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1.
The objective of the present study was to use the simple cokriging methodology to characterize the spatial variability of Penman–Monteith reference evapotranspiration and Thornthwaite potential evapotranspiration methods based on Moderate Resolution Imaging Spetroradiometer (MODIS) global evapotranspiration products and high-resolution surfaces of WordClim temperature and precipitation data. The climatic element data referred to 39 National Institute of Meteorology climatic stations located in Minas Gerais state, Brazil and surrounding states. The use of geostatistics and simple cokriging technique enabled the characterization of the spatial variability of the evapotranspiration providing uncertainty information on the spatial prediction pattern. Evapotranspiration and precipitation surfaces were implemented for the climatic classification in Minas Gerais. Multivariate geostatistical determined improvements of evapotranspiration spatial information. The regions in the south of Minas Gerais derived from the moisture index estimated with the MODIS evapotranspiration (2000–2010), presented divergence of humid conditions when compared to the moisture index derived from the simple kriged and cokriged evapotranspiration (1961–1990), indicating climate change in this region. There was stronger pattern of crossed covariance between evapotranspiration and precipitation rather than temperature, indicating that trends in precipitation could be one of the main external drivers of the evapotranspiration in Minas Gerais state, Brazil.  相似文献   

2.
基于GIS的赤水市金钗石斛农业气候区划   总被引:4,自引:0,他引:4  
石斛是热带、亚热带丛生植物,喜温暖湿润气候。赤水市是我国目前金钗石斛最大和最适宜种植区。根据赤水市气候资源特点及金钗石斛适宜生长环境指标,选取了年平均气温、全年≥10℃活动积温、海拔高度、月平均气温≥25.0℃月数、分蘖开花期(3-5月)空气相对湿度等5个气象因子作为种植区划指标,在综合考虑经度、纬度和海拔高度对气候资源影响的基础上,利用遵义市12个气象站1971-2000年气候资料和台站信息,采用逐步回归法分别构建了4个区划因子的细网格推算模型。基于数字高程(DEM)数据推算了分辨率为1 km的赤水市气候资源数据集。利用赋值法对5个区划指标分别计算,按照适宜种植区、次适宜种植区和不适宜种植区3个等级完成了赤水市金钗石斛种植气候区划。区划结果显示,赤水市金钗石斛的适宜种植区随地形和海拔高度而变化,主要分布在沿赤水河两岸和沿习水河两岸的沟谷或山地。次适宜和不适宜区主要分布在海拔700 m以上的半高山地区,冬季气温偏低、热量供应不足和夏秋干旱是这些区域不适宜种植的主要原因。  相似文献   

3.
In this study, regression equations to estimate the monthly and annual values of the mean maximum and mean minimum air temperatures in Greece are derived. For this purpose, data from 87 meteorological stations distributed all over Greece are used. Geographical parameters, i.e., altitude, latitude, longitude, minimum distance from the sea and an index of terrain morphology, are used as independent variables. These equations explain 79?C97% of the variance of the temperature values and have standard error of estimate between 0.59 and 1.20°C. Data from 37 other meteorological stations are used to validate the accuracy of the equations. Topographic or climatic factors, which could not be introduced into the equations, are responsible for most temperature residuals >0.5°C or <?0.5°C. Moreover, some particular emphasis has been given to the values of the regression coefficient for the altitude, since it is the estimator for the mean lapse rate of air temperature.  相似文献   

4.
The knowledge of the climatic conditions of a region is crucial for its agricultural development. It is also extremely important for understanding the fact that certain cultures have to develop under prevailing temperature and humidity conditions and assist in the adoption of a suitable irrigation technique, as well as its management and operationalization. The K?ppen system of climate classification is widely used for the identification of homogeneous climate zones as it considers only rainfall and temperature as the meteorological elements for classification. For this study, we used climatic databases of rainfall and temperature in a raster format, with a spatial resolution of 30″ of arc (an approximate area of 0.86?km2?pixel?1), from 1961 to 1990. Through geoprocessing techniques, we obtained a map of climatic classification for the state of Minas Gerais. We found that the state has the following three major climatic groups: A, B and C, which correspond to tropical rainy, dry and warm temperate climates, respectively. The climate classes obtained were Aw, Am, BSh, Cwa and Cwb, with Aw, Cwa and Cwb classes occupying 99.89% of the territorial area of the state. The validation of the results showed a satisfactory agreement, with 93.75% reliability.  相似文献   

