Fungal cells usually die when they travel through the atmosphere due to the desiccating effects of higher altitudes. However, some particularly resilient fungal bioaerosols have been shown to survive in atmospheric transport despite exposure to severe UV light conditions. Although bioaerosol levels of fungal spores increase in higher humidity conditions, they can also be active in low humidity conditions and in most temperature ranges. Certain fungal bioaerosols even increase at relatively low levels of humidity.