Due to time lags in moving energy / heat around, there is no reason to think that deeper ocean temperature changes will be in lock - step with surface changes. (skepticalscience.com)
... which is further emphasized by the sharp - edged surface change on the rear fascia. (automobilemag.com)
The company's indicators feature a visual signal, identified when the active surface changes color, when exposed to too much heat or if it is frozen. (fooddrink-magazine.com)