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青藏高原4月—10月光合有效量子值的气候学计算 总被引：4，自引：0，他引：4
根据１９９４年４月～１０月青藏高原太阳分光辐射的实测资料，计算出太阳总辐射中，光合有效辐射（ＰＡＲ）所占比例η＝０．４３９±０．００９，ＰＡＲ每１Ｊ的能量含有４．４３μｍｏｌ的量子。在青藏高原的气候学计算中，可用下式估算旬平均的ＰＡＲ能量日总量ＨＰＡＲ（ＭＪ·ｍ－２ｄ－１）和量子日总量ＵＰＡＲ（ｍｏｌ·ｍ－２ｄ－１）：ＨＰＡＲ＝（０．３９９＋０．０３６ｌｇＥ＊）ＨＵＰＡＲ＝（１．７６８＋０．１５９ｌｇＥ＊）Ｈ式中Ｈ（ＭＪ·ｍ－２ｄ－１）为总辐射旬平均日总量，Ｅ＊＝Ｅ·Ｐ０／Ｐ，Ｐ０（ｈｐａ）为标准大气压，Ｐ（ｈｐａ）为测点大气压，Ｅ（ｈｐａ）为地面水汽压。 相似文献
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研究了ＣＨＩＮＡＲＥ－６和ＣＨＩＮＡＲＥ－９普里兹湾内营养盐的分布及变化,采用化学质量平衡方法估计了该海区新生产力的大小。结果表明在ＣＨＩＮＡＲＥ－６期间,ＮＯ３－Ｎ、ＰＯ４－Ｐ、ＳｉＯ３－Ｓｉ消耗分别为１０６４．８、６９．２、２１９６．９ｍｍｏｌ／ｍ２,ＮＰ、ＳｉＰ吸收比分别为１５．３、３１．７,平均新生产力为９９２．４ｍｇＣ／（ｍ２ｄ）。在ＣＨＩＮＡＲＥ－９期间,ＮＯ３－Ｎ、ＰＯ４－Ｐ消耗分别为５５１．９、４１．２ｍｍｏｌ／ｍ２,ＮＰ吸收比为１３．４,平均新生产力３９０．１ｍｇＣ／（ｍ２ｄ）,表现出很大的季节和／或年际变化。估算的新生产力值都大于１４Ｃ测定的初级生产力值,表明普里兹湾海区夏季有很大的新生产力。元素吸收比和外海测定值不同,表明营养盐的吸收和循环在南极海区有很大的区域差异性。 相似文献
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本文测定了三元系ＲＥＣｌ３（ＲＥ＝Ｌａ，Ｐｒ，Ｓｍ）－ＨＯＡｃ－Ｈ２Ｏ（３０℃）的平衡态的溶度数据并绘制了相应的溶度图．在三个体系中分别形成ＬａＣｌ３·７Ｈ２Ｏ，ＰｒＣｌ３·６Ｈ２Ｏ，ＳｍＣｌ３·６Ｈ２Ｏ三种物质．ＨＯＡｃ对ＬｓＣｌ３·７Ｈ２Ｏ，ＰｒＣｌ３·６Ｈ２Ｏ，ＳｍＣｌ３·６Ｈ２Ｏ盐析作用程度的不同，表明了轻稀土元素的“一分组效应”，同时依据ＨＯＡｃ对ＬａＣｌ３·７Ｈ２Ｏ，ＰｒＣｌ３·６Ｈ２Ｏ，ＳｍＣｌ３·６Ｈ２Ｏ有盐折作用这一结论，提出了一种制备ＬａＣｌ３·７Ｈ２Ｏ，ＰｒＣｌ３·６Ｈ２Ｏ，ＳｍＣｌ３·６Ｈ２Ｏ的新方法． 相似文献
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研究了不同浓度ＭｇＣｌ２（１．９９８、３．８６７、５．７３５％）溶液，在不同温度（２５、５５℃）下，对软钾镁矾在Ｋ＋，Ｍｇ２＋／ＳＯ_４￣２－，Ｃｌ－Ｈ２Ｏ四元体系中溶解转化过程的影响，采用龙格－库塔微分数值法拟合其溶解过程和结晶过程动力学方程。结果表明在一定浓度ＭｇＣｌ２溶液中软钾镁矾是不相称溶解，Ｋ２ＳＯ４先于ＭｇＳＯ４溶解进入溶液中，ＭｇＣｌ２溶液浓度越大，温度越高，溶解速度越快，Ｋ２ＳＯ４结晶速度也越快．溶解受扩散和表面反应控制，Ｋ２ＳＯ４结晶受扩散控制． 相似文献
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云南大理点苍山地区更新世晚期沉积地层的ESR测所研究 总被引：1，自引：0，他引：1
本文采用电子自旋共振（ＥＳＲ）方法测定了云南点苍山地区更新世晚期沉积地层的形成年代。测年结果显示：（１）点苍山地区冰川沉积物的ＥＳＲ年龄均小于１４０．３５ＫａＢＰ．，说明该地区的第四纪冰川作用最早出现于中更新世晚期，主要发生于晚更新世；（２）点苍山西麓平坡附近最高一级基座阶地的堆积时代为１８４．３ＫａＢＰ．，证明西洱河阶地系列为中更新世以来的产物；（３）点苍山东侧白雀寺地区深３．７ｍ处的褐红色地层 相似文献
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气象要素空间插值方法优化 总被引：86，自引：8，他引：78
在区域水土平衡模型的研究中 ,空间插值可提供每个计算栅格的气象要素资料。本文运用反距离加权法 (IDW )和梯度距离反比法 (GIDW ) ,对 196 1～ 2 0 0 0年甘肃省及其周围85个气象站点的多年平均温度与降雨量进行了内插。交叉验证结果表明 :对于IDW和GIDW ,二者温度插值的平均绝对误差 (MAE)分别为 2 2 8℃和 0 73℃ ,平均相对误差(MRE)分别为 2 9 0 2 %和 9 4 1% ,降雨插值的MAE值依次为 5 5 2mm和 4 90mm ,MRE值分别为 19 4 3%和 17 80 % ,GIDW明显优于IDW。需要指出的是 :对于降雨 ,当其经纬度和海拔高程的复相关系数大于 0 80时 ,GIDW插值结果优于IDW ;否则相反 相似文献
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基于DEM的中国陆地多年平均温度插值方法 总被引：53，自引：2，他引：53
以1961~2000年全国726个气象站点旬平均温度为基础数据,在分析了多年月平均温度和年平均温度的空间分布与经度、纬度、高度的内在关系后,提出了一种基于DEM和智能搜索距离的温度空间插值方法(SSI),并与反距离平方(IDS) 等传统方法进行了对比。交叉验证结果表明:1) 传统的IDS方法最优结果的MAE范围是1.44 oC~1.63 oC,平均1.510C;而SSI温度插值方法的平均绝对误差为0.53 oC~0.92 oC,平均值0.69 oC,精度超过IDS等方法一倍以上。2) 随着距离的增大,站点间温度的相关性逐渐降低,会降低估算精度;小于一定的搜索半径,被估算点周围的相邻站点的数目逐渐减少,同样会降低插值的精度,因而对中国陆地部分温度插值而言,最优的空间插值搜索半径介于150~250 km之间。最后,结合DEM数据,生成了0.1o ×0.1o中国陆地区域多年月平均和年平均温度栅格图像数据集,该结果表明:利用SSI方法不仅可以生成高精度、高空间分辨率的网格温度结果,而且其插值结果能客观细致的反映温度随经度、纬度和高度梯度变化的地带性特征。 相似文献
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长江口滨岸湿地无机氮界面交换通量量算 总被引：1，自引：0，他引：1
