A multitude of consequences from global warming and environmental pollution can already be seen for nature and humans. The continuous burning of fossil fuels leads to rising temperatures and rising water levels causing extreme weather phenomena like heat waves and flooding. Increasing levels of air pollution also cause adverse health effects. This is especially important for pollen allergy sufferers because air pollution plays a central role in the interactions between pollen and humans. Today, pollen allergy sufferers are confronted with longer pollen seasons and pollen with potentially increased allergenicity. The effects for pollen allergy sufferers are an increased duration and severity of symptoms. New research results from the Medical University of Vienna prove that out of the most important air pollution parameters (particulate matter, nitrogen dioxide, sulfur dioxide, and ozone) especially ozone causes increased symptom severity in pollen allergy sufferers during the birch, grass, and ragweed pollen seasons.