Tasman Lake Icebergs

Today we decided to take the opportunity to collect some ice samples from the Tasman Glacier Lake. This lake has been expanding rapidly over the last few years.

I took the first photo in 2002. See how much it has changed between then and today!

A few days ago there was a huge break-out of ice bergs from the end of the glacier. You can see them in the second photo. We were interested to get hold of some ice that would normally be out of reach deep below the surface, so we hired a boat with the Glacier Explorers and launched off with some insulated sample boxes and ice axes to go berg hunting...

It was an eerie feeling chugging slowly amongst the ice bergs, knowing that for every cubic metre of ice that we could see, there was another 9 metres of it under the water, ready to pop up from beneath at any time. Sure enough as we moved past one of the bergs a large chunk peeled off and a huge whale of a lump came surging up from below. Needless to say we got away as fast as we could! When the small tsunami had passed and things looked calm again we went back for a close up look at the ‘deep ice’, and managed to collect a couple of nice chunks to send back to the ice core laboratory freezer. Check out my exciting video of our iceberg adventure!

Home to Lower Hutt again tomorrow to start planning the logistics of our ice coring season.

My next blog will be in March when I take some students on a glacier science tour of the South Island. I hope you will join me to find out how we get on!

Aoraki Mount Cook ice core site reconnaissance

As well as having detailed discussions and poring over maps and images today, we took a ski plane flight to get a close up look at the possibilities. I have flown over the mountains of Aoraki/ Mount Cook National Park many times, but they never fail to impress. Have a look at my Mount Cook Fly-by video that I took as a record for our discussions...

You can see how dynamic the glaciers are – being very close to the Tasman Sea the mountains get huge quantities of snowfall. The glaciers cause rapid erosion of the shattered bedrock – hence the quantities of rock debris all over the place. Because of the fast ice movement down steep slopes there are lots of open crevasses – especially as we are at the end of the summer, where a lot of winter snow has melted back. Unfortunately these conditions make it very hard to find good ice core drilling sites which need to be high, stable, flat or dome shaped areas with no crevasses!

Aoraki Mount Cook ice core site reconnaissance

I am in Aoraki Mount Cook village with a group of scientists and others to help select the best possible sites for our ice core drilling season that is planned for June.

The people at the meeting all have valuable knowledge and experience to help in the selection – Amongst us there are glaciologists who have done research all over the world as well as New Zealand, an air pilot with detailed local knowledge, a Department of Conservation officer with extensive mountaineering and search and rescue experience. All of the people here have experience of working in the harsh, wild and remote conditions of the Southern Alps. Here I will introduce some of the team:

Uwe Morgenstern from GNS Science is the leader of the New Zealand Alpine Ice Core Expedition.

Trevor Chinn has an in depth knowledge of the glaciers of the Southern Alps.

Ray Bellringer works for the Department of Conservation and has an intimate knowledge of the mountains of the Aoraki / Mount Cook National Park, as well as an understanding of the hazards of the environment from his experience with the Search and Rescue team.

Paul Mayewski from the US is a pioneer of ice core and climate change research. He has led a number of major international research expedtions in Greenland, the Himalaya and Antarctica.