6. Vulnerability assessment, climate change impacts, and adaptation measures
Introduction and overview
A low population density and related long-distance infrastructure, long coastline and varied geomorphology, and an economy reliant on the primary production sector make New Zealand vulnerable to climate hazards. Research and dissemination of findings on the impacts of climate change, vulnerability and adaptation options remain a high priority for New Zealand. In addition the development and dissemination of methodologies for stakeholder-led impacts assessments, and implementing adaptation measures to these impacts, have been a major focus of work over the past four years.
Since the Third National Communication there have been several Government-led reviews of climate change impacts and vulnerability on a national or sector-specific basis which have incorporated impacts assessment and adaptation methodologies. In May 2004, the Ministry for the Environment coordinated and published a national review, Climate Change Effects and Impacts Assessment, updating the climate change scenarios used in a previous impacts report in 2001. This document serves as a guidance manual for local government and includes extensive guidance and information on impacts assessments.
Much of New Zealand's urban development has occurred in areas vulnerable to the actions of the sea and in recent years, as coastline development has intensified, the potential impacts of coastal hazards has increased. A second major manual, Coastal Hazards and Climate Change, focuses particularly on coastal issues and provides guidance to local government on impacts and adaptation methodologies for this area.
Other reports have addressed issues of changes in the risk of flooding and drought.
There are also a range of reports from ongoing research programmes carried out by publicly-owned and private research institutes. The studies are aimed at gaining a better understanding of projected climate changes and their impact on sector-specific production methods, infrastructure, and native ecosystems. Research in this area includes:
- increasing understanding of New Zealand's past and present climate and its variability
- downscaling global climate model results to account for the New Zealand topography in future climate projections, and developing scenarios for rainfall and temperature changes
- increasing understanding of the responses of a range of plant and animal species to elevated temperature and carbon dioxide concentrations and changes in rainfall
- developing and refining crop models based on experimental work
- changing distribution of native and introduced plant species to changing climatic conditions
- developing soils models to increase understanding of the turnover of soil carbon.
More information on research on the impacts of climate change is included in Chapter 8 in this Fourth National Communication. A range of regional assessments of vulnerabilities, impacts and adaptation options have also been carried out, often initiated by or in response to requests from local government.
New Zealand has a highly variable climate. Current year-to-year variability is of the same order of magnitude as the projected mean changes to the 2030s, so it is seen as important to consider both anthropogenic and natural variability in developing adaptation strategies.
Scenarios of climate change
For New Zealand, the assessment of climate change impacts is scenario-based. The scenario approach is necessary because of the uncertainty of future greenhouse gas emission levels, differences between modelling results from different global climate models, and uncertainties arising from the downscaling of global model results to the local New Zealand scale.
The most recent downscaled scenarios were developed by the National Institute of Water and Atmospheric Research (NIWA) under contract to the Ministry for the Environment, and are published in Climate Change Effects and Impacts Assessment (Ministry for the Environment, 2004). These scenarios are based on transient model simulations by several international groups.
These new scenarios differ from those used in earlier national impacts assessments in that they use the full IPCC scenario range (that is, covering an increase of between 1.4 to 5.8°C in globally-averaged temperature by 2100 compared with 1990). As with the earlier assessments, they do not assume any policy interventions specifically aimed at constraining anthropogenic greenhouse gas emissions. The downscaling has also been extended to include further variables, to provide estimates of "potential evapotranspiration deficit" for use in the studies of drought risk described below.
The downscaled rainfall projections from the majority (but not all) of the global model simulations suggest an increase of the average westerly flow across New Zealand through the coming century, with increased rainfall in western areas and decreases in the east. All of the models suggest that for the coming century the increase in New Zealand-averaged temperature will be less than the increase of globally-averaged temperature, due to the thermal inertia of the Southern Ocean.
Uncertainty of the downscaled model results is still high due to differences in patterns downscaled from different global climate models, particularly in the area of regional rainfall projections. 4NC Table 29 gives the range of projected temperature change, and 4NC Table 30 gives projected rainfall change, for different geographical regions in New Zealand for the 2030s (2020 to 2049) and 2080s (2070 to 2099).
