In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation r...In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation reanalysis product ERA-Interim in the period of 1979-2010. High correlations ranging from 0.973 to 0.999 indicate that ERA-Interim could capture the annual cycle very well. However, an average root-meansquare error(rmse) of 3.7°C for all stations reveals that ERA-Interim could not be applied directly for the individual sites. The biases can be mainly attributed to the altitude differences between ERA-Interim grid points and stations. An elevation correction method based on monthly lapse rates is limited to reduce the bias for all stations. Generally, ERA-Interim captured the Plateau-Wide annual and seasonal climatologies very well. The spatial variance is highly related to the topographic features of the TP. The temperature increases significantly(10°C- 15°C) from the western to the eastern Tibetan Plateau for all seasons, in particular during winter and summer. A significant warming trend(0.49°C/decade) is found over the entire Tibetan Plateau using station time series from 1979-2010. ERA-Interim captures the annual warming trend with an increase rate of 0.33°C /decade very well. The observation data and ERA-Interim data both showed the largest warming trends in winter with values of 0.67°C/decade and 0.41°C/decade, respectively. We conclude that in general ERA-Interim captures the temperature trends very well and ERA-Interim is reliable for climate change investigation over the Tibetan Plateau under the premise of cautious interpretation.展开更多
采用感官时间-强度法和高效液相色谱法对川渝地区7种青花椒原料的椒麻感官特征以及主要麻味物质组成及含量进行测定,并通过偏最小二乘回归(partial least squares regression,PLSR)对麻味物质组成含量及感官特性进行关联性分析。结果表...采用感官时间-强度法和高效液相色谱法对川渝地区7种青花椒原料的椒麻感官特征以及主要麻味物质组成及含量进行测定,并通过偏最小二乘回归(partial least squares regression,PLSR)对麻味物质组成含量及感官特性进行关联性分析。结果表明:青花椒的麻感具有先快速上升后缓慢下降的特征,100 s左右达到最大麻感强度。不同样品之间酰胺含量差异较大,含量分布范围为5505.77~8639.30 mg/100 g。PLSR结果表明青花椒麻感特性与酰胺物质组成关联密切,最大感官强度、持续时间(T_(tot))、曲线下面积与羟基-α-山椒素呈强正相关性,T_(tot)与羟基-ε-山椒素和羟基-β-山椒素呈强正相关性。不同产地青花椒在麻感特性和酰胺组成上存在差异,羟基-α-山椒素和花椒油素是不同青花椒样品麻感特性差异的关键物质。本研究旨在为后期川渝地区青花椒麻感品质评价提供基础数据参考和科学依据。展开更多
基金funded by Fujian Bureau of Surveying,Mapping and Geoinformation(Grant No.2013S17)Natural Science Foundation of China(Grant No.71373130)+2 种基金Non-Profit Research Projects of Fujian Province,China(Grant No2013R04)Key Project of the Department of Science and Technology of Fujian Province,China(Grant No.2012Y4001)supported by the ECMWF’s public web server(http://apps.ecmwf.int/datasets/)
文摘In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation reanalysis product ERA-Interim in the period of 1979-2010. High correlations ranging from 0.973 to 0.999 indicate that ERA-Interim could capture the annual cycle very well. However, an average root-meansquare error(rmse) of 3.7°C for all stations reveals that ERA-Interim could not be applied directly for the individual sites. The biases can be mainly attributed to the altitude differences between ERA-Interim grid points and stations. An elevation correction method based on monthly lapse rates is limited to reduce the bias for all stations. Generally, ERA-Interim captured the Plateau-Wide annual and seasonal climatologies very well. The spatial variance is highly related to the topographic features of the TP. The temperature increases significantly(10°C- 15°C) from the western to the eastern Tibetan Plateau for all seasons, in particular during winter and summer. A significant warming trend(0.49°C/decade) is found over the entire Tibetan Plateau using station time series from 1979-2010. ERA-Interim captures the annual warming trend with an increase rate of 0.33°C /decade very well. The observation data and ERA-Interim data both showed the largest warming trends in winter with values of 0.67°C/decade and 0.41°C/decade, respectively. We conclude that in general ERA-Interim captures the temperature trends very well and ERA-Interim is reliable for climate change investigation over the Tibetan Plateau under the premise of cautious interpretation.
