Interview with Prof. Jean-Pascal Van Ypersele, Climate scientist and Vice-Chair of IPCC (Intergovernmental Panel on Climate Change)
This article was initially published in Public Transport Trends 2015.
Prof. van Ypersele, IPCC published in 2014 its Fifth assessment report on climate change. What are the experts’ main messages to the world?
The four key messages are the following:
1. Human influence on the climate system is clear;
2. Continued emissions of greenhouse gases will increase the likelihood of severe, pervasive and irreversible impacts for people and ecosystems;
3. While climate change is a threat to sustainable development, there are many opportunities to integrate mitigation, adaptation and the pursuit of other societal objectives;
4. Humanity has the means to limit climate change and build a more sustainable and resilient future.
How is the climate evolving? What are the main trends?
Global mean temperature has increased by almost one degree Celsius since 1900, most glaciers are melting, and average sea level has increased by almost 20 cm since 1900. Since 1950, extreme hot days and heavy precipitation events have become more common. Climate is really changing.
Do you see signs of hope?
Yes, most policy-makers are now aware of the climate challenge, and many are starting to implement measures to address it. As adaptation and mitigation projects get under way, many realise that these projects can deliver co-benefits in other areas (reduced traffic congestion and air pollution, innovation, job creation, development, etc.): this helps to build momentum.
Human activities and habitats are more and more concentrated in urban areas. What should be done at the city level?
In rapidly growing and urbanising regions, mitigation strategies based on spatial planning and efficient infrastructure supply can avoid the lock-in of high-emission patterns. Mixed-use zoning, transport-oriented development, increased density and co-located jobs and homes can reduce direct and indirect energy use across sectors. Building resilient infrastructure systems can reduce the vulnerability of urban settlements and cities to coastal flooding, sea-level rise, and other climate-induced stresses.
The development of motorised transport is part of the climate problem. What advice would you give to urban decision-makers about their transport policy?
Think ahead, particularly in developing countries, so that lock-in effects are avoided. Once infrastructure has been built without thinking about public transport, bicycles and pedestrians, it is often very difficult to adapt this infrastructure later. That leaves a transportation system reliant exclusively on cars, which tend to saturate any available space. Traffic jams have huge costs for everyone, and public transport has a key role to play to improve living conditions and fight climate change.
Carbon pricing is a tool for guiding the efforts of industry. Does this work?
Yes, it works. For example, the IPCC reports that tax-based policies specifically aimed at reducing greenhouse gas (GHG) emissions – alongside technology and other policies –have helped to weaken the link between GHG emissions and GDP (gross domestic product).
What are the effects of low oil prices on climate change?
The IPCC noted that positive oil price trends can provide strong economic incentives for consumers to adopt mitigation measures. So lower prices, if they remain low, could decrease the use of such measures. On the other hand, governments could use this opportunity to decrease fossil fuel subsidies and implement carbon-pricing policies (while compensating for possible social effects).
In December 2015, the Conference of the Parties (CoP21) will take place in Paris. What do you expect from this gathering?
A new framework for international climate action is expected, which would allow it to match the size of the challenge. What has been done up to now is largely insufficient. This framework will hopefully be based on the science reflected in the IPCC reports, and be ambitious and fair for everyone, noting the larger responsibilities of developed countries in past emissions. As the Paris agreement will likely not solve all problems at once, it will be very important that it includes a regular review process, so it can be updated as required.
What role do you see stakeholders like UITP playing in this conference?
UITP can share positive experiences, particularly with developing countries, which must still build large parts of their infrastructure. It is also important that the co-benefits of climate adaptation and mitigation measures in other areas than climate change (improved health, economic development, reduced energy dependence) are highlighted.
Follow Prof. Jean-Pascal Van Ypersele on Twitter: @JPvanYpersele