基于3年长江口滨岸湿地沉积物－水界面无机氮季节性交换通量连续实测数据,建立无机氮界面交换通量空间插值模型与量算模型,对无机氮界面交换通量季节性空间分布特征、滨岸湿地不同岸段无机氮季节性界面交换总通量量算等研究。结果表明：修正GIDS插值模型在无机氮界面交换通量空间插值预测过程中精度明显优于IDS方法,而略优于普通Kriging方法;长江口滨岸湿地沉积物－水界面无机氮交换通量空间分布在不同季节表现出复杂的空间分异特征;利用修正GIDS插值模型对长江口滨岸湿地无机氮交换通量进行空间插值过程中,为提高通量量算模型精度,应采用1.2'×1.2'的空间尺度为最佳;长江口滨岸湿地无机氮界面交换总通量量算表明,长江口滨岸湿地在春季向水体释放无机氮,是水体无机氮的释放源,释放量为1.33×104 t,夏季、秋季和冬季表现为净化水体中无机氮,是水体无机氮的吸收汇,分别净化无机氮量为4.36×104 t、6.81×104 t和2.24×104 t,全年总体表现为净化水体中无机氮,净化量为12.1×104 t;长江口多年水体中无机氮通量多项式拟合分析得出,2002~2004年3年长江口水体中无机氮通量平均值为52.6×104 t,滨岸湿地对长江口水体中无机氮的年均净化率达23.0%。 相似文献
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基于GIS的农业气候资源区域化问题研究——以甘肃省为例 总被引：10，自引：1，他引：9
在农业气候资源研究中,站点数据的区域化问题是进行资源优化配置和高效利用的一个重要环节。通过采用逐步回归分析与空间插值相结合的方法,以甘肃省及其相邻省区的112个站点1970~2001年31年的月平均温度和降水数据以及计算得到的月平均太阳辐射和潜在蒸散量为数据源,对甘肃省气候资源进行了区域化。对每种气象要素都采用了两种空间插值方法,并对插值结果运用了绝对验证和相对验证两种方法进行了验证和对比。结果表明:温度残差的平均绝对误差(MAE)是Spline< IDW, 其值分别为:0.744℃和0.754℃,平均相对误差(RME)分别为:9.56%和9.66%。降水的平均绝对误差是Kriging温度>潜在蒸散量>降水,但都达到了较高的精度。 相似文献
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《自然地理学》2013,34(6):517-527
Short-term monthly mean temperature (Tm ) and short-term daily mean temperature (Td ) rather than long-term monthly and daily mean temperature (Tm and Td ) are preferred for some ecosystem studies such as carbon source and sink, pine beetle mortality, and snow melting. The recent progress of modeling Tm and Td (based on the previous work on Tm ) supported by climatologically aided interpolation (CAI) is reported over the mountainous Yellowstone National Park. With the spatial scale of a 30 m digital elevation model (DEM), the slope, aspect, and shadows cast by surrounding topography, which could not be well captured by very coarse DEM, could be taken into account. Data from 12 months (Jan-Dec 2008) and 12 dates (25 Jan-Dec 2008) were used to demonstrate the approach. Inverse distance weighting (IDW) interpolations of limited temperature anomalies were adopted to represent the deviations from normality. Tm , as a preexisting climatology surface, was added to deviations in order to model Tm . Linear temporal interpolation of adjacent Tm was used to create a climatology surface, which was then added to deviations in order to model Td . Results show the mean absolute errors (MAEs) for Tm ranged from 0.75° C to 1.78° C, while the MAEs for Td ranged from 1.14° C to 2.02° C. The four factors of elevation, seasonal change of lapse rate, temperature difference caused by variation in solar radiation, and preexisting climatology surface for the CAI approach were comprehensively considered in this approach. 相似文献
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川渝地区气温随地形、经度和纬度的变化(英文) 总被引：4，自引：1，他引：3
