Extreme weather events predicted for Otago in long term – climate change report [RNZ, 10/03/21]

A milestone report detailing the risks that climate change poses to Otago including widespread flooding will be tabled this afternoon.
The Otago Climate Change Risk Assessment found that in the long-term, climate change put the region at risk of an increase in intense rainfall events, drought, coastal erosion and inundation, and more extreme heat days above 30 degrees Celsius in Central Otago.
The report also projected major implications for communities and the economy.
It will be presented at the Otago Regional Council committee meeting.
While the key findings are dependent on different time and emission scenarios, they include:
- Future annual average warming spans a wide range: 0.5C to 1.5C by 2040, and 0.5C to 3.5C by 2090.
- The average number of extreme hot days above 30C is expected to increase with considerable variability between coastal, southern and Central Otago while frost days are expected to decrease throughout the region. Under one scenario, the number of extreme hot days in Central Otago are projected to increase up to 30 to 40 days by 2090.
- A slight increase in annual rainfall in Otago is expected by mid-century, spanning up to 20 percent by the end of the century with the largest seasonal increases projected during winter.
- Extreme, rare rainfall events are projected to become more severe in the future under all four climate change scenarios.
- Coastal and some central parts of Otago are expected to see a decrease in annual dry days of two to six days with increases of two to 10 dry days per year for many remaining parts of the region by the end of the century.
- Daily mean wind speed is projected to decrease about the eastern coast and increase for inland areas.
- With increased emissions, average annual flows are expected to increase across the region by the end of the century.
The direct impact on communities may include increased exposure to hazards – heatwaves, flooding and fires – while the indirect social impacts include disruption to health services, social and economic factors including migration, housing and livelihood stresses, food security, socioeconomic deprivation and health inequality including mental health and community health effects, the report said.
“The effects of climate change will not be spread evenly across the population, exacerbating existing socioeconomic and ethnic health inequalities.”