DOI: 10.5281/zenodo.13855371
title: Global River BankFull Discharge (GQBF)

description: The GQBF is the estimated bankfull discharge across ~2.87 million km (length) of global river reaches. The bankfull discharge here is defined as the maximum flow rate contained within a river just before inundation occurs in the surrounding floodplain. We based our river bankfull discharge estimation on a newly developed river network, Global RIver Topology (GRIT), using GRIT’s river reaches as the spatial scale to represent the variation in bankfull discharge. We included all GRIT river reaches that coincided with the Global River Width from Landsat (GRWL) river masks (with overlapping ratio >=0.5). This selects river reaches with satellite-derived width measurements >=30 m, resulting in a total length of ~2.87 million km. Here, the GQBF represents the time-averaged bankfull discharge at <1 km (river length) spatial resolution.

We generated this global bankfull discharge dataset using a machine learning model, which was developed based on a newly-compiled, observation-based bankfull discharge dataset and 31 predictors river characteristics and climate. The observation dataset consists of 2,657 sites, sourced and derived from literature values, cross-section measurements, and river gauging transects-based discharge-stage curves. 

We provide the data in both vector and raster format. 

Regions

Vector files are provided in 7 regions with the following codes:



AF - Africa

AS - Asia (excl. Siberia)

EU - Europe

NA - North America

SA - South America

SI - Siberia

SP - South Pacific/Australia


The subcontinental catchment groups (vector, polygons) can be found at GRIT domain polygon (GRITv06_domain_GLOBAL.gpkg.zip). They allow for more fine-grained subsetting of data .

Vector files are provided in geographic WGS84 coordinates (EPSG:4326).

Vector

GRIT reaches

GRIT reaches with a list of attributes, including the estimated QBF. These river reaches represent rivers overlapping with the Global River Width from Landsat river mask, selected by grwl_overlap>=0.5. Other attributes inherit from the GRIT reaches dataset (available at https://zenodo.org/records/112193130 )

Attribute description




Name
Data type
Description


domain
text
catchment group, see domain index file


segment_id
integer
global segment ID of reach


cat
integer
domain internal feature ID


reach_id
integer
global river reach ID, same as FID


catchment_id
integer
global catchment ID


upstream_node_id
integer
global reach node ID at upstream end of line


downstream_node_id
integer
global reach node ID at downstream end of line


upstream_line_ids
text
comma-separated list of global river reach IDs connecting at upstream end of line


downstream_line_ids
text
comma-separated list of global river reach IDs connecting at downstream end of line


grwl_overlap
float
the overlapping ratio between the river network and the GRWL river mask


grwl_width_median
float
the median value of river width along each reach, calculated from the GRWL river mask in m


grwl_width_std
float
the standard deviation of river width along each reach, calculated from the GRWL river mask in m


grwl_value
integer
dominant GRWL value of reach


length
float
length of reach in m


sinuousity
float
ratio of line length and Euclidian distance between upstream-downstream nodes, i.e. 1 meaning a perfectly straight line


azimuth
float
direction of line connecting upstream-downstream nodes in degrees from North


qbf
float
the estimated bankfull discharge for each reach (m3/s)


drainage_area
float
the upstream accumulated drainage area (km2)


is_mainstem
integer
1: the GRIT reach belongs to a mainstem river segment; 0:  the GRIT reach belongs to a non-mainstem river segment




Raster

The raster version of the GRIT reaches (spatial resolution is 100 m). It includes 5 bands listed in order below.

The raster files are chunked into 10 by 10 latitude, longitude degrees. In total, there are xx files, tiles without rivers are not included. A vector file of the tiles boundary is provided. Null value is indicated as -1.




qbf
integer
the estimated bankfull discharge for each reach (m3/s)


drainage_area
integer
the upstream accumulated drainage area (km2)


river width
integer
the median value of river width along each reach, calculated from GRWL river mask in m, i.e., grwl_width_median above


grwl_value
integer
dominant GRWL value of reach


is_mainstem
integer
1: the GRIT reach belongs to a mainstem river segment; 0:  the GRIT reach belongs to a non-mainstem river segment




Additional

A vector file of the tiles boundary is provided as Global_tiles_10by10.GPKG.

Change log



v0.1 - 2024-09-29



First globally complete dataset published