Lisa writes from the Esperanza in the Atlantic Ocean

We're now in the Atlantic Ocean heading for Europe - escorted by sea gulls gliding alongside us as the swells rock us from side to side.

The Arctic was an amazing place to experience but the most beautiful part of our journey was seeing the south east coast of Greenland.

The mountains and glaciers there looked like something out of Lord of the Rings and we discovered an iceberg bigger than a football field - a perfect place for a banner we thought! Anais and Dean were the lucky ones to go onto the iceberg and they said it was quite a surreal experience. The surface was extremely hard and slippery and covered with little streams of water flowing through it. Anais told me she drank some water from one of the streams and that it was the best tasting water she ever had. Can you imagine - drinking water from melted ice that is thousands of years old? She also said she could hear the iceberg fizzing and popping all around them as they laid out the banner. Apparently this sound is called "Bergy Seltzer" and it's made by compressed gas bubbles being released as the ice melts.

I have never really thought much about icebergs until seeing them here for the first time but now I've become a little obsessed with them. And I've been wondering where they come from, why some of them have blue bits, how long they last for and if climate change is making more of them or less. I managed to catch Arne, our ice pilot, at dinner this evening and grilled him over the subject.

Here's a few cool facts I learned for those of you who are also pretty clueless about these wondrous icy things like me…

An iceberg begins its life as part of a glacier on land. Glaciers are basically massive pieces of frozen fresh water -- created when snow remains on land and builds up year after year, layer upon layer so that the snow crystals beneath are compressed more and more tightly - forming dense ice. Glaciers often move very slowly towards the ocean and break up into icebergs when they reach the coast or they form a floating ice shelf which gradually disintegrates into icebergs. Bergs can last several years depending on where they go. If they stay in cold waters they could float around for 50 years or more. The blue bits are where the ice is the most dense and all the gas has been squeezed out.

I've also been reading up about the effect climate change is having on icebergs. Turns out it is causing glaciers to flow faster and break up more into the ocean together with speeding up the rate at which floating ice sheets collapse. So we are actually seeing more ice bergs as temperatures rise.

Scientists say that Greenland's ice sheet is losing mass at an accelerated rate because it's melting more on top from warmer air, and it is dumping more icebergs into the ocean from warmer water as well as warmer air.

It's rather ironic that some of the ice bergs we've been admiring on our journey may not have existed if climate change wasn't happening. And one of the things Cairn Energy clearly struggles with - is "iceberg management". But they will only be bombarded with more of them as climate change worsens. Funny how nature could end up protecting itself by making more ice bergs to get in the way of the greedy oil industry. I hope a big piece of the massive ice island that broke off from Petermann glacier last month manages to make its way south and lingers right over Cairn's drill site so that they have to give up and go home. Wouldn't that be perfect?

It feels wrong that we've left Greenland while Cairn stays. I can't bare to think about what might happen up there if they don't stop what they're doing. While we wish we could have stayed and occupied the Stena Don again or perhaps taken on the Stena Forth drilling ship - there are other ways we can apply pressure to stop deep water drilling and that's why we heading for a meeting of politicians in Norway where they'll be discussing whether or not to impose a ban on new deepwater drilling. And meanwhile we are still campaigning against Cairn.