Guidelines for continuous measurements of ozone in the troposphere

This document provides detailed guidance on the best practices in use for tropospheric ozone measurements. The focus is on continuous in-situ measurements of ozone in the troposphere, performed in particular at continental or island sites with altitudes ranging from sea level to mountain tops. The purpose of this report is to contribute to a convergence of these practices world-wide in the interest of promoting the principles and objectives of the GAW Programme, in particular to establish a harmonized global data set of tropospheric ozone measurements. While the report's primary focus is the consolidation of ozone measurement practices within the GAW Programme, authors believe that many aspects covered in the following sections are also relevant for observations from other platforms (e.g. aircraft), and that they may be useful for improving regional air quality networks, particularly in countries with little experience or limited resources.