Experts have been meeting in Brazil to discuss the UN Intergovernmental Panel on Climate Change (IPCC) Special Report on Global Warming of 1.5C.

The meeting, drawing experts from 39 countries, will kick-start a major report assessing the impacts of a global warming of 1.5C on human and natural environments.

Among the lead authors of the report is University of Canterbury's Associate Professor Bronwyn Hayward, whose chapter focuses on sustainable development, poverty eradication and inequality.

In the capacity of a political scientist interested in climate change, she shares her own personal views in this Q&A with Herald science reporter Jamie Morton.
Trying to find ways to keep future warming under the 1.5C mark has been a big task for scientists and officials working under the IPCC umbrella. But is it a realistic prospect?


At the Paris COP21 meeting, Governments agreed to "pursue efforts" to limit warming to 1.5C above pre-industrial levels.

This was a very significant political shift in both ambition and focus.

Achieving this goal will take concerted action, at a far more aggressive rate than anything we have contemplated before.

But it is the task of the special report writers is to evaluate the scientific knowledge for this ambitious target, while also considering how to strengthen our global responses to sustainable development and poverty eradication.

Once we have that information then governments and the public can decide if it's feasible.

Why the focus on this threshold? What does it represent?

From my perspective, numbers don't always mean a great deal for many people, we have heard about a possible 2C warming for so long that I think many people don't realise that a world that is 2C warmer is dangerous, let alone why, how or for whom.

At a global level, an overall increase in 2C can have serious impacts regionally and locally in already dry climates, or in big cities for example.


2C is also associated with extreme events like storms, floods, and drought, sea level, and the loss of the diversity of our ecosystems.

So against this background, the new focus on 1.5C matters hugely, especially for vulnerable communities, like small low lying states who have argued that stabilising the world at 1.5C warmer is crucial to their survival.

1.5C is the level where climate impacts on communities and the environment might be able to be managed safely.

University of Canterbury political scientist Associate Professor Bronwyn Hayward. Photo / Supplied
University of Canterbury political scientist Associate Professor Bronwyn Hayward. Photo / Supplied

It would enable communities to avoid dangerous interference and "tipping points", or far reaching changes that might for example threaten food production and cause serious loss and damage.

You've been over in Brazil at the latest round of IPCC talks around this work. What has this conference involved?

This is more of a working meeting than a conference.

Held about 90km out of Sao Paulo on the Brazilian Air and Space research institute campus, it brought together 86 scientific, technical and socio-economic experts from 39 countries, to start preparing the Special Report on a 1.5C world which must be completed by September 2018.

The week has been very intense intellectually, at times, because you are working with complex problems, across disciplines and it takes time to just get to know everyone.

But it has been such a privileged to work with experts, so focused on trying to provide the best information they can and sharing knowledge as clearly as they can.

We have been meeting in small lead author chapter teams to identify what the key issues are that we have to review, designing an outline of each chapter, and then coming back together to the whole team to talk about plans, and how we will address the issues that affect all parts of the project.

Then there are the basics of determining who is doing what in terms of writing and the draft chapter's content before we all meet again to review the draft.

The reality of the amount of work is just starting to dawn on me to be honest it is quite daunting.

Are there any concerns that, with recent political change, the hard work that culminated in the Paris Agreement could be undone, or that meaningful climate action could take a back-seat?

Here again I am speaking as a political scientist - not for the IPCC.

Of course in political science terms government commitments and community actions will make an enormous difference to the future.

But national governments are not the only actors that are leading significant climate action.

Some global cities now are emerging as the major sites of resource use and leadership in significant efforts to cut carbon, as are some regional states like California which has introduced a set of ground breaking measures that have placed that regional economy on a trajectory to achieving an 80 per cent reduction in greenhouse gas emissions by 2050 - which given the size of California is an impact equal to and better than many countries.

What's the take-home for New Zealanders here: what would an extra 1.5C of warming mean for our environment and society - and what would going past that mean for us?

From my perspective there are two take home messages for New Zealand, in the first instance taking the 1.5C warming seriously means we have to rethink our actions.

In my own view, New Zealand now has have the responsibility and opportunity to contribute to meaningful and deep change in ways that can be sustained by the community, as a globally responsible nation.

We have put a lot of faith and policy emphasis on carbon market solutions but such schemes are unlikely in to contribute to the scale of far-reaching change required by a 1.5C target.

We need to contribute to a global effort in more significant and far reaching ways.

The second message is immediate, New Zealand comprises many low-lying coastal communities and islands including Tokelau, Niue and the Cook Islands and the sustainability of these communities depends on the world achieving a 1.5C target.

In this light, this report is crucial to New Zealand.