Submitted to Earth Interactions.
As a first step toward designing a comprehensive model for validating land-surface hydrology and river flow in Earth system models, a global river channel network on a 1 degree lat. x 1 degree lon. resolution has been prepared. The final product contains Total Runoff Integrating Pathways (TRIP).
The aim of TRIP is to provide information of lateral water movement on the global scale in river channels over the continents. Flow directions were determined from vector data of river channels and river pathways in atlases; however, the results of an automatic procedure using a digital elevation map was used as a first guess.
In this way, a template to convert point data for river discharge into areal mean data of runoff depth was obtained from TRIP. One hundred eighty major rivers on the Earth are identified and fully resolved in TRIP; they cover 63 % of land, excluding Antarctica and Greenland. Most of the river basin sizes are well within a 20 % difference of published values. Furthermore, drainage areas for more than 300 gauging stations were delineated. Our analysis shows that the size of drainage area to each gauging station is successfully reproduced in TRIP.
The stream lengths in TRIP are shorter than the published ones. This is caused by meandering of rivers in the real world. Meandering ratio (rM), the ratio of actual (published) river length to river length on TRIP, has been defined and calculated. Averaged globally for all available data, rM is 1.4, and it is 1.3 for rivers with areas larger than 500,000 km^2. This information will be used in the design of the Scheme for Total Runoff Integrating Pathways (STRIP). In the present form, TRIP can be used as a template or for producing a time series of river flow using a simple version STRIP.
(Last updated at Wednesday, 28-May-1997 04:42:49 JST, by Taikan OKI)