5.
利用柴达木盆地11个国家气象站(2017年3月—2018年2月)及28个区域气象站(2017年6—8月)月降水量资料,运用线性回归订正法和比值订正法推算柴达木盆地的年降水量,进一步分析柴达木盆地降水量季节变化及空间分布特征。结果表明:(1)柴达木盆地降水量年内分配极不均匀,呈单峰性,峰值出现在7月,5—9月(汛期)降水量占全年的87.4%。季节差异非常明显,降水主要集中在夏季;(2)年降水量空间分布特征:柴达木盆地年降水量各地差异极为显著,降水量整体表现为从东向西逐渐减少。最大值出现在天峻,最小值出现在冷湖。用2种方法推算的年降水量最大值出现在柴达木盆地东北部祁连山南麓的木里镇,其次在格尔木市南部出现了两个相对的大值中心,中间区域(93°~97°E)由四周山区向盆地中心逐渐减少的形势表现得更加清晰。夏季降水量的空间分布与年降水量的空间分布完全一致。(3)国家气象站模型中降水量分布只受经度和海拔高度的影响,而线性回归法和比值订正法模型中降水量的分布不仅受经度和海拔高度的影响,还受纬度的影响,三者的贡献率由大到小的排序是经度海拔高度纬度。  相似文献   

6.
自动气象站位置信息是准确应用观测数据的前提,但受多种因素影响部分测站位置信息不准确客观存在。依据气象站位置信息的特点,设计了一套适用于观测数据中气象站位置信息检验评估的方法和流程,对2018年1月全国62 162个气象站逐小时观测数据中经纬度和海拔高度进行了检验。结果表明:(1)位置信息出现疑误的站点均为区域站;(2)位置信息的站点疑误率为4. 8%,且海拔高度出现疑误的概率大于经纬度,海拔高度和经纬度的站点疑误率分别为4. 2%和1. 3%;(3)随时间变化异常是位置信息疑误的主要表现形式,经纬度和海拔高度时间一致性检查的方法检出率分别为94. 9%和74. 5%。最后,依托MDOS建立了自动气象站位置信息综合监视流程,降低了位置信息疑误对后端应用的影响。  相似文献   

7.
针对内蒙古自治区巴彦淖尔市气象站点分布情况,以2000—2009年9个气象站点(临河,杭锦后旗,五原,磴口,乌拉特前、中、后三旗,海力素,大佘太)的年平均降水和温度为基础数据,通过GIS空间分析中的空间数据插值方法,分别建立平均降水和温度与海拔、经纬度之间的回归方程;在此基础上,建立模拟站点来增加气象数据的信息量。分别采用反距离加权法、径向基函数法、趋势面分析和普通克里格法几种插值方法进行比较插值分析。误差分析表明没有绝对最优的空间插值方法,只有在特定的条件下的最有效方法,对于降水量插值来说三次样条小波插值法是最好的;比较分析的结果表明,模拟站点的加入大大提高了插值的精度,普通克里格法比反距离加权法和径向基函数法具有更为理想的插值效果;并据此理论分析对空间插值在冬季高速公路养护方面的应用问题进行阐述。  相似文献   

8.
黑龙江省延迟型低温冷害气候指标研究   总被引:2,自引:0,他引:2  
针对影响黑龙江省农业生产的延迟型低温冷害,探讨前人提出的东北地区低温冷害气候指标在黑龙江省的适用性,借鉴前人经验,考虑玉米和水稻种植面积不断北扩等因素,确定黑龙江省延迟型性低温冷害气候指标的技术路线、判识临界值和计算方案。利用1961-2012年黑龙江省27个气象台站5-9月平均气温,以热量指数距平冷害判识指标为参照,考虑低温冷害指标与纬度、经度和海拔高度的密切关系,采用逐步回归法建立黑龙江省延迟型低温冷害气候指标;经过验证,表明该指标判识的低温冷害年与黑龙江省低温冷害的实际和发生规律相符,可作为监测指标;该指标所需数据量小,计算简便,具有实用性和推广价值;可采用该指标对黑龙江省低温冷害的历史发生规律进行分析。  相似文献   

9.
Modeling monthly mean air temperature for Brazil   总被引:1,自引:1,他引:0  
Air temperature is one of the main weather variables influencing agriculture around the world. Its availability, however, is a concern, mainly in Brazil where the weather stations are more concentrated on the coastal regions of the country. Therefore, the present study had as an objective to develop models for estimating monthly and annual mean air temperature for the Brazilian territory using multiple regression and geographic information system techniques. Temperature data from 2,400 stations distributed across the Brazilian territory were used, 1,800 to develop the equations and 600 for validating them, as well as their geographical coordinates and altitude as independent variables for the models. A total of 39 models were developed, relating the dependent variables maximum, mean, and minimum air temperatures (monthly and annual) to the independent variables latitude, longitude, altitude, and their combinations. All regression models were statistically significant (α?≤?0.01). The monthly and annual temperature models presented determination coefficients between 0.54 and 0.96. We obtained an overall spatial correlation higher than 0.9 between the models proposed and the 16 major models already published for some Brazilian regions, considering a total of 3.67?×?108?pixels evaluated. Our national temperature models are recommended to predict air temperature in all Brazilian territories.  相似文献   

