Blue-carbon wetlands survive sea-level rise two ways: by building elevation through sediment and root accretion, or by migrating landward onto newly suitable ground. This 2D cross-section renders the same real cellular model as the 3D version — a cross-shore elevation profile where mean sea level rises over time, the vegetated growth band accretes and tries to keep pace, drowns at its seaward edge once it falls behind, and attempts to colonize new ground at its landward edge, but only up to a hard barrier you place, such as a seawall or coastal road. Push the barrier close to the shore and watch the marsh get squeezed to nothing even while accretion keeps working; pull it back and the same accretion rate lets the wetland track the rising sea indefinitely. Live readouts track the retained vegetated area, the sea-level rise so far, and the squeeze width — the newly suitable ground the barrier is blocking outright. Drag to pan along the profile and scroll or pinch to zoom in on the growth band.