Consider the following characteristics of a tropical cyclone : 1. A warm sea temperature of > 26°C 2. High relative humidity of atmosphere at a height of > 700 m 3. Atmospheric instability The above mentioned characteristics are associated with which one of the following cycles of its development ?

The characteristics described—sea surface temperatures (SST) exceeding 26°C, high relative humidity in the mid-troposphere (700 hPa), and atmospheric instability—are the fundamental prerequisites for tropical cyclogenesis [2]. These thermodynamic factors are essential for the formulation and initial stage of a tropical cyclone, providing the necessary latent heat and moisture to fuel deep convection. Specifically, SSTs above 26°C provide the thermal energy required for the initial disturbance to intensify. High humidity at the 700 hPa level (approximately 3000 m, though initial moisture surges are noted lower) prevents the evaporation of clouds and entrainment of dry air, which would otherwise inhibit the growth of the nascent storm [2]. Once these conditions align, a tropical depression can develop into a self-sustaining system, marking the transition from the formulation stage to intensification.

Sources

1. [2] https://www.aoml.noaa.gov/hrd/Landsea/ClimateChange&TCs.pdf