Managing climate change
Managing climate change
For immediate release: 5 June 2008
Environment Bay of Plenty can plan better for future climate change thanks to a new report from the Ministry of the Environment.
The report called Climate Change Effects and Impacts Assessment: A guidance manual for local government in New Zealand, aims to help local government identify opportunities and risks caused by climate change.
Environment Bay of Plenty chairman John Cronin welcomed the report.
“Climate change will have a significant impact on our lives and our agriculture here in the Bay of Plenty. It is therefore really valuable to see better information emerging that we can use to work with our communities to plan and manage climate change in our region,” said Mr Cronin.
The new climate change predictions released by National Institute of Water and Atmospheric Research (NIWA) this week confirm that climate change will have an impact on the Bay of Plenty.
The region’s average annual temperature is predicted to increase by more than 2°C while the average annual rainfall will fall by two per cent.
Projected rainfall for spring in the Bay of Plenty is projected to fall by five per cent by 2040, while autumn rainfall is projected to increase by three per cent. This could lead to more frequent floods and droughts.
The information in the two reports will be used
• plan for flood hazards including river control and coastal management;
• calculate drainage and stormwater calculations;
• manage land and surface water; and
• manage biodiversity, for example, pest control.
Mr Cronin said Environment Bay of Plenty already had a team of staff planning for climate change and resources were available for residents.
The issues Environment Bay of Plenty is discussing include:
supporting the Coast Care and estuary care programmes;
• adapting land use practices to cope with climate change;
• supporting pest plant and animal management; and
• enhance the resilience of ecosystems by improving water quality and natural habitat and reducing the stress caused by invasive species.
Environment Bay of Plenty has supported preliminary work for an ongoing project by the kiwifruit industry, which is looking at the risks and opportunities sparked by climate change As part of the project growers, pack houses and suppliers were interviewed to gauge their knowledge and views on the impact of climate change.
“We are glad to be supporting an industry which is so essential to our economy here in the Bay of Plenty,” said Mr Cronin.
A down-to-earth working guide is available for Bay of Plenty farmers and communities to help them adapt to climate change – and survive whatever the future brings. It uses real-life case studies to highlight ways farmers can alter farm practices to better cope with changes in the climate.
The resource kit, called “Adapting to Climate Change in Eastern New Zealand – a farmer perspective” was funded by the Sustainable Farming Fund and various agencies, including Environment Bay of Plenty.
You can read copies in public libraries, at district and city councils, and at Environment Bay of Plenty offices. The resource kit is also available online at http://www.earthlimited.org/resources.html.
For more information on climate change in the Bay of
What does climate change mean for the Bay of Plenty?
A snapshot of the 2030s
It is virtually certain that the climate will be warmer, especially in winter. For the Bay of Plenty, winters will be on average warmer by 0.8 °C compared with the period 1970 – 2000, with fewer cold days. Other seasons will be about 0.7 °C warmer. This means that the average temperature in coastal Bay of Plenty will be similar to conditions in Kaitaia today.
In general, the change varies with seasons and geography. There will be drier springs and summers and slightly wetter winters. Coastal areas are likely to be drier.
Projected seasonal rainfall changes range from -7.5% to +7.9%, depending on location and season.
• The Rotorua Lakes could expect 4.5% (90 mm) more rain in winter.
• The Manawahe area could experience 7.5% (135 mm) less rain in spring.
snaphot of the 2080s
In the 2080s, winters will be warmer by more than 2.3 °C compared to the period 1970 to 2000, while other seasons will be warmer by 1.8 °C.
The Rotorua, Rotoehu, Rotoma and Okataina areas should be prepared for 8% (160 mm) more rain in winter in the 2080s. Some parts of the coastal area (such as Katikati, Te Puke, Maketu and Waihau Bay) will experience drier springs with spring rainfall reduced by as much as 18% (250 mm).
What are we preparing for?
Extreme rainfall events:
While there is a large variability in extreme rainfall frequency in this region, various modelling studies suggest that heavy rainfall events will occur more frequently in New Zealand over the coming century. It is possible that long-term trends in extreme rainfall will not be noticeable in the Bay of Plenty region until the latter half of the 21st century. Over the next 50 years, changes are more likely to be caused by natural climatic variability than greenhouse gases.
Droughts that currently occur about once every 20 years could happen once every 5 to 10 years. There will be drier average conditions, particularly in coastal areas and in spring. The projections are for a decrease in spring rainfall and an increase in winter rainfall. Rainfall changes are more uncertain than temperature changes.
An increase in severe wind risk may occur, but there is insufficient information for quantitative predictions. Over the next 70 to 100 years, ex-tropical cyclones might be slightly less likely to reach NZ, but if they do, their impact might be greater than now.
In the next 50 years, the mean westerly wind component across New Zealand is expected to increase by 10% of its current value. Increasing westerlies are one reason for a drying trend in the Bay of Plenty. Strong winds are expected to be more frequent with the warmer climate together with an increase in the frequency and intensity of low-pressure systems.
Sea level is estimated to rise by 37–55 cm over the next 70 to 100 years. To plan for the coastal environment, we’ve adopted a projected increase of 49 cm by 2100.
What are the predicted changes and their impacts?
• Inundation of low-lying coastal areas
• Accelerated and more extensive coastal erosion
• Increased drainage costs, which may become unsustainable in some low-lying places
• Salt-water intrusion into freshwater sources
More frequent and intense rainfall
• Increased flood risk
• Increased erosion risk and landslides
• Increased threats to infrastructure
Drier average conditions, particularly
in coastal areas and in spring, more dry days (especially in
• Water security problems could lead to irrigated agriculture in some places becoming vulnerable
• Drier average conditions and higher temperatures will lead to increased drought risk
temperatures, less cold days (particularly in winter)
• A longer growing season
• Increased biosecurity threats throughout the region
• Long-term impacts on primary industry, such as spread of sub-tropical pasture species and insufficient chilling for Hayward kiwifruit
• Reduced frequency of frost inland and at higher elevations
• Less cold-stress is likely to reduce lamb mortality
Climate trends in recent decades may already be affecting the health of New Zealanders, but any such effects are difficult to demonstrate unequivocally because it is often difficult to separate the effect of changes in climate from the effects of changes in other social and environmental conditions. The impact of climate change depends on the extent and rate of warming, and on how well individuals and society can adapt. A study commissioned by the Ministry for the Environment shows that climate change can affect human health both directly (temperature extremes and heavy rainfall) and indirectly (water supply, pollen causing allergy, ozone depletion, infectious diseases carried by animals or insects, and stress).
Changes in climate are likely to influence primary industries as production is often influenced by climate conditions. The Bay of Plenty’s primary production (agriculture, forestry and fishing industry) covers 45% of the land and involves over 10% of its labour force. On the other hand, there may be economic opportunities through the introduction of new commercial crops that is more suitable for the coming climate.