Figure 2 . Schematic illustration of key aspects of complex transient responses – defined in section 3.3 – that can result from changes to a relatively bottom-heavy (a) or a top-heavy rainfall gradient (b) – rainfall shown in inset. Horizontal grey bars highlight resulting net change in fluvial relief (ΔR ) and maximum elevation change (Δzsc ­) along the center of the profile. Colored circles mark positions ofxsc (yellow) and xzc (red) that also demarcate segments of net divergent and convergent transient adjustments – see text for definitions and discussion. Net modes of transient adjustment are indicated along top axis. Note reversal at position xzc (net incision downstream, net uplift upstream); however, during transience, adjustment upstream ofxsc is variable with time. Inset shows both local rainfall rate (P , blue) and upstream averaged rainfall (\(\overline{P}\), black). P = \(\overline{P}\) for spatially uniform rainfall; only P is depicted for initial rainfall. Positions of xsc andxzc ­ in inset correspond to those along the profiles in the main figure. Note along-stream offset in position where P and \(\overline{P}\) exceed the initial rainfall rate, the latter corresponding tosc ­. Also, note that the difference between P and \(\overline{P}\) increases systematically downstream.