At different latitudes Φ, the angle between gravity and the rotation axis (i.e. the colatitude 90°-Φ) changes correspondingly. This latitude variation significantly impacts heat transport and flow dynamics across geophysical and astrophysical systems. However, previous experimental studies have primarily focused on the polar regions (Φ=90°). Here we present results from a novel experiment that allows the latitude Φ to be varied from 10° to 90°. In the experiment, water was used as the working fluid (Pr=4.3), and measurements were made at two Rayleigh numbers (Ra=3.3e7 and 1.3e8). It is found that, compared to the polar regions, the heat transfer efficiency in the low-latitude regions can be significantly enhanced at certain Rayleigh numbers and dropped sharply at others, which are consistent with previous observations and numerical simulations. We also observed that the Nu-Φ relationship at fixed Ra is strongly modulated by the Ekman number (Ek).

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