A new method called the Modified Band Approach was used to calculate how sunlight breaks down chemicals in the air in a global model. This method improved the accuracy of the calculations, showing big changes in the amount of ozone and other important gases in different parts of the atmosphere. The increase in ozone in the northern hemisphere makes the air cleaner and reduces the lifetime of harmful gases like carbon monoxide and methane. The model also better matches real-world observations in Europe during winter, especially in areas with high nitrogen oxide pollution.