Using the daily temperature data of 95 meteorological stations from Si-chuan-Chongqing Region and its surrounding areas, this paper adopted these methods (e.g., linear regression, trend coefficient, geographical statistics, gray relational analysis and spatial analysis functions of GIS) to analyze the relations of temperature variability with topography, latitude and longitude. Moreover, the rank of gray correlation between temperature variability and elevation, longitude, latitude, topographic position and surface roughness also was measured. These results indicated: (1) The elevation affected temperature variability most obviously, followed by latitude, and longitude. The slope of the linear regression between temperature change rate and elevation, latitude and longitude was 0.4142, 0.0293 and -0.3270, respectively. (2) The rank of gray correlation between temperature change rate and geographic factors was elevation > latitude > surface roughness > topographic position > longitude. The gray correla-tion degree between temperature change rate and elevation was 0.865, followed by latitude with 0.796, and longitude with 0.671. (3) The rate of temperature change enhanced with the increase of elevation. Especially, the warming trend was significant in the plateau and mountain areas of western Sichuan, and mountain and valley areas of southwestern Sichuan (with the warming rate of 0.74℃/10a during the 1990s). However, there was a weak warming trend in Sichuan Basin and its surrounding low mountain and hilly areas. (4) The effects of latitude on temperature change rate presented the specific regulation, which the warming rate of low-latitude areas was more significant than that of high-latitude areas. However, they were consistent with the regulation that the increasing of low temperature controlled most of the warming trend, due to the effects of terrain and elevation on annual mean temperature. (5) Ba-sically, temperature variability along longitude direction resulted from the regular change of elevation along longitude. It was suggested that, in Sichuan-Chongqing Region, special features of temperature variability largely depended on the terrain complexity (e.g., undulations, mutations and roughness). The elevation level controlled only high or low annual mean temperature and the range of temperature change rate in the macro sense. 相似文献
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DELIANG CHEN LEBING GONG CHONG-YU XU SVEN HALLDIN 《Geografiska Annaler: Series A, Physical Geography》2007,89(4):249-261
A baseline climatology is required in evaluating climate variability and changes on regional and local scales. Gridded climate normals, i.e. averages over a 30‐year period, are of special interest since they can be readily used for validation of climate models. This study is aimed at creating an updated gridded dataset for Swedish monthly temperature normals over the period 1971–2000, based on standard 2‐m air temperature records at 510 stations in mainland Sweden. Spatial trends of the normal temperatures were modelled as functions of latitude, longitude and elevation by multiple linear regression. The study shows that