Overestimates of Entrainment From Wetting of Aircraft Temperature Sensors in Cloud

Abstract

Temperature measurements from aircraft, taken with a reverse flow sensor and Rosemount probe, were compared in a penetration through a cloud to determine the effect of sensor wetting on the deduced entrainment. The temperature measured using the Rosemount probe was depressed relative to that measured with the reverse flow probe, leading to an underestimate of the equivalent potential temperature and an overestimate of the deduced entrainment. These results were used to identify possible errors in recent entrainment studies that used temperature as an indicator of entrainment.