The debate is over: man-made climate change is real. If you’re not convinced by the 97 per cent of active climate scientists who say so, then take a step outside. According to Nasa, last year was the hottest our planet has experienced since records began in 1880, and from farmers to firefighters, everyone is noticing the difference.
So if climate change is happening after all, should we just give up the ‘fight’ and enjoy the long summers? Sadly it doesn’t work like that. If we don’t take action, the world will just keep get hotter. Instead of a fight to stop climate change, we’re now in a fight to stop the worst.
That also means we need to get real about dealing with the effects that are already locked in – regardless of what we do. So how will climate change affect us? We asked dozens of experts how our warmer planet is likely to touch our lives – our families, our houses and our jobs – in the near future.
As conditions warm, home gardeners will be able to grow fruit and vegetables they can’t at present. Think bananas and mangoes in Auckland, kiwifruit and feijoas in Christchurch, and lemons in Dunedin. However stone-fruit trees, which benefit from frosts, will bear less and poorer quality fruit as frost-days diminish. Gardeners will also have to contend with more varied and abundant pests and plant diseases. Warmer temperatures mean that insect pests (such as the Queensland fruit fly) will thrive.
When you think of the ‘greenhouse effect’, it’s easy to imagine this will benefit food crops, in the same way that a greenhouse is great for boosting yields. However at the global level increasingly erratic weather, and explosions in plant diseases and pests, are actually set to make food harder to grow.
Within 15 years, it’s likely that average global crop yields will be falling. Longer term, each extra decade of climate change is expected to shrink global average yields by 1 per cent, when food production needs to be rising 14 per cent per decade to keep pace with population growth (we’ll have a projected billion more mouths to feed in 15 years’ time).
All of this means that food prices are likely to rise, with more frequent price spikes. Growing zones will also shift. Bananas, chocolate (cacao), coffee, tea, wheat, corn, cherries
and walnuts are just some of the foods that may be disrupted.
In regions where climate change raises UV radiation, the very taste of food crops such as wheat may change via alterations in the plants’ chemistry.
Best case – We’ll survive and adapt, thanks to scientists such as Perth-based Kiwi Janet Bornman, who is investigating how to make food crops hardier and more nutritious in the more challenging conditions ahead.
Worst case – Most crop projections have assumed a 2°C rise; the few that factored in a 4°C+ rise predict yield declines of 20 per cent or more. If this happens widespread shortages and famines would likely follow.
Your home and property
Your home at risk
An increase in extreme weather events is already taking a toll on Kiwi homes. Insurance payouts due to severe weather were unusually high in the last two years: $175 million in 2013 (making it one of the three most expensive years since records started in 1968), and $145 million last year (in the top 5 or 6 most expensive).
As climate change effects take greater hold we will need to brace ourselves for more property damage from flooding, sewage and storm water overflow, landslides or windblown debris, depending on where we live.
The insurance industry here is already taking climate change seriously and lobbying for better access to climate-risk info for home builders. However it seems inevitable that premiums and excesses will go up as the risks increase.
Eventually policies and prices may be based on a hazard risk profile for each individual property. In some areas, such as Otago, you can already search on the council website for hazard risks by address.
Ultimately, expect more homes to become un-insurable (already, in flood-prone parts of Australia an average-value house can cost as much as $25,000 to insure for flood damage alone).
In 2013 a storm brought the sea into properties along Auckland’s upmarket Tamaki Drive. In 30 years’ time, such major coastal floods will occur in Auckland every ten years, according to NIWA projections. Flood damage will become more common elsewhere. In some places, such as the lower North Island, land is also subsiding due to tectonic movements, making the problem worse.
Shorelines naturally move back and forth over the years due to cycles in sea level unrelated to climate change (10-30m along Auckland’s east coast, the Coromandel and Bay of Plenty, for example). These cycles will likely mask additional erosion associated with climate change-driven sea level rise over the next two to four decades. After then, we could see shorelines moving much further inland during erosion phases in many (particularly east coast) areas. Within the next century, most beaches on the coastlines mentioned above are expected to move further inland by at least 20-30m, assuming
a 1m sea level rise.
The cost of keeping the sea at bay will, for some coastal properties, become too much. In some places unlucky beachfront property owners will eventually have three options: build an expensive seawall (typically $4000 per metre); move your home ($10,000+); or give it to the waves.
Expect heated community meetings and litigation as residents and councils wrestle over complex questions. For example will ratepayers who live back from the beach agree to fund seawalls that benefit beachfront homes the most?
Bylaw changes may already affect you
Most councils use a projected sea level rise of 1m by 2115 to calculate safe distances to build from the shoreline, called ‘setbacks’. Already, in some regions, what that means is if you want to build an extension on your beachfront property and the existing building is on the wrong side of a setback, you have to shift the whole building landward. Likewise, if you want to rebuild, you’ll need to locate the new building behind the setback.
You’d expect that today’s sky-high coastal property values will eventually fall. How quickly is impossible to say – however it may not be wise to mortgage yourself to the hilt to buy that dream beach pad, in case falling prices see you owing more than you own.
Best case – Smart engineers are thinking of ways to deal with climate change effects – for example, by building rowing clubhouses on floating platforms, or beach houses on skids so they can be moved by tractor. Meanwhile, the better that councils plan for the future, the less likely it is ratepayers will have to fork out for weather-damaged public infrastructure.
Worst case – If emissions aren’t sufficiently curbed, NIWA predicts that coastal flooding of Auckland will become a yearly event before the century’s end. If the highest projections for sea level rise come to pass (unlikely, but still possible), within the century whole coastal communities will be faced with two options: armour the shoreline with seawalls; or move some buildings and infrastructure landward, and dismantle the rest to make way for the sea.