Project information
Project aim
Gravity waves are atmospheric waves that play a critical role in defining the dynamical state of our atmosphere. Numerical models cannot fully describe the atmosphere without including these waves, however, their small scale makes it difficult to represent them directly; parameterization schemes must be used. At present, the poor quality of these parameterizations limits models’ ability to accurately represent stratospheric ozone change and its consequences for our weather.
Improvements to gravity wave parameterization are challenged by a struggle between complex source, propagation and breakdown processes, and the need for computationally simple representations.
This project seeks to improve climate models by improving gravity wave parameterization schemes. Specialized modelling will allow us to condense the complicated physics of gravity waves onto simpler sets of parameters. These will be trialled in Australian and international climate models.
Project milestones
Summary of the season 2021/22
Waves play an important role in forcing air movements in our atmosphere. Some of those waves fall between the cracks of model resolution and need to be added in through a process called parameterization. The challenges of representing these small-scale waves in climate models have existed since these waves were first added to model codes. Since then, models have grown more sophisticated and much has been learned about the waves.
Recent observations suggest that the characteristics of small-scale waves are not what was expected when models were first formulated. The models also need to be able to track wave source changes in a changing climate. These two factors have made it necessary to rethink small-scale wave representation.
This project is doing just that. With an eye on both model design and recent observations, a strategy for transition to a new generation of wave representations has been formulated. New ways of doing things are being incorporated into a model for testing. They provide a clear path from enhanced knowledge of waves to further improvements in model performance. They also allow for the incorporation of recently recognized sources due to secondary wave generation.
Model testing is still underway and long-running challenges are still apparent. But through our efforts we expect to enhance our knowledge of the role small-scale waves play in driving the high-latitude atmosphere.
Summary of the project achievements 2020/21
Waves play an important role in forcing air movements in our atmosphere. Some of those waves fall between the cracks of model resolution and need to be added through a process called parameterization. The challenges of representing these small-scale waves in climate models have existed since these waves were first added to model codes. Now, models have grown more sophisticated and more has been learned about the waves.
Recent observations suggest that the characteristics of small-scale waves are not what was expected when models were first formulated. The models also need to be able to respond to wave source changes in a changing climate. These two factors have made it necessary to rethink small-scale wave representation.
The project has done just that. With an eye on both model design and recent observations, a new wave representation has been formulated that focuses on the intense waves we now know are dominant. It provides a clear path from enhanced knowledge of waves to further improvements in model parameterizations. It also opens the way to including processes where 'secondary' waves are created as they travel through the model.
Model testing is still underway and long-running challenges are still apparent. But through our efforts we expect to enhance our knowledge of the role small-scale waves play in driving the high-latitude atmosphere.
Summary of the season 2019/20
The challenges of representing small-scale waves in climate models have existed since these waves were first added to model codes. Since then, models have grown more sophisticated and much has been learned about the waves.
However, recent observations suggest that the characteristics of small-scale waves are not what was expected when models were formulated. They also have a strong reliance on meteorological process. Models need to be able to track wave source changes in a changing climate. These two factors have made it necessary to rethink small-scale wave representation.
The current phase of this project is doing just that. With an eye on both model design and recent observations, a strategy for transition to a new generation of wave representations has been formulated and refined. New ways of doing things have been suggested that should create a clear path from enhanced knowledge of waves to further improvements in model performance.
Model testing is underway and preliminary results suggest some of those long-running challenges are still apparent. But through our efforts we expect to enhance our knowledge of the role small-scale waves play in driving the high-latitude atmosphere.
Summary of the season 2018/19
The challenges of representing small-scale waves in climate models have existed since these waves were first added to model codes. Since then, models have grown more sophisticated and much has been learned about the waves.
However, recent observations suggest that the characteristics of small-scale waves are not what was expected when models were formulated. The models also need to be able to track wave source changes in a changing climate. These two factors have made it necessary to rethink small-scale wave representation.
The current phase of this project is doing just that. With an eye on both model design and recent observations, a strategy for transition to a new generation of wave representations has been formulated. New ways of doing things have been suggested and are being incorporated into the models. They should create a clear path from enhanced knowledge of waves to further improvements in model performance.
Model testing is still underway and those long-running challenges are still apparent. But through our efforts we expect to enhance our knowledge of the role small-scale waves play in driving the high-latitude atmosphere.
Summary of the season 2017/18
The challenges of improving the representation of small-scale waves in climate models is ongoing but in the first year of this four year project, the groundwork is being laid to meet these challenges.
Preliminary work for high-resolution modelling of waves generated on and near the Antarctic coast is underway. Combined with our observations, it will be possible to investigate the triggers of wave generation and the key characteristics of the waves that are made. A framework for model development has also been proposed that will aid the transfer of observational results to parameterization schemes. These tools will allow us to capture the role of high latitude waves in models and better predict change in our atmosphere.