| Authors | Louisa Kramer, Hannah Walker, Jack Davison |
| Compilation date | 26 January 2026 |
| Customer | London Borough of Camden |
| Approved by | Tim Bevington |
| Copyright | Ricardo |
| EULA | http://ee.ricardo.com/cms/eula/ |
| Contract reference | ED79001 | Report reference | 26 |
This is a summary report for London Borough of Camden for the period Monday January 19 2026 to Sunday January 25 2026.
It shows up to date provisional monitoring data and presents a simple summary of the current concentrations in the context of recent weather patterns and anticipated short term weather. It can be used by the Local Authority to monitor current levels, understand and explain any recent episodes and to subjectively forecast and act on the potential for evolving episodes.
This is a dynamic report containing embedded data from which the report tables, plots and graphs are generated. The embedded data allows the reader a level of interaction with some of the report findings, providing additional insight. This approach enables a more easily navigated and streamlined report providing an engaging and intuitive reader experience.
Maps for example can be panned and zoomed with different layers and markers turned on and off and with popup information by clicking on markers or hovering the mouse over them. Tables may contain much more information than initially displayed and can be set to show different numbers of rows, and can be filtered sorted or searched to display only specific information of interest. Some time series plots can be tracked with the mouse cursor to obtain specific time/date stamps and values and the reader can zoom into a specific time window by dragging with the cursor and double left clicking to return to the full plot extent.
The report is easily navigable using the floating table of contents on the left pane which tracks with the reader’s progress through the report and expands and collapses to a level of detail related to the subheadings used. The layout of the report is also dynamic, with some sections split into specific ‘tabs’ (e.g. per pollutant or per site) for ease of access to those sections.
A summary of site information is presented in the below map and table.
The below map can be zoomed in and out of by using your mouse scroll wheel, or using the widget at the top-left. A satellite view can be toggled on and off using the menu at the top-right. Clicking on individual markers will show the name of the site and the pollutants it measures and, if available, a link to further information.
Clicking on the headers of these tables will sort them. The whole tables can also be searched by using the box at the upper-right. Clicking on the site names will expand to show information about individual pollutants.
Data contained within this report is managed by Ricardo and stored in a dedicated, secure database. This report was generated using the data available at the time of compilation (8 am on Monday January 26, 2026). This data is provisional and subject to change, and as such should be treated with caution.
Gaseous pollutant mass units are at 20 °C and 1013 mb. NOx mass units are NOx as NO2 μg m-3. Particulate matter concentrations are reported at ambient temperature and pressure.
The European Air Quality Directive and Fourth Daughter Directive set out legal limits for different pollutants as Limit Values, Target Values or Long Term Objectives to protect human health. With the UK’s exit from the EU the UK’s Air Quality Strategy (AQS) is no longer tied to that of the EU, however the current objectives are at least as stringent as the EC limit values.
Legal limits for different pollutants in the UK are set out in the Air Quality Standards Regulations 2010. The Limit Values and Target Values for Scotland and UK (Except Scotland) and England and Wales and Scotland and Northern Ireland and England are summarised in the table below. Local authorities don’t typically measure ozone, benzene, B[a]P or metals that are captured within Defra’s national networks. All pollutants measured have been included in this data summary for completeness, irrespective of their significance for local authority policy interests.
The below two tabs contain summary statistics for the reported collection of measurement sites. “Cumulative Statistics” contains all data from the beginning of the year up until and including the reported period, whereas “Weekly Statistics” contains data for only the reported period.
The below tables can be sorted by clicking on the column headers. The ‘search’ box at the top-right can also be used to filter the table.
The following tables present pollutant statistics for the period from the start of the year to the end of the reported week. The Low, Moderate and High indicate the number of days for a particular pollutant when the concentrations are in the corresponding AQI bands from the beginning of the year until the end of the reported week.
The following tables present weekly pollutant statistics for the reported week. For public data, these statistics will match those made available on UK-air, and/or Air Quality England. The Low, Moderate and High indicates the number of days for a particular pollutant when the concentrations are in the corresponding AQI bands during the reported week.
The plots below show the time series of concentrations in 2026 so far. Each pollutant is presented on a different tab and all sites are shown on each plot for comparison. By default the period from 01 January 2026 to 25 January 2026 is shown, but the rest of the time series can be revealed by interacting with the plots.
Holding the mouse over the lines will highlight specific values and time stamp for that record for each station. Clicking on the legend will toggle on and off specific traces, and double clicking on it will isolate single traces. These plots can be zoomed in a similar way to other interactive plots, although the range-slider at the bottom of the plot can also be used to examine a specific time period of interest.
The table presented below shows summary statistics for the week. Please note, these data are provisional and subject to change.
The table below shows the tabulated hourly measurement data for the reported week. Please note that these data are provisional and subject to change.
Click on a site in the below table to reveal the hourly values within. The table can be sorted by clicking on the column headers. The ‘search’ box at the top-right can also be used to filter the table.
The back trajectory plot shows data from the HYSPLIT forecast model (NOAA HYSPLIT). This shows the air mass back trajectories for the previous day (2026-01-24), the trajectory for the current day (2026-01-25) and the forecast for the coming days.
Some examples of air mass origins and their impact on measured concentrations are described below:
When trajectories demonstrate strong winds (long gaps between markers) this generally (but not always!) suggests effective dispersion of local emissions. When the markers are closer together this generally represents lower wind speed which might be responsible for poorer dispersion and the accumulation of pollution from local emissions sources.
Strong winds can represent increased long range transport of pollutants. For example, trajectories that extend over the Sahara can indicate transport of African dust to the UK and air masses which originate from Russia can transport primary particles from Russian forest clearance and burning to the UK.
When trajectories extend far out over the Atlantic Ocean where there are no sources (except perhaps sea salt particles), the concentrations of pollutants measured in the UK are expected to be low.
In the UK during anti-cyclonic (high pressure) conditions, the trajectory lines are often tightly curled, close together and represent low wind speed recirculation of air. This kind of stagnation episode is characterised by increased concentrations.
When trajectories extend over other land masses (e.g. Europe) there is potential for transboundary pollution like particles and ozone or ozone precursors to be imported to the UK. During spring time (typically March), sustained winds from the continent can produce secondary aerosol episodes seen as elevated PM2.5 concentrations (and finer fractions) associated with emissions from agriculture. Generally, by late April, temperatures are high enough that the ammonium nitrate responsible breaks down in the atmosphere before concentrations accumulate.
The animation and daily forecast bar below show the weather forecast for the coming days. The animation is interactive: press the play button at the bottom of the animation to view the animated forecast. Hover the cursor over the animation and a bar to the right hand side will appear. From this bar the user can select to view the forecast wind speed and direction, cloud cover, temperature, rain, waves or pressure. This weather forecast is sourced from Windytv and is the current forecast for the day at which this document is viewed (and therefore is directly relevant at the time the report is provided but which will not refer to the period that monitoring data covers if viewed at a later time).
| Name | Tim Bevington |
| Address | Ricardo, Gemini Building, Harwell, Didcot, OX11 0QR, United Kingdom |
| Telephone | 01235 753125 |
| tim.bevington@ricardo.com |