Fig. 4

JJAS mean cloud cover fraction (%) at different atmospheric levels. (a–c) Low-level, mid-level, and high-level cloud cover, respectively, from ISCCP. (d–f) Biases in DefCAM5 relative to ISCCP for each cloud level. (g–i) Biases in DtauCAM5 relative to ISCCP. (j–l) Differences between DtauCAM5 and DefCAM5. In panels (j-l), blue (red) hatching indicates statistically significant bias reduction (increase) at 95% confidence level, based on a two-tailed Student’s t-test.