A report on Pacific population trends to 2050 and a Pacific-led research project on climate mobility – to "stay in place" or to move facing environmental changes – was released on Tuesday.

The report by researchers from the University of Auckland aims to better understand the population dynamics of the region's 13 million people, which are projected to become 20 million by 2050, under the influence of climate change, which has been identified as the single greatest threat facing the Pacific.

The research is looking at where and how climate-related events and environmental changes, such as cyclones, floods, drought, salination of soil and drinking water, heat stress and sea level rise, will impact Pacific people's decisions to "stay in place" or to move, whether within countries, around the region, or beyond, including to New Zealand.

The great majority of Pacific people will still be living and adapting to climate change in their home countries in 2050, the report said.

Actionable research findings with a Pacific lens will assist in addressing the serious challenges of climate mobility, said Professor Yvonne Underhill-Sem, co-lead of the University of Auckland research team with scholars from Papua New Guinea, Solomon Islands, Kiribati, Tuvalu, Cook Islands, Niue and Tokelau.

The research aims to better inform government policy-making, in support of effective, long-term and sustainable change, said Underhill-Sem.

"The insights that have been shared with us show a deep understanding of the challenges faced by communities, as well as careful thought about future options," she said, adding the Pacific research methodologies they use build on shared kinship links and the use of local languages in the 16 community sites where research has taken place.

The research has been commissioned by the New Zealand Ministry of Foreign Affairs and Trade, funded by New Zealand's climate finance.