the temperature normals are strongly correlated with latitude throughout the year and especially in cold months, while elevation was a more important factor in June and July. Longitude played a minor role and was only significant in April and May. Regression equations linking temperature to latitude, longitude and elevation were set up for each month. Monthly temperature normals were detrended by subtracting spatial trends given by the regressions. Ordinary kriging was then applied to both original data (simple method) and de‐trended data (composite method) to model the spatial variability and to perform spatial gridding. The multiple regressions showed that between 82% (summer) and 96% (winter) of the variance in monthly temperature normals could be explained by latitude and elevation. Unexplained variances, i.e. the residuals, were modelled with ordinary kriging with exponential semivariograms. The composite grid estimates were calculated by adding the multiple linear trends back to the interpolated residuals at each grid point. Kriged original temperature normals provided a performance benchmark. The cross–validation shows that the interpolation errors of the normals are significantly reduced if the composite method rather than the simple one was used. A gridded monthly dataset with 30‐arcsecond spacing was created using the established trends, the kriging model and a digital topographic dataset. 相似文献
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近50年来中国冬季风寒温度的变化 总被引：4，自引：0，他引：4
风寒温度是冬季表征人体热舒适度常用的参数,也是气候变化影响研究中关注的要素。本文利用中国地面国际交换站气候资料月值数据集的气温和风速,分析1956-2005年中国冬季风寒温度的时间和空间变化特征。结果表明,近50年来中国冬季风寒温度普遍呈上升趋势,全国平均升高3.2 oC,变化速率达0.64 oC/10a;西北、华北、东北和青藏地区的上升速率分别为0.79 oC/10a、0.84 oC/10a、0.81 oC/10a、0.80 oC/10a,其中华北北部农牧交错带地区上升趋势最为强烈,超过1 oC/10a;35oN以南的我国南方地区上升速率较低,为0.39 oC/10a。风寒温度的这种变化特征是近50年来气温升高和风速下降综合作用的结果。其中气温变化造成的风寒温度上升是2.4 oC,而地表风速下降对风寒温度的贡献为0.8 oC。东亚气温和风速的变化受诸多大气环流系统的影响,分析表明影响东亚气候的几个主要环流因子中,西伯利亚高压、北极涛动、西太平洋遥相关型和欧亚遥相关型等与风寒温度有显著相关。这四个环流因子一起能解释50年来全国平均风寒温度方差的46.7%。全国平均气温与这四个环流因子的相关分别达到-0.65,+0.49,+0.31和-0.32;而平均风速与北极涛动的相关最显著,达-0.51。 相似文献
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当前气温插值方法多将高程、经纬度等作为影响因素,无法解决风向、风速对气温空间分布的影响问题。该文提出一种顾及风向和风速的气温空间插值方法:1)根据气象观测站点的风向、风速数据进行插值,生成连续的风场表面;2)基于该风场数据利用高斯扩散模型构建成本表面;3)利用Dijkstra最短路径算法计算观测点与待求点的累计移动成本最短路径(SPOCMC);4)将SPOCMC作为协变量进行薄盘光滑样条插值以实现气温插值。为验证该方法的有效性和可靠性,选取山东省109个气象观测点样本数据,以SPOCMC、DEM和SPOCMC-DEM分别作为协变量对气温数据进行薄盘光滑样条插值,结果显示:SPOCMC-DEM法的MAE和RMSE均值(分别为0.517、0.779)略低于SPOCMC法(0.583、1.016),显著低于DEM法(0.809、1.231),表明添加SPOCMC作为协变量可有效提高气温空间插值的准确性。在江苏省与贵州省的插值实验结果证明了该方法的普适性。 相似文献
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薄板光顺样条插值与中国气候空间模拟 总被引：27，自引：0，他引：27
利用720个气象台网的长期平均气象数据拟合具有三维地理空间的气候曲面,并与1km空间分辨率的数字高程模型相结合,对气候变量的规则栅格进行插值估计。对各月平均最低温度、平均最高温度和降水量的插值结果构成了基础数字气候空间,以满足地理信息系统的数据分析需求。插值过程提供的误差统计表明插值的温度误差普遍小于0.6度,降水误差范围在8%~15%,明显优于其它插值方法。样条法利用线性模型反映地形对气候的影响,并提供了简便的误差诊断程序,具有良好的实用性。 相似文献