Programme

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.

This is a joint project with the ESMP programme.

This project in the media:
New Zealand's Next Top Model, New Zealand Geographic
New Zealanders out to uncover icy secrets, Scoop.co.nz
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