I go on expeditions for the same reason an estate agent sells houses - to pay the bills.

While I was serving, I worked as an adventure training officer, teaching soldiers how to ski, canoe and climb.

As a rule, anything that is pretty you avoid when on an expedition in the polar extremes. Normally anything other than white means a hazard such as a crevasse.

No one will pay you for planning an expedition at first: you have to work in pubs at weekends so you can pay the gas bills. I joined the Territorial Army, which paid me when I turned up to drill nights, and so did my wife.

Rivalry is one of the factors pushing me. While my back was turned, the Norwegians managed to achieve the first Arctic crossing in winter. I didn't want the same to happen in the Antarctic.