Making air quality indices comparable – assessment of 10 years of air pollutant levels in western Europe

To address the incomparability of the large number of existing air quality indices, we propose a new normalization method that is suited to directly compare air quality indices based on the common European World Health Organization (WHO) air quality guidelines for NO₂, O₃, and PM₁₀. Using this method, we compared three air quality indices based on the European guidelines, related them to another air quality index based on the relative risk concept, and used them to assess the air quality and its trends in northwest central Europe. The average air quality in the area of investigation is below the recommended European guidelines. The majority of index values exceeding this threshold are caused by PM₁₀, which is also, in most cases, responsible for the degrading trends in air quality. Eleven out of 29 stations tested showed significant trends, of which eight indicated trends towards better air quality.

针对当前大量空气质量指数(Air Quality Indices)缺乏可比性的问题，本文提出一种全新的归一化方法，可基于世界卫生组织（WHO）欧洲区域针对二氧化氮(NO₂)、臭氧(O₃)及可吸入颗粒物(PM₁0)制定的通用空气质量指南，直接对各类空气质量指数开展对比分析。借助该方法，本文对3套基于欧洲指南的空气质量指数进行了对比，将其与另一套基于相对风险概念的空气质量指数相关联，并以此评估了欧洲中西北部地区的空气质量及其变化趋势。研究区域的整体空气质量平均水平低于欧洲指南推荐的限值。多数超出该阈值的指数值由可吸入颗粒物(PM₁0)导致，且在大多数情况下，空气质量的恶化趋势也与之密切相关。在所测试的29个空气质量监测站点中，有11个呈现出显著的变化趋势，其中8个指向空气质量的改善。