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Plastic waste increasingly accumulates in the marine environment, but data on the distribution and quantification of riverine sources required for development of effective mitigation are limited. Our model approach includes geographically distributed data on plastic waste, land use, wind, precipitation, and rivers and calculates the probability for plastic waste to reach a river and subsequently the ocean. This probabilistic approach highlights regions that are likely to emit plastic into the ocean. We calibrated our model using recent field observations and show that emissions are distributed over more rivers than previously thought by up to two orders of magnitude. We estimate that more than 1000 rivers account for 80% of global annual emissions, which range between 0.8 million and 2.7 million metric tons per year, with small urban rivers among the most polluting. These high-resolution data allow for the focused development of mitigation strategies and technologies to reduce riverine plastic emissions.

Population growth, increasing energy demand and depleting fossil fuel resei-ves put a pressure on conventional methods of electricity generation. Hydropower is an alternative energy source that is known to have a large capacity potential. However, previous estimations of the potential capacity have been inconsistent and incomplete. In this study we identified all locations on East Asian islands (from Japan, Taiwan Phillipines to Indonesia) which are suitable for hydropower. For this we combined USGS's HydroSHEDS elevation data with Global Runoff data from the Global Runoff Data Centre. Such large spatially data gives especially unique information which was not available before. We computed that the total gross hydropower capacity potential is about 2885 TWh per year. Large hydropower accounts for over 27% of this potential, around 39% by small plants, 28% by mini hydropower plants, while micro hydropower only accounts for 6 % of the total potential capacity. Overall this study provides spatially detailed global data that allows both a quick comparison of hydropower potential between regions as well as detailed information on specific hydropower locations, which is especially unique new information for micro hydropower., Water Management, Civil Engineering and Geosciences

A continuous population growth and increasing energy demand combined with depleting traditional energy reserves puts a pressure on conventional methods of electricity generation. The desire and ambition to create a more sustainable society paves the way for the ‘renewables’. Hydropower or Hydroelectricity already plays a significant role in global energy production, especially the large hydropower plants with giant reservoir lakes. The contribution of small and micro hydropower however is not really clear. Smaller hydropower plants have some advantages compared to larger plants in terms of sustainability, local benefits and electricity supply in remote areas. The exact location of potential hydropower plants is mostly unknown and the total potential of all combined hydropower capacities for a certain region has not been evaluated as well. This research aims to give insight in the potential of hydropower for a specific region and distinguishes micro, small and large hydropower. In order to evaluate the global hydropower potential a systematical method has been developed to simulate input data and check whether there is hydropower at a specific location. The approach is based on a distributed model and raster data. The world is divided into cells with a 3” (three seconds or 92m near the equator) resolution. For each and every cell the hydropower capacity is systematically determined. In order to do this the two basic components for hydropower, head and discharge need to be evaluated for each cell. The discharge is calculated with help of the HydroSHEDS’ DEM and DIR datasets combined with the GRDC Runoff fields’ dataset. Based on the Flow Direction, derived by HydroSHEDS a ‘runoff weighted’ flow accumulation was executed to obtain the accumulated runoff for each cell which is converted into discharge. The head is calculated with the cell size and slope within each cell. The slope was derived from a global 3” DEM which has been modified with the discharge map to obtain, Water Resources, Water Management, Civil Engineering and Geosciences