4NC Table 29: Projected changes for each regional council area in seasonal and annual average temperature (in °C)
4NC Table 30: Projected changes for selected rainfall stations within each regional council area in seasonal and annual precipitation
Current research in the area of climate scenarios includes the development of a regional climate modelling facility at the National Institute for Water and Atmospheric Research. The modelling is based around the United Kingdom Meteorological Office Unified Model. Control runs have been satisfactory and the National Institute for Water and Atmospheric Research is planning to run future scenarios during the 2005/2006 year.
Expected key impacts of climate change
In May 2004, the Ministry for the Environment coordinated and published a national review, Climate Change Effects and Impacts Assessment, updating the scenarios used in the previous impacts report published in 2001. The new report uses the updated climate change scenarios that cover the full IPCC scenario range as well as incorporating additional research carried out over the three years since the last Government-led impacts assessment.
The report provides current projections of the expected overall changes in physical variables and emphasises how these compare with present climate extremes and variations. The broad expected pattern of change is:
- increased temperatures (with greater increases in the winter season, and in the north of New Zealand)
- decreased frost risk but increased risk of very high temperatures
- stronger west-east rainfall gradient (wetter in the west and drier in the east)
- increased frequency of extreme (heavy) daily rainfalls
- increased sea level
- increased westerly winds.
The main features of climate change scenarios identified in this report largely agree with those of the earlier impacts report. However some findings relating to changes in extremes are now on a firmer basis, and some general climate change projections have been updated for a wider range of emission scenarios.
The Climate Change Effects and Impacts Assessment report is particularly directed at identifying and quantifying potential effects on local government functions and services, and outlining methods for assessing the likely magnitude and relevance of such effects. It shows that the mid-range projected human-induced changes that might be expected over the next 30 years are of similar magnitude as current natural variations of the climate about the long-term mean (such as the El Niño-Southern Oscillation or the Interdecadal Pacific Oscillation). This means that over the next 30 years, natural climate patterns could either offset, or exacerbate, the trend due to anthropogenic climate change.
Changes in the severity and frequency of climatic extremes (that is, droughts and heavy rain) will continue to provide the major risk of short-term impacts on key sectors such as agriculture and urban infrastructure and the magnitude and frequency of these climate-related weather extremes is likely to change. For example what currently is an unusually warm year could be the norm in about 30 years, while an unusually warm year in 30 years' time is very likely to be warmer than anything experienced at present.
The report provides guidance on how information on the magnitude of climate change effects can be applied to assess the risk associated with various impacts, and on incorporating climate risk assessment into local government regulatory, assessment and planning processes. A summary version of the manual, Preparing for Climate Change: A Guide for Local Government, has been published and has been distributed widely.
Coastal hazards
Much of New Zealand's urban development has occurred in areas vulnerable to the actions of the sea and in recent years, as coastline development has intensified, the potential impacts of coastal hazards has increased. The Ministry for the Environment has coordinated and published a manual, Coastal Hazards and Climate Change (Ministry for the Environment, May 2004), focusing on coastal issues and providing guidance to local government. The manual provides a risk-based decision-making framework and recommends that, as a minimum, figures for sea level rise of 0.2 metres by 2050 and 0.5 metres by 2100 are used when considering sea-level rise in projects or plans.
Drought risk
Water is a critical resource for New Zealand and drought risk is expected to increase during this century in all areas that are currently already drought-prone. A report commissioned by the Ministry for the Environment and the Ministry of Agriculture and Forestry, Changes in Drought Risk with Climate Change (Ministry for the Environment, 2005) gives local government and the agriculture sector an indication of how big the drought changes could be in the various agricultural regions of New Zealand. The report estimates "potential evapotranspiration deficit" from future time series of daily rainfall, obtained by adjusting observed daily rainfalls by factors obtained from the downscaled climate model predictions. Key findings include:
- Under a "low-medium" scenario, by the 2080s severe droughts (defined in the report as the current one-in-twenty year drought) are projected to occur at least twice as often as currently in a number of areas in eastern New Zealand.
