Climate changes will drive freshwater shortages, bring sweeping changes in food production conditions, and increase the number of deaths from floods, storms, heat waves and droughts.
Scientists forecast more rainfall overall, but say the risk of drought in inland areas during hot summers will increase. More flooding is expected from storms and rising sea levels.
Poorer countries, which are least equipped to deal with rapid change, could suffer the most.
Plant and animal extinctions are predicted as habitats change faster than species can adapt, and the health of millions could be threatened by increases in malaria, water-borne disease and malnutrition.
As an increased amount of CO2 is released into the atmosphere, there is increased uptake of CO2 by the oceans, and this leads to them becoming more acidic. This ongoing process of acidification could pose major problems for the world's coral reefs, as the changes in chemistry prevent corals from forming a calcified skeleton, which is essential for their survival.
Global warming will also cause some changes that look likely to create further heating, such as the release of large quantities of the greenhouse gas methane as permafrost (permanently frozen soil found mainly in the Arctic) melts.
Climate Impacts for New Zealand
We cannot afford to ignore what is happening in New Zealand and around the world. It requires a highly coordinated and committed global, national and local response. This will enable us to be adequately prepared to adapt to the short, medium, and long-term impacts of climate change.
New Zealand makes a small contribution to global greenhouse gas emissions, yet has one of the highest per-person rates of emissions for an industrialised country. Most of our emissions come from livestock and road transport.
New Zealand is already experiencing higher land and sea temperatures. The sea rose 14 to 22 centimetres in the last century, the oceans are acidifying, there is more sunshine, and the country’s glaciers have lost a quarter of their ice in the past 40 years.
Some regions have drier soils, altered rainfall patterns, fewer frost days and more warm days. Extreme wind has also increased in some places.
Studies suggest flood and drought events have worsened, and there is a higher likelihood of these happening.
Many of these impacts cannot be reversed.
These effects are expected to intensify in the coming decades and all aspects of life in New Zealand will be affected.
Impacts to Wildlife
Climate change is already affecting wildlife all over the world, but certain species are suffering more than others.
Polar animals, whose icy natural habitat is melting in the warmer temperatures, are particularly at risk. In fact, experts believe that the Arctic sea ice is melting at a shocking rate - 9% per decade! Polar bears need sea ice to be able to hunt, raise their young and as places to rest after long periods of swimming. Certain seal species, like ringed seals make caves in the snow and ice to raise their pups, feed and mate.
Forest dwelling species, such as orangutans, which live in the rainforests of Indonesia, are under threat as their habitat is cut down, and more droughts cause more bushfires.
Climate Impacts for New Zealand Wildlife & Environments
In New Zealand all of our native species and ecosystems will eventually be affected by climate change, either directly or indirectly, but some will be more vulnerable, including:
- Alpine ecosystems are refuges for many of our bird, lizard and invertebrate species, and contain a great diversity of plant species. However, as temperatures rise, increased animal pest pressure (e.g. hedgehogs, rats, wasps) is expected as their range expands to higher grounds. In the long-term, alpine zones will also experience increased woody growth as tree lines and scrub moves upslope, reducing the alpine habitat.
- Freshwater ecosystems will also be particularly vulnerable because they are already subject to high levels of land use pressure (e.g. dams and increased water takes for irrigation). Native freshwater plants and animals will be impacted by climate change directly (e.g. increased flood frequency, lower water levels from drought), and indirectly (e.g. increased water takes/ irrigation and pests and weeds which grow in warmer water).
- Coastal ecosystems (includes estuaries, coastlines, and offshore island habitats) where rising sea levels will ‘squeeze’ our coastal native ecosystems against developed land. Storm surge and increased sedimentation as a result of increasing flood frequency will also affect these ecosystems.
- Vulnerable native species lack the ability to adapt to the impacts of climate changing at the rate expected and may need us to specifically intervene.
- Wildfire and its impact: Not only are habitats such as trees and shrubland burnt, what is left is bare land that, if left, can cause huge issues for erosion, land slumps and sediment, polluting waterways.
Climate Impact on Mental Wellbeing
Climate change will have direct and indirect impacts on psychological wellbeing. After climate related extreme weather events such as storms and fires, common human reactions include stress, anxiety, grief, social tension, feelings of displacement, relationship conflicts, cognitive decline, problems with alcohol and drugs and greater rates of mental health disorders such as post-traumatic stress disorder and depression. Learning and understanding about climate change also affects people even without exposure to a direct event, and may create anxiety, depression, despair, aggression and a host of other emotional upheavals.