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Why was there no polar ice during the Triassic Period?

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Triassic paleogeography — Triassic Period Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the early Triassic Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.

During the Triassic Period, the Earth experienced a significantly more homogeneous climate than it does today, characterized by a lack of polar ice.1

The absence of polar ice is attributed to the reduced temperature gradient between the Equator and the poles, which prevented the extreme cold necessary for the formation of permanent ice caps. This climatic state was influenced by the existence of the supercontinent Pangea, which dominated the global geography. The large size of the surrounding ocean, Panthalassa, likely facilitated relatively simple oceanic circulation patterns, consisting of massive gyres that helped distribute heat across the globe.12

While the early Triassic was marked by widespread aridity, the climate shifted toward a monsoonal climate in the Middle and Late Triassic, bringing seasonal precipitation to many regions. The presence of coal deposits in high-latitude areas, such as Antarctica and Arctic Canada, further indicates that these regions experienced humid, temperate conditions rather than freezing, icy environments.1