Icebergs 2
Icebergs 1

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.

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.

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.

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.