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Due to the increasing relevance of analyzing water consumption along product life cycles, the method of Water Footprinting gained rising attention in the last years. In this context the water accounting and vulnerability evaluation model (WAVE+) was developed at the TU Berlin. Based on a consumption-to-availability ratio derived from the hydrological model WaterGap3, WAVE+ currently analyzes the vulnerability of basins to freshwater depletion in more than 8.000 basins. On the accounting level the atmospheric evaporation recycling within drainage basins is considered which can reduce the water consumption volumes within specific basins significantly. However, the model does not consider evaporation recycling patterns across basin boundaries until now.This research focuses on the enhancement of the method by including the latter point. In addition to the consideration of the basin internal evaporation recycling (BIER) the basin external evaporation recycling (BEER) is included for the first time. The main outcome are monthly and basin-specific recycling patterns which are able to show in which drainage basins evaporated water will finally re-precipitate. The results were gained from the atmospheric moisture tracking model WAM-2layers which was fed with climatic input data from the ERA-Interim reanalysis on a 1.5° latitude and 1.5° longitude grid for the period of 2001-2010. With regard to evaporation data, the Era-Interim data were replaced by data of the hydrological model WaterGap3 to ensure consistency with the WAVE+ model. The import and export of water flows were aggregated according to the basin delineation of the WAVE+ method.First results for the region around Berlin show that most of the evaporated water re-precipitates over land, mainly in basins located in Eastern Germany, Poland, Czech Republic, Slovakia and the Ukraine. With regards to the region of Central Borneo most of the re-precipitation takes place on the island itself as well as over the surrounding sea and East Indonesia. In addition to presenting basin-specific recycling patterns, the research discusses methodological aspects on how those results could potentially be used within the scope of Water Footprinting. In order to enable further application purposes, the un-aggregated raw data of the fate analysis of evaporated water will be provided on a 1.5° latitude and 1.5° longitude grid and be made publicly available. [ABSTRACT FROM AUTHOR]

Various studies investigated the fate of evaporation and the origin of precipitation. The more recent studies among them were often carried out with the help of numerical moisture tracking. Many research questions could be answered within this context, such as dependencies of atmospheric moisture transfers between different regions, impacts of land cover changes on the hydrological cycle, sustainability-related questions, and questions regarding the seasonal and interannual variability of precipitation. In order to facilitate future applications, global datasets on the fate of evaporation and the sources of precipitation are needed. Since most studies are on a regional level and focus more on the sources of precipitation, the goal of this study is to provide a readily available global dataset on the fate of evaporation for a fine-meshed grid of source and receptor cells. The dataset was created through a global run of the numerical moisture tracking model Water Accounting Model-2layers (WAM-2layers) and focused on the fate of land evaporation. The tracking was conducted on a 1.5∘×1.5∘ grid and was based on reanalysis data from the ERA-Interim database. Climatic input data were incorporated in 3- to 6-hourly time steps and represent the time period from 2001 to 2018. Atmospheric moisture was tracked forward in time and the geographical borders of the model were located at ±79.5 ∘ latitude. As a result of the model run, the annual, the monthly and the interannual average fate of evaporation were determined for 8684 land grid cells (all land cells except those located within Greenland and Antarctica) and provided via source–receptor matrices. The gained dataset was complemented via an aggregation to country and basin scales in order to highlight possible usages for areas of interest larger than grid cells. This resulted in data for 265 countries and 8223 basins. Finally, five types of source–receptor matrices for average moisture transfers were chosen to build the core of the dataset: land grid cell to grid cell, country to grid cell, basin to grid cell, country to country, basin to basin. The dataset is, to our knowledge, the first ready-to-download dataset providing the overall fate of evaporation for land cells of a global fine-meshed grid in monthly resolution. At the same time, information on the sources of precipitation can be extracted from it. It could be used for investigations into average annual, seasonal, and interannual sink and source regions of atmospheric moisture from land masses for most of the regions in the world and shows various application possibilities for studying interactions between people and water, such as land cover changes or human water consumption patterns. The dataset is accessible under 10.1594/PANGAEA.908705 (Link et al., 2019a) and comes along with example scripts for reading and plotting the data. [ABSTRACT FROM AUTHOR]