23 April 2026
26-OIAD-00774
Warwick Schaffer
[FYI request #34220 email] Tēnā koe Warwick
Thank you for your email of 24 March 2026 to the Ministry for the Environment (the Ministry)
requesting the following under the Official Information Act 1982 (the Act):
“Does MFe recommend counsels use RPC 8.5 (ssp5 8.5) to modeling sea level rise
when mapping high-risk hazard zones?
If not, which scenario would be more appropriate.”
The National Adaptation Plan (NAP) recommends that a middle of the road scenario (SSP2-
4.5), and a fossil fuel intensive development scenario (SSP5-8.5) is used for detailed hazard
and risk assessments in both coastal and non-coastal environments out to 2130. This
recommended use is alongside a range of emissions scenarios including the more moderate
SSP1-2.6. A copy of the NAP can be found on the Ministry’s website, here:
https://environment.govt.nz/publications/aotearoa-new-zealands-first-national-adaptation-
plan/ The Ministry’s Coastal Hazards and Climate Change Guidance recommends using relative
sea level rise (RSLR) to account for land uplift or subsidence to improve local estimates of
when climate change induced coastal inundation might occur. A copy of this guidance is
available on the Ministry’s website, here:
https://environment.govt.nz/publications/coastal-
hazards-and-climate-change-guidance/. The NZSeaRise method provides estimates of RSLR
around the entire coastline under a range of plausible future climate change scenarios. You
can access these estimates here:
https://searise.nz/resources/nz-searise-projections/. Using high-end climate scenarios, such as SSP5-8.5, to inform stress testing and risk
assessments enables planners and developers to identify when, and to what extent, areas
could be affected by climate change as a ‘least regrets’ approach. Stress testing for SSP5-8.5
does not mean designing for SSP5-8.5, instead it estimates inherent risk before actions are
taken to manage and decide what level of risk is tolerable.
You have the right to seek an investigation and review by the Office of the Ombudsman of my
decision relating to this request, in accordance with section 28(3) of the Act. The relevant
details can be found at:
www.ombudsman.parliament.nz.
PO Box 10362, Wellington 6143 | Freephone 0800 499 700 | environment.govt.nz
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Please note that due to the public interest in our work, the Ministry publishes responses to
requests for official information shortly after the response has been sent on our website at:
https://environment.govt.nz/about-us/official-information-act-requests/. If you have any
queries about this, please feel free to contact our Ministerial Services team at:
[email address]. Nāku noa, nā
Lauren Long
General Manager – Science, Evidence and Reporting
Ministry for the Environment | Manatū Mō Te Taiao
PO Box 10362, Wellington 6143 | Freephone 0800 499 700 | environment.govt.nz
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