The earth’s atmosphere is made up of oxygen, a large amount of nitrogen and certain other gases, including a small percentage of greenhouse gases.
Greenhouse gases act like a blanket around the earth. When the balance is right, they trap warmth from the sun and make life on earth possible. However, increasing the concentration of greenhouse gases in the atmosphere traps too much heat and causes the climate to change. Increases in concentrations of greenhouse gases, such as carbon dioxide, methane and nitrous oxide, are largely a result of human activities such as burning fossil fuels, deforestation and agriculture.
Although the changes result from natural processes, and we have always experienced periods of extreme weather, the increase in greenhouse gases is generating changes in global, national and local climate at unprecedented rates, resulting in:
- Sea level rise
- Acidification and warming of the oceans
- More heavy rainfall and flooding events
- More frequent and more severe droughts with greater fire risk
- Stronger winds
- More extreme temperatures, more often.
In our daily lives, there are lots of examples of damage caused to people, properties, infrastructure and businesses by extreme weather events (flooding, soil erosion, landslides, droughts), as well as threats to native flora and fauna, and cultural sites of significance, due to changed natural conditions or shortages of water supply.
Climate change refers to the long-term shifts in temperatures and weather patterns we will experience. No one knows for sure just how much the climate will change in the future, but we are already seeing change, and it will have broad effects to our environmental, social, economic and cultural outcomes.
Mitigation and adaptation
Actions in response to climate change generally fall into two categories: mitigation and adaptation. In broad terms, climate change mitigation is about reducing greenhouse gas emissions, and climate change adaptation is about anticipating and adapting to the impacts of climate change.
Mitigation is about taking action to reduce greenhouse gas emissions so that the severity of climate change will be lessened. Examples are the setting of emission reduction targets at the international level to limit average global temperature rise (e.g. Paris Agreement), national level (e.g. New Zealand’s target of net zero carbon emissions by 2050) and local and individual levels (e.g. by measuring and reducing the carbon emissions of organisations and individuals).
Adaptation anticipates and deals with the effects of climate change, helping to build greater resilience by harnessing innovation and responding to impacts such as rising sea levels and coastal hazards or droughts. Most adaptation action takes place at a local and community level (e.g. through land use planning).
Mitigation and adaptation are closely linked: the more we take action to reduce our greenhouse gas emissions, the better the chance that we will have fewer impacts to adapt to in the future. Some actions we can take contribute to both areas, for example, planting coastal vegetation which absorbs carbon (mitigation) and protects properties at the same time by stabilising coastlines (adaptation).
What are the projected effects of climate change?
In 2019 the Bay of Plenty Regional Council (BOPRC) commissioned NIWA to analyse climate change projections and impacts for the Bay of Plenty Region. NIWA's technical report provides up to date information on changes we’re likely to see in our climate over the 21st century.
Read the infographic below (based on a fossil-fuel intensive scenario, RCP 8.5), or watch the short video to learn about the climate change implications projected for Bay of Plenty.
Watch the climate change video