In the last two days the sea temperature has dropped below nine degrees and we have seen five icebergs pass close by. The first two were quite large and passed about half a mile either side of the boat, the last 'growler' was no bigger than a small car and we missed it by five boat lengths.
This has reinforced to me how small we are and how far from any help we are should anything go wrong. Right now, approximately halfway across the Pacific Ocean, we are almost at the furthest point from any land.
Life on deck is conducted in survival suits, hats and gloves, while below deck the freezing cold hull acts like a refrigerator for all inside.
Over the last week there has been a big divide between boats in the north and others in the south as boats ahead were able to cross in front of a light wind ridge of high pressure and those behind were forced to skirt it to the south.
This is what has pushed us down into the ice when the compulsory ice gates are there to keep us north. It has been a period of the 'rich getting richer' and the gaps between boats have increased throughout the fleet. From now that should stop and possibly reverse as the leaders sail into headwinds.
Listen to Stuart Alexander speak to Ian Walker via satellite link-up
The larger the gaps between boats the more inclined you become on concentrating on your own race. This has always been our strategy but, as we approach Cape Horn, we have more of a mind on seamanship and survival than squeezing the last mile out of every position report. To say that we are taking our foot off the gas would be wrong - we are simply trying to see the bigger picture.
The boat is the quietest I have known it as it is cold and windy on deck and all the time below deck is consumed with getting dressed or undressed, eating and sleeping. It feels like everyone is in their own survival mode for now.
In two days' time we will have been at sea for a month, my longest ever period at sea, but life onboard is too busy to sit and ponder this. Time is moving on - days merge into weeks.
The only thing that is starting to get to me and others is the food. We have not packed enough food either for these cold temperatures or for the extended length of this trip. I am not going to ration anything until after Cape Horn, as we will need all our strength.
I am already dreaming of a large Argentinian (or should that be Brazilian) steak and I suspect the last week into Rio could well be a very hungry affair. We will see then how strong the team spirit really is.
Ian Walker has won two silver medals at the Atlanta and Sydney Olympic Games and was skipper of the Team GBR challenge for the America’s Cup in Auckland in 2003. Now he is skipper of the Galway-based, Chinese-partnered Green Dragon team in the Volvo Ocean Race and is writing an exclusive commentary for The Independent plus talking to Stuart Alexander by satellite link from the boat during the 10 legs and 37,000 miles that take the fleet from Spain around the world to St. Petersburg.