Introduction to Openair
Openair provides free, open-source and innovative tools to analyse, interpret and understand air pollution data using R; a free and open-source programming language designed for the analysis of data. The Openair tools available on this website can be used to readily perform complex and innovative analysis of current and archived air pollutant data from the Welsh Air Quality Database, allowing powerful data visualisation and interrogation capabilities for this data for the first time. This website makes it straightforward to download these graphical outputs from Openair in document ready formats.
The Openair package was primarily developed for the analysis of air pollution datasets with the ability to handle high volumes of data; the Welsh Air Quality Database, with its long data record lends itself to this. A further strength of the Openair tools is that they also allow data to be conditioned by one or more variables. For example, plots can be produced that show the inter-relationships between air pollutants and meteorological parameters, or temporal trends which vary over different time periods such as hour of day, day of week, month of year, and so on, that would otherwise not be apparent.
The Openair website contains a full description of all functions as well as downloads and guidance to help users apply the tools to their own data. Air Quality in Wales provides simplified web access to a customised selection of the Openair tools, updated to include recent developments in Openair including tools that require meteorological data in order to run. To implement tools requiring meteorological data, modelled wind speed and wind direction data generated for the UK air quality forecast (PDF) has been made available along with the measured air pollutant data.
The online tools make analysis and review of automatic data from the Welsh Air Quality Database using Openair possible without the need to install and maintain both R and Openair locally. For users that do desire full control over their analysis and output quality/format, we recommend installing R and Openair locally and obtaining data as Rdata objects from this website. In this way, the user can select and preview the desired data using the online tools prior to downloading it for further analysis in the R environment.
Please Note: The modelled weather data provided on the Air Quality in Wales website for use with the Openair tools have been created under the Defra & Devolved Administrations UK air quality forecasting contract. The model data are updated daily.
A 10 km x 10 km grid resolution is used for modelling UK meteorological conditions for air quality forecasting. This means that the data are representative of regional synoptic conditions at the location of each UK air quality monitoring site, but do not account for any details of the local site environment. The data should therefore be used with caution in any local data analysis or modelling studies. However it does provide an alternative to measured meteorological data that is often located a large distance from the AQ monitoring site.
Any use of these data is at the users own risk and should be made in accordance with the terms and conditions of use of this website.