The occurrence of cirrus clouds associated with eastward propagating equatorialn = 0 inertio-gravity and Kelvin waves in November 2011 during the CINDY2011/DYNAMO campaign

[1] Cirrus cloud variability associated with n = 0 eastward inertio-gravity equatorial waves and equatorial Kelvin waves (both with the period of ~4 days) and equatorial Kelvin wave with another periodicity (~16 days) were observed in the tropical Indian Ocean (8.0°S, 80.5°E) in November of 2011 during the Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011 (CINDY2011)/Dynamics of the Madden-Julian Oscillation (DYNAMO) field campaign using balloon-borne cryogenic frostpoint hygrometers, Vaisala radiosondes, and a shipborne high spectral resolution lidar system. During early to mid-November, the cirrus cloud appearance corresponded primarily with high supersaturation and high relative humidity caused by the temperature disturbances associated with the ~4 day waves between 12 km altitude and the cold-point tropopause. The cirrus clouds disappeared under the unfavorable (downward wind and dry) conditions that were caused by the ~4 day waves, although the ~16 day wave was generating favorable conditions. Our multi-instrument cirrus measurements revealed that we must consider the phases of various overlapping waves when estimating dehydration efficiency caused by cirrus clouds around the cold-point tropopause.