Contours of radial velocity (r = r_i + 0.64d)
Contours of radial field (r = r_o)

Astrophysical Fluid Dynamics

Led by Professor Keke Zhang and Dr Joanne Mason

Magnetic activity of the Earth and Sun has significant effects on weather, industry and climate change on Earth. Strong solar activity causes magnetic storms on the Earth, alters the orbits of satellites, disrupts communications, and brings down power systems. Many atmospheric conditions are strongly affected by solar activities while the geomagnetic field protects the Earth from the electromagnetic waves and other radiation from the Sun.

Our research within the Centre for Geophysical and Astrophysical Fluid Dynamics includes the understanding of many profound questions in geomagnetism and solar magnetism such as why the Earth's magnetic field can reverse its polarity and why the sunspots change with a period of about 11 years.
There are three major different areas covered by our research:

The first is the mathematical problem of fluid motion in rapidly rotating systems which is classical and central to the understanding of the evolution and dynamics of rapidly rotating stars and planets.  The fluid motion may be driven by thermal instabilities or by the effect of non-uniform rotation. We attempt to develop analytical mathematical theories that can explain the structure and amplitude of the fluid motion in rapidly rotating stars and planets such as fast zonal flows and giant stable vortices in Jupiter.

Second, observations in recent years have provided an unprecedented new insight into the large-scale fluid motion in planets and stars which have been accompanied by great advances in high-performance computing technology prompting increasingly sophisticated numerical models. We employ various numerical approaches, such as direct three-dimensional simulations on modern massively parallel computers, to study the properties of fluid motion taking place in rotating stars and planets.

Third, the intrinsic magnetic fields of the Earth and Sun are believed to be generated by convection-driven magnetohydrodynamic processes taking place in their conducting fluid interiors. Along with the advance of supercomputer technology over the past decades, we have increased our research activities in the large-scale numerical simulation of the convection-driven geodynamo and solar dynamo.  We have constructed a new generation of  the Earth and solar dynamo model, using a finite element method,  that  takes the full advantage of modern massively parallel computers and will be used to advances our understanding of how the solar and Earth's dynamo  are operating. Our research activity has been continuously supported by both NERC and STFC grants over the past two decades.


Academic Staff:  Professor Mitchell Berger, Dr Andrew Gilbert, Dr Tim Jupp*, Professor Andrew Soward, Professor Keke Zhang, Dr Kit Hung Chan

Visiting Honorary Professor: Professor Chris Jones

PhD Students: Xiaoya Zhan

*Also a member of Exeter Climate Systems (XCS).

Postgraduate research

We welcome enquiries from prospective postgraduate research students.

This diagram shows the lateral variation in S-wave velocity from a model by Guy Masters and others. Dark regions indicate anomalously low shear wave velocities and red/yellow indicates higher shear wave velocities.