Fires, floods and storm surges have caused many Tasman District residents to be evacuated from their homes in recent years. Key transportation networks continue to be impacted, with the highway over the Takaka Hill still under repair after ex-Cyclone Gita. Freshwater is becoming a scarce resource, as evidenced during the 2019 drought.
Climate change is likely to bring warmer temperatures, more extreme weather patterns and rising sea levels - all of which will have widespread environmental, social, economic and cultural impacts. Issues such as drought, water security and flooding are expected to become more severe, and existing challenges around coastal erosion may be exacerbated. Industries such as agriculture and horticulture may need to adapt to remain profitable in the new climate. Local Government New Zealand estimates that councils in New Zealand are facing an estimated cost of $5-8 billion to replace vital infrastructure lost to climate change over the next half century.
Challenges also bring opportunities. Investment in changes for horticulture, services, management and technology will be required and may drive innovation from our region.
The sea level is rising around the District and will have some impact on the present coastline and coastal communities.
As water warms it expands. Even if the glaciers and icesheets stay stable there will still be a certain amount of sea level rise. However we are expecting that with increasing global temperatures there will be further glacial and icesheet retreat in the future. For those glaciers and icesheets on land, the melt will lead to a sea level change.
Historic sea level rise in New Zealand has averaged 1.78mm per year, with the Port Nelson tide gauge recording a slightly lower rate than the national relative average of 1.57mm per year (MfE, 2017). Measured sea levels at Port Nelson have risen approximately 150mm since the early 1940s.
The rate and magnitude of future sea level rise is uncertain, especially later this century and beyond. Scientists advise that sea levels will continue to rise and that levels are likely to rise at an accelerated rate over time as the earth’s temperature rises, meaning changes could happen sooner than predicted – or there may be changes to emission rates that reduce the rate of warming.
Uncertainty is a key message. What we do know is that rising sea levels will have increasing implications for development and infrastructure in coastal areas along with environmental, cultural and societal effects.
Ex-tropical cyclone Fehi was a significant coastal storm inundation event that effected our district on 1 February 2018. The large storm surge which coincided with a high spring tide and large waves damaged the coastline and flooded roads, reserves and nearby properties and houses. Sea level rise will increase the exposure of our coastal land to these type of events, creating new hazards in areas that have not previously been exposed.
We're starting a community discussion around climate change and sea level rise. We need everyone to join in.
In 2015, NIWA released a climate change and variability report for Tasman District Council. The report describes changes which may occur over the coming century in the climate of the Tasman region, and outlines some of the possible impacts of these changes.
Download a copy of the report:
The key points from this report are:
By 2090, the Nelson-Tasman region could expect*:
|Spring|| 0.6°C to 2.6°C temperature rise
1% less to 1% more rainfall
|Summer||0.6°C to 3.2°C temperature rise
No change to 10% more rainfall
|Autumn||0.7°C to 3.2°C temperature rise
3% to 7% more rainfall
|Winter||0.7°C to 3.1°C temperature rise
4% to 11% more rainfall
* Projected changes are relative to 1995 levels. The values provided capture the range across all emissions scenarios. They are based on scenario estimates and should not be taken as definitive. For more information, see the full report.
On Wednesday 3 August 2011, Tasman District Council hosted two leading New Zealand specialists to explain the nature of climate change, its impacts in New Zealanders' health, properties, infrastructure, environment and rural industries.
Dr Jim Salinger, Auckland Climate Scientist, and Rod Oram, Business Journalist, spoke to a crowd of over 130 on "Maintaining farm productivity and profits in an uncertain climate".
Please follow these two links below to view the presentation: