Ozone impact from solar energetic particles cools the polar stratosphere

Both are necessary to understand links between EPP and regional climate variability. Here we use a chemistry-climate model to assess the importance of EPP on late winter/spring polar stratosphere.

In transient simulations, the impact on NOy, ozone, and temperature is underestimated when using EPP forcing from the current recommendation of the Coupled Model Intercomparison Project (CMIP6). The resulting temperature response is largely masked by overall dynamical variability. An idealised experiment with EPP forcing that reproduces observed levels of NOy results in a significant reduction of ozone (up to 25%), cooling the stratosphere (up to 3 K) during late winter/spring.