Modelling climate change in the southern hemisphere
A project which sits at the heart of the Deep South Challenge is the development of the NZ Earth System Model (NZESM). An Earth System Model models our oceans, sea ice, land and atmosphere to understand how our climate will change under anthropogenic greenhouse gas emissions.
Fundamentally, the questions we are answering revolve around better understanding the Southern Ocean and Antarctica’s effects on climate and climate change and how we can better simulate it.
- The ongoing development of the NZESM has already shown the value of modelling with a focus on the Southern Hemisphere and the oceans around New Zealand. For example, research in these projects have improved projections of marine heatwaves around New Zealand, and reduced shortwave cloud biases across the Southern Ocean.
- Improvements made in the NZESM are being fed back to modelling teams in the Northern Hemisphere to improve the Unified Model, an atmospheric model that underpins many global climate and weather modelling efforts.
- Global modelling capability in New Zealand has grown, with scientific and technical expertise on climate modelling being established and supported across New Zealand.
How this research is being used:
- The establishment of the NZESM has enabled nuanced studies on how important climate processes are changing around New Zealand. For example, how climate change may impact the frequency and strength of storms that make landfall in New Zealand.
- Data from the NZESM have been used for research into larval connectivity modelling, and downscaled (regionally-relevant) data for understanding the meteorological conditions associated with extreme weather events. Downscaled NZESM data will be included alongside the updated climate projections for New Zealand that will be released by NIWA in 2024 for stakeholder use.
In the media:
- Silicon power, Water and Atmosphere (NIWA)
- New Zealand’s Next Top Model, New Zealand Geographic
- Breaking the ice, NIWA