- Under a "medium-high" scenario, by the 2080s severe droughts are projected to occur at least twice as often in much of eastern New Zealand and more than four times as often in a number of areas.
- In some dry areas, a drought of what is currently regarded as of medium severity could become the norm by the 2080s.
- The projected increase in the accumulated potential evapotranspiration deficit would probably produce an expansion of droughts into the spring and autumn months. For a "medium-high" scenario, the drying of pasture in spring is advanced by about a month in the 2080s in dry eastern regions, relative to the present climate.
Additional studies carried out by the National Institute for Water and Atmospheric Research and the economic consultancy Infometrics show that climate variations can have significant economic impacts on the production from dairy output (Tait et al., 2005). This is further confirmed by economic modelling carried out by the Treasury (Treasury, 2002), which indicated that droughts are one of the leading causes for yearly fluctuations in New Zealand's GDP, in addition to currency fluctuations and import and export price shocks.
A related study by the National Institute for Water and Atmospheric Research commissioned by the New Zealand Fire Service indicates that the increasing dryness of the landscape is likely to increase the fire risk in many parts of New Zealand, with potential consequences for the managed and natural ecosystems, housing and infrastructure (New Zealand Fire Service, 2005).
Flood risk
Climate change is expected to bring an increase in heavy rainfalls as well as an increase in drought. The increased frequency of extreme heavy rainfalls is expected to lead to an increased risk of flooding in some areas, and this has been the subject of several reports. The Ministry for the Environment is leading a two-year work programme to improve how New Zealand manages its flood risk and river control. One of the factors included in the work is consideration of the changing flood risk in a time of climate change.
Economic impacts
While the preceding reports have been concerned primarily with the physical impacts of climate change, the potential economic vulnerability for flooding has also been studied. A report, The Waikato Weather Bomb: Understanding the Impact, (Ministry for the Environment, 2004) has been produced for the Ministry of the Environment by the New Zealand Institute for Economic Research, the Institute of Geological and Nuclear Sciences, the National Institute for Water and Atmospheric Research and the University of Tasmania. The report looked at the economic costs and community understanding and responses to flood risk for the Coromandel area following the 21 June 2002 "weather bomb" that caused major flooding to a number of townships in the area. It addressed the need to both understand the economic effects of extreme events and to understand the way in which communities understand, perceive and prepare for such risks.
Energy sector impacts
The Ministry of Economic Development's energy supply and demand model SADEM has been run on a number of climate scenarios relating to global climate change and expected extreme events. Using data from the National Institute for Water and Atmospheric Research and additional modelling from Infometrics, analysis on the effect of climate change on the wider economy is being assessed.
Initial studies indicate that climate change in general should be beneficial to New Zealand in an energy production and demand sense. Stronger westerly winds and warmer ocean conditions are expected to result in greater rainfall in the upper catchment areas of New Zealand's southern hydroelectricity generation lakes. These lakes are responsible for 40 to 50 percent of New Zealand's electricity generation. The stronger winds in general are also expected to supplement wind power generation. New Zealand currently has some of the best wind sites in the world with an average utilisation factor in the order of 45 percent (compared to a European average of 25 percent). Whilst wind provides only two to three percent of current generation, this is expected to increase to more than 10 percent by 2020. On the demand side, higher temperatures should ameliorate heating demand. Whilst cooling demand is also likely to increase, the energy demand ratio is overwhelmingly in favour of the former in New Zealand's predominantly temperate environment, although there will be significant regional differences in the resulting changes in summer cooling and winter heating demand.
These initial studies have not included the effects of natural long-term climate variability. Wratt (2003) suggests that a change in the phase of the Interdecadal Pacific Oscillation relative to that over 1978-1998 might mean the anticipated increased rainfall in the southern upper catchment areas would not eventuate over the next 20 to 30 years. There may also be competition for water resources with irrigation in increasingly dry eastern areas.
