Conducting PhD vivas online is working fine: there will be no need to return to excessive flying habits

In this blog, Bethan Cornell, a Physics PhD Student at King’s College London who is undertaking an internship at HEPI, explores how a small change could have a big positive impact.

World Earth Day has been a timely reminder of the global climate crisis. If we are to meet the UK’s emissions target of net zero by 2050 then all organisations must think seriously about the steps they can take to play their part. In their blog yesterday, Stephen Allen and Matt Watson discussed the strategies that universities could use to reduce their emissions from academics flying. While these are important and necessary, they are also bold and will require a significant culture change.

There are some simple changes that universities could make to reduce their emissions while having little to no negative impact on business as usual, even with the possibility of gains alongside greenhouse gas emission reductions. One example has become apparent during the current pandemic – conducting PhD vivas online.

A PhD viva is the final oral exam that doctoral research students must take to defend their thesis. It involves an in-depth interview with both an internal and external examiner, both experts in the student’s field of research who have never previously worked with the student. In narrow research communities these criteria are not always easy to meet, which often results in external examiners travelling from institutions a long distance from the student’s home university and, not infrequently, flying in from abroad. Since travel restrictions have been imposed in Europe, face-to-face PhD vivas are no longer possible and they are instead successfully taking place using video conferencing software such as Zoom.

According to data from HESA, in 2018/19 there were 37,120 first-year PhD students in the UK. Three years from now, roughly this number of PhD vivas will occur in UK universities. Currently, there are no accurate publicly available records kept on the number of external examiners that travel long distances for vivas. So, in order to gauge the effects of moving external examiners online only, I have made some conservative estimates:

• 1 per cent of external examiners fly in for PhD students’ vivas in the UK; • the flights are on average the distance between Hamburg and Manchester, around 500 miles; and
• 40 per cent of external examiners travel via train in the UK, the equivalent distance of Edinburgh to Newcastle, around 125 miles.

Within these estimates, this would equate to 389 tonnes of carbon, according to a simple online carbon footprint calculator. On the basis that one tree offsets seven tonnes of carbon and the average UK resident uses 10 tonnes a year, then this is the same as planting 56 trees and negating the impact of 39 people for a year. Of course, the problem still remains that a lack of record keeping makes it impossible to currently asses how accurate these figures are. Although based on anecdotal evidence, this is a conservative estimate. The real figures could be closer to:

• 10 per cent of external examiners flying the distance of Hamburg to Manchester; and
• 60 per cent taking the train the equivalent distance of Edinburgh to Newcastle.

This would equate to 1,373 tonnes of carbon, which is 137 average people or 196 trees. According to HESA, this is 32% of the University of Bedfordshire’s total scope one and two carbon emissions for the year 2017/18 and 4% of the University of Sheffield’s equivalent emissions in the same year.

The UK Carbon footprint is around 781 million tonnes of carbon. So, by keeping vivas online, a system which we know works very well and is already implemented across most institutions due to Covid-19, universities in the UK might help to reduce the National carbon footprint by 0.0002%.

This might not sound like a lot, but it is only one tiny, easy change. Given the UK’s world-leading position in PhD training, it may also inspire universities across the globe to follow suit – in which case the impact would be far greater.

In performing these ‘back of an envelope’ calculations and reflecting on the content I have seen over the past two days, I have learnt two things:

1. UK universities should keep better data on staff and examiner travel so that they can properly assess their carbon emissions; and
2. If they do assess their carbon emissions, then universities may be very pleasantly surprised about the cumulative gains they will make from implementing many small and easy changes.