Global Challenge
Week 26 - The Southern Ocean

It's four weeks now since the fleet of twelve yachts crossed the start line in Sydney Harbour, bound for Cape Town. This is leg four of the Global Challenge and was always recognised as being the toughest of the whole circumnavigation. Throughout the leg, the range of weather conditions has been remarkable, as has the speed with which they have changed.

As we are engaged in a highly competitive yacht race, there is always a drive to sail the shortest distance as quickly as possible. In an effort to stop crews diving south into Antarctic waters to reduce the distance sailed, a waypoint was inserted en route, which had to be left to port. This ensured a passage to the north of the Kegeulen Islands, but even so, routing into waters prone to icebergs was still possible.

Summer is fast coming to a close in the southern hemisphere. The standard pattern is for high pressure areas to sit in an almost continuous belt across 35-45 degrees South, with vigorous areas of low pressure sitting further south, between 45- 55 degrees.

This race is unique in that it requires competitors to complete a circumnavigation against all the main prevailing winds and currents. Nowhere is this more readily illustrated than on this particular leg. Yes, there's plenty of wind, but most of it blows from a westerly quarter, forcing the yachts to tack across the wind to make headway.

I suspect we've escaped lightly thus far. Only once have we seen winds approach 50kts, although the region does produce gale or near gale force winds for days on end. The constant slamming of yachts into these conditions can be extremely wearing I assure you.

Between the lows, transient ridges can be equally frustrating. One expects to be becalmed in the Doldrums, but not at 52 degrees South! Forecasting such events is obviously crucial and has certainly kept me busy.

Numerical models are the standard tool and seem to have a few failings in these regions. Wind strength is generally underplayed. The major failing, however, is an inability to detect the more subtle vagaries, which seem crucial to my present customers, my crewmates.

With water temperatures as low as 4-5C and windchill close to -20C, the Southern Ocean has left its mark on us all. Time on deck has often been limited to 30 minutes, despite many layers of high quality clothing. What must it be like here in Winter?!