10.
Future climate change is expected to have many impacts on forest ecosystems. It is important to have some understanding of these impacts in order to make informed forest management decisions. A major consideration in making forest management decisions is the productivity of a site, as measured by site index. In this study, I relate Douglas-fir site index to accumulated growing degree-days greater than 5°C (DD5), as well as to soil moisture and nutrient regime. This allows the impact of climate change on forest productivity to be estimated. A two step approach was followed. The first step derived models to estimate various climate variables to latitude, longitude, and elevation using data from climate stations. Then, these climate variables were used along with soil moisture and nutrient data to predict site index for the site index plots. A two step approach was taken because climatic data were not available for the site index plots. The trend was for site index to increase with both increasing soil moisture and nutrients, although the site index decreased on the wetter sites. Site index also increased with DD5 at the rate of 1.2 m for every increase of 100 units in DD5. These models can be used together to evaluate the impact of various climate change scenarios on site index.  相似文献   

11.
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   

12.
Summary Using a dense network of carefully tested and homogenized long-term temperature and precipitation data this paper describes climatic variations during the last 150 years for both these important climatic elements. It turned out that the response of precipitation to climate warming is quite different within a small region, of 7 degrees longitude by 2 degrees latitude. In the western parts of Austria an increase of warm and wet climate has occurred, whereas during the same period in the East an increase of warm and dry conditions has occurred. An even larger variety of spatially different trends appears concerning seasonal evolution. The question of climate change cannot be answered in the same way when taking into account larger regions and not only temperature but also other climatic elements.With 9 Figures  相似文献   

13.
近38年中国气温和降水的1 km网格数据集   总被引:1,自引:0,他引:1  
对中国38年的气温和降水进行了空间插值分析,选取最优模型去生成1km网格数据集,为中国大陆的植被分布、气候变化和环境生态等研究提供支持。基于国家气象中心839个气象站的逐日气温和降水数据,用经度、纬度和海拔作为ANUSPLIN软件插值的3个变量,对降水进行开平方预处理,采用3次样条的薄盘光滑样条法,得到了1980—2017年中国大陆月平均气温和月累计降水1km网格插值数据集。数据集的广义交叉验证均方根(RTGCV)和均方根误差(RMSE)具有年周期性和明显的季节变化特征;各站点的平均误差(MBE)的频率分布近似正态分布,绝对误差(MAE)的空间分布也符合中国大陆气候的变化特征。数据集在精准度和时间序列上较新,且提供公共下载服务,可为全国陆地生态系统的研究提供信息支持。  相似文献   

14.
Climate is an important resource for many types of tourism. One of several metrics for the suitability of climate for sightseeing is Mieczkowski’s “Tourism Climatic Index” (TCI), which summarizes and combines seven climate variables. By means of the TCI, we analyse the present climate resources for tourism in Europe and projected changes under future climate change. We use daily data from five regional climate models and compare the reference period 1961–1990 to the A2 scenario in 2071–2100. A comparison of the TCI based on reanalysis data and model simulations for the reference period shows that current regional climate models capture the important climatic patterns. Currently, climate resources are best in Southern Europe and deteriorate with increasing latitude and altitude. With climate change the latitudinal band of favourable climate is projected to shift northward improving climate resources in Northern and Central Europe in most seasons. Southern Europe’s suitability for sightseeing tourism drops strikingly in the summer holiday months but is partially compensated by considerable improvements between October and April.  相似文献   

15.
The spatial distribution of long-term average air freezing and thawing indices in Yakutia was investigated using the data of 156 meteorological stations located in this region. The regularities of variations of air freezing and thawing indices are revealed depending on the impact of zonal, regional, and local environmental factors. The concrete correlations with the latitude, longitude, and altitude are obtained. The effects of climatic processes and relief of regional and local levels are estimated. Based on the revealed relationships, the 1 : 5000000-scale maps are plotted to demonstrate the spatial variations of air freezing and thawing indices.  相似文献   

16.
为合理利用吉林市气候资源,提升烤烟生产效益,开展烤烟栽培气候适宜性定量评估,以制定烤烟种植优化调整方案。采用烤烟产量、气象和海拔高程等数据,基于气象条件对当地烤烟的影响,以及烤烟栽培气候资源供求关系,确定影响烤烟栽培的气象要素。采取模糊数学方法建立吉林市烤烟适宜度隶属函数及综合评价模型。考虑到海拔高度和经纬度与气象条件的关系,建立吉林山区诸气象要素的地理分布模式,在GIS平台下实现吉林市烤烟种植适宜度的精细化气候区划。结果表明:吉林市大部分地方都比较适宜烤烟栽培,但气候适宜度存在明显的区域差异,可划分为最适宜区、适宜区、次适宜区、不适宜区4类。研究区域东部和南部海拔500-800 m左右的中山地带适合烤烟栽培,但其中海拔800 m以上的高山地带气温过低,不适宜烤烟栽培;西部半山-平原区适宜度并不高。蛟河市适宜烤烟种植面积最大,其次是桦甸市,磐石市和舒兰市也较适宜烤烟栽培。烤烟精细区划结果与当地多年烤烟种植区域有一致性,但仍有较大的优化调整空间和增产增收潜力。  相似文献   

