The Construction and Property scenarios [NZGBC website] published in 2023, were developed for Te Kaunihera Hanganga Tautaiao – New Zealand Green Building Council (NZGBC).
The scenarios were designed for sector participants to use when conducting scenario analysis.
Scenarios explore three possible futures
- An orderly scenario where global warming is limited to 1.5°C following ambitious and immediate decarbonisation efforts. Under this scenario New Zealand faces moderately severe physical impacts of climate change.
- A disorderly scenario where global warming is limited to 2°C. Delayed policy implementation results in high transition risks from rapid and stringent efforts to decarbonise. Under this scenario New Zealand faces moderately severe physical impacts of climate change.
- A hot house scenario where no additional policies are introduced to curb emissions resulting in global warming of >3°C. New Zealand faces severe physical impacts of climate change under this scenario.
Narratives describe the anticipated climate change impacts under each scenario
They include:
- increases in global temperature
- sea level rise
- number of hot days
- rainfall intensity
- wind speeds
Socioeconomic trends are also explored, including:
- New Zealand population
- aging population
- carbon price
- electricity grid emissions
Anticipated impacts on the construction and property sector are discussed throughout the scenarios. Impacts include energy and carbon limits for new builds, change in building materials used, shift in building use and tenancy type, infrastructure investment decisions, and land use change.
Five main drivers of change for the sector were:
- increasing frequency and severity of extreme weather events
- availability of low carbon materials
- regulatory change
- pressures on centralised infrastructure / aging infrastructure
- carbon price.
The Construction and Property Sector scenarios were developed for the sector to use in climate scenario analysis.
The sector is defined on page 5 of the report Climate scenarios for
the construction and property sector (PDF, 2.7 MB) [NZGBC website]
It includes entities whose primary activity is the development, ownership, or management of buildings, including those providing upstream supporting products and services.
Some public sector entities may find aspects of sector scenarios, such as the Construction and Property scenarios, useful for testing policies or strategies. This will depend on the nature of your organisation and focal question.
In the Climate scenarios for the construction and property sector (PDF, 2.7 MB) [NZGBC website] read more about:
- limitations of the Construction and Property scenarios on page 37
- the meta scenarios and data the Construction and Property scenarios are based on see pages 39-40 and 65
- limitations of the NGFS heat stress and GDP data used in the Construction and Property scenarios on page 72
For more on the limitations of existing global climate scenarios upon which the Construction and Property scenarios are based see this report from the University of Exeter (PDF, 8,2 MB) [Institute and Faculty of Actuaries website]
There are a total of three Construction and Property scenarios, each with a different narrative and emissions trajectory.
Orderly
An ‘Orderly’ 1.5°C scenario where decarbonisation policies are enacted immediately and smoothly (globally, in Aotearoa New Zealand, and within the sector). Whole of life carbon emissions reduction requirements for buildings is at 90% by 2050.
Disorderly
A ‘Disorderly’ scenario where significant decarbonisation is delayed until 2030 (globally, within New Zealand, and within the sector). This leads to global warming being limited to <2°C by 2100. The sector faces high transition risk after 2030 as entities rush to decarbonise.
Hot House
A ‘Hot House World’ scenario where global warming reaches >3°C above pre-industrial levels by 2100. No further decarbonisation policies are enacted (globally, within New Zealand, or within the sector). Emissions continue to rise. The sector faces limited transition risks but extreme physical climate risks, particularly towards the end of the century.