We evaluated the performance of general atmosphere circulation model (GCM) from the European Center for Medium Range Weather Forecasts (ECMWF) for estimating surface air temperature (T) and precipitation (P) in 55 locations in the Brazilian Amazon. We compared data from surface meteorological stations obtained by the Brazilian Institute of Meteorology (INMET) and ECMWF by linear regression analysis (LRA) using R² and Willmott et al. (J Geophys Res C5:8995–9005,1985) index (d) as measurement of precision and accuracy, respectively. We applied the Fourier series analysis by extracting the trend and frequency components of P events with noise reduction in the time series. We used the multivariate K-means method to separate weather stations by Groups of Similar Performances (GSPs). The northwest region is characterized as the area with the highest precipitation supply but the lowest performances for T and P, with R² lower than 0.18. ECMWF tend to overestimate P in dry season and to underestimate in rainy season. The proposed methodology of calibration of P data by the Fourier series was a good tool to predict an extreme event every 5 to 7 months in the region. ECMWF presented high performance (R² > 0.60) when estimating P in a monthly scale and medium performance (R² < 0.60) when estimating T in a monthly and 10-day period. The highest concentrations of surface meteorological stations in the eastern/southeastern portion of the Amazon region were decisive in the ECMWF performance expression, indicating an increased meteorological predictability in the anthropic areas, precisely where the agricultural areas of grain were established in the region.

我们评估了欧洲中型天气预报中心（ECMWF）的一般大气环流模型（GCM）的性能，以估算巴西亚马逊地区55个地点的地表气温（T）和降水（P）。我们使用R ²和Willmott等人通过线性回归分析（LRA）比较了巴西气象研究所（INMET）和ECMWF从地面气象站获得的数据。（J Geophys Res C5：8995-9005,1985）指数（d）分别表示精密度和准确度。我们通过提取P的趋势和频率成分来应用傅里叶级数分析时间序列中的降噪事件。我们使用多元K均值方法按相似性能组（GSP）分隔气象站。西北地区的特点是降水量最多的地区，而T和P的表现最低，R ²低于0.18。ECMWF往往在干旱季节高估P，而在雨季低估。通过傅立叶级数提出的校准P数据的方法学是预测该地区每5至7个月发生一次极端事件的好工具。 估计P时ECMWF表现出较高的性能（R ² > 0.60）在每月和10天的时间段内 估算T时，按月规模和中等效果（R ² <0.60）进行评估。亚马逊地区东部/东南部地区地面气象站的最高浓度决定了ECMWF的表现，这表明人文地区（确切地说是该地区的谷物农业地区）的气象预报能力有所提高。