Figure 1 . Influence of rainfall on channel profile form and
topographic metrics at steady state. a) Top row – left panel shows
river profiles adjusted to different amounts of spatially uniform
rainfall. Corresponding discharge accumulation curves are shown in the
middle panel. Right panel shows the relationship between mean rainfall
(defined as Q /A ) calculated at the outlet, with fluvial
relief (R ), ksn , andksn-q for a fixed uniform rock uplift rate. Note,
at steady state fluvial relief and ksn are
inversely related to mean rainfall, while ksn-qis independent of changes in rainfall. b) Bottom row – all panels as in
(a) but for a comparable suite of steady-state profiles adjusted to
spatially uniform rainfall, a decreasing upstream rainfall
(bottom-heavy) pattern, and an increasing upstream (top-heavy) pattern.
Note intersections that occur between profiles in the left panel and
middle panels, and that fluvial relief and ksnare positively related to mean rainfall in these cases (right panel),
inverted from (a). All other model parameters are equal (see Table 1).