On Monday 23 March 2020, the UK entered into a period of lockdown and restriction in a bid to reduce the spread of COVID-19 Coronavirus; with Ireland also implementing a full lockdown some 4 days later. 2 months on, it is now possible to analyse the impact of measures implemented by the UK and Irish Governments and highlight the benefits of what has been achieved in such a short timeframe. Images from across the world have been shared online to illustrate the environmental impacts that lockdown has achieved thus far, such as clearer canals in Venice and reduced smog in India.
Both Ireland and the UK have also realised the environmental benefits of lockdown, namely lower levels of air pollution in both urban and rural areas. Mayflower Smart Cities and Places is a smart city platform, designed by SSE Enterprise, that enables local authorities to monitor a range of variables through the integration of IoT sensors, applications and devices. Integrated smart devices include air quality sensors, weather stations, noise monitors and gully sensors, which can be connected through a variety of communication channels including cellular, LoRaWAN and Zigbee.
In Dublin and Southampton, smart sensors and devices are connected to the Mayflower lighting network using Zigbee, a wireless communication protocol, with data transferred from lighting network to the cloud using cellular communications. Mayflower Smart Cities and Places provides data visualisation and analytics at a variety of levels through its customisable drill-down dashboards.
Following the analysis of air quality monitoring data reported in Southampton and Dublin, SSE Enterprise have noted a consistent improvement in air pollution levels during the lockdown period. During the first month of lockdown, both Carbon Monoxide and noise levels have reduced, which can be attributed to reduced volumes of traffic flow, resulting from travel restrictions implemented by the UK and Irish governments.
Understanding the analysis
The predominant variable for the following air quality analysis is Carbon Monoxide. Carbon Monoxide (CO) is an odourless and colourless gas that is often a direct result of vehicle emissions and industrial activities, and in high volumes can be dangerous for both humans and wildlife. The natural concentration level of CO is approximately 0.2 parts per million (ppm). It is estimated that road transport is responsible for almost 90% of all carbon monoxide emissions in the UK (LondonAir, 2020).
Another variable used for air quality monitoring and reporting is Volatile Organic Compounds (VOCs). These are released into the air mostly during manufacture or use of everyday products and materials and are of concern as both indoor and outdoor air pollutants. In the outdoor environment, the main concern with VOCs is their role in the formation of ozone, a constituent of photochemical smog. Ozone can be harmful to health, particularly in children, the elderly, and people of all ages who have cardiovascular problems such as asthma or COPD. Ground level ozone can also have harmful effects on sensitive vegetation and ecosystems.
However, environmental pollution cannot solely be determined solely by air quality, as other pollutants must be considered when analysing the external environment, such as noise levels. LAeq is the A-weighted, equivalent continuous sound level in decibels measured over a stated period of time (T) and is easier to read on a display compared with instantaneous sound levels. This data is reported every 10 – 15 minutes in Dublin and provides an insight into the level of traffic noise along the Chapelizod Bypass.
Located on Brinton’s Road, the air quality monitoring device is positioned just 350m from Southampton Saints FC Stadium, a Premier League football ground subject to local traffic congestion on match days. The device may also be sensitive to Ocean Terminal cruise traffic and Southampton Airport traffic, both located within a 5-mile radius.
Lockdown restrictions were implemented by the UK Government on 23 March 2020, which included limiting travel to essential journeys only. CO levels during the first month of lockdown (period ending 24 April 2020) compared to the previous month when there were no restrictions (22 February – 22 March 2020) dropped by approximately 33%. During the same period, VOCs in Southampton dropped significantly by 73% compared with the previous month’s daily average level of VOCs.
The reduction of both VOCs and CO levels during this period contribute toward achieving the 4 key priorities outlined in Southampton City Council’s Clean Air Strategy (2019 – 2025): improve air quality in the city, supporting businesses and organisations, collaborating with communities and residents and promoting sustainability.
The Government of Ireland began to implement lockdown restrictions on 12 March 2020, with the closure of all educational and cultural institutions. By Friday 27 March 2020 the country had entered full lockdown – advising those with health conditions to shield in the home, closing down businesses and amenities, and banning all but essential travel.
The air quality sensor in Dublin is located on Chapelizod Bypass, just 200m from the busy Heuston train station, one of the largest train stations in Ireland. Within 10 miles of the air quality sensor are both Dublin Airport and Dublin Port, which handles almost 50% of all trade in the Republic of Ireland. In the same vicinity is a noise sensor, reporting both background and environmental noise data.
CO levels reported by the Chapelizod Bypass air quality sensor dropped by approximately 16% during the first month of lockdown (period ending 27th April 2020) in comparison with the month previous (27th February – 27th March 2020).
During this same period, there was also a consistent reduction in noise levels (LA10, LA90, LAeq and LAF_MAX) as shown in Table 1. This results in an average reduction of 4.5 dB across the range of noise monitoring measurables. LAF_MAX shows a reduction of 7.45 decibels between March and April 2020, which results in perceived sound volume being 1.7 times quieter. The consistent reduction of noise levels can potentially be attributed to lower levels of traffic along the Chapelizod Bypass during the first month of lockdown.
Table 1: Changes to Dublin noise levels in dB as a result of lockdown
Life after lockdown
As Government restrictions begin to relax, the long-term environmental impacts of lockdown are difficult to determine. SSE Enterprise continue to monitor changes to environmental data sets through Mayflower Smart Cities and Places as lockdown restrictions are adjusted.
The findings above of reduced CO levels and VOCs, and consistently lower LA values can be attributed to lower traffic volumes in these areas throughout the lockdown period. These provide a positive contribution to the environmental policies and objectives of both Southampton City Council and Dublin City Council, and it is likely these results will be indicative of air quality improvements across the UK during this time.
In the immediate term, we can only hope that as the lockdown is lifted, the adjustments made to everyday life provide additional environmental benefit and further opportunities to form the basis of air pollution improvement strategies and environmental policies of local authorities in the UK and the Republic of Ireland. This may result in a renewed focus on sustainable travel options such as encouraging Cycle2Work schemes and improving existing cycle paths to ensure the safety of commuters.
Prospective clients interested in learning more about Mayflower Smart Cities and Places and its capabilities are encouraged to contact SmartCities@sse.com for further information.