According to the Ministry for the Environment, which released these figures, by the end of the century Auckland is projected to have about 40-60 extra days per year when maximum temperatures exceed 25C, and frosts are likely to become rare as hens' teeth.
The city could also lose one to three per cent of its rainfall by 2040, and three to five per cent by 2090. While this may sound balmy, it means by the time my grandchildren are in their 50s, droughts with a severity that Auckland currently only experiences every 20 years will occur every five. This could threaten agricultural production and put pressure on the city's water supply, including hydroelectric power generation. Extreme weather events like the tornado that killed three people and damaged 150 homes in Hobsonville last December, as well as widespread flooding, will become more common.
Then there's Auckland's iconic coastline. Last year the National Institute of Water and Atmospheric Research predicted sea level rises of 0.5m to 1.5m by 2100. Another study by the New Zealand Climate Change Research Institute at Victoria University of Wellington warned that the rate of sea level rise is likely to increase towards the second half of this century, meaning action cannot be delayed.
The Institute even goes so far as to suggest a retreat from sea-front homes and businesses in Mission Bay, Kohimarama and Kawakawa Bay, although it acknowledged that the unpopularity of such an approach means it is unlikely to be pursued. Auckland Council has set a target to achieve a 40 per cent reduction in greenhouse gas emissions by 2040, based on 1990 levels.
According to the Plan: "This will require a transformation from a fossil fuel-dependent, high energy-using, high-waste society to an 'eco - or liveable - city'. This is typified by sustainable resource use, a quality compact form, an eco-economy, and transport and energy systems that are efficient, maximise renewable resources and minimise reliance on fossil-based transport fuels."
The Auckland Energy Resilience and Low Carbon Draft Action Plan, which will be released for consultation and submissions in March 2014, is the Council's primary means of making this happen. It suggests a host of opportunities for lowering the city's greenhouse gas emissions. These include the provision of greater transport choice, as well as reducing our reliance on fossil fuels and the car for transport, a programme that is already underway with the announcement of the $2.86 billion city rail loop.
The Council will also look to reduce energy consumption in Auckland's buildings through its regulations and consenting processes and manage peak demand in electricity through the increasing use of 'smart' meters and electricity control systems. It already provides eco-design advisors offering free, independent advice to designers, builders and home renovators to increase the energy efficiency of buildings.
The Council is also investigating the diversification of Auckland's electricity generation with small-scale wind and solar electricity generation as well as larger projects. This looks promising; a recent study from the University of Auckland suggests that New Zealand is close to the point where the price of electricity supplied by 'distributed generation' could be the same or less than the price of grid-supplied electricity.
Interestingly, this research also suggests that an extensive solar-powered suburbia with electric cars may actually prove more efficient than the more compact city currently being envisaged, where future city expansion will be limited to reduce the need for long urban commutes in cars. This demonstrates how the approach to tackling these issues may need to evolve with changing circumstances and new technologies.
Auckland Council also intends to use its planning powers to try and avoid the potential damage climate change could inflict on the city's infrastructure and population. This will include designing developments to take account of possible sea level rises and managing a retreat from certain low-lying coastal areas if necessary.
The Council is also considering actively promoting self-sufficiency and resilience, as has been previously exemplified by movements like Transition Towns. Mayor Len Brown says: "The focus on carbon emissions is very much front of mind and we can never let that slip. I can't impact what people are doing in Beijing, Zurich or New York, but I can impact what people are doing here in Auckland. It's not about smacking people 'round the ear, it's about leading by example.
"I think buy-in is very good, especially in business. Where business once lagged behind our young people, in terms of sustainable thinking, they are now leading the way."
Wellington
Wellington's City Council's Climate Change Action Plan, regularly updated since it was first created back in 2007, prepares for sea-level rise, storm-surges, flooding, slips, and extreme storms, but also for the difficulty in maintaining water supply in the summer months due to reduced rainfall, higher temperatures and increased demand.
