Skip to main navigationSkip to main content
The University of Southampton
We're launching a new website soon and would love your feedback. See the new design
Public Policy|Southampton

Generating world-class evidence for climate change policy

Sally at Stockholm University with other IPCC lead authors
Sally at Stockholm University with other IPCC lead authors

Over the last three years, climate change science has been really exciting as it has been a rare opportunity to develop science that has directly fed into world-leading climate policy. I have achieved this through my work on sea-level rise, together with other Southampton scientists including Dr Phil Goodwin, Professor Robert Nicholls and Dr Ivan Haigh.

Generating new science

In 2015, the climate change community came together in climate negotiations in Paris to agree on ‘holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels’. I was fortunate enough to go to Paris with students to meet the Maldivian government to discuss the impacts of sea-level rise just before the negotiations started, and together with many others in the climate change community I did not feel that such an ambitious target was coming.

The lack of foresight from the scientific community in achieving such a target meant the need for new science. Unlike past papers where we had projected rises in sea-level for high emissions scenarios, we now had to focus our efforts on projecting impacts for low emissions scenarios, focusing around the 1.5°C and 2.0°C targets.

Having won three rounds of funding from NERC/ Department for Business, Energy and Industrial Strategy (BEIS), BEIS and the Collaborative Adaptation Research Initiative in Africa and Asia (supported by UK Department for international Development and the Canadian International Development Research Centre), we set about defining:

* emission levels and other climate parameters,

* how much sea-levels could rise,

* what the impacts could be globally,

* and for vulnerable areas, such as cities, small islands and deltas.

Reporting the evidence

The evidence from all of our papers was reported in the Special Report on the implications of global warming above 1.5°C from the Intergovernmental Panel on Climate Change (IPCC), an international body for assessing the science related to climate change. I was fortunate to be one of 91 lead authors world-wide in this report. The chapter that I worked on assessed the impacts of warming on human and natural systems. I led on the impacts of sea-level rise, which covered implications globally, for cities, deltas, estuaries, wetlands, small islands and adaptation. I found our Southampton work extremely valuable, as other peer reviewed literature on impacts at 1.5°C, rather than climate change impact in general, was really challenging to find.

An IPCC report is an extremely thorough scientific document requiring three rounds of drafting. Each draft is sent out for peer review by scientists and governments around the world who can comment on each draft. Altogether, we had 42,001 reviewer comments to respond to. Not surprisingly this took a long time! The comments on my section were very useful, and it helped broaden my knowledge and understanding, and therefore improve the content of the report. What I found amazing was the thoroughness of the review process at every stage. For instance, one sentence I wrote in the Summary for Policy Makers was checked very thoroughly by my co-authors four times, in terms of scientific confidence and robustness. I had to repeatedly recheck my facts and their context, which included revisiting the findings in some of the papers which I wrote, as they were two of the only three journal papers world-wide which dealt with that particular issue. Our results also fed into the headline statements from the report.

Discussing results with policy experts

During the project and before the report was published we presented our findings to scientists and policy experts who deal with the UK government’s climate policy at BEIS. This included a briefing note and a presentation. Later, our work was included in a POST note – an independent, balanced and accessible briefing on public policy issues. Discussing the scientific needs and results with those who deal with climate policy was really interesting and useful, as I was able to learn exactly what they needed for the negotiations. For instance, one aspect they were particularly interested in was the differences in impacts between a world where temperatures rise 2.0°C compared with 1.5°C.

One of our funders, NERC also helped to facilitate the meeting, and we discussed how best to disseminate our work to raise awareness with the media.

Bruce Currie-Alder (Program Leader, Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA), International Development Research Centre who funded one of the projects commented, “This science on the implications of 1.5°C and 2.0°C is transformational. It gives the international community a new level of detail of regarding the magnitude of different impacts, over practical time scale ranging from 2030 and beyond. These findings are helping to enhance the realism to country commitments ahead of the 2023 stocktake, and already informing IDRC’s own investments in climate-resilient development.”

Report release

The IPCC special report on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty was released on 8th October 2018. Having generated the science, written the report, it was amazing the see the science and media response. We released a local press release and I was interviewed on radio and television, with results from our papers being cited in BBC online news. We also presented our Southampton findings related to the report in a packed seminar room that evening at the University, which was presented in project blogs. I presented my findings at Stockholm University the following week, and have since presented my research to Fulbright Scholars when they visited the University in January 2019.

Overall, generating new science for global policy makers and a particular policy response has been extremely exciting, particularly where our scientific evidence has had a direct impact and will really make a difference in generating evidence to illustrate the adverse effects of climate change.



Brown, S., Nicholls, R.J., Lazar, A.N., Hornby, D.D., Hill, C., Hazra, S., Appeaning Addo, K., Haque, A., Caesar, J. and Tompkins, E.L. (2018) What are the implications of sea-level rise for a 1.5°C, 2°C and 3°C rise in global mean temperatures in the Ganges-Brahmaputra-Meghna and other vulnerable deltas? Regional Environmental Change 18(6), 1829-1842. DOI: 10.1007/s10113-018-1311-0

Brown, S., Nicholls, R., Goodwin, P., Haigh, I., Lincke, D., Vafeidis, A., & Hinkel, J. (2018). Quantifying land and people exposed to sea-level rise with no mitigation and 1.5 and 2.0 °C rise in global temperatures to year 2300. Earth’s Future. DOI: 10.1002/2017EF000738

Goodwin, P., Brown, S., Haigh, I., Nicholls, R., & Matter, J. (2018). Adjusting mitigation pathways to stabilize climate at 1.5 and 2.0 °C rise in global temperatures to year 2300. Earth’s Future, 1-24. DOI: 10.1002/2017EF000732

Goodwin, P., Haigh, I., Rohling, E., & Slangen, A. (2017). A new approach to projecting 21st century sea-level changes and extremes. Earth’s Future, 5(2), 240-253. DOI: 10.1002/2016EF000508

Nicholls, R., Brown, S., Goodwin, P., Wahl, T., Lowe, J., Solan, M., Godbold, J., Haigh, I., Lincke, D., Hinkel, J, Wolff, C. and Merkens, J.-L. (2018) Stabilization of global temperature at 1.5°C and 2.0°C: Implications for coastal areas. Philosophical Transactions of The Royal Society A, 376 (2119). (doi:10.1098/rsta.2016.0448).

Policy brief:

Warren, R., Andrews, O., Brown, S., Forstenhaeusler, N., Gernaat, D., Goodwin, P., Harris, I., He, H., Hope, C., Gonzalez-Colon, F., Nicholls, R., Osborn, T., Price, J., van Vuuren, D. and Wright, R. (2018) Risks associated with global warming of 1.5°C or 2°C. Tyndall Centre for Climate Change Research. Briefing note to BEIS.


Privacy Settings