Christian Jakob

Working smarter and harder to tell the weather

Professor Christian Jakob is interested in models - that is, climate models - and how scientists around the world can work together better to improve them. He has worked for organisations as varied as the United States Department of Energy, the European Centre for Medium-Range Weather Forecasts, and the Bureau of Meteorology. He is currently the Deputy Director of the Australian Research Council's Centre of Excellence for Climate System Science, where he is studying the effects of tropical convection on Australia's climate - how clouds affect weather.

Christian has studied the weather in some of the only places in Australia where rainfall rates have recently been increasing, rather than decreasing. He is also looking at the little-understood Southern Ocean, and pushing for a comprehensive temporary cloud measurement station on Macquarie Island.

"Some people believe that the clouds over the Southern Ocean are major drivers in the uncertainty surrounding climate change predictions. The other reason [I'm interested in it], though, is just out of curiosity - we know so little about that area."

Christian has also helped to standardise the 'language' with which climate scientists in Australia communicate.

"We now have, as a nation, one climate model for the university community, the Bureau of Meteorology and the CSIRO to work on, which is quite a novel thing for Australia. In the past we were too fragmented, but we've since come to appreciate as a community that by using the same model for weather prediction and climate, we can take what we've learned on one end, and apply it to the other."

The result has been the establishment of the Australian Community Climate and Earth-System Simulator, or ACCESS, which will enable climate change scenarios over the 50-plus-year horizon.

Christian is also involved in the Centre for Water Sensitive Cities, making Melbourne more resilient to changing rainfall rates, the urban heat island effect, and most importantly, our own ignorance.

"The more you zoom in - from the level of the planet as a whole to a city - the more uncertain the problems become. It's important to confront that uncertainty. Sure, we want to make predictions - but we also want to predict the uncertainty of those predictions. Sometimes it's simply better to make yourself flexible against many possibilities - even if some don't bear thinking about - than rely on what could turn out to have been a wrong prediction."

As much as he emphasises the importance of good climate modelling practices and policy, Christian recognises that there are some significant hurdles to those wishing to make inroads into the field.

"Because climate models have been evolving for 40-odd years now, they're incredibly complex - which scares people off even more - and it's almost impossible that even PhD students do anything more than just learn the ropes; there's simply not enough time. We make decisions worth trillions of dollars based on climate models, though, and they deserve our best talent. This is where the ARC Centre of Excellence for Climate System Science is great, because we have a seven-year funding cycle, and so we get to tackle the big problems."

In spite of all this, Christian knows when it is time, both for him and for his students, to get out of the office.

"After my university education, I was a research scientist in charge of modelling clouds and tropical convection, and in that entire time I managed to go without having ever seen what tropical convection looked like. I've learned from that. Now I always make sure that my students get out and be part of an experiment to measure what they're actually studying."