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作物产量气象预报服务方法 总被引:4,自引:0,他引:4
李新建 《沙漠与绿洲气象(新疆气象)》1997,20(4):50-53
作物收获前的适当时期发布作物产量预报,是气象部门气象决策服务及专业有偿服务重要的服务内容之一,成为政府领导及有关生产部门进行经济宏观调控、商贸部门进行商业贸易活动极为重要的决策依据。因此,作好作物产量预报服务具有很重要的作用和意义。1作物产量气象预报服务现程1.1作物产量气象预报类型目前作物产量预报分为4类:年景预报、趋势预报、定量预报、订正预报。年景预报:指作物尚未或即将播种时,利用一定范围的气象条件对该年度作物产量进行的一种长期预测。趋势预报:在作物收获前某个适宜发育时期,利用多种方法作出的当年… 相似文献
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水稻是贵州粮食作物中栽培面积最大。总产量最多、单产也最高的作物。建国以来,贵州水稻生产发展较快,总产量由1950年的211.1万吨增至1991年的428.7万吨,增长1倍多,但年际间的产量不稳定。产量波动主要受天气候条件尤以气象灾害影响最大。为此,必须掌握水稻栽培气象灾害发生的规律,采取相应对策与措施,才能减轻灾害造成的损失。本文分析了主要气象灾害对水稻的影响及其发生规律,提出了防灾减灾对策,对减轻灾害所造成的损失及促进水稻高产、稳产、优质、高效具有重要意义。1气象灾吝对水稻的影响1.1干旱1.1.旦春旱主要影响水稻… 相似文献
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对青海省8个农气观测站的草本植物物候期现象的变化及及其对气候变化响应的回归分析。结果表明:①草本植物自然物候现象存在着明显的地域性。②草本植物最初至最后的自然物候现象出现期呈现出作物生长季延长的趋势。③草本植物物候对气温的响应:上年10月至当年4月平均气温升高1℃,全省草本平均萌动期提早2.2d左右,平均展叶期提早3.9d;上年10月至当年9月平均气温升高1℃,平均黄枯期提早0.4d,萌动期至黄枯期平均间隔日数延长约4.5d,①草本植物物候对降水的响应:上年10月至当年4月降水量增多10mm,全省草本平均萌动期提早1.5d,平均展叶期提早0.9d;上年10月至当年9月降水量增多10mm,萌动期至黄枯期平均间隔日数缩短0.8d.(5)草本植物物候对日照的响应:各物候均不明显。 相似文献
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分析了2000年辽宁作物生长季的气候条件。对玉米、大豆、水稻等主要作物生长季的农业气象条件进行了评价:生长季内春季水热条件较好,对春播生产有利,作物生长良好;夏季降水量持续偏少,气温持续偏高,雨热同步性较差。大部分地区作物遭受历史罕见旱灾。 相似文献
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青海省土壤表面开始冻结和解冻期的变化对气候变化的响应及其应用 总被引:1,自引:0,他引:1
对青海省4个农气观测站的土壤表面开始冻结和解冻期现象的变化及其对气候变化响应进行回归分析。结果表明:1)因青海地形复杂而各地气象条件不同自然物候始冻结和解冻期存在着明显的地域性。2)最初至最后的自然物候现象出现呈现出作物生长季延长的趋势。3)全省土壤表面平均开始冻结期的响应:3—9月平均气温升高1℃,冻结推迟2.3d;3-9月总降水量增多10mm,冻结推迟0.4d。4)全省土壤表面平均开始解除冻期的响应:上年10月至当年2月平均气温升高1℃,解冻提早2.5d左右,上年10月至当年2月总降水量增多10mm,解冻推迟2.3d。全省土壤表面开始冻结至解冻平均间隔日数:上年10月至当年2月平均气温升高1℃,冻结至解冻平均间隔日数缩短1.8d;上年10月至当年2月总降水量增多10mm,则缩短6.7d。5)各地土壤表面开始冻结和解冻期自然物候在农林牧业生产中的具体应用还有待于进一步研究。 相似文献
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1993年五~3季度,我省频遭灾害性天气影响,市场几度出现菜少价高的现象。本文根据广州情况,从天气气候角度作简要分析。1气象原因蔬菜作物对气象条件变化反应较为敏感,多数经求温度i去中,_土壤水分充足。从温度而言,半耐“年蔬个作物多数为llJ某共和部分排菜类;喜温蔬菜作物主要是茄央关,部分瓜类和#类。半耐寒蔬菜作物的生K造温为]7~20(”,5~1)C也有~定的市长虽.SC以下则生长缓慢。喜温蔬菜作物生K的适宜温度为2(-3()C,在3O〔以上除瓜类m少数分类外。生k往往受到高温的抑制,九六件3IJ减弱。除水生蔬菜作物外。… 相似文献
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计算机的迅猛发展,给各学科注入了新的活力,也渗透到了农业这个古老的生产领域中,使农业气象研究中作物生长模拟由传统的静态模式发展到动态模式,各种作物发育动态的计算机模型先后问世,并投入到农业生产实践中。1研究回顾1.1积温学说1735年,法国人列奥默(Reaumur)“’创立了积温学说,一百年以后,鲍辛盖尔特(BOUSSlllgCCllt1837)称之为“度日法’,。后来引入了“临界温度”的概念,因此又有“有效积温”说,积温方法一直延用至今,是作物生育期预测的主要方法。积温法假设植物完成某一发育阶段所要求的平均温度的总和为一… 相似文献
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本文就朔州市2000年降水不多而粮食获得丰收,分析了年内4~9月光、热、水对农作物的利弊影响,提出了预报服务中应重视作物关键生育期的天气预报,以利于农业生产巧用天时,趋利避害,夺取丰收。 相似文献
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通过建立增产性能、稳产性能、重要性能、经济性能、抗旱性能 5个评价指标的隶属函数 ,运用模糊数学方法计算了武威市主要种植作物的气候经济优势 ,得出了在武威市目前社会、自然和经济条件下最具优势的 4种种植作物依次为玉米、甜菜、油菜和小麦。根据气候经济优势度值对现有种植结构提出了调整方案 相似文献
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该文概述了北半球和我国气候变暖中增温的非对称性特征:北半球气候变暖存在明显的季节差异和昼夜不同步性, 大部分地区冬、春季升温高于夏、秋季, 日最低气温升幅是日最高气温升幅的2~3倍; 近50年我国近地表气温升高主要是最低气温明显上升的结果, 日最低气温升幅是日最气高温升幅的2~3倍, 与北半球基本一致; 升温最显著的季节为冬季和春季。在此基础上概述了非对称性增温对农业生态系统的影响, 论述了非对称性增温对农作物物候和农作物产量的影响, 得出最低气温升高促使整个生长季延长, 促使早春作物物候期提前, 但最低气温和最高气温对不同作物的物候以及同一作物的不同发育阶段影响不同。现有研究多采用模型或统计的方法研究气候变暖对作物生长的影响, 认为温度升高对作物有“强迫成熟”效应; 而现有的最低气温升高和最高气温升高对作物生长影响的研究结果并不一致。非对称性增温对农作物影响的实验研究极少, 且缺乏对模型模拟结果的实验验证。 相似文献
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The effect of employing flux adjustments on the climatic response of an idealized coupled model to an imposed radiative forcing
is investigated with two coupled models, one of which employs flux adjustments. A linear reduction (to the planetary longwave
flux) of 4 W/m2 is applied over a 70 y period and held constant thereafter. Similar model responses are found (during the initial 70 y period)
for global-scale diagnostics of hemispheric air temperature due to the nearly linear surface-air temperature response to the
radiative forcing. Significant regional scale differences do exist, however. As the perturbation away from the present climate
grows, basin-scale diagnostics (such as meridional overturning rates) begin to diverge between flux adjusted and non-flux
