Final answer:
Volcanic aerosols, particularly sulfur dioxide, are the main contributors to global cooling events following an eruption, reflecting sunlight and causing 'haze-effect cooling'.
Step-by-step explanation:
The aspect of volcanic eruption most strongly linked to global cooling events, which may last several years, is the release of aerosols, primarily sulfur dioxide (SO2), into the atmosphere. Eruptions eject fine particles that can reflect sunlight, reducing the amount of solar radiation reaching the Earth's surface.
For instance, the eruption of volcanoes in Iceland in 1783 released large volumes of sulfur dioxide, causing 'haze-effect cooling' that led to significantly lower average winter temperatures in Europe and North America. Similarly, the 1991 eruption of Mount Pinatubo ejected SO2 aerosols, resulting in a global temperature decrease of 0.4 °C. The Krakatoa event in 1883 also had a substantial cooling effect on global temperatures, which were affected for up to five years post-eruption.