Clouds & aerosols over the Southern Ocean

Cloud bank, photo by David Allen

Reducing biases in the representation of clouds and aerosols in the NZESM

Clouds have a massive effect on climate. Cloud cover reflects radiation from the sun that would otherwise be absorbed by oceans, raising their temperatures. Cloud cover can also act as a blanket, keeping warmth near the surface.

Despite their significant influence on climate, clouds represent one of the largest sources of uncertainty in modern climate models. For example, the frequency of clouds over the Southern Ocean is often underestimated, causing models to predict storm tracks incorrectly and warmer sea temperatures than actually observed. These biases also affect the sensitivity of the model to human-induced climate drivers, such as increasing greenhouse gases.

This project will improve our understanding of the chemistry and physics of clouds and aerosols in the Southern Ocean, by combining detailed measurements made during voyages with satellite observations and modelling studies. We recently completed our first measurement voyage on the RV Tangaroa, which saw researchers travel to the Campbell Plateau, while making measurements from the ship and launching instrumented balloons.

Improving our understanding of clouds and incorporating this understanding into the NZ Earth System Model is critical, as these processes significantly affect New Zealand’s climate and have influences as far away as the tropics.

Project contact: Adrian McDonald, University of Canterbury
Project budget: $1.8 million
Project duration: 2015 – 2019

This project in the media:
New Zealand's Next Top Model, New Zealand Geographic
New Zealanders out to uncover icy secrets,
Breaking the ice, NIWA

Research and findings:
Shipborne and ground-based observations of clouds in the sub-antarctic and Southern ocean, Peter Kuma et al, Antarctic Science Conference Dunedin
Clouds and aerosols: Understanding processes –informing models, Mike Harvey et al, Deep South Symposium
Clouds and aerosols: a modelling perspective, Vidya Varma et al, Deep South Symposium


Return to the Processes and Observations programme page
​​​​​​​Check out the full list of Deep South Challenge projects

Latest news and updates

Creating a climate-safe Dunedin through community-driven climate action

2018 may well be the year New Zealand gets serious about adapting to our changing climate. Last year, and the start of this one, gave all of us plenty of opportunities to experience a future in which creeping sea level rise and extreme weather – from drought to flood to surprise storm surges – make day-to-day life more precarious and more expensive.

Stormwater, wastewater and climate change: Impacts on our economy, environment, culture and society

In October 2017, the Deep South Challenge released a report into the state of the nation’s storm and waste water infrastructure, in the face of a changing climate. The report garnered significant media attention – not surprising given the infrastructure is currently valued at well over $20 billion.

The Deep South Challenge awards funding to investigate climate-resilient, high-value crops for the whānau of Omaio

The whānau of Omaio in the Bay of Plenty have joined forces with NIWA researchers to explore the viability of climate-resilient, high-value crops for the rohe. The group has won a $250,000 research grant under the Vision Mātauranga programme of the Deep South National Science Challenge to better understand Omaio’s changing climate and how it might support the community to create a local economy based around a high-value product like kiwi fruit.