本数据集以欧洲中期天气预报中心（ECMWF）ERA5-Land陆面再分析资料为基础数据源（数据访问地址：https://cds.climate.copernicus.eu/datasets/reanalysis-era5-land）。ERA5-Land原生空间分辨率为0.1°×0.1°（约9 km）、时间分辨率为1 h。提取1950–2023年覆盖塔吉克斯坦及周边格网的资料，核心计算窗口为1950年10月1日至2024年9月30日，使用雪水当量、总降水量和降雪量构建雪旱产品。研究区约为36°40′–41°05′N、67°31′–75°14′E；代表性NetCDF文件实际存储格网范围为35.0°–42.0°N、66.0°–76.0°E，采用规则经纬度格网。研究区矢量文件采用WGS 1984地理坐标系。
", "ds_source": "", "ds_process_way": "数据加工包括六个阶段：（1）源数据整理与日尺度聚合：按时间顺序整理ERA5-Land小时资料，完成变量、时间坐标和空间格网的一致化处理，将雪水当量转换为日最大值，将总降水量和降雪量聚合为日累计量。（2）水文年统计：以每年10月1日至次年9月30日为一个水文年，计算水文年最大雪水当量、累计总降水量、累计降雪量及降雪比例。（3）气候参考场构建：采用1950–1979年水文年数据建立各格点最大雪水当量、累计总降水量和降雪比例的气候参考场。（4）总雪旱判识：当某格点某水文年的最大雪水当量低于对应气候参考值时，判定为总雪旱事件。（5）类型化派生：依据累计总降水量和降雪比例相对参考状态的变化，将总雪旱进一步划分为暖雪旱、干雪旱和暖干复合型雪旱。（6）频率计算与产品组织：在塔吉克斯坦研究区1469个有效格点上，生成1950–2023年74个水文年的总雪旱及三类亚型逐年事件格网、逐年区域发生频率和长期格网发生频率，并配套输出气候参考场、水文年最大雪水当量中间产品及研究区边界文件。
", "ds_quality": "数据质量控制覆盖时间完整性、空间维度一致性、变量规范性、复算一致性和水文合理性。逐日源数据按水文年检查均为365或366 d，无缺失日期和重复日期；主要逐年格网产品维度统一为74×101×71，空间分辨率为0.1°，时间轴覆盖1950–2023年。独立复算结果显示，水文年最大雪水当量与发布中间产品的最大绝对差为0，1950–1979年参考场最大差异为0.000488 mm，复算事件格网与发布事件格网在逐年、逐格点尺度上的差异数为0。基于5个GRDC水文站的径流过程对比表明，多个站点在雪旱年份呈现冷季径流增加、暖季径流减少的季节性响应，为数据集的水文一致性提供间接验证。使用时应注意统一雪水当量单位：部分代表性SWEmax文件属性记录为m，而基准场及相关统计采用mm。
", "ds_acq_start_time": "1950-01-01 00:00:00", "ds_acq_end_time": "2024-12-31 00:00:00", "ds_acq_place": "https://cds.climate.copernicus.eu/datasets/reanalysis-era5-land", "ds_acq_lon_east": null, "ds_acq_lat_south": null, "ds_acq_lon_west": null, "ds_acq_lat_north": null, "ds_acq_alt_low": null, "ds_acq_alt_high": null, "ds_share_type": "open-access", "ds_total_size": 1669567208, "ds_files_count": 929, "ds_format": "*.nc, *.tif, *.shp", "ds_space_res": "0.1度", "ds_time_res": "年", "ds_coordinate": "WGS84", "ds_projection": "WGS84", "ds_thumbnail": "8efe98bf-e10a-4eaa-a8b2-a4d6b8d170be.png", "ds_thumb_from": 2, "ds_ref_way": "", "paper_ref_way": "", "ds_ref_instruction": "", "ds_from_station": null, "organization_id": "a5877b42-96ea-4f13-af7e-246f355413d6", "doi_value": "", "subject_codes": [ "170.1535", "170.55" ], "quality_level": 1, "publish_time": "2026-07-21 16:33:29", "first_publish_time": null, "last_updated": "2026-08-21 17:20:00", "protected": false, "protected_to": null, "lang": "zh", "cstr": null, "license": null, "extra": null, "files_shape": [ { "name": "塔吉克斯坦1950–2023年雪旱发生频率及类型化派生格网数据集", "size": null, "is_dir": true } ], "features": null, "data_level": 0, "i18n": { "en": { "title": "", "ds_abstract": "The dataset is based on ERA5-Land land reanalysis data produced by the European Centre for Medium-Range Weather Forecasts (ECMWF) (data access URL: https://cds.climate.copernicus.eu/datasets/reanalysis-era5-land). ERA5-Land has a native spatial resolution of 0.1° × 0.1° (approximately 9 km) and an hourly temporal resolution. Data covering Tajikistan and the surrounding grid were extracted for 1950–2023, with the core calculation window extending from 1 October 1950 to 30 September 2024. Snow water equivalent, total precipitation and snowfall were used to derive the snow-drought products. The approximate study-area extent is 36°40′–41°05′N and 67°31′–75°14′E, whereas representative NetCDF files store a wider regular latitude-longitude grid of 35.0°–42.0°N and 66.0°–76.0°E. The study-area vector files use the WGS 1984 geographic coordinate system.", "ds_source": "", "ds_process_way": "The data processing workflow consists of six stages:\r\n(1) Source-data organization and daily aggregation. Hourly ERA5-Land files were arranged chronologically and harmonized for variables, time coordinates and grids. Snow water equivalent was converted to daily maxima, and total precipitation and snowfall were aggregated to daily totals.\r\n(2) Hydrological-year statistics. Each hydrological year was defined from 1 October to 30 September of the following year. Hydrological-year maximum snow water equivalent, accumulated total precipitation, accumulated snowfall and snowfall fraction were calculated.\r\n(3) Climatological-reference construction. Grid-cell climatological reference fields for maximum snow water equivalent, accumulated total precipitation and snowfall fraction were constructed from hydrological years 1950–1979.\r\n(4) Total snow-drought identification. A grid cell in a given hydrological year was classified as total snow drought when its maximum snow water equivalent was lower than the corresponding climatological reference value.\r\n(5) Type-specific derivation. Total snow-drought events were further divided into warm, dry and warm-dry compound types according to changes in accumulated total precipitation and snowfall fraction relative to their reference states.\r\n(6) Frequency calculation and product organization. For 1,469 valid grid cells in Tajikistan, annual event grids, annual regional occurrence frequencies and long-term gridded occurrence frequencies were generated for total snow drought and its three subtypes across 74 hydrological years from 1950 to 2023. Reference fields, hydrological-year maximum snow water equivalent and study-area boundaries were organized as supporting products.\r\nThe resulting package provides a standardized and reproducible basis for long-term snow-drought analysis in Tajikistan and High Mountain Central Asia.", "ds_quality": "Quality control covers temporal completeness, spatial-dimension consistency, variable standardization, reconstruction consistency and hydrological plausibility. Daily source data contain 365 or 366 days in each hydrological year, with no missing or duplicated dates. The principal annual gridded products share dimensions of 74 × 101 × 71 at 0.1° resolution and cover hydrological years 1950–2023. Independent reconstruction produced a maximum absolute difference of 0 for hydrological-year maximum snow water equivalent, a maximum difference of 0.000488 mm for the 1950–1979 reference field, and zero differing cells between reconstructed and released event grids at both annual and grid-cell scales. Runoff comparisons at five GRDC stations show seasonal responses during snow drought years at several stations, including higher cold-season runoff and lower warm-season runoff, providing indirect evidence of hydrological consistency. Users should normalize snow-water-equivalent units before analysis because the unit attribute in some representative SWEmax files is recorded as m, whereas reference fields and associated statistics use mm.", "ds_acq_place": "https://cds.climate.copernicus.eu/datasets/reanalysis-era5-land", "ds_ref_instruction": "", "ds_ref_way": "", "ds_format": "*.nc, *.tif, *.shp", "ds_projection": "", "ds_space_res": "", "ds_time_res": "" } }, "license_type": null, "doi_reg_from": "reg_local", "cstr_reg_from": "reg_local", "doi_not_reg_reason": null, "cstr_not_reg_reason": null, "is_paper_in_submitting": false, "ds_topic_tags": [ "雪旱发生频率及类型化派生" ], "ds_subject_tags": [ "气候学", "水文学" ], "ds_class_tags": [], "ds_locus_tags": [ "塔吉克斯坦" ], "ds_time_tags": [ 1950, 1951, 1952, 1953, 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023 ], "ds_contributors": [ "王保得", "李玉朋" ], "ds_meta_authors": [ "王保得", "李玉朋" ], "ds_managers": [ "李玉朋" ], "category": "气象" }