BBC NEWS - Arctic explorer in Thames trial

"I have been exploring the Arctic for