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and Hydrology Data Access","monthly_downloads":0,"total_dependent_repos":0,"total_dependent_packages":0,"readme":"**************\nGlobalDeltaChange\n**************\n\n.. image:: https://zenodo.org/badge/191585237.svg\n   :target: https://zenodo.org/badge/latestdoi/191585237\n    \n.. image:: https://app.codacy.com/project/badge/Grade/0ae4939efdcd43b9b70e3ac605619f50\n    :target: https://www.codacy.com/gh/jhnienhuis/GlobalDeltaChange/dashboard?utm_source=github.com\u0026amp;utm_medium=referral\u0026amp;utm_content=jhnienhuis/GlobalDeltaChange\u0026amp;utm_campaign=Badge_Grade\n    \n\n    \n*GlobalDeltaChange* is a (1) theoretical framework to predict delta morphology and delta change, and (2) a set of codes to make this predictions on a global scale for ~11,000 deltas. Results and methods are described in `Nienhuis et al., 2020 \u003chttps://www.nature.com/articles/s41586-019-1905-9\u003e`_\n\n.. figure:: https://media.springernature.com/full/springer-static/image/art%3A10.1038%2Fs41586-019-1905-9/MediaObjects/41586_2019_1905_Fig1_HTML.png?as=webp\n    \n    Global delta morphology, as predicted by three sediment fluxes (Qwave, Qtide, and Qriver), within a ternary space and along Earths' coast.\n\nDocumentation\n#############\n\nVersioning\n**********\n\nby Jaap Nienhuis, Utrecht University, 2019, version 1.0\nby Jaap Nienhuis, Utrecht University, 2021, version 2.0\n(Version 2.0 includes the newest land/water change data from GSW, local wave estimates from local wind fetch, submarine and subaerial elevation, river names, and more.)\n\nUse the data\n#############\n\nThe data can be viewed interactively in `a GEE App \u003chttps://jhnienhuis.users.earthengine.app/view/globaldelta\u003e`_.\nRaw data is available here on github, formatted as `MATLAB .mat \u003chttps://github.com/jhnienhuis/GlobalDeltaChange/blob/master/GlobalDeltaData.mat\u003e`_, `Shapefiles \u003chttps://github.com/jhnienhuis/GlobalDeltaChange/blob/master/export_data/GlobalDeltaMouth_shp.zip\u003e`_, `NetCDF .nc \u003chttps://github.com/jhnienhuis/GlobalDeltaChange/blob/master/export_data/GlobalDeltaData.nc\u003e`_, and `.kml \u003chttps://github.com/jhnienhuis/GlobalDeltaChange/blob/master/export_data/GlobalDeltaData.kml\u003e`_ files. \n\nReproduce the data\n#############\n\nTo reproduce the GlobalDeltaData.mat file, run the following functions in this order: \n\nMain functions\n**********\n(1) find_river_mouth.m\n    uses hydrosheds, DIVA, Durr, and SRTM to find all alluvial river mouths globally, furtheron referred to as deltas. Initiates the GlobalDeltaData.mat file\n\n(2) get_QRiver.m\n    uses WBMSED to get a pristine and disturbed sediment and water flux to each delta. Optionally you can use get_QRiver_timeseries to get daily QRiver and Discharge output\n\n(3) get_channel_slope.m\n    uses SRTM and hydrosheds to extract river elevation profiles for all deltas up to 30 meters elevation\n    \n(4) get_bathy_profile.m\n    uses etopo data to get steepest descent profiles of the underwater basin depths, from the river mouth to -100m\n    \n(5) get_Qwave.m\n    adds wave data to each delta from WaveWatch. For deltas that are (partially) sheltered from wave approach angles, it estimates a fetch based on shoreline orientation.\n    It uses the bretschneider fetch formula and WaveWatch wind data to estimate wave heights in sheltered locations. Uses get_global_fetch.m. \n    Optionally you can use get_QWave_timeseries to get daily wave statistics, or get_QWave_future to get estimates of future wave heights (up to 2100).\n\n(6) get_Qtide.m\n    adds tide data to each delta, based on TOPEX data\n    \n(7) get_hydrobasins_id.m\n    adds identifiers from the new WWF HydroATLAS, HydroBasins, and HydroRIVERS datasets\n\n(8) add_names_to_deltas.m\n    Uses FAO data to find river names for deltas, where available. Needs updating.\n\nSupplemental functions\n**********\n\nland_area_change/get_aquamonitor_data\n    defines polygons for each river delta, and retrieves aquamonitor and earthsurfacewater explorer data to get delta coastal area land gain and loss within those regions. \n    These data are noisy, so use with caution and with appropriate estimates of data uncertainty. The GEE code can be found at:\n    https://code.earthengine.google.com/21dd5f216c625b8696b4d9af6ee55215\n    We manually define polygons for the 100 largest deltas (see GlobalDeltaMax100.kml), and use proxies for delta area size for the remaining deltas.\n    \nexport_data/create_kml, create_netcdf, create_shapefile, create_shapefile_deltaland\n    various functions to export relevant data to kml, netcdf, xlsx, and shapefile formats\n    \nmisc/galloway_predictor\n    function to plot output in the galloway triangle.\n\nvalidation/global_delta_validation\n    function to compare predictions against observations and put the resulting accuracy in the readme.rst file on github\n    \nInput datasets\n#############\n\nReproducing the data can be done with the following input datasets:\n\n- HydroSheds 15 arcsec drainage direction (DIR), flow accumulation (ACC), and basin outline (BAS) files\nsource: https://www.hydrosheds.org/\n\n- DIVA typology_coastline\nsource: AT Vafeidis, G Boot, J Cox, R Maatens, L McFadden, RJ Nicholls, T Spencer, RSJ Tol, (2006) The DIVA database documentation, DINAS-COAST Consortium\n\n- DURR dataset\nsource: Dürr, H.H., Laruelle, G.G., van Kempen, C.M. et al. Estuaries and Coasts (2011) 34: 441. https://doi.org/10.1007/s12237-011-9381-y\n\n- NOAA vectorized shoreline\nsource: https://www.ngdc.noaa.gov/mgg/shorelines/\n\n- WBMSed global discharge, pristine, and disturbed sediment fluxes\nsource: https://sdml.ua.edu/datasets-2/\n\n- Global directional wave statistics (WaveWatch), and global tides (TOPEX)\nsource: https://jhnienhuis.users.earthengine.app/view/changing-shores\n\n- SRTM, 1 arcsec (30 meter) resolution global topography\nsource: https://lpdaac.usgs.gov/products/srtmgl1v003/\n\n- River Names, from FAO Aquamaps\nsource: http://www.fao.org/nr/water/aquamaps/\n\n(note, I don't store these here because of versioning and file size limitations. Please get in touch if you can't find them, I will send them to you)\n\nGlobal Delta Accuracy\n#############\n\nThe accuracy of the global delta dataset is assessed through comparison against field measurements and other datasets, scipts are validation data are in the subfolder \"validation\".\n\nWe compare the total number of predicted deltas (~11,000) against field observations of deltas that meet our definition (see the publication). We also compare the predicted morphology and give accuracy for individual predictions and for the global total. Lastly, we compare the delta land area change against a set of other datasets and observations.\n\nFor deltas on Madagascar, and additional deltas drawn at random from the dataset, we obtain the following confusion matrix:\n\n+-----------+------------+------------+-----------+---------+\n|           |              Observed                         |\n+===========+============+============+===========+=========+\n|           |            | Wave       | River     | Tide    |\n+-----------+------------+------------+-----------+---------+\n|           | Wave       | 244        |  011      | 033     |\n+-----------+------------+------------+-----------+---------+\n| Predicted | River      | 020        |  025      | 018     |\n+-----------+------------+------------+-----------+---------+\n|           | Tide       | 003        |  001      | 017     |\n+-----------+------------+------------+-----------+---------+\n\nFor individual predictions, we retrieve the following accuracies\n\n================    =======================\nMorphology          Prediction accuracy (%)\n----------------    -----------------------\nWave dominated               89%\nRiver dominated              65%\nTide dominated               23%\n================    =======================\n\nScaling up to the globe, we retrieve the following estimates for the global number of deltas and their morphologies\n\n================    ==============  =======================\nMorphology          Global number   Uncertainty (+/- 1std)\n----------------    --------------  -----------------------\nAll deltas            10848             0371\nWave dominated        08245             0894 \nRiver dominated       01825             0633\nTide dominated        00778             0601\n================    ==============  =======================\n\nThe accuracy of our Aquamonitor-derived land area change estimats for global deltas is assessed by comparison against other models, and individual delta assessments.\n\n================    ==============  =======================\nSelection            Percentage of      Expressed in \n                     delta change       Area (km2/yr)  \n----------------    --------------  -----------------------\nDetection error         001%                001.00\nMapping error           153%                152.64\nIntermodel error        092%                092.16\n----------------    --------------  -----------------------\nOne delta (mean)        246%                245.80\nAll deltas (SE)         103%                103.16 \n================    ==============  =======================\n\n\n\n\n\n\n\n\n","funding_links":[],"readme_doi_urls":["https://doi.org/10.1007/s12237-011-9381-y"],"works":{},"citation_counts":{},"total_citations":0,"keywords_from_contributors":[],"project_url":"https://ost.ecosyste.ms/api/v1/projects/173395","html_url":"https://ost.ecosyste.ms/projects/173395"}