Vulnerability to climate change

This section describes population vulnerability to health impacts of climate change in Aotearoa New Zealand and explains the role of monitoring vulnerable populations. It provides information on key vulnerable population groups, such as young children (under 5 years), older adults (85+ years), Māori, people living in poverty, and people working in primary industries.

Some population groups will be more affected by climate change than others

People’s vulnerability to climate change is affected by their exposure to changes in the climate, by their sensitivity to the effects of climate change and by their capacity to prepare for, respond to, cope with and adapt to climate changes. Some population groups will therefore have a higher risk to experience health impacts caused by a changing climate [1].

In New Zealand, key vulnerable population groups include:

• Children aged 0-4 years
• Older adults aged 85+ years
• Māori
• People living in poverty (living in lower deciles of the New Zealand Index of Deprivation)
• People working in primary industries

Examples of how these groups could be more vulnerable are:

• people on low incomes generally have fewer resources to be able to protect themselves from exposure to extreme weather
• people on low incomes may be less able to adapt to climate changes because they have fewer resources
• older people are more sensitive to dehydration on very hot days
• Māori communities are often more dependent on climate-sensitive primary industries (like farming and fisheries).

Monitoring vulnerable groups helps to plan for climate change

Population data is useful for environmental health monitoring. We can look at population data alongside environmental data, to consider how much impact climate change might have on a specific population group.

By identifying vulnerable groups in the community, where they are located and how many people there are, authorities can better plan what additional supports might be required for these groups to adapt to climate change. For example, when a heat wave warning is distributed in parts of France, authorities will contact all older people living alone to ensure they are prepared. The aim is to decrease the excess illness and death in older people that has been seen in previous heat waves.

In New Zealand, data on vulnerable populations could be used by local authorities to help decide how to target information and action on preparing for climate changes, including extreme weather events

Some TAs have a high percentage of older people or young children

Overall, New Zealand’s age structure is not dominated by a large number of children aged 0–4 years (6.3%; 294,921 children), or older adults aged 85 years and over (1.8%; 84,351 adults). However, some territorial authorities (TA) have different age profiles compared to the national picture (Figure 1 and Figure 2).

Figure 1: Children aged 0-4 years, by territorial authority, 2018 (percentage of total population)

Figure 2: Older adults aged 85+ years, by territorial authority, 2018 (percentage of total population)

Additionally, our population is getting older, and older adults make up an increasingly large proportion of the New Zealand population.

Large Māori populations in the upper North Island

In 2018, 16.5% of the total population identified as Māori (Figure 3). Māori are likely to be more vulnerable to a changing climate due to increased exposure to environmental risks (eg. many Māori live in the north and east of New Zealand where hot days are projected to increase) [2] and increased sensitivity to its effects (eg. the Māori economy is heavily reliant on climate-sensitive primary industries) [3].

However, these causes of vulnerability need to be balanced against factors that will increase adaptive capacity, like whānau support.

Figure 3: Māori population, by territorial authority, 2018 (percentage of total population)

High levels of socioeconomic deprivation in Northland, East Cape and parts of the Bay of Plenty and Auckland

People who live in poverty are less resilient to environmental risks. For example, on very hot days, it can be hard to get transport to a swimming pool or beach in order to cool down, or to buy and run an electric fan. Similarly, if you cannot afford home and/or contents insurance, a major storm could cause damage that you are unable to repair.

In New Zealand, socioeconomic deprivation is measured at an area level by the New Zealand Index of Deprivation (NZDep) score. Decile 1 is the least deprived 10% of areas, and decile 10 is the most deprived 10% of areas. Regions with high levels of deprivation include Northland, parts of Auckland, parts of the Bay of Plenty, and Gisborne (Figure 4).

For more information on population vulnerability, environmental health, and population statistics, see our Population Vulnerability domain. 

Figure 4: Socioeconomic deprivation index (NZDep2018 decile), by statistical area 2 (SA2)

A high percentage of people are employed in the primary industry sector in the lower South Island

In 2018, 3.8% of the total population in New Zealand (aged 15+ years) was employed in the primary industry sector (Figure 5).

People working in primary industries are more at risk of experiencing climate change health impacts, due to their increased exposure to the outdoor environment. Primary industries (such as farming and fishing) are particularly climate-sensitive industries. A warming climate can put increased pressure on these systems, as well as people and their livelihoods.

People working in primary industries often live in rural areas, and might be difficult to reach in an emergency, or have more difficult access to services such as health care and emergency response. This increases their vulnerability in case of climate extremes such as heat waves, extreme rainfall events or drought.

However, people in rural areas are often more self-reliant, and so are better equipped to cope with emergency situations.

Figure 5: People working in primary industries, by territorial authority, 2018 (percentage of total population aged 15+ years)