ERA5-Land weekly: Air temperature at 2 meter above surface, weekly time series for Europe at 1 km resolution (2016 - 2020)

Overview: ERA5-Land is a reanalysis dataset providing a consistent view of the evolution of land variables over several decades at an enhanced resolution compared to ERA5. ERA5-Land has been produced by replaying the land component of the ECMWF ERA5 climate reanalysis. Reanalysis combines model data with observations from across the world into a globally complete and consistent dataset using the laws of physics. Reanalysis produces data that goes several decades back in time, providing an accurate description of the climate of the past. Air temperature (2 m): Temperature of air at 2m above the surface of land, sea or in-land waters. 2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. Processing steps: The original hourly ERA5-Land data has been spatially enhanced from 0.1 degree to 30 arc seconds (approx. 1000 m) spatial resolution by image fusion with CHELSA data (V1.2) (https://chelsa-climate.org/). For each day we used the corresponding monthly long-term average of CHELSA. The aim was to use the fine spatial detail of CHELSA and at the same time preserve the general regional pattern and fine temporal detail of ERA5-Land. The steps included aggregation and enhancement, specifically: 1. spatially aggregate CHELSA to the resolution of ERA5-Land 2. calculate difference of ERA5-Land - aggregated CHELSA 3. interpolate differences with a Gaussian filter to 30 arc seconds 4. add the interpolated differences to CHELSA The spatially enhanced daily ERA5-Land data has been aggregated on a weekly basis starting from Saturday for the time period 2016 - 2020. Data available is the weekly average of daily averages, the weekly minimum of daily minima and the weekly maximum of daily maxima of air temperature (2 m). File naming: Average of daily average: era5_land_t2m_avg_weekly_YYYY_MM_DD.tif Max of daily max: era5_land_t2m_max_weekly_YYYY_MM_DD.tif Min of daily min: era5_land_t2m_min_weekly_YYYY_MM_DD.tif The date in the file name determines the start day of the week (Saturday). Pixel value: °C * 10 Example: Value 44 = 4.4 °C The QML or SLD style files can be used for visualization of the temperature layers. Coordinate reference system: ETRS89 / LAEA Europe (EPSG:3035) (EPSG:3035) Spatial extent: north: 82:00:30N south: 18N west: 32:00:30W east: 70E Spatial resolution: 1km Temporal resolution: weekly Time period: 01/01/2016 - 12/31/2020 Format: GeoTIFF Representation type: Grid Software used: GDAL 3.2.2 and GRASS GIS 8.0.0 (r.resamp.stats -w; r.relief) Lineage: Dataset has been processed from original Copernicus Climate Data Store (ERA5-Land) data sources. As auxiliary data CHELSA climate data has been used. Original ERA5-Land dataset license: https://cds.climate.copernicus.eu/api/v2/terms/static/licence-to-use-copernicus-products.pdf CHELSA climatologies (V1.2): Data used: Karger D.N., Conrad, O., Böhner, J., Kawohl, T., Kreft, H., Soria-Auza, R.W., Zimmermann, N.E, Linder, H.P., Kessler, M. (2018): Data