Fig. 1

Annual dry season intensity at Barro Colorado Island, 1931–2015, estimated as the extreme cumulative water deficit each year, starting from any day after 30 September. Annual deficits (black points) are presented as negative numbers, so a harsher dry season is more negative (lower on the graph). The curve gives the 5-year running average deficit. The mean water deficit was -508 mm (shown with an horizontal gray line), and the SD was 94 mm. All dry seasons more than 1 SD drier (below) the mean are shown with red points. The vertical dashed lines mark each census of the 50-ha plot, and the mean dry season deficit during each census interval is shown as a horizontal blue line between the dashed lines. The two driest census intervals were in the 1980s; every interval since has been wetter than the long-term average