I was up on the bridge all night helping out with a glacier survey we are conducting for a scientist at a university in the UK. The scientist arranged for a satellite picture of Scoresby Sound to be taken last night at 23:15. Our job was to count and document all of the icebergs in the satellite image.

The data we collect will be compared with the satellite photo, which in turn will help the scientist adjust his models based on the difference between what he sees in the satellite photo and the data we collect.

Iceberg behavior - how they travel and degrade over time - is an indicator of global warming. As the Greenland ice sheet warms, its glaciers move faster towards the sea and discharge more ice into fjords.

We took a photo of each berg and used the radar to measure each one's distance from the ship and the size at its base. We recorded each berg's GPS coordinates and its shape (tabular, sloping, dome-shaped, weathered or glacial). This took from midnight until around 09:30 this morning, so by the time we were finished, I'd been up for 24 hours and definitely needed some sleep.

Polar bear with an escort

So I hit my bunk for five hours and when I woke up, I trundled bleary-eyed up to the main deck, looked outside and saw Thomas in a survival suit escorting a polar bear by the arm across cracks and around melt pools in a huge ice flow. It was very surreal and quite an unusual sight.

When I went to bed earlier this morning, the rest of the crew set up two photo shoots that will hopefully be used around the upcoming G8 meeting.

Bernard (deckhand from Canada) used charcoal to draw a 14 x 18 meter (15 x 20 yard) polar bear and a 20-meter (22 yard) square United States flag on the ice flow with the words, "SAVE ME" beside it. While he was doing that, John (who works with Lonnie and Eric at One World Expedition and is on board helping us with logistics and safety) dressed up in a polar bear costume, and was photographed on the ice flow holding a banner that read, "SAVE ME." The polar bear suit looks fantastic but doesn't allow the wearer to see much of anything, so John had to be guided by Thomas, a deckhand from Norway, across the ice.

Even though it looked like a bit of a comedy to watch a person escorting a polar bear across an ice flow, the threat of global warming is very real and not too far off in the distance. If scientific models are right, polar bears could be extinct by the end of the century if warmer temperatures result in an ice-free Arctic in summer. That's in my lifetime. It's a very grim thought.

We are now crunching through ice toward Ittoqqortoormiit on the north side of the entrance to Scoresby Sound. Our ETA (estimated time of arrival) is some time before midnight. I'm looking very much forward to seeing how village life in Greenland compares with village life in Alaska.

- Melanie