17.
近50a中国降水格点数据集的建立及质量评估   总被引:11,自引:2,他引:9  
赵煜飞  朱江  许艳 《气象科学》2014,34(4):414-420
基于2012年6月更新的高质量2 400个台站降水资料,采用薄盘样条法,制定了采用3个自变量(经度、纬度、海拔高度)、降水量开平方预处理、3次样条的插值方案,并引入数字高程资料,以减弱中国独特地形条件下高程对降水空间插值精度的影响,并对1961—2010年中国区域地面降水站点资料进行了空间内插,得到了中国地面降水0.5°×0.5°格点数据集。经数据集的质量评估结果表明:分析值与站点观测值均方根误差平均为0.49 mm,相关系数平均达0.93(通过0.01的显著性检验),夏季插值误差高于冬季,东南地区误差普遍高于其他地区。冬、春、夏、秋季绝大多数台站绝对误差在±10 mm/月以内。冬、春、夏、秋季分别有60%、82%、54%、77%的台站相对误差在±10%之间。插值后的格点化降水资料能够比较细致、准确地描述中国大陆年平均降水场的东南多、西北少的主要空间特征,但也平滑掉了范围很小的降水极值中心。台站分布越密集的地方,插值效果越好,并且最近距离小于40 km的台站插值精度较高,大于40 km插值精度衰减较快。  相似文献   

18.
针对开展乡镇天气预报时对高精度逐日气象要素输入值的需要,以辽宁地区为例, 在乡镇预报前期研究成果的基础上,选用距离权重反比法作为基本方法,综合考虑海拔高度,建立风向、风速、相对湿度和云量历史资料库。结果表明:风速、相对湿度可由经度和纬度求算权重,然后采用海拔高度订正插值误差最小;风向和云量可由经度、纬度和海拔高度求算空间距离确定权重插值误差最小。  相似文献   

19.
This study identifies possible hotspots of climate change in South America through an examination of the spatial pattern of the Regional Climate Change Index (RCCI) over the region by the end of the twenty-first century. The RCCI is a qualitative index that can synthesize a large number of climate model projections, and it is suitable for identifying those regions where climate change could be more pronounced in a warmer climate. The reliability and uncertainties of the results are evaluated by using numerous state-of-the-art general circulation models (GCMs) and forcing scenarios from the Coupled Model Intercomparison Project phases 3 and 5. The results show that southern Amazonia and the central-western region and western portion of Minas Gerais state in Brazil are persistent climate change hotspots through different forcing scenarios and GCM datasets. In general, as the scenarios vary from low- to high-level forcing, the area of high values of RCCI increase and the magnitude intensify from central-western and southeast Brazil to northwest South America. In general, the climatic hotspots identified in this study are characterized by an increase of mean surface air temperature, mainly in the austral winter; by an increase of interannual temperature variability, predominantly in the austral summer; and by a change in the mean and interannual variability of precipitation during the austral winter.  相似文献   

20.
Brazil suffers yearly from extreme weather and climate events, which can be exacerbated in a warmer climate. Although several studies have analyzed the projections of climate change in Brazil, little attention has been paid to defining the locations that can be most affected, and consequently have a more vulnerable population, in a spatially-explicit form. This study presents a spatial analysis of summarized climate change data and a joint investigation combining these possible climate changes and social vulnerability indicators in Brazil. The Regional Climate Change Index (RCCI), which can synthesize a large number of climate model projections, is used for the climate analysis, and the Socio-Climatic Vulnerability Index (SCVI) is proposed to aggregate local population vulnerabilities to the climate change information. The RCCI results show climatic hotspots emerging in Brazil, covering the western portion of the Northeast (NE), northwestern Minas Gerais state and center-western (CW) and northern regions (N), except northeast Pará and Amapá states. The SCVI analysis reveals major socio-climatic hotspots in the NE and several localized hotspots in some of the major Brazilian metropolitan regions, namely Manaus, Belo Horizonte, Brasília, Salvador, Rio de Janeiro and S?o Paulo. The two novelties of this study are a spatially detailed analysis of the RCCI in Brazil and the development of an index that can summarize the large amount of climate model information available today with social vulnerability indicators. Both indices may be important tools for improving the dialogue between climate and social scientists and for communicating climate change to policymakers in a more synthetic and socially relevant form.  相似文献   

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