Biological thermoreception extends beyond mere temperature detection, capturing nuanced cues such as sunlight, wind chill, humidity, and object contact. However, artificial thermoreceptors rarely match the acuity and perceptual richness with their biological counterpart, leaving a critical gap in thermosensory functionality for human-machine integration. Here, we introduce a structurally programmed iontronic platform that leverages energy landscape engineering in a heterogeneous polymer electrolyte to establish a continuous distribution of potential wells hosting a continuum of ionic carrier states. This architecture enables semiconductor-like thermally activated conduction by ionic carriers, achieving detection of temperature variations as small as 8 mK. Building on this platform, we develop a biomimetic ionic skin that interprets airflow, humidity, solar irradiation, thermal conductivity variations, and evaporative cooling through thermal cues, mirroring the multifaceted thermoreception of biological skin. This work complements the existing research paradigm of iontronics by integrating solid-state physics principles. The artificial thermoreceptor thus narrows the gap between artificial and biological thermosensation, advancing human-machine integration and biohybrid systems.