- development and evaluation of process-based hydrologic models
- understanding the sensitivity of water resources to climate variability and change
- developing the next generation streamflow forecasting systems
- PhD, 1998: Geography, University of Colorado, Boulder, Colorado.
- MSc, 1992: Geography, University of Canterbury, Christchurch, New Zealand.
Martyn has authored or co-authored over 150 journal articles since receiving his PhD in 1998.