Health
Potential negative impacts on human health from climate change have been identified in the spread of vector-borne diseases, heat waves, and pollution of water supplies in rural areas. Positive health effects are expected from warmer winters and related reduction in cold-related illnesses.
Health risks from the introduction of disease vectors are being addressed as part of New Zealand's biosecurity mechanisms, including the Biosecurity Science Strategy. Other potential health impacts from climate change are generally incorporated into ongoing public health policies as they typically do not represent new threats, but rather a possible exacerbation of existing problems, such as clean water supply and direct impacts of heat waves, or a likely reduction in winter illnesses. However, with the exception of the introduction of disease vectors, other pressures on the public health system in many instances appear to outweigh the need for climate change-specific adaptation measures in the New Zealand context.
The modelling of the potential future suitability and distribution of vector-borne diseases is facilitated by the HotSpots integrated assessment system (refer "Regional and sectoral tools and impact studies" in Chapter 6 for more details).
Agriculture
Agriculture is likely to experience benefits from extended growing seasons in the south and from carbon fertilisation, as well as negative impacts from droughts, floods and erosion, invasion of subtropical species, and warmer winters leading to increased spread of some pests and diseases. The balance between benefits and costs is not yet clear but will depend on regions, frequency of extreme events compared to average changes, and the extent of adaptation to changes.
In addition to the general impact studies and those on drought and flood risk, mentioned above, a number of research programmes provide specific information on impacts and adaptation in the area of agriculture. These include investigating the response of various pasture and arable species to changes in temperature, carbon dioxide concentration and rainfall, and the adaptive breeding of new cultivars (for example, kiwifruit with reduced winter chill requirements, drought resistant pastures and high-quality subtropical pastures).
Recent research on climate change effects on pastoral ecosystems has shown that long-term biogeochemical feedbacks reduce the fertilisation effect of elevated carbon dioxide. Pasture soils under elevated carbon dioxide appear less able to supply plants with nitrogen and phosphate leading to a syndrome known as "progressive nutrient limitation"; this syndrome has been observed in a wide range of ecosystems internationally as well as in New Zealand. There are significant implications of progressive nutrient limitation for agriculture - including changes in fertiliser requirements - and in natural ecosystems because of the strong link between nutrient supply and biodiversity. This phenomenon is being studied in the New Zealand Free Air Carbon Dioxide Enrichment (FACE) experiment.
Improved ecosystem models have become available in the past four years offering the possibility of more accurate predictions of pasture responses to elevated carbon dioxide and temperature, more relevant regional projections and a better tool for testing adaptation options.
Potential impacts and adaptation measures in the eastern agricultural regions of New Zealand have been explored in a series of community workshops. The publication that resulted, View from the Ground (Earthwise Consulting, 2003), offered a farmer's perspective on climate change and adaptation. Largely positive and proactive because of the perceived capacity of farmers to adapt, the report has led to further workshops and the production of a resource kit (Earthwise Consulting, 2005) for the farming communities in these areas. Among the adaptation measures required are management of irrigation schemes and water supply systems and changing land use in response to changing erosion and drought risk. The potential for soil erosion in these areas is expected to increase if there is an increase in drought frequency and severity coupled with episodes of heavier rainfall.
Biodiversity
Some native ecosystems may be put under additional pressure from climate change, with little ability of migration to adapt to changes because of the fragmented landscape. Areas at risk include dry lowland forests, some specific species with a limited climatic envelope, several freshwater species requiring cold conditions, and flow-on effects in predator/prey relationships following climate extremes. Knowledge about the impacts of climate change on New Zealand native ecosystems is currently limited. Most at risk is the native bird fauna threatened by the recent advance of avian malaria.
