Climate Change Science Presenter: Nathan Ross, ICLEI-A/NZ Source: Dr. Andy Reisinger, Ministry for the Environment Communities for Climate Protection® - New Zealand: A New Zealand Government initiative delivered by ICLEI-A/NZ. This programme is part of ICLEI’s international Cities for Climate Protection® Campaign.

Definitions: The Greenhouse Effect Global Warming Climate Change

A look at long time scales – ice ages and our future Source: CDIAC data center. Jouzel et al., Nature 399: 429-436

A look at long time scales – ice ages and our future Source: CDIAC data center. Jouzel et al., Nature 399: 429-436

A look at long time scales – ice ages and our future Source: CDIAC data center. Jouzel et al., Nature 399: 429-436

A look at long time scales – ice ages and our future Temperatures will rise in response to the rising greenhouse gas concentrations. CO2e concentrations are going into territory they have not been in for 20 million years. Source: CDIAC data center. Jouzel et al., Nature 399: 429-436

Climate change – the immediate context – 1000 AD to 2100 AD

A look into the distant future – Why act now? CO2 concentration, temperature and sea level will all continue to rise long after emissions are reduced.

Climate change effects for NZ: Sea level rise: by 2100, a 30-50 cm rise is most likely. (14-17cm rise over 20th century) Temperatures: 1°C increase by the 2030s and 2-3°C by the 2080s (0.7°C increase over the 20th century) Rain: more to fall in the west of the country, and less in the east – also more risk of heavy rainfall Westerly winds to become more prevalent

Climate and Weather Extremes: Local impacts of climate change may be felt most in extreme weather events A small change in the average can lead to large changes in the extremes Increase in frequency and severity of natural hazards (floods, storms and drought), and the costs of these events - heavy rain up to 4 times as frequent by 2070

What will these changes mean? Climate Change will bring some opportunities to NZ: Warmer winters to increase hydroelectric lake levels Agricultural and forestry productivity to increase in some areas, also commercialisation of new crops Health benefits and lower heating costs with warmer winters

What will these changes mean? Climate Change will increase risks to NZ: Agricultural and forestry pests and diseases Water shortages, increased risk of droughts Higher temperatures affect some crops Heavy rainfall puts pressure on drainage and stormwater systems, increase in flood risk Biodiversity – some species will fail to adjust to a changing climate, ie. changing habitat

RMA Amendment RMA Amendment (March 2004) requires consideration of the effects of climate change in decision-making Planning for natural hazards, resource use, land-use planning and designing new infrastructure and assets Of particular importance are: development decisions in areas prone to river and sea flooding housing / infrastructure decisions in areas prone to coastal erosion water use rights / irrigation scheme placement and design infrastructure and asset design

top end bottom end

Historical trend No change

top end Planning on the basis of historical data only is not a robust approach. We need to take climate change into account to plan for the future. Data