FOI request detail

Request for road transport and air quality data for studying correlations

Request ID: FOI-0109-2021
Date published: 01 May 2020

You asked

F/on from FOI-2145-1920 We have been working with the TFL data and found some interesting insights accepted for publication in a reputed conference. We are extending our study and it would be great if we could a bit more information around the timestamps of the emissions and concentration data collected available at: We are looking for the exact dates and possibly, times when each of these readings were made. Currently this information is missing in the data files. We are trying to understand various factors affecting pollutant concentration including weather conditions and it helps if we know the timestamps to look for this parallel complimentary data/information. Any help is greatly appreciated.

We answered

Our ref: FOI-0109-2021/GH

Thank you for your request received by Transport for London (TfL) on 22 April 2020 asking for information about air quality data.

Your request has been considered under the requirements of the Freedom of Information Act 2000 and our information access policy.

Unfortunately we do not hold the information you require. The air pollution concentration maps presented as part of the LAEI are not monitoring data but predictive modelling validated against local monitoring data in London.   You can access the monitoring data for London at the or via the air quality England website - both sites enable you to download hourly monitoring data across a wide range of pollutants.

The concentration modelling are provided as part of the LAEI are annual mean concentrations for the year 2016 - in that sense there is no time stamp on these data.  Similarly, the emissions estimates for sources are annual estimates of pollutants and do not represent a time series of emissions so as such there is no further specific date stamp on this data.

The Government has announced a series of measures to tackle the Coronavirus. It is essential for London, and in particular for all critical workers, that we continue to provide a safe transport network that enables them to make the journeys they need to.

In current circumstances, we are not able to answer FOI requests readily and we ask that you please do not make a request to us at present.

Answering FOI requests will require the use of limited resources and the attention of staff who could be supporting other essential activity. In any event, please note that our response time will be affected by the current situation.

If you are not satisfied with this response please see the attached information sheet for details of your right to appeal.

Yours sincerely

Graham Hurt

FOI Case Officer

FOI Case Management Team

General Counsel

Transport for London

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