The National Climate Change Risk Assessment. A case of science denial.

Ian Harrison, Tailrisk Economics

A Tailrisk Economics review of the National Climate Change Risk Assessment (NCCRA) found that it grossly overstated climate change risks and that the assessments were based on poor quality evidence and analysis.

The purpose of the NCCRA, which was released in August 2020, was to provide the ‘best available evidence, information and assessment of risks’ to inform the development of a National Adaptation Plan (NAP) that will set out what will be done to respond to climate change risks.

The central message was that the climate change risks are very serious, even in the relatively near term. Eight of the 43 sectoral risk assessments found that the consequences of climate change would be ‘extreme’ by 2050.

The Tailrisk Economics review of the NCCRA’s social, political and economic risk assessments, assigned evidence quality scores of between 0 and 10 to the cited evidence and provided a summary of every accessible reference, giving the reader the capacity to form their own view of the quality of the NCCRA assessments.

The average evidence quality score was a very low 3.09. Often the assessments consisted of little more than a recitation of the ‘five horsemen of the apocalypse’ : more extreme weather events, more drought, more river flooding, higher sea levels, and more wildfires, followed by unsubstantiated claims that they will have either major or extreme consequences, with little regard to the underlying science.

Much of cited evidence was irrelevant or did not support the arguments. Critical research reports that did not support a ‘catastrophist’ narrative were often ignored or misrepresented, and in some cases steps were taken to cover up ‘inconvenient’ evidence. For, example, NIWA recently did a flooding risk study that showed flooding risk would actually fall as the climate got warmer. But in its press release NIWA claimed that this work had not been done, and the NCCRA ignored this important result.

Some of the NCCRA assessments were plainly absurd. it was claimed, for example, that extreme risks to social cohesion by 2050 would result in ‘permanent disruption to education, employment and community services. Patterns of daily activity and behaviour unable to continue. Coping range of all communities exceeded.’ All because the temperature had increased by less than one degree; sea levels had risen by less than 20 centimetres and there had been a very limited increase, if any, in ‘extreme’ climate events.

Only two of the supporting references related to New Zealand, and neither raised issues about widespread social disruption. The evidence base was not even suggestive of the nationwide impacts implied by the extreme risk assessment.

Contrary to the picture painted in the assessment the science does not show that the New Zealand climate will deteriorate markedly over this century. Wind speeds will not increase significantly, and river flooding risk might actually fall overall. Droughts are likely to become somewhat more frequent in already drought prone areas, and there might be a few more wildfires. But these effects are likely to be outweighed by the positive impacts of climate change, including warmer weather and more fine days in summer, and the impact of carbon fertilisation on primary sector productivity. Sea level rise is a real issue but the impacts in the NCCRA were overstated by using the wrong methodology to assess storm surge flood risk.

The conclusion that climate change will have, at most, only a moderate impact on advanced economies (particularly if they have a temperate climate) is well established in the international literature. The 5th Intergovernmental Panel on Climate Change came to the following view:

For most economic sectors, the impact of climate change will be small relative to the impacts of other drivers (medium evidence, high agreement). Changes in population, age, income, technology, relative prices, lifestyle, regulation, governance, and many other aspects of socioeconomic development will have an impact on the supply and demand of economic goods and services that is large relative to the impact of climate change.

Well-functioning markets provide an additional mechanism for adaptation and thus tend to reduce negative impacts and increase positive ones for any specific sector or country (medium evidence, high agreement).

Why then do we see such a different picture in the NCCRA?

• Some analysts and institutions might believe that it is necessary to exaggerate to buttress support for New Zealand’s net zero target.

• So many people and institutions in the climate change industry have been repeating the mantra of markedly increased risks from floods, sea level rise, wildfires and stronger winds, that it is now regarded as an immutable truth.

• Consultants and academics are following the money. A balanced or skeptical perspective could put their funding at risk.

• Unethical and/or imcompetent behaviour is unlikely to have negative consequences. As most of the ‘experts’ are in on the game they can circle the wagons to protect the narrative, isolating any dissent.

To read the full paper go here

Ian Harrison (B.C.A. Hons. V.U.W., Master of Public Policy SAIS Johns Hopkins) has worked with the Reserve Bank of New Zealand, the World Bank, the International Monetary Fund and the Bank for International Settlements.