Abstract
Study region
Nile basin.
Study focus
Several studies have shown a relationship between climate change and changes in sediment yield. However, there are limited modeling applications that study this relationship at regional scales mainly due to data availability and computational cost. This study proposes a methodological framework using the SWAT+ model to predict and project sediment yield at a regional scale in data-scarce regions using global datasets. We implement a framework that (a) incorporates topographic factors from high/medium resolution DEMs (b) incorporates crop phenology data (c) introduces an areal threshold to linearize sediment yield in large model units and (d) apply a hydrological mass balance calibration. We test this methodology in the Nile Basin using a model application with (revised) and without (default) the framework under historical and future climate projections.
New hydrological insights for the region
Results show improved sediment yield estimates in the revised model, both in absolute values and spatial distribution when compared to measured and reported estimates. The contemporary long term (1989 – 2019) annual mean sediment yield in the revised model was 1.79 t ha−1 yr−1 and projected to increase by 61 % (44 % more than the default estimates) in the future period (2071 – 2100), with the greatest sediment yield increase in the eastern part of the basin. Thus, the proposed framework improves and influences modeled and predicted sediment yield respectively.
Nile basin.
Study focus
Several studies have shown a relationship between climate change and changes in sediment yield. However, there are limited modeling applications that study this relationship at regional scales mainly due to data availability and computational cost. This study proposes a methodological framework using the SWAT+ model to predict and project sediment yield at a regional scale in data-scarce regions using global datasets. We implement a framework that (a) incorporates topographic factors from high/medium resolution DEMs (b) incorporates crop phenology data (c) introduces an areal threshold to linearize sediment yield in large model units and (d) apply a hydrological mass balance calibration. We test this methodology in the Nile Basin using a model application with (revised) and without (default) the framework under historical and future climate projections.
New hydrological insights for the region
Results show improved sediment yield estimates in the revised model, both in absolute values and spatial distribution when compared to measured and reported estimates. The contemporary long term (1989 – 2019) annual mean sediment yield in the revised model was 1.79 t ha−1 yr−1 and projected to increase by 61 % (44 % more than the default estimates) in the future period (2071 – 2100), with the greatest sediment yield increase in the eastern part of the basin. Thus, the proposed framework improves and influences modeled and predicted sediment yield respectively.
| Original language | English |
|---|---|
| Article number | 101152 |
| Journal | Journal of Hydrology: Regional Studies |
| Volume | 42 |
| DOIs | |
| Publication status | Published - Aug 2022 |
Bibliographical note
Funding Information:The authors thank the Research Foundation – Flanders ( FWO ) for funding the International Coordination Action (ICA) “Open Water Network: Open Data and Software tools for water resources management” (project code G0E2621N ), the Flemish Research Council ( VLIR ) for funding the JOINT project “Global Open Water Academic Network: Joint Research and Education on Open Source Software for Integrated Water Resources Management” (project code TZ2019JOI022A105 ) and the European Union H2020 programme for funding “Water-ForCE – Water scenarios For Copernicus Exploitation” (grant agreement No. 101004186 ).
Publisher Copyright:
© 2022 The Authors