She was Chair of the Mentoring Physical Oceanography Women to Increase Retention (MPOWIR) and is the co-chair of the Scientific Steering Group that directs the work of CLIVAR.

Legg was born to a British father and a Sri Lankan mother and she was brought up far from an ocean in Zambia.

[2] She was a student at Wells Cathedral School[3] and at the University of Oxford, where she studied physics and graduated with first class honours.

[9] She has investigated the processes that underpin ocean mixing, including the breaking of internal waves, deep convection and gravity currents.

In 2015 she was one of the co-authors of an article published in Nature that looked at the internal waves in the South China Sea.