A vegetation phenology dataset by integrating multiple sources using the Reliability Ensemble Averaging method

A vegetation phenology dataset for the Northern Hemisphere( the latitude ranging from 30°N to 90°N, the longitude ranging from -180°E to 180°E), including start of season (SOS_merge), SOS uncertainty range (SOS_merge_r), end of season (EOS_merge), and EOS uncertainty range (EOS_merge_r). This dataset is generated by merging four vegetation phenology datasets including MODIS MCD12Q2(https://lpdaac.usgs.gov/products/mcd12q2v061/), MEaSUREs VIPPHEN(https://lpdaac.usgs.gov/products/vipphen_ndviv004/), GIMMS NDVI3g(http://data.globalecology.unh.edu/data/GIMMS_NDVI3g_Phenology/), GIMMS NDVI4g(https://doi.org/10.5281/zenodo.7649107) using the reliability ensemble averaging method. The uncertainty range is calculated based on the weight of each dataset and the deviation between REA result and data sources, the upper and lower uncertainty limits are measured by REA result and the uncertainty range. The spatial resolution of the new dataset is 0.05° and its temporal scale spans 1982–2022. The new dataset was validated using data from the ground-based PhenoCam dataset from 280 sites over the period 2000–2018, which provided 1410 site–year combinations. The dataset is stored in TIFF format, the unit of “SOS_merge” and “EOS_merge” is day of year (DOY), and the unit of “SOS_merge_r” and “EOS_merge_r” is day.本数据集为北半球植被物候数据集（纬度范围30°N至90°N，经度范围-180°E至180°E），包含季始期（start of season, SOS_merge）、季始期不确定性区间（SOS_merge_r）、季终期（end of season, EOS_merge）以及季终期不确定性区间（EOS_merge_r）。本数据集通过融合四类植被物候数据集生成，这四类数据集分别为MODIS MCD12Q2（https://lpdaac.usgs.gov/products/mcd12q2v061/）、MEaSUREs VIPPHEN（https://lpdaac.usgs.gov/products/vipphen_ndviv004/）、GIMMS NDVI3g（http://data.globalecology.unh.edu/data/GIMMS_NDVI3g_Phenology/）以及GIMMS NDVI4g（https://doi.org/10.5281/zenodo.7649107），融合方法采用可靠性集合平均法（reliability ensemble averaging）。不确定性区间基于各数据集的权重以及可靠性集合平均结果与源数据间的偏差计算得到，不确定性上下限通过可靠性集合平均结果与不确定性区间表征。 该数据集的空间分辨率为0.05°，时间跨度为1982年至2022年。本数据集采用2000年至2018年间280个地面观测站点的PhenoCam数据集进行验证，共获得1410个站点年组合样本。 本数据集以TIFF格式存储，其中季始期（SOS_merge）与季终期（EOS_merge）的单位为日序（day of year, DOY），季始期不确定性区间（SOS_merge_r）与季终期不确定性区间（EOS_merge_r）的单位为天。