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Geographic Coverage: The report covers the Wellington Region. 

Summary: 
This report outlines expected climate changes in the Wellington Region based on projections to 2040 and 2090. It highlights key changes in temperature, rainfall, sea level, agriculture, biodiversity, and infrastructure. 
 
Temperature is expected to rise across all seasons. By 2040, warming of up to 1°C is projected, with autumn seeing the most increase. By 2090, Masterton may experience up to 3.5°C warming in autumn, and the region overall may see increases of 2–3°C. The number of hot days (above 25°C) will rise significantly, especially in Wairarapa, which may see an increase from 24 to 94 days per year, and from 6 days to 26 days in the west of the region. 
 
Rainfall patterns will change. Eastern areas like Masterton may see a 10–15% decrease in spring, summer, and autumn rainfall by 2090, increasing drought risk. Western areas may experience more rainfall, particularly in winter by up to 15%. Extreme rainfall events are expected to intensify due to a warmer atmosphere. 
 
Sea levels are rising. Wellington has seen a historical rise of approximately 2.2 mm per year. Globally, sea levels could rise between 0.28 and 0.98 meters by 2100, with higher increases possible if the Antarctic ice sheets destabilise. Coastal areas may face more frequent storm inundation and erosion events. 
 
Agriculture will be affected. Growing degree days will increase, especially in Wairarapa, potentially making it similar to Northland by 2100. While new crop opportunities may emerge, droughts could limit productivity and affect livestock. Native species may shift their ranges and face increased competition from pests. Forest fire danger is projected to rise by 100–150% by 2090. 
 
Infrastructure and communities will face challenges. Water supply may be stressed without additional storage. River flows may decrease in the east and increase flood risks in the west. Adaptation strategies include managed retreat, coastal fortification, and planning for sea level rise. 
 
Greater Wellington Regional Council is taking action through its Climate Change Strategy and various projects, including flood protection, hazard management, catchment modelling, and water planning.