Firns are compacted, granular snows that are found in high altitude regions. These snows are important for the formation of glaciers as they accumulate over time. Synonyms for the term firns include snowfields, glacier ice, frost, ice crystals, and hardened snow. Other related snow terms include avalanche, snowdrift, blizzard, powder snow, and sleet. These terms are often used to describe different types of snow conditions, and are important for determining the risks associated with outdoor activities in snowy areas. Understanding the different types of snow can help individuals stay safe and make informed decisions when exploring snowy environments.