Matt Patterson

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Matt Patterson

Graduate Student

I study the dynamics of the South Pacific split jet stream and am supervised by Tim Woollings at Oxford and Tom Bracegirdle at the British Antarctic Survey.

In austral winter (JJA), the jet stream over the South Pacific splits into two branches - a zonally orientated subtropical jet and a polar front jet directed south-eastwards. Both of these jets act as waveguides, steering storm systems eastwards towards South America or polewards towards Antarctica.

My research involves understanding the factors that shape the mean state, the variability of the jets and how they may change under climate change. I have recently been investigating the role that Antarctic orography plays in shaping southern hemisphere atmospheric circulation. Antarctica is covered with ice up to 3-4km deep, which appears to alter the behaviour of Rossby waves at high latitudes.

comparison_U500_JJA_NOROG2_1.png

Idealised simulations of the southern hemisphere atmospheric circulation in austral winter with (left) and without (right) Antarctic orography.

The above figure shows an idealised model simulation with (left) and without (right) Antarctic orography. In the absence of Antarctic orography, the split jet pattern seen in the left panel, is completely destroyed and the flow over the South Pacific stagnates. This work potentially has implications for both idealised and comprehensive climate modelling of the southern hemisphere in that the representation of Antarctic orography is clearly important in shaping the observed circulation.

I'm a tutor for the course 'C5: physics of the atmosphere and oceans' which is a major course for fourth year physics students.