Regional report on impacts of climate change to inform risk assessment and planning

A regional evaluation of the impacts of climate change commissioned by Waikato Regional Council will be shared with territorial authority, iwi partners and business to inform regional and sub-regional climate risk assessments and planning.

Yesterday, the Climate Action Committee discussed CLIMsystems’s report, Climate Change Effects on Waikato Region, looking at middle of the road and extreme climate futures based on the most recent international climate modelling data (CMIP6) and several scenarios from the 6th Assessment Report from the International Panel on Climate Change (IPCC).

Council’s science manager, Dr Mike Scarsbrook, told the committee the impacts of climate change would be different across the region.

Dr Scarsbrook said while the results showed the variations in temperature changes across the region were predicted to be quite small, it was quite a different picture regarding rainfall, with extreme rainfall and drought events predicted for parts of the Waikato.

Model predictions indicate increasing air temperatures across the region, with middle of the road projections indicating around an additional 1.0 °C by 2050 and 1.5 °C by 2090 compared to the current state.

And while there is little evidence of significant changes in annual mean rainfall at the regional scale, extreme rainfall and drought intensity is likely to increase.

The probability of drought for a middle of the road climate scenario would increase from a current situation of around 25 per cent probability (1 year in 4) to around 33 per cent (1 year in 3) by 2050 and almost 37 per cent by 2090.

The report will be used to inform a climate change risk assessment for the region, which the committee endorsed yesterday. The assessment will look at risks to our economy, the social and cultural fabric of society and our natural and built environments. A key area of focus will be the risks inherent in any change in strategies, policies or investments as society transitions to a low-carbon economy.

Climate Action Committee chair Jennifer Nickel says the up-to-date projections of climate change effects support future regional planning.

“We want to share modelling results with our territorial authority and iwi partners, as well as other key strategic stakeholders to help them plan for the effects of climate change.

“We’ll also be looking to them for risk information they may have already published for our risk assessment for the Waikato.

“We want a wide range of people to be involved in this assessment – we need to understand the risks to all our people. We have been working with district councils on the development of their coastal adaptation plans but I really like that we have the opportunity to lead this piece of work and we’ll be looking at all risk domains, not just the coastal risks.”