

Verification of Toronto temperature and precipitation forecasts for the period 1960–1979

Abstract

The accuracy of temperature and precipitation forecasts for Toronto was studied for the 20‐year period 1960–1979. Since any archive of official forecasts extends for only a small part of this period, it was necessary to retrieve the forecasts from newspaper records. The possible errors involved in such a data source were examined through a comparison of newspaper reported observations and the official record. On only a few occasions were significant differences observed.

For temperature forecasts, the record indicates a significant loss of skill over the 20‐year periodin the prediction of maximum temperature for the first day. This was observed not only for the Bloor Street observing station for which the entire 20‐year record was analysed, but also for observing stations at Toronto Island, Downsview and Malton. The loss of skill over the years is greatest in winter when temperature is consistently predicted too low at all stations.

For the entire period under study, precipitation forecasts consisted only of words and no quantitative information (such as probability of precipitation forecasts) was issued. Word choice is intended to carry information on the duration and expected spatial coverage of precipitation, but substantial inconsistencies between word choice and subsequent precipitation occurrence were found. Consequently, the verification procedure for these forecasts was very simple and ignored any differences implied in word choice. With this technique precipitation forecasts were shown to have improved over the 20‐year period.     

Skill of synthetic superensemble hurricane forecasts for the Canadian maritime provinces

Summary From 1994 to 2003, fifty-five tropical cyclones entered the Canadian Hurricane Centre (CHC) Response Zone, or about 42% of all named Atlantic tropical cyclones in this ten-year period, and 2003 was the fourth consecutive year for a tropical cyclone to make landfall in Canada. The CHC forecasts all tropical cyclones that enter the CHC Response Zone and assumes the lead in forecasting once the cyclone enters its area of forecast responsibility. This study acknowledges the challenges of forecasting such tropical cyclones at extratropical latitudes. If a tropical cyclone has been declared extratropical, global models may no longer use vortex bogussing to carry the cyclone, and even if it is modeled, large model errors often result. The purpose of this study is to develop a new version of the Florida State University (FSU) hurricane superensemble with greater skill in tracking tropical cyclones, especially at extratropical latitudes. This has been achieved from the development of the synthetic superensemble, which is similar to the operational version of the multi-model superensemble that is used at FSU. The synthetic superensemble differs in that is has a larger set of member models consisting of regular member models, synthetic versions of these models, and the operational superensemble and its synthetic version. This synthetic superensemble is being used here to forecast hurricane tracks from the 2001, 2002, and 2003 hurricane seasons. The track forecasts from this method have generally less error than those of the member models, the operational superensemble, and the ensemble mean. This study shows that the synthetic superensemble performs consistently well and would be an asset to operational hurricane track forecasting.     

Using the spectral scaling exponent for validation of quantitative precipitation forecasts

This study evaluates the spectral scaling of a heavy rainfall event and assesses the performance of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) model in terms of the multiscale variability of rainfall in the temporal spectral domain. The event occurred over southern Malay Peninsula on 18 December 2006 and was simulated at high resolutions. 10, 5 and 1?min aggregate rainfall data from rain gauge stations in Singapore and simulated rainfall sampled at different evaluation points on 0.9, 0.3 and 0.1?km grids were utilized. The simulated and observed rain rates were compared via Fourier and wavelet analyses. A scaling regime was noted in the observed rainfall spectra in the timescales between 60?min and 2?min. The scaling exponent obtained from the observed spectra has a value of about 2, which may be indicative of the physics of turbulence and raindrop coalescence and might suggest the predominance of a characteristic raindrop size. At 0.9?km resolution, the model rainfall spectra showed similar scaling to the observed down to about 10?min, below which a fall-off in variance was noted as compared to observations. Higher spatial resolution of up to 0.1?km was crucial to improve the ability of the model to resolve the shorter timescale variability. We suggest that the evaluation of dynamical models in the spectral domain is a crucial step in the validation of quantitative precipitation forecasts and assessing the minimal grid resolution necessary to capture rainfall variability for certain short timescales may be important for hydrological predictions.     

地级气象资料数据库建设模式

利用Microsoft Visual Studio 2005 （C#）及Microsoft SQL Server 2000编程建立地方级气象资料数据库,介绍了数据库的设计及所有功能,特别针对工作中的常规数据做了大量的工作。为了该数据库的方便使用,在设计时尽量避免冗余,创建了相应数据库表的关联,并使其发挥实用、高效之功能,从而实现了对大容量气象数据的现代化操作,大大提高工作效率,在很大程度上减少了工作量,使人们从繁重的手工操作中解脱出来。