This discussion, held on 18 August 2021, was part of the first stage of ‘Establishing Aotearoa New Zealand’s reference climate scenarios’, a discussion that brought attendees online for two hours during day one of Alert Level 4 lockdown.

The Institute’s initial observations from the 18 August 2021 meeting are as follows:

  • There is a range of interpretations as to what a climate scenario and a reference climate scenario mean in practice. One of the key challenges will be developing a shared understanding of what climate projections and climate scenarios are, how they are different and when they should (and should not) be used.
  • There are a number of different users (audiences) of Aotearoa New Zealand climate scenarios.
  • The time horizon and breadth of climate scenarios (e.g. single or more dimensions) might vary according to the user/audience.
  • There is a risk the public might misconstrue dystopia scenarios as projections.
  • Climate data may not be easily accessible to all interested parties.
  • The reporting regime requires climate scenarios by 2022/23: ​XRB is aiming to issue the first standard by the end of 2022. This would trigger the first reporting period to be for the period commencing 1 Jan 2023, with the first reports then issued 2024.
  • The NIWA 2016 climate scenarios/projections are still considered to be relevant; the next version will not be available for another few years, likely 2023 at the earliest.
  • At present, there is no Aotearoa New Zealand institution that is being required to produce detailed reference climate scenarios (or funded to do so).

Related work

Working Paper 2021/07: Scoping the use of the term ‘climate scenarios’ and other climate-related terms in Aotearoa New Zealand and international literature

The aim of this paper is to:

  • point out the ongoing issue of how climate-related terms are inconsistently defined and used across domestic and international literature;
  • list all such terms and their various definitions; and
  • develop the McGuinness Institute’s climate change glossary.

The Institute has examined domestic and international climate literature, and has found varied uses, definitions and interpretations of climate-related terms and language. Climate-related information must be comparable, and for this reason the language and terminology should be common, clear, concise and easy to understand. This has led to the Institute developing this paper.

The Institute hopes this paper will be useful given the External Reporting Board’s development and issuance of climate standards (NZCS1), as well as the recent announcement of the Emissions Reduction Plan. More generally, the Institute hopes that this paper can act as a foundation for the development of consistent thought and a shared understanding of climate-related terminology.

Discussion Paper 2023/02 – Establishing national climate-related reference scenarios
This discussion paper has been influenced by and adapted from this discussion event. The purpose of this paper is to:

  • explore the benefits, risks and costs of developing a national climate-related reference scenario framework;
  • explore how to create national climate-related reference scenarios; and
  • consider who is best positioned to create national climate-related reference scenarios.

Presentation by Professor Nick Golledge

Professor Nick Golledge (Antarctic Research Centre, Victoria University of Wellington) provides a 15 minute summary of the IPCC Sixth Assessment Report (18 August 2021)

Nick Golledge – IPCC Sixth Assessment Report

Download (PDF, 12.5 MB)

Presentation by Wendy McGuinness

Download (PDF, 6.5 MB)