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The Cloud Profiling Radar (CPR) detecting efficiency on low-level clouds is affected by many situations, including surface clutter, spatial resolution, and radar sensitivity. These factors can uniquely or jointly result in missed detections of oceanic single-layer warm clouds. Fifty-seven percent of missed detections are attributed to a single factor, and the rest are attributed to two or more factors that are indistinguishable. For missed warm clouds above 1km, 30% result from the nonovercast effect, while the CPR range resolution is the major cause for the overcast ones. In particular, 18.4% are attributed exclusively to specific cloud microphysics, which is characterized by droplet effective radius (DER) and cloud optical thickness (COT). Compared to COT, the CPR detection is more dependent on DER, with a critical value standing around 10m. It is only for larger DER that the effects from COT turn to arise. Given liquid water path, clouds with larger DER and smaller COT are more likely to generate sufficient reflectivity and be detected than their counterpart. For clouds with the same DER and COT, opposite detecting results are primarily determined by the different droplet size distributions that lead to a variable reflectivity across the CPR detecting limit. Over global oceans, total miss rate of cloud occurrences approaches 0.73, while the loss rate of cloud water mass is 0.42 due to the smaller liquid water path of CPR-missed clouds. The CPR-missed detections also lead to uncertainties in cloud radiative forcing estimations. A notable overestimation of shortwave cloud forcing at 160% is found at bottom and top of atmosphere.

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