A major new report has outlined the biggest and most pressing risks New Zealand faces from climate change, and they go well beyond the science of changing weather patterns.

What’s all this then?

One of the most dangerous and concerning aspects of climate change is the unpredictability of it all. Some activists even joke about using the term “global weirding”, rather than global warming, because of the way that immense greenhouse gas emissions are expected to break down normal weather patterns. Because of this, we can’t predict the future with perfect accuracy.

With all of this in mind, a new report has been released, with the aim of bringing together all of the potential risks and uncertainties that climate change will bring. It is called the National Climate Change Risk Assessment, and has been developed by the environment ministry.

That sounds pretty dense and heavy.

Befitting the complexity of the topic, the main report weighs in at a hefty 133 pages. The technical report that accompanies it is more like 245.

What is climate change going to do to New Zealand’s weather patterns, on the most simple level?

Fortunately, the report also came with a brochure with pictures, like this one. Incidentally, pretty much all of this stuff is already happening.

Right, now I’m ready for more complexity.

Basically, the report looked at 43 risks, and then assessed them on a scale of urgency (to quote – “measure of the degree to which further action is needed in the next six years to reduce the risk”) and consequences (how nasty things will get if and when they do.) The thing that makes these assessments important is that they are interconnected with each other, and interact with each other in potentially unexpected ways.

What’s an example of this? 

Take this as a potential (hypothetical) scenario of how it could happen, extrapolated out from the various risk assessments. There is an increasing likelihood of droughts in already dry areas, less snowfall on glaciers and mountains, and extreme rain events in which such a volume of water falls that existing systems can’t handle it.

We could end up with a situation in which the first of those two weather patterns combine, to cause a severe drought and irrigation water shortage in Canterbury. Because it is an area with lots of water-thirsty dairy farming, with many farms heavily indebted, a wave of business failures takes place as a result. That then flows in the economy of the towns of the region, where businesses that rely on farm supply sales are based. They start to close too, further hurting the rate paying base for the local councils, who are responsible for maintaining water infrastructure. Then one day, there’s an unexpected deluge that causes severe flooding, totally screwing up the potable water supplies of those towns. What you’re left with is a disaster-hit area which has no drinking water or economic base to rebuild with, and little hope for future economic recovery. The question then becomes, what happens to social cohesion in the aftermath?

This is what is known as a “cascading impact” in the report, in which “a primary threat is followed by a dynamic sequence of secondary hazards.” An example of that is given with this chart showing unadapted stormwater systems.

What are the biggest threats identified? 

The report picked out ten major threats, breaking them down into five domains. These risks are all seen as needing urgent action within the next six years. In turn, they are:

• The natural environment, including coastal ecosystems and indigenous ecosystems. Risks here were seen as having major consequences.
• The human domain, including social cohesion, displacement of communities, and the entrenchment and further opening up of inequalities. These are seen as risks with extreme consequences.
• The economic domain, including costs associated with disaster relief and long term changes, and the risk of instability in the financial sector.
• The built environment, including infrastructure and buildings being vulnerable to sea level rise, and more extreme weather conditions generally – this area is also seen as having an extreme risk profile.
• The governance domain, in which warnings are sounded of “maladaption” (making the wrong choices to meet the challenges) and the risk that climate change impacts across all domains will be exacerbated because current institutional arrangements are not fit for adaptation.

Is there any upside to any of this?

The report did also identify some opportunities from climate change, but they’re pretty sad-sack stuff. For example, the report identified warmer temperatures meaning people would have lower heating bills, and be less likely to die of winter illnesses. Who knows, we might also be able to sell adaptation technology, or grow more bananas or something. On balance though, the potential risks pretty clearly outweigh the level of potential rewards.

Is it too early to talk about adaptation? Shouldn’t we be trying to get global emissions down so these risks become less profound?

Sure, why not. As Dr Judy Lawrence from the Victoria University Climate Research Institute noted, “the assessment was undertaken using two scenarios: a low emissions (RCP 4.5) and a high emissions scenario both at the 50th percentile. This enabled the assumptions around urgency of action to be stress tested for their sensitivity to different plausible futures. There is urgency required under both scenarios.”

Climate change minister James Shaw said that cutting emissions continued to be a goal for the government. “However, the climate is already changing and there will be some effects that we cannot avoid. So, in addition to driving the transition to a zero carbon New Zealand, this Government is also working to ensure our communities are made much more resilient to the unavoidable effects of global climate change,” he added.

Will this help? 

Dr Lawrence suggested it was another step towards “the implementation of coherent adaptation across New Zealand.” And NIWA’s chief climate scientist Dr Andrew Tait said “the key risks identified in the report clearly show where we need to focus our climate change impacts and adaptation scientific research over the coming years to reduce our nation’s vulnerability and enhance adaptive capacity”.

So what happens with the report now?

It will be fed into the great beast of bureaucracy, and within two years the government will be required to respond with a National Adaptation Plan. Work on that is already underway, which is nice given the urgency of it all.