adjusted models. Once the imposed radiative forcing is held constant, differences in global mean air temperature of up to
0.5 °C are found, with large regional-scale differences in air temperature and overturning rates within the North Atlantic
and Southern Ocean. Two additional experiments with the flux adjusted model (beginning from points further along the control
integration) suggest that the elimination of much of the coupling shock before the radiative forcing is applied leads to results
slightly closer to the non-flux adjusted case, although large differences still persist. In particular a dipole structure
indicating an enhanced warming within the Pacific sector of the Southern Ocean, and cooling within the Atlantic sector is
not reproduced by the flux adjusted models. This disparity is intimately linked to the Southern Ocean overturning cell along
with the flux adjustments employed as well as the drift arising from coupling shock. If a similar form of sensitivity exists
in more realistic coupled models, our results suggest: (1) perturbation experiments should not be undertaken until after the
coupled model control experiment is carried out for several hundred years (thereby minimizing the coupling shock); (2) care
should be exercised in the interpretation of regional-scale results (over the ocean) in coupled models which employ flux adjustments;
(3) care should also be taken in interpreting even global-scale diagnostics in flux adjusted models for large perturbations
about the present climate.
Received: 15 November 1996 / Accepted: 4 June 1997 相似文献
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Diana M. Liverman 《Climatic change》1987,11(1-2):267-285
This paper discusses the importance of testing models which may be used to forecast the impact of climate on society. Model testing using sensitivity analysis and validation techniques is illustrated with two models: (1) the YIELD model which simulates the impact of climate on crop yields of several major crops, and (2) the International Futures Simulation model which can be used to simulate the impact of crop yield changes on the world food system. The problems of linking such models to each other are also discussed. 相似文献
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Inconsistencies of precipitation in the eastern and central Tibetan Plateau between surface adjusted data and reanalysis 总被引:4,自引:1,他引:3
Qinglong You Klaus Fraedrich Guoyu Ren Baisheng Ye Xianhong Meng Shichang Kang 《Theoretical and Applied Climatology》2012,109(3-4):485-496
The Tibetan Plateau (TP) is the source of many Asian river systems and serves as “the Asian water tower”. Precipitation variability is a strong component of both hydrological processes and energy cycles, and the study of precipitation in the TP is of great importance in the content of global warming. In this study, the annual and seasonal (spring: MAM; summer: JJA; autumn: SON; and winter: DJF) variations in precipitation are investigated in the eastern and central TP during 1961–2007, based on surface raw and adjusted observations as well as both NCEP/NCAR (1961–2007) and ERA-40 (1961–2001) reanalyses. The adjusted precipitation in the TP is higher than raw values on both the annual and seasonal basis due to adjustments of solid precipitation by a bias experiential model. At the annual spring and winter scales, the adjusted precipitation shows a significant increase calculated by the Mann–Kendall trend test. Compared with adjusted precipitation; both NCEP/NCAR and ERA-40 reanalyses capture the broad spatial distributions of mean annual and seasonal precipitation, but are less good at repeating the decadal variability. Both reanalyses show the drying phenomena in most regions and fail to represent the change patterns of precipitation observed by the adjusted observations. Both NCEP/NCAR and ERA-40 have larger inconsistencies which may be caused by the differences between actual and model topography. This suggests that it is crucial to use the adjusted precipitation in the climate research and reanalysis products should be paid more attention in the TP. 相似文献