from: Climatologies at high resolution for the earth's land surface areas. Dryad digital repository. http://dx.doi.org/doi:10.5061/dryad.kd1d4 Original peer-reviewed publication: Karger, D.N., Conrad, O., Böhner, J., Kawohl, T., Kreft, H., Soria-Auza, R.W., Zimmermann, N.E., Linder, P., Kessler, M. (2017): Climatologies at high resolution for the Earth land surface areas. Scientific Data. 4 170122. https://doi.org/10.1038/sdata.2017.122 Other resources: https://data.mundialis.de/geonetwork/srv/eng/catalog.search#/metadata/601ea08c-0768-4af3-a8fa-7da25fb9125b Processed by: mundialis GmbH & Co. KG, Germany (https://www.mundialis.de/) Contact: mundialis GmbH & Co. KG, [e-mail] Acknowledgements: This study was partially funded by EU grant 874850 MOOD. The contents of this publication are the sole responsibility of the authors and don't necessarily reflect the views of the European Commission.概述： ERA5-Land 是一套再分析数据集，相较于 ERA5，其空间分辨率得到提升，可在数十年尺度上一致呈现陆面变量的演化过程。该数据集通过再演 ECMWF 欧洲中期天气预报中心（European Centre for Medium-Range Weather Forecasts）ERA5 气候再分析的陆面分量生成。再分析将模式数据与全球观测数据相结合，依据物理定律构建出一套全球完整且一致的数据集。再分析可回溯数十年的历史数据，精准刻画过去的气候状况。 2米气温： 指陆地、海洋或内陆水域地表以上2米处的空气温度。2米气温通过在最低模式层与地球表面之间插值计算得到，同时考虑了大气状况。 处理流程： 原始 ERA5-Land 逐小时数据通过与 CHELSA（V1.2）数据（https://chelsa-climate.org/）进行图像融合，将空间分辨率从0.1度提升至30角秒（约1000米）。每日计算中，我们使用对应月份的CHELSA长期平均数据。本次处理旨在保留CHELSA的精细空间细节，同时兼顾ERA5-Land的区域整体格局与精细时间分辨率。具体处理步骤包括聚合与增强，详情如下： 1. 将CHELSA数据空间聚合至ERA5-Land的分辨率 2. 计算ERA5-Land与聚合后CHELSA数据的差值 3. 使用高斯滤波器将差值插值至30角秒分辨率 4. 将插值后的差值添加至CHELSA数据 经过空间增强的逐日ERA5-Land数据已按周为单位进行聚合，周起始日为周六，时间覆盖2016年至2020年。可用数据包含2米气温的逐日平均气温周均值、逐日最低气温周最小值以及逐日最高气温周最大值。 文件命名规则： 逐日平均气温的周平均值：era5_land_t2m_avg_weekly_YYYY_MM_DD.tif 逐日最高气温的周最大值：era5_land_t2m_max_weekly_YYYY_MM_DD.tif 逐日最低气温的周最小值：era5_land_t2m_min_weekly_YYYY_MM_DD.tif 文件名中的日期代表当周的起始日（周六）。 像素值： 单位为°C × 10，示例：像素值44对应4.4°C。 可使用QML或SLD样式文件实现气温图层的可视化。 坐标参考系统： ETRS89 / LAEA Europe（EPSG:3035）（EPSG:3035） 空间范围： 北：82°00′30″N 南：18°N 西：32°00′30″W 东：70°E 空间分辨率：1km 时间分辨率：周 时间范围：2016/01/01 - 2020/12/31 数据格式：GeoTIFF 表现类型：网格（Grid） 使用软件：GDAL 3.2.2 与 GRASS GIS 8.0.0 (r.resamp.stats -w; r.relief) 数据谱系： 本数据集源自原始的哥白尼气候数据服务中心（Copernicus Climate Data Store）ERA5-Land数据源，辅助数据采用了CHELSA气候数据。 原始ERA5-Land数据集许可协议：https://cds.climate.copernicus.eu/api/v2/terms/static/licence-to-use-copernicus-products.pdf CHELSA气候态数据（V1.2）： 所用数据：Karger D.N., Conrad, O., Böhner, J., Kawohl, T., Kreft, H., Soria-Auza, R.W., Zimmermann, N.E, Linder, H.P., Kessler, M. (2018)：地球陆表区域高分辨率气候态数据。Dryad数字仓储。http://dx.doi.org/doi:10.5061/dryad.kd1d4 原始同行评议论文：Karger, D.N., Conrad, O., Böhner, J., Kawohl, T., Kreft, H., Soria-Auza, R.W., Zimmermann, N.E., Linder, P., Kessler, M. (2017)：地球陆表区域高分辨率气候态数据。《科学数据》（Scientific Data），4卷，170122。https://doi.org/10.1038/sdata.2017.122 其他资源：https://data.mundialis.de/geonetwork/srv/eng/catalog.search#/metadata/601ea08c-0768-4af3-a8fa-7da25fb9125b 处理方：德国mundialis GmbH & Co. KG（https://www.mundialis.de/） 联系方式：mundialis GmbH & Co. KG，[e-mail] 致谢： 本研究部分由欧盟资助项目MOOD（项目编号874850）支持。本文内容仅代表作者观点，不必然反映欧盟委员会的立场。