Icebergs 2
Icebergs 1

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1/ Heavy pack ice and grounded icebergs

This kind of ice looks smooth from a distance, but is very hard and slow going to traverse. It is made up of last years pack ice (frozen sea-ice) that broke up, partially melted and became far from a smooth surface during the summer. Now, in the winter, the random shaped, uneven pieces have been cemented together by frozen sea water in between. The result is a very rugged surface where the quickest way to travel is by foot, vehicles or skis require so much continuous stop-start and change of direction that they actually slow you down.

The long pole carried by the figure in the picture is known as a "bog chisel". It is a 6ft pole with a 3" wide unsharpened chisel blade on the end used to test the strength of sea-ice. If it takes three or more hefty "thwacks" to get through the ice to the sea beneath, then it is safe to walk on. If not, then it is a case of very carefully and slowly re-trace your steps to the last place where it was safe.

2/ Raspberry ripple snow

OK not an iceberg at all, but part of a land-based snow slope. In the spring when the winters snow begins to melt, water flows across the top of glaciers and snow slopes carrying with it dissolved nutrients in the melt water. In these conditions, algae grows within the top layer of the ice or snow catching the goodies as they flow by and taking advantage of the extra energy from the longer days and stronger sunshine.

In this case the algae is predominantly a red-coloured species, but further down the slope, green and blue-green colours are discernable. This is relatively short-lived spring phenomena as soon the very snow and ice layer that the algae are living in will melt and the algae will flow down to the sea with the water that provides them with their nourishment. It is not unusual to see distinctly red, green or blue-green topped ice bergs in the spring as a result of the growth of such algae.

3/ Aren't I small and isn't this big

It's quite a humbling experience standing close to an ice berg the size of an office block, particularly when you consider that the bit beneath the thin sheet of ice you're standing on is the size of 8 or 9 office blocks.

The whole scale of Antarctica is really quite awesome, such moments and places serve to remind us that we are really quite insignificant to the motions of the planet. These motions that took place before we "discovered" them, continue oblivious to our presence and will still continue when we are no longer around to see them.

4/ Sunset behind pointy berg

Ice bergs are carved and shaped by wind and wave. As they are eroded, so the balance changes and they tip up to a new stable position. This continuous erosion, moving around and occasional breaking up into smaller pieces produces all kinds of weird and wonderful shapes that belies their original origin as a part of a flat freshwater glacier.

5/ Berg wash

Ice bergs are eroded by a combination of temperatures above freezing and the effects of wave action. Here in a fairly rough sea, waves are washing up the side of this berg to a point about 2 metres above sea level and will probably make two separate upright areas that are divided by the developing trough. We did for a short time consider trying to speed through the gap when it was awash in our small powerfully driven zodiac boat, but decided against it - probably for the best!

6/ Cubist berg

The hard angular shapes and edges of this berg remind me of a cubist painting. Notice that the area at sea-level towards the left is very smooth and curved by contrast to the rest of the ice. The sharp geometric edges will probably have been made when this piece of ice calved from its glacier, the fracture planes of the ice being usually straight and plate-like. That it is not yet smoothed out indicates that this region has not yet been under the water to be sculptured into the more usual curves seen on ice bergs, it also means that it only recently fell off the glacier, although it could well be a fracture plane from the collapse of a larger ice berg that broke into pieces

7/ Berg visit

It can be quite an unreal experience getting close up to ice bergs in small boats but a really awesome if potentially dangerous thing to do. The effect of light on and through the ice produces a world of blues and white, the berg can usually be seen for several metres below the water surface and there may be icicles hanging down as here where the ice has melted in the sun and water run across the face of the berg before freezing again. If you ever end up in this situation, make sure you have some really good sunglasses and a high factor sun screen for exposed flesh (including that little bit underneath your nose!) as the reflections and brightness especially when the sun comes out can be painfully dazzling with no-where to look that isn't brilliantly lit.

Large irregularly shaped bergs tend to be the most interesting to visit, but also the most dangerous and most unstable. They will break up at some point and they will tilt and move around a lot before settling to a new stable position. If you're in the vicinity when this happens, you may get some big pieces of ice dropped on you or at the very least there will be some major waves and disturbances of the sea. Having said that I've never heard of anyone actually being hurt in such an event - a combination of the rarity of it happening, alertness and speed of the boatman/boat and people just not going near big bergs very often in small boats.

Icebergs 1 Antarctica Fact File Index

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