The Lancet Countdown UK case study

Studies on the benefits of tackling climate change abound. In The Lancet Planetary Health, the study by Martin L Williams and colleagues1 has the great merit of using large datasets to illuminate the possible health benefits of reducing greenhouse gas emissions. In the UK, the necessity to reduce emissions is enshrined in law through the 2008 Climate Change Act. Williams and colleagues rightly acknowledge that the Act was groundbreaking, positioning the UK as a world leader in reacting to climate change. By helping to decouple economic growth from carbon emissions, the Act has had an essential role in sending the UK on a more sustainable, prosperous course.2

By providing an estimate of the considerable health benefits from travelling further on this course (eg, 4 892 000–7 178 000 life-years saved from the reduction in nitrogen dioxide concentrations between 2011 and 2154 for two scenarios), the authors have done us a great service, highlighting the essential role the Act has, in this, its tenth year. But, as they point out, unintended consequences might arise, depending on the different policies adopted for decarbonisation. The promotion of diesel fuel in the 1990s—and the resultant air pollution problem—shows how the unintended consequences of well meaning policies can cause great harm, and potentially discredit our attempts to tackle climate change. This Article shows that even if vehicles became cleaner, projected increases in the number of vehicles and, crucially, journeys sees particulate matter air pollution increasing, resulting from factors include wear and tear of tyres.

It must be stressed that any potential unintended consequences of decarbonisation are likely to be avoidable and thus are not a necessary result of the Climate Change Act. The Act requires governments to attend, with urgency, to one of the most pressing problems—the need to decarbonise human activity so as to avoid increasingly dangerous climate disruption. Other policies need to identify and then address the unintended consequences.

A major virtue of this study is that it developed a method to tackle these unintended consequences—and is one that is transferable to assessments of the public health impacts of decarbonisation policies. In doing so, it affirms that capturing and analysing big data, with the specific intention of identifying unsuspected benefits or unwanted consequences, should be an essential component of any set of policies. Be realistic—demand the impossible was the slogan in the Paris of 1968, and using the method outlined in the study by Williams and colleagues offers policy makers the opportunity to embrace that wisdom.

The government could achieve its carbon targets in several ways, from accelerating the replacement of fossil fuels by renewable energy to incentivising walking and cycling over driving—many of which can have attendant health benefits.3 All demand good data combined with vision and strong guidance and support for those policy makers who will need to implement these policies.

These policies must also recognise the wider reality of environmental change. Aggregate human activity has pushed natural systems into unsafe operating spaces, threatening their stability.4 A prime example is soil, in which erosion is destroying our ability to grow enough nutritious food.5 Therefore, the modelling techniques used by William and colleagues’ study should be applied to the understanding of the health benefits of policies that act on a number of environmental fronts. In the case of soil, this application could include the potential benefits to health of more sustainable, regenerative agricultural practices, which also increase carbon sequestration and decrease nitrogen run off.6

The use of big data to reflect the financial consequences will be an important next step. Given the obsessive economic interest of policy makers, the system-wide economic benefits of policies will probably be the argument that has the greatest impact. Health professionals have an important role in promoting these policies, and are already creating groups, such as The Lancet Countdown and the UK Health Alliance on Climate Change, to facilitate this endeavour. In doing so, they would do well to support the method developed in Williams and colleagues’ study, and to push for more action like that spurred by the UK Climate Change Act.

This article was originally published by The Lancet Planetary Health and was co-written with Dr Robin Stott.


1ML Williams, N Kitwiroon, D Dajnak, et al.The Lancet Countdown on health benefits from the UK Climate Change Act: a modelling studyLancet Planet Health, 2 (2018), pp. e202-e213ArticleDownload PDFView Record in ScopusGoogle Scholar2Committee on Climate ChangeMeeting carbon budgets: closing the policy gap. 2017 report to parliament, Accessed 3rd Apr 2018Google Scholar3J Hosking, P Mudu, E Fletcher[2011] Health co-benefits of climate change mitigation: transport sector;jsessionid=0D3380F856F8B4B935D454CE0E23B9A2?sequence=1, Accessed 4th Apr 2018Google Scholar4J Rockström, W Steffen, K Noone, et al.Planetary boundaries: exploring the safe operating space for humanityEcol Soc, 14 (2009), p. 32View Record in ScopusGoogle Scholar5N Watts, WN Adger, S Ayeb-Karlsson, et al.The Lancet Countdown: tracking progress on health and climate changeLancet, 389 (2016), pp. 1151-1164Google Scholar6FAOSoil carbon sequestration: SOLAW background thematic report–TR04B, Accessed 4th Apr 2018Google Scholar