Cyclone-cyclone interactions through the ocean pathway

Abstract

The intense sea surface temperature cooling caused by tropical cyclone-induced mixing lasts several weeks and may thus influence a later cyclone passing over it. Using a 28 year analysis spanning the North Atlantic, eastern Pacific, and Northwest Pacific, we systematically demonstrate that, on average, when tropical cyclones encounter lingering wakes, they experience sea surface temperatures that are ∼0.25-0.5°C colder. Consequently, the intensification rates are ∼0.4-0.7ms-136h lower for cyclones when they interact with wakes, consistent with the maximum potential intensity theory. The probability for cyclones to encounter lingering wakes varies positively with cyclone frequency, is ∼10% on average, and has been as high as 27%-37% in the past. These large interaction probabilities reduce the mean intensification rates for cyclones by 3%-6% on average and by ∼12%-15% during the most active years. "Cyclone-cyclone interactions" may therefore represent a mechanism through which tropical cyclones self-regulate their activity to an extent on intraseasonal time scales. Key Points Cyclones encounter more lingering wakes with increasing cyclone frequencyCyclone-cyclone interactions reduce the mean cyclone intensification ratesCyclones may self-regulate their activity on intraseasonal time scale