The plan includes a target of reducing the city's greenhouse gas emissions by 30 per cent from 2001 levels by 2020. Already, about a third of Wellington's workforce commutes by public transport, bicycles or on foot, thanks to the city's compact layout and its relatively convenient and comprehensive train and bus system. The city plans to boost this further by spending $12.8 million over the next 10 years on improvements that will make it safer and more enjoyable to walk or cycle. In 2011 it spent $11.4 million to open Manners Mall to buses and create a new shared space for pedestrians, cyclists and cars in lower Cuba Street.
It is also currently spending an additional $9.3 million up until 2019 to expand the city's bus-lane network through the central city and on other key routes from 2012-2019. The city is also looking to the longer-term future of travel, investing in the promotion of electric vehicles, especially for commercial fleet use.
Meanwhile, Wellington is also developing its green belt areas, with about 10 per cent of the city area currently being managed as or reverting back to native bush, and Council staff and volunteers planting about 100,000 trees a year to increase carbon dioxide absorption.
Renewable energy is also a big part of the plan, with the council encouraging projects like Meridian Energy's 62-turbine West Wind farm in Makara. Combined, existing and planned wind farms around Wellington have the capacity to produce 222 megawatts of electricity, sufficient to power 110,000 homes. In future the Council plans to support small-scale power generation with 'feed in tariffs' that set minimum payments for power being sent back into the grid from private solar and wind systems.
It is also investigating ways to incorporate better energy efficiency standards into residential and commercial building regulations in the city. And it partnered with Todd Energy New Zealand to help establish a land ll gas-to-electricity plant that collects methane and runs it through a 1MW generator, producing enough power to supply about 1,000 households.
To adapt to what's coming, the city has commissioned a large amount of research on the potential impacts, including possible sea-level-rise scenarios from 0.5 to 2.5 metres. The authority is using that to inform everything from the design of stormwater drain systems to entire coastal dune landscapes.
Mayor Celia Wade-Brown has said: "Cities, rather than countries, are taking the lead on climate change issues. We need to take a climate change lens to all of Council's activities and programmes. Based on the best available information, as of 2010 the city's emissions had roughly stabilised at 2001 levels. This shows we are on the path to a lower-carbon economy, since both GDP and population have grown, by 29 per cent and 20 per cent respectively. Reaching the 2020 target of a 30 per cent emission reduction below 2001 levels will require a further step change."
Christchurch
Christchurch's traumatic recent history has prepared it more than most for the rigours of risk assessment and disaster planning. The Council is expecting climate change to deliver a 50-80 centimetre rise in sea level, a temperature increase of two degrees and changes in rainfall and extreme weather events. The authority believes the positive side of this could be milder winters and a longer growing season. However, this comes with more intense rain that could increase landslides, as well as ironically, an increased likelihood of droughts during drier periods.
The city is also threatened by new pests and diseases as well as the potential for economic disruption, particularly from rising fossil fuel prices and significant numbers of displaced people from low-lying, drought-prone areas moving into the city.
To try and head that off the city has committed to cutting its greenhouse gas emissions by a fifth by 2020 measured against 2008 levels, and halving them by 2050. This would include shifting more freight onto ships and rail, encouraging public transport, walking and cycling wherever possible and rolling out more public transport of the kind it is currently trialling with a rates-funded hybrid-electric bus. The city intends to cut landfilled waste by two thirds, and is currently investigating the potential of creating algal-based biofuels at its wastewater treatment plant.
Beginning in 2015 the council plans to reduce barriers and increase the affordability and uptake of solar and heat pump hot water heating systems by fast-tracking consents, providing low interest long-term loans and accrediting the systems and installers. There's even $30,000 set aside to encourage people to grow more of their own veggies on private land and suitable public spaces.
A unique part of the picture in Christchurch is Legacy, a partnership created by the council and the New Zealand Green Building Council (NZGBC), with support from Property Council of New Zealand and the Canterbury Employers Chamber of Commerce, and several local development companies.
It has attracted the likes of Westpac, Jasmax, Christchurch International Airport and the University of Canterbury among others: organisations that have pledged to develop and occupy healthy, efficient, and sustainable buildings that create a lasting legacy for the region, and to inspire more businesses to do likewise.
Christchurch Mayor Bob Parker says: "There is an unprecedented opportunity in the rebuild of our city to make the most of latest knowledge and technologies to create a Christchurch fit for the future, one that we can all be proud of."
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