ICOADS Web information page (Tuesday, 08-Nov-2005 17:00:22 MST):
Figure 3a. Numbers of observations (upper panel) and 2° boxes
(lower panel) of SST per month (1820-1859) used for the enhanced
statistics. The red curves show data before correction of the ZQ
problem, and the blue curves show data after the correction. Red
was plotted on top of blue, thus where red is not visible this
indicates that data for a given month were completely eliminated by
the ZQ problem prior to the correction. 2° boxes containing
one or more observations were counted; 2000 boxes represents about
17% of the maximum possible (i.e., classified as ocean or coastal)
global 2° boxes.
[Links to detailed][Report-rejection Problem]