Figure 4
From: Indian Ocean corals reveal crucial role of World War II bias for twentieth century warming estimates
Western Indian Ocean coral and historical temperatures: WW II bias. (a) Western Indian Ocean (WIO) coral temperature reconstruction (magenta) compared with WIO ERSST321 (green) and ERSST49 (blue). (b) Same as A using HadSST222 and HadSST37,8. (c) Same as A using night-time marine air temperature (HadMAT119 and HadNMAT223). All time series are 21 point moving averages of bimonthly anomalies, and have been normalized to their standard deviation over the 1900–1995 period. Note different SST trend patterns during and after World War II depending on the SST product (black bar: time period of World War II bias). The WIO coral indicates large amplitude temperature anomalies during the late 19th century El Niño events of 1877/78 and 1896/97. See text for discussion.
