Thin clouds at about 5 km altitude are more ubiquitous in the tropics than previously thought and they have a substantial cooling effect on climate. The cooling effect of mid-level clouds is currently missing in global climate models.

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Thin clouds at about 5 km altitude are more ubiquitous in the tropics than previously thought and they have a substantial cooling effect on climate. The cooling effect of mid-level clouds is currently missing in global climate models.