Introduction

Tiakina te kura tū te whiwhianuku, te kura tū te whiwhiarangi, kei roku te taiao

Over the past 10,000 years, Aotearoa New Zealand has experienced a largely stable climate. This has supported the development of species and ecosystems that are found nowhere else. This natural environment has formed the basis for where we have chosen to build cities and towns and live our lives. It has framed the development of our economy and influenced how and where we connect with the natural world.

But human activities, both historical and current, are putting pressure on the environment and stretching its capacity to adapt to change. Conditions are changing faster than ecosystems can adapt, making it difficult to restore the environment to a healthy state. Among many things, human activities have driven rapid increases in atmospheric greenhouse gas emissions, causing the Earth to warm. The global mean surface temperature is now 1.1 degrees Celsius above pre-industrial levels. Temperatures are continuing to increase and will likely exceed 1.5 degrees Celsius above pre-industrial levels by early 2030.

This may seem like a small increase in temperature, but these small changes are already having huge impacts. All parts of the Earth’s environment are interconnected, and each additional degree of warming has the capacity to drive increasingly significant changes to the natural environment.

As a result, temperature rise is only the beginning of the story. We are experiencing variations in rainfall patterns, more frequent medium-term droughts, ocean warming to record levels, and glacial ice retreat. Sea levels around parts of Aotearoa have risen twice as fast in the past 60 years as they did in the first half of the 20th century. Extreme weather events are increasing in frequency and severity, causing loss and damage to nature and people.

The biodiversity, or diversity of life, that underpins Aotearoa New Zealand’s unique ecosystems is under threat because of the changing climate. We see this through changes in where species live, their life cycles, population levels and physiology. Climate change also exacerbates the impacts of other threats including invasive species, land-use change, habitat fragmentation, fire risk and pollution. Heat extremes have driven local extinctions of species, and large die-offs on land and in the ocean.

These changes in the environment have consequences for the things we value most: our safety and security, the places we live and play, our livelihoods and economy and our wellbeing. Around 750,000 New Zealanders live near rivers and in coastal areas already exposed to extreme flooding. This includes major urban centres and 500,000 buildings worth more than $145 billion. Sites of cultural significance, taonga (treasured) species, and food security are also at risk in these areas.

The immediate costs from increasing severe weather events driven by warming atmospheric and ocean temperatures are likely to increase. Treasury has estimated the damage from Cyclone Gabrielle and the 2023 Auckland floods may total between $9 billion and $14.5 billion. Increases in extreme weather events, such as drought and extreme rainfall, affect agriculture, horticulture, fisheries, forestry, tourism and the snow sport industry. Food insecurity, loss of livelihoods and uncertainty around climate change have ongoing impacts on mental health. Changing seasons affect mātauranga Māori (Māori knowledge) and many important Māori practices, including the transfer of mātauranga Māori across generations. Climate change and biodiversity loss will make already vulnerable people more so, further reinforce inequalities, with harm falling disproportionately on minorities and indigenous peoples.

A rich biodiversity and resilient ecosystems have the potential to shield us from the worst consequences of climate change. They absorb some greenhouse gases and act as a buffer against extreme weather events and other climate impacts, protecting houses, crops, water supplies and vital infrastructure. Conversely, the continuing loss of biodiversity and degradation of ecosystems will weaken their ability to provide benefits and protection to the extent that we risk reaching points of irreversible change. Human activities are undeniably driving these losses. We are approaching environmental tipping points in many areas, beyond which large and often irreversible changes will be unavoidable.

The impacts we see from climate change will escalate with every increment of global warming – and every bit of warming we can prevent will bring benefits. The magnitude and rate of climate change and associated effects depend strongly on near-term mitigation¹ and adaptation² actions. We face a huge challenge, but we already know many solutions. We can draw strength by embracing the wisdom of our ancestors and holding their legacy close. ‘Kia whakatōmuri te haere whakamua: we walk backwards into the future with our eyes fixed on our past’. By working collaboratively, acknowledging the past and embracing innovative and transformative ways of thinking, we can walk into the future with a greater understanding of how to accept the wero (challenge) that is climate change.

¹ The Intergovernmental Panel on Climate Change (IPCC) defines mitigation as a human intervention to reduce emissions or enhance the sinks of greenhouse gases (IPCC, 2023). ² The IPCC defines adaptation as the process of adjustment to actual or expected climate and its effects in human systems, in order to moderate harm or exploit beneficial opportunities, and the process of adjustment to actual climate and its effects in natural systems; human intervention may facilitate adjustment to expected climate and its effects (IPCC, 2023).

In te ao Māori (Māori worldview), the atmosphere and climate are observed through our connection with and effects on our moana (oceans), awa (rivers), roto (lakes), whenua (land), flora, fauna and people. The concept of hau (wind or breath) acknowledges the journey that the wind makes between different life forms, through the different spheres, connecting our hauora (health) with all the domains of te taiao (the environment) (Salmond, 2014).

When the mauri of the atmosphere and climate is unbalanced, it affects all other systems in te taiao, including people. Mauri is an ao Māori concept that describes the spark of life and active component of that life (Mead, 2003). It is the binding force that holds together the physical and spiritual components of a being or thing (Durie, 1998; Morgan, 2006).

In te ao Māori, many pūrākau (stories) are integral to understanding Māori views of the world, the relationships between people, the universe and atua (Hikuroa, 2017; Marsden, 1988/2003). Atua is a uniquely Māori understanding and personified form of natural realms. Connection to atmosphere and climate extend back to the creation of the world. In one version, Papatūānuku (Earth Mother) and Ranginui (Sky Father) were separated and brought Te Ao Mārama, the world of light. For many Māori, one of their sons, Tāwhirimātea is the atua of weather and the parent of kōhauhau (atmosphere) and āhuarangi (climate). Tāwhirimātea was angered by the separation of his parents and attacked the siblings who caused it with storms, cyclones, droughts and other extreme weather events (Phillips et al, 2016).

Our previous synthesis report, Environment Aotearoa 2022, framed the atmosphere and climate domains with Ururangi and Waipunarangi. Ururangi is the whetū (star) in Te Kāhui o Matariki (the Matariki cluster) that is connected to the winds, and Waipunarangi is the whetū that is connected to rain (see Environment Aotearoa 2022). Te Kāhui o Matariki signals the start of the Māori new year in some parts of Aotearoa and provides predictions for the year ahead. However, in areas such as the Far North, Taranaki, Whanganui, the South Island and the Chatham Islands, the appearance of the star Puanga or Rigel marks the start of the Māori New Year (Lyver et al, 2009).

Observations of the sky have informed specific tikanga Māori (customs and protocols). They are essential for reading the changing of the seasons, through observing the appearance of certain stars and the changing path of the sun and maramataka (Harris et al, 2013). The maramataka provides a framework for understanding te taiao and informing cultural practices (Hikuroa, 2017). Maramataka means ‘the moon turning’ and is the traditional Māori way that time was marked by observing the phases of the moon. It is commonly held that Matariki and the maramataka both inform our understanding of how the various lunar nights affect the world and all its inhabitants. In turn, this understanding informs planning and day to-day activities (Matamua, 2017). Different maramataka across Aotearoa dictate how iwi engage with their local environment, forecasting timings for activities critical to the wellbeing of Māori. Interest is growing in revitalising and recalibrating the maramataka (Warbrick et al, 2023).

Climate change threatens the loss of culturally significant land and taonga species. These species are unquestionably treasured by Māori based on historical, cultural, spiritual and ecological significance. Taonga species vary among whānau, hapū and iwi, which can be due to whakapapa (genealogy) connection, identified kaitiaki (guardian) responsibilities and geographical distribution. Many taonga species have been gathered over generations and are connected to traditional Māori practices, such as mahinga kai and rongoā (healing). They are central to the intergenerational transmission of knowledge, including knowledge on the sustainable use and protection of these taonga species and their associated ecosystems (Awatere et al, 2021; Harmsworth & Awatere, 2013; Smith, 2011). The names of taonga can also vary according to their life-cycle stage, iwi and hapū dialect, and within different regions. Taonga species can also represent symbols of status, association with death, tohu (environmental indicators), predictions of weather, metaphors and stories (Keane-Tuala, 2015).

Our atmosphere and climate 2023 is the latest in a series of environmental reports produced by the Ministry for the Environment and Stats NZ. It is part of the third cycle of reports released under the Environmental Reporting Act 2015 (the Act), following our atmosphere and climate reports in 2017 and 2020.

In 2019 the Parliamentary Commissioner for the Environment (PCE) released a report (PCE, 2019) which identified how the environmental reporting system could be improved and recommended amendments to the Act. Implementation of these changes has started and will provide a stronger foundation to ensure we better understand te taiao and the effects people are having on it.

Our atmosphere and climate 2023 continues the scaled-back format for environmental reports first signalled in Our air 2021. It provides valuable information while we progress the changes needed to improve the reporting system, in line with recommendations from the PCE (PCE, 2019). This is an information-oriented release, with the main focus on updating recent indicators and scientific evidence about our atmosphere and climate.

As required by the Act, we use the concepts of pressure, state and impact to report on the environment, and this forms the basis for the report’s structure. The logic of this framework is that pressures cause changes to the state of the environment, and these changes may affect our values. Aligned with the proposed amendments to the Act put forward by the PCE, this report also includes outlooks as part of the framework. Outlooks are a description of how the environment may change in the future. They are assessed based on current data and trends and likely future impacts on the environment and the things we value.

Due to the interconnected nature of the atmosphere and climate with other environmental systems, this report also documents the effects of climate change on biodiversity and ecosystems. It describes the impact of climate change on our public health, wellbeing, culture, economy, infrastructure and recreation. The evaluation of specific policy is out of scope for environmental reporting releases under the Act.

Mātauranga Māori represents a valuable record of our environment that is unique to Aotearoa and is integral to our reports. Our atmosphere and climate 2023 intentionally elevates te ao Māori, mātauranga Māori and promoting connections across knowledge systems. This included the use of te reo Māori and the continued inclusion of Māori concepts and pūrākau (stories) in our report products.

The data used in this report came from many sources including central and local government and Crown research institutes. Further supporting information was provided using a ‘body of evidence’ approach. This body of evidence includes peer reviewed, published literature, as well as mātauranga Māori and observational tools used to identify changes in our atmosphere and climate environment.

All data used in this report, including references to scientific literature, were corroborated and checked for consistency with the original source. The report was produced by a team of analysts and scientists from within and outside of the Ministry for the Environment and Stats NZ. It was also reviewed by a panel of independent scientists. The indicators related to our atmosphere and climate and the date they were last updated are available on the Stats NZ indicators web pages.