Emerging infectious diseases are an increasing threat to natural biodiversity, due to human movement, habitat destruction and climate change. Increasing vector distributions are of particular concern. Over the past three decades, the mosquito vector of avian malaria in Hawaii (where the disease has wiped out half the native bird species) has been spreading south through New Zealand. This raises the possibility that, as climate change and land use continue to alter mosquito distributions, much of New Zealand's native avifauna may be at risk. In conducting the first survey for avian malaria in New Zealand for more than 50 years, Landcare Research has demonstrated that avian malaria is now present and that such a fate is a likely possibility, indicating that pre-emptive management against disease may be necessary.
Fisheries, aquaculture and marine ecosystems
Increasing water temperatures and associated changes in oceanic and atmospheric circulation are likely to present a number of challenges for New Zealand's marine industries. The surface of the ocean surrounding New Zealand has warmed by near 1°C over the past century. For many fish species, a one degree change can be very significant, either in terms of affecting juvenile survival, modifying predator-prey relationships, or changing preferred spawning and/or feeding regions.
For one of the most valuable fisheries, hoki, relatively low recent recruitment in the western stock has shown some correlation with climate. As a consequence of a decline in stock biomass, the hoki catch quota has been reduced from 250,000 to 100,000 tonnes in the past four years. Although other factors may have contributed to the decline, it is possible that recruitment to the stock is, or has become, more sensitive to climatic variation, and that recent conditions have been detrimental to recruitment. In a similar way to hoki, the recruitment of red cod has also been relatively high during colder conditions, which are associated with the El Niño event. Conversely, for snapper, relatively high recruitment and faster growth rate have been correlated with warmer conditions. A similar pattern of recruitment has been found for gemfish. For the former two species, climatic indices have been incorporated into the calculation of short- or medium-term predicted yields. El Niño appeared to be associated with the invasion of the Chilean jack mackerel into New Zealand waters in the mid-1980s, and this species now dominates the jack mackerel fishery in some areas.
Climate changes are likely to be significant also for local aquaculture. In the Marlborough Sounds, changes in wind circulation and associated rainfall patterns modify coastal river flows, and lead to changes in the stratification of the water column in the vicinity of mussel farms, influencing the nutrient supply. Such changes have been observed in relation to the El Niño/La Niña cycle, and the expected increase in drought risk in eastern regions of New Zealand is likely to have a long-term influence on the character of coastal waters in the Sounds and elsewhere.
Māori
Māori have a disproportionate economic interest in land and forestry assets. In considering the output from agriculture alone, Māori output is estimated to be approximately $700 million dollars representing about 7.4 % of New Zealand's total agricultural output (New Zealand Institute of Economic Research, 2003), against a land resource base of approximately 5 percent of land in New Zealand.
Some areas of land owned by Māori are prone to erosion. However, there is targeted Government assistance such as the East Coast Forestry project that promotes commercial forestry to control soil erosion in the region. In the year 2000 there were 25,854 hectares of plantings. To 2005 plantings increased up to 30,000 hectares.
Māori also place high cultural value on land, including areas that could be impacted by events like flooding or ocean surge due to climate change. Statutory and cultural imperatives on land ownership more particularly for Māori, may make relocation in response to climate change more difficult. In addition prioritisation in terms of adaptation, as well as cost, could hinder implementation of adaptation measures. This can contribute to the risk of reduced economic output from Māori land compared to other New Zealand land, and also from other assets.
In response to climate change the Government has consulted with Māori since climate change became a significant issue and continues to work with this area with Māori.
Regional and sectoral tools and impact studies
An integrated impact assessment tool developed in New Zealand is the CLIMPACTS model system and its derivatives. These models incorporate the patterns of regional climate change, such as those developed by the National Institute of Water and Atmospheric Research, and scale them relative to modelled, time-dependent global temperature changes (for example, from IPCC), in order to create scenarios that are used directly for impact assessments. Theclimate change scenario generator is integrally linked with sectoral impact models (for example, crop models, hydrological models). The main advantage of this system is that it provides a high degree of flexibility in terms of the scenarios and impacts that can be evaluated. It is readily updated to reflect the latest findings of the IPCC and allows comprehensive evaluation of environmental sensitivities for selected sectors.
The CLIMPACTS programme has developed a range of different application scales for national, regional and site-specific impacts and adaptation assessments. The main scales are: national (0.05º latitude/longitude grid; monthly climate normals); regional council (0.01º latitude/longitude grid; time series of monthly and daily climate data); site-specific (time series of monthly and daily climate data).
A variation of the CLIMPACTS model has been developed to predict changes in suitable habitats of several mosquito species capable of transmitting diseases such as Ross River virus and dengue fever - the HotSpots model (developed jointly by the International Global Change Institute and the Wellington School of Medicine, with funding from the New Zealand Health Research Council). The model includes spatial climate and land-cover data, the typical entrance points of these diseases' vectors through shipping ports and airports, and social transmission conditions such as population density. Combined, these factors allow not only projection of changing suitability of habitats, but also estimations of changes in the establishment of risk vectors and eventual disease outbreak under current social and health care conditions.
The CLIMPACTS programme, with Foundation for Research, Science and Technology funding and with additional support from international agencies such as the United Nations Environment Program Global Environment Facility and the Asian Development Bank, has recently developed methods and tools for assessing the "human dimensions" of climate change. These developments include the capacity to generate scenarios of land use changes, to examine adaptation options and to evaluate benefits and costs. Part of the effort has been to create a flexible "open framework" model system (SimCLIM) that can be customised by end-users. These tools are part of a larger methodology, called CCAIRR (Climate Change Adaptation through Integrated Risk Reduction) which promotes the "mainstreaming" of adaptation into decision-making. These integrated methods and tools, developed and applied initially in New Zealand, have also been applied in, for example, Australia, Sri Lanka and various Pacific Island countries.
Details on the CLIMPACTS model and its applications are available on the internet at www.waikato.ac.nz/igci/climpacts.
Regional assessments
Under New Zealand's devolved system of resource and environmental management, concrete actions to address and minimise impacts of climate change are to a large extent the responsibility of local government. This responsibility has seen a number of authorities commission reports identifying the possible climate change hazards specific to their regions. These have included Environment Bay of Plenty (Griffiths et al., 2003); Environment Canterbury (Tait et al., 2005a); Horizons Manawatu Regional Council (Tait et al., 2005b) and Wellington Regional Council (Tait et al., 2002). The Ministry for the Environment has also studied a number of location-specific case studies to demonstrate impacts assessment methodologies and location-specific decision problems. These case studies include stormwater design for existing and greenfield developments, an economic assessment of the implications of sea-level rise for the management of housing stock, and an analysis of the barriers and solutions in decision-making by local government.
A new product developed by the National Institute for Water and Atmospheric Research offers geographic layers of both current values and future scenarios of selected climate parameters (for example, temperature, rainfall, potential evapotranspiration deficit). Councils can use these along with layers they already hold in their Geographic Information Systems (for example, topography, soils, infrastructure) to explore possible impacts of various future scenarios, and also to explore possible suitability of other land uses under a changed future climate.
Private-sector assessments
Natural hazards represent a major insurance field. Some parts of the insurance industry in New Zealand are active in modelling future risk in a changed climate (Insurance Australia Group, 2004, 2005).
Aside from the insurance industry the private sector has focused predominantly on managing the impacts of climate variability and adapting to well-known natural patterns of climate change within shorter time horizons. Most of this work occurs in the agriculture sector with regard to the management of droughts and through seasonal climate forecasts, and the building sector including through assessments undertaken by the Building Research Association of New Zealand (Building Research Association of New Zealand, 2004). The land transport agency, Transit New Zealand, has also developed a preliminary position and undertaken some scoping work on the relevance of climate change impacts on the roading network and the possible adaptation options in high risk areas.
Adaptation policy
Under the New Zealand approach to the management of natural resources and the risks from natural hazards, most concrete actions to address and minimise effects of climate change fall under the authority of local government (city, district and regional councils). Planning to reduce the adverse effects of natural hazards is particularly important at local government level because of the local effects the hazards or resources usually have, which may require locally distinct management and adaptation methods.
A focus of recent work has been the development of guidance to assist local government agencies manage the effects of climate change. The New Zealand approach to adaptation policy consists of a hierarchical set of legislation, guidance material on impacts assessment and the scoping of adaptation options, case studies, and underpinning information material. This set of adaptation policy measures is outlined below.
Legislative background
In New Zealand, legislation establishes the responsibilities of local authorities for avoiding, minimising, and mitigating the costs and effects of natural hazards and managing natural resources:
- Local government is responsible for the avoidance and mitigation of natural hazards through plans and rules prepared under the Resource Management Act 1991. Under the Act, councils must protect the life-supporting capacity of air, water, soils and ecosystems; generally by regulating the effects of human development on the environment. The councils and their communities decide how to protect the environment using rules in district and regional plans, which are legally binding documents.
- Local government has responsibility under the Civil Defence Emergency Management Act 2002 for "civil defence". The Act seeks to improve New Zealand's resilience to emergencies through promoting a comprehensive, all hazards approach to managing risk.
- Under the Local Government Act 2002, local government has a responsibility for providing services and utilities necessary for "community well-being" while taking a sustainable development approach and a long-term focus. Community well-being includes four dimensions: environmental, social, economic and cultural.
Strengthening of the legislative mandate to address climate change effects
The large uncertainties in local projections of the impacts of climate change make it difficult to mandate or implement specific actions at a national scale aimed at adaptation to climate change. To provide greater legal certainty about the responsibilities by local government to consider the effects of climate change, the Resource Management Act was changed in March 2004 to require all persons exercising duties and functions under the Act to have particular regard to the effects of climate change (s. 7(i) Resource Management Act). This legislation change has removed earlier ambiguities in interpreting the scope of the Act by local government and other stakeholders engaged in managing natural resources and hazards at the local level.
Guidance and information materials
Support for local government to meet the provisions of this legislation has included the guidance manuals referred to earlier (Climate Change Effects and Impacts Assessment, Ministry for the Environment, 2004; Coastal Hazards and Climate Change, Ministry for the Environment, 2003), the summary guide Preparing for Climate Change: A Guide for Local Government and an introductory brochure, primarily for elected officers (Local Communities: Planning for Climate Change, Ministry for the Environment, 2004). The legislative and planning context is further outlined in a best practice guidance note (www.qp.org.nz/plan-topics/climate-change.php) providing information on how to assess the significance of, and respond where necessary to, the effects of climate change within the local government planning and decision-making system.
The guidance manuals contain detailed quantitative information on the likely biophysical changes in climate for different regions of New Zealand, including information on the likely changes in extreme events. In addition, they provide the legislative context for decision-making, and outline a methodology for assessing climate change impacts in a way that facilitates adaptation within standard decision-making processes.
A particular focus of this guidance is to outline to councils how to integrate the assessment of climate change impacts into their existing risk assessment, policy-making and decision-making processes. The guidance material recommends a staged approach to climate change assessment in planning. It starts with a qualitative assessment of potential risks for functions and services provided by councils, followed by a preliminary quantitative ("screening") analysis of the likely impacts of climate change for specific issues. If the simple screening analysis shows a potentially significant impact from climate change on natural resources or hazards, the methodology then recommends a more detailed analysis using complex and location-specific models and scenarios.
In addition to the generic assessment methodology outline in the guidance material, several case studies supported by the Ministry for the Environment (see URS NZ, 2004; Harris Consulting, 2003; Opus International, 2003; and Lawrence Cross and Chapman, 2003) give practical examples give practical examples of the methodologies used to incorporate provision for climate change into urban stormwater design, floodplain management, flood risk management, and coastal hazards. These may be downloaded from http://www.climatechange.govt.nz/resources/local-govt/guidance.html
The guidance material advises that for nearly all resources and natural hazards, the mean changes associated with climate change over the next 30 years are generally expected to be comparable with the extremes from existing natural climate variability. Hence they are of a type and magnitude already known to local government and can be planned for and managed using current systems simply by mainstreaming a climate change component into current local government planning and management practice. The extremes in a changed climate will likely lie outside the current range and may require new adaptation measures. However the congruence between expected mean changes and current extremes makes it easier for councils to incorporate climate change in their activities, building on current known vulnerabilities to climate variability and extremes. It also means that adaptation can be seen as a "no regrets" policy, because it leads to a reduction in vulnerability to existing hazards as well as making communities more resilient against future pressures arising from climate change.
Other adaptation measures
Notwithstanding the responsibilities of local government, it is recognised as important that policy makers at national level, and decision makers within industry groups, take account of the possible effects of climate change in formulating policy and developing strategic plans.
MetService, the state-owned enterprise responsible for weather forecasting in New Zealand, is under contract to the Government to provide storm warnings and warnings of high rainfall events to the New Zealand public, as well as maintain its routine weather forecasting duties. Further, the National Institute of Water and Atmospheric Research produces monthly climate forecasts with a time horizon of three months. These forecasts are primarily intended for the farming community but can also be of use to local government in managing water supplies.
Adaptation in the international context
New Zealand recognises that adaptation plays a significant role internationally, and has supported a range of measures to share information and best practice with other countries. New Zealand believes that despite differences in national circumstances, a range of important lessons regarding effective implementation and enabling policy frameworks can be learnt and shared between different countries.
In October 2004, New Zealand hosted an international workshop on adaptation in developed countries, in partnership with Australia, to share information about the status and focus of current adaptation programmes, and to discuss key issues, barriers and solutions for topics and sectors of relevance. A summary report of the workshop has been made available (www.climatechange.govt.nz/about/international-workshop/index.html).
New Zealand also actively engages in sharing of information and funding of adaptation activities in developing countries, particularly in the Pacific. Actions include the provision of seasonal climate forecasts, in-country capacity building and enhancement of climate monitoring and data analysis, and support for specific adaptation projects through its overseas development aid programme. The CLIMPACTS integrated assessment tool has been used widely as a training and capacity building tool in a range of countries.
At the multilateral level, New Zealand officials also participate in a range of fora that aim to gain a better understanding of the role of adaptation in future climate change commitments, and options to assess the effectiveness of adaptation measures and support for adaptation. Relevant activities where New Zealand continues to actively participate include the pre- and in-session workshops by the Subsidiary Bodies for Scientific and Technological Advice; the Annex I Experts Group and Global Forum for Sustainable Development of the OECD; and the Centre for Clean Air Policy's "Future Actions Dialogue".
Future research and implementation issues
The comprehensive analysis by the National Science Strategy Committee for Climate Change of gaps in vulnerability and adaptation, conducted in 2001, remains largely valid. Particular current priorities in the climate change area are:
- improved climate modelling, particularly of water resources and extreme events including floods and droughts, at a range of scales
- economic assessments of the costs associated with climate change impacts and adaptation and residual costs
- dissemination of existing knowledge to end-users and stakeholders across central and local government and the private sector to support mainstreaming of adaptation into sector-specific assessment and decision-making processes.
While for some sectors the primary effort is likely to lie in the dissemination of existing knowledge to support decision-making by stakeholders, in other sectors additional knowledge would be available. These sectors include:
- marine ecosystem and fisheries
- terrestrial natural ecosystems and biodiversity
- the effects of climate change on the indigenous Māori population and their traditional resource management approaches.
New Zealand has not at this stage developed an assessment of critical limits or tolerable windows with regard to climate change impacts and coping capacity.
Another important area for future work is the merging of top-down and bottom-up approaches to impacts assessment and adaptation. Most assessments have used top-down approaches based on model projections, but an increasing body of work in the agriculture sector has used bottom-up assessments. Future work may address the merging of such bottom-up approaches with model-based and economic assessment studies.
