What factor primarily caused the temperature rise during the End Triassic extinction?

The primary factor that caused the temperature rise during the End Triassic extinction was indeed volcanic eruptions. During this period, extensive volcanic activity, particularly related to the Central Atlantic Magmatic Province (CAMP), released massive amounts of carbon dioxide and other greenhouse gases into the atmosphere. This influx of gas led to a significant increase in atmospheric temperatures, disrupting climate patterns and contributing to the extinction event.

The volcanic eruptions not only caused direct environmental changes, such as ash fallout and acid rain but also had long-term effects on the climate by altering global carbon cycles. The resulting temperature rise would have created stress on ecosystems, leading to widespread extinction among various species, particularly those that were unable to adapt to the rapidly changing conditions. This makes volcanic eruptions the most significant factor associated with the temperature rise during the End Triassic extinction.