Lake-TopoCat: A global Lake drainage Topology and Catchment database

Contact: Md Safat Sikder ([e-mail]), Jida Wang ([e-mail]; [e-mail]) Citation If you use Lake-TopoCat, please cite the following ESSD preprint for now: Sikder, M. S., Wang, J., Allen, G. H., Sheng, Y., Yamazaki, D., Song, C., Ding, M., Crétaux, J.-F., and Pavelsky, T. M., 2023. Lake-TopoCat: A global lake drainage topology and catchment dataset. Earth System Science Data Discussion, in review, https://doi.org/10.5194/essd-2022-433. Data description and componentsThis version of Lake-TopoCat was constructed using the HydroLAKES v1.0 (Messager et al., 2016) lake mask and the 3-arc-second-resolution hydrography dataset MERIT Hydro v1.0.1 (Yamazaki et al., 2019). The drainage type of each HydroLAKES lake, such as isolated, inflow-headwater, headwater, flow-through, terminal, and coastal, was determined with assistance of MERIT Hydro-Vector (Lin et al., 2021), a high-resolution river network dataset with spatially-variable drainage densities. For convenience, the global landmass (excluding Antarctica) was partitioned to 68 Pfafstetter Level-2 basins or regions, and the Lake-TopoCat data products were also organized based on these 68 regions, with their region or basin IDs shown in the Fig. 'Pfaf2_basins.jpg', attached to this database. Lake-TopoCat consists of five feature components, each with multiple attributes depicting lake drainage relationships. The five features are: 1. Lake boundaries: polygons of 1,426,967 HydroLAKES lakes, larger than 10 ha. File name: Lakes_pfaf_xx where, 'pfaf_xx' indicates the Pfafstetter Level-2 basin ID (shown in Fig. 'Pfaf2_basins.jpg') 2. Lake outlets: points representing outlet or pour points of each individual lake. There are multiple outlets from a multifurcation lake. We identified 1,459,201 outlets for 1,426,967 lakes, where 29,190 lakes (~2% of the global lakes) show bi/multifurcation. File name: Outlets_pfaf_xx 3. Unit catchment: boundary polygons of catchment defining the drainage areas between cascading (i.e., immediately upstream and downstream) lake outlets. The count of unit catchments equal to the count of lake outlets, and bifurcation or multifurcation lakes have multiple local catchments. In total, the delineated catchments in Lake-TopoCat cover about 77.5 million km2, which is about 57% of the Earth’s land mass excluding the Antarctic. File name: Catchments_pfaf_xx 4. Inter-lake reaches: line features defining the drainage networks that connect the lake outlets to the inland sinks or the ocean. About 3 million connecting reaches were generated among ~1.4 million outlets. The total length of these inter-lake connecting reaches is ~10 million km. File name: Reaches_pfaf_xx 5. Lake-network basins: boundary polygons of the entire drainage area containing each inter-lake network (i.e., a complete basin from the headwater to an inland sink or the ocean for all basins containing lakes). A total of 47,340 lake-network basins were identified. Among them, endorheic basins account for 5.1% by count and 18% by area of all lake-network basins. These endorheic basins cover ~15.4% of global surface excluding Antarctica. File name: Basins_pfaf_xx The attribute tables for each of the feature components are explained in Section 4 of the product description document. For user convenience, we release the preliminary Lake-TopoCat lake outlets, unit catchments, and inter-lake reaches, with the affix '_prelim' in the file names (explained in the attached product description document). We also provide the polygon boundaries of the 68 Pfafstetter basins or regions in the file named 'Pfaf2_regions'. All files of Lake-TopoCat are available in both shapefile and geodatabase formats. DisclaimerAuthors of this dataset claim no responsibility or liability for any consequences related to the use, citation, or dissemination of Lake-TopoCat.联系方式：Md Safat Sikder（邮箱：[e-mail]）、Jida Wang（邮箱：[e-mail]; [e-mail]） 引用说明 若使用Lake-TopoCat数据集，请暂时引用以下《地球系统科学数据讨论》（Earth System Science Data Discussion）预印本： Sikder, M. S., Wang, J., Allen, G. H., Sheng, Y., Yamazaki, D., Song, C., Ding, M., Crétaux, J.-F. 及 Pavelsky, T. M., 2023. Lake-TopoCat: 全球湖泊排水拓扑与集水区数据集。《地球系统科学数据讨论》（Earth System Science Data Discussion），已投稿待刊，https://doi.org/10.5194/essd-2022-433. 数据说明与组成 本版本Lake-TopoCat数据集基于HydroLAKES v1.0（Messager等，2016）湖泊掩膜产品，以及3弧秒分辨率的水文数据集MERIT Hydro v1.0.1（Yamazaki等，2019）构建。每个HydroLAKES湖泊的排水类型（如孤立型、入流源头型、源头型、贯通型、终端型及沿海型），借助高分辨率河网数据集MERIT Hydro-Vector（Lin等，2021）确定，该数据集具备空间可变的排水密度。 为便于使用，全球陆域（不含南极洲）被划分为68个Pfafstetter二级流域（Pfafstetter Level-2 basins），Lake-TopoCat数据产品也基于这68个区域进行组织，各区域或流域的ID详见本数据库附带的「Pfaf2_basins.jpg」图件。 Lake-TopoCat包含5类要素组件，每类均包含多个刻画湖泊排水关系的属性字段。5类要素分别为： 1. 湖泊边界：涵盖1,426,967个面积大于10公顷的HydroLAKES湖泊的多边形矢量数据。 文件命名格式：Lakes_pfaf_xx，其中「pfaf_xx」代表Pfafstetter二级流域（Pfafstetter Level-2 basins）ID（详见「Pfaf2_basins.jpg」图件） 2. 湖泊出口：代表单个湖泊出口或汇流点的点要素。多分叉湖泊存在多个出口。本次研究为1,426,967个湖泊共识别出1,459,201个出口，其中29,190个湖泊（约占全球湖泊总数的2%）存在双向/多分叉排水结构。 文件命名格式：Outlets_pfaf_xx 3. 单位集水区：刻画级联（即紧邻上下游）湖泊出口间汇水范围的边界多边形。单位集水区的数量与湖泊出口总数一致，分叉或多分叉湖泊对应多个局部集水区。Lake-TopoCat中绘制的集水区总面积约为7750万平方千米，约占除南极洲外全球陆域面积的57%。 文件命名格式：Catchments_pfaf_xx 4. 湖间河道：连接湖泊出口与内陆汇水区或海洋的河网线要素。本次研究为约140万个出口间生成了约300万条连接河道，总长度约为1000万千米。 文件命名格式：Reaches_pfaf_xx 5. 湖网流域：包含每条湖间河网的完整汇水区域边界多边形（即所有含湖流域从源头到内陆汇水区或海洋的完整流域范围）。本次研究共识别出47,340个湖网流域，其中内流盆地（endorheic basins）占总数的5.1%，总面积占所有湖网流域总面积的18%。这类内流盆地覆盖了除南极洲外全球陆地表面积的约15.4%。 文件命名格式：Basins_pfaf_xx 各要素组件的属性表详见产品说明文档第4节。为方便用户使用，我们同步发布了带「_prelim」后缀的初步版Lake-TopoCat湖泊出口、单位集水区及湖间河道数据（详细说明见附带的产品说明文档）。此外，我们还提供了68个Pfafstetter流域或区域的多边形边界文件，文件名为「Pfaf2_regions」。Lake-TopoCat所有数据均提供shapefile与地理数据库（geodatabase）两种格式。 免责声明 本数据集作者不对因使用、引用或传播Lake-TopoCat所引发的任何后果承担责任或义务。