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3. RiverGIS Processes

3.1. Developing Simulated Networks

3.1.1. Creating Initial Routing

Generation of STNnetwork from flow accumulation grid and flow direction grid
(process used for generation of Gulf of Maine 1 min STNnetwork)
Data used - Hydro1k

1) Creation of sub -basin grid to guide STN development from flow accumulation grid.

-In RGIS:
1) IMPORTed Lambert projection flow direction grid (hydro1k dataset)
2) Created Virtual Station Locations using ANALYSE->STATION LOCATION subbasin area = 50 km2, tolerance = 10%
3) LINKed virtual station coverage to network
4) Ran STN CHARACTERISTICS for station coverage
5) Ran SUBBASIN function to create grid of subbasins associated with stations

 -EXPORT subbasin grid to arcinfo
-Project in geographic coordinate system
-EXPORT geo_subbasin grid to RGIS

2) Resampling of Flow Accumulation grid to preserve flow values (ArcInfo)

g_fa15sec=project(g_fawin,na_lanbert_geo,nearest,[calc 0.25/60])
g_05sec=project(g_fawin,na_lambert_geo,nearest,[calc 5/3600])

remove arc_insterted null values
g_fa15secwin=setnull(g_fa15sec == 0, g_fa15sec * -1)

aggregate flow accumulation to imin resolution, keeping high values

g_Fa1min = aggregate(g_fa15secwin,4,min)

(for 5sec) g2_fa1min = aggregate(g_05secwin,12,min)

gridascii g_fa1min

import to RGIS

3) Link subbasin to flow accumulation grid, CREATE NETWORK

Edit network if necessary to remove fragmented basins (partial river networks).

3.1.2. Editing flow direction

3.1.3. Background data

3.2. Basin Statistics

3.2.1. Continuous Grid Statistics

3.2.2. Continuous Grid Histograms

3.2.3. Discrete Grid Histograms

3.3. Subbasin Statistics<

3.3.1. Continuous Grid Statistics

3.3.2. Continuous Grid Histograms

3.3.3. Discrete Grid Histograms

3.4. Miscellaneous