How might climate change affect my region? Climate change in Nelson and Marlborough
Nelson and Marlborough is New Zealand's sunniest region with warm, dry and settled weather during summer, and mild winters.
A change in our climate as a result of global warming and other influences means we need to think about how we are going to plan for and manage the projected impacts of climate change in Nelson, Marlborough and New Zealand. But we also need to take appropriate action to reduce our share of greenhouse gas emissions responsible for global warming and climate change impacts.
Some of the predicted impacts of a moderate rate of climate change for Nelson and Marlborough include changes in average temperature, sea level rise and rainfall patterns. In general, most of the region will be warmer and wetter.
Climate scientists estimate that temperatures in Nelson and Marlborough could be up to 2.5°C warmer over the next 70-100 years. This compares to a temperature increase in New Zealand during last century of about 0.7°C. To put this in perspective, the 1997/98 summer, which many New Zealanders remember as particularly long, hot and dry, was only about 0.9°C above New Zealand's average for the 1990s.
Most of the region could be up to 10% wetter while coastal Marlborough could be up to 10% drier. The region as a whole is likely to experience more varied rainfall patterns and flooding could become up to four times as frequent by 2070.
The effects of climate change may bring significant costs to the community.
If extreme weather events become more frequent or severe, the costs and damages associated with them are also likely to increase. The cost of dealing with stock losses, replacing or repairing damaged roads, bridges, houses and stormwater drains, and dealing with increased soil erosion and loss of soil nutrients can be formidable. Recent extreme weather events such as the Marlborough and Canterbury droughts, Cyclone Bola, the "weather bomb" in the Waikato/Coromandel area, and coastal flooding during the Waitangi Day storm, have shown how vulnerable our society and economy is to the weather and climate.
There are likely to be benefits and opportunities from a change in climate too. Farmers could benefit from better crop growing conditions and faster growth of pasture but greater fertiliser use would probably be needed. There could also be opportunities to grow new crops, with a longer growing season and fewer frosts.
However, if the rate and magnitude of climate change is not slowed down, that is, if we don't reduce greenhouse gas emissions, any beneficial effects of climate change are expected to diminish and the adverse effects and long-term risks expected to increase.
The climate in Nelson and Marlborough
As much of this region is sheltered by high country to the west, south and in some areas to the east, it is the sunniest region of New Zealand. Warm, dry and settled weather predominates during summer. Winter days often start with a frost, but are usually mild overall. Typical summer daytime maximum air temperatures range from 20°C to 26°C, but occasionally rise above 30°C. Late winter and early spring is normally the most unsettled time of the year. Typical winter daytime maximum air temperatures range from 10°C to 15°C. Annual hours of sunshine average at least 2300 hours. North northeast winds prevail in Nelson, while southwesterlies prevail about Blenheim. Nelson has less wind than many other urban centres and its temperatures are often moderated by sea breezes. High temperatures are frequent in Blenheim and may be accompanied by foehn winds from the northwest.
Last updated: 20 March 2008
