Data: Cutting the costs of coastal protection by integrating vegetation in flood defences.

Added in Version 5:

File: transectdata_December2025.nc
Fields:
(1) fid                        = id of transects
(2) x                          = distance across transect in meters
(3) elev_foreshore    = elevation of the foreshore in meters above approximately MSL
(4) vegetation          = Boolean indicating marsh or mangrove presence
(5) veg_type             = vegetation type, marsh == 1, mangroves == 2
(6) veg_z0                = elevation at the start of the vegetated zone (m+MSL)
(7) lon                      = longitude EPSG4326 of centroids of the transects
(8) lat                       = latitude EPSG4326 of the centroids of the transects

Description: 
This dataset includes transect data derived from global data layers following the methodology of Van Zelst et al. (2021), with several updates implemented in support of the study by Willemsen et al. (2026):
1) updated the elevation dataset with DeltaDTM,,
2) updated the marsh dataset using data by Worthington et al. (2024)
3) filtered sheltered vegetation areas that are not preceded by at least 1km water body or are located behind higher landscape features, 
4) corrected for false positives in areas with steep terrain transitions.

Version 4:

GlobalIntertidalElevation_res1arcsec.zip
Zip file containing Global Intertidal Elevation raster tiles plus *.vrt file. Additional information can be found in the metadata file that is part of the *.zip-file.

File: levee_crest_height_reduction_per_country_version_July2021.nc
Fields:     (1) Crest height reduction m per km along the populated coastline susceptible to flooding (return period = 100 years)
                (2) Crest height reduction cost saving per country in million USD₂₀₀₅ PPP along the populated coastline susceptible to flooding (return period = 100 years)
           (3) Cost savings as percentage of GDP₂₀₀₅ along the urban populated coastline susceptible to flooding (return period = 100 years)

File: transectdata_version_July2021.nc
 Transectdata of vegetated transects within the study area.
Fields: 
(1) rps             = return period            
(2) fid             = id of the transects
(3) centroids       = coordinates of the transects
(4) inun            = (1) in area susceptible to flooding
(5) urban           = (1) in urban area, (0) not in urban area
(6) veg_width       = derived coastal vegetation belt width along the foreshore
(7) veg_type        = derived coastal vegetation type along the foreshore (1: salt marshes, 2: mangroves)
(8) hsig            = Offshore significant wave heights (multiple return periods) corresponding to the transects
(9) wave period     = Offshore peak wave period (multiple return periods) corresponding to the transects
(10) surge          = Extreme water level combination of surge and tide (m +MSL) (multiple return periods)
(11) veg_z0         = elevation at the start of the vegetated zone (m +MSL)
(12) hrms_end_noveg = root mean square wave height at the end of the foreshore (without vegetation) (multiple return periods)
(13) hrms_endveg       = root mean square wave height at the end of the foreshore (with vegetation) (multiple return periods) 
(14) pdens_15km        = population density derived using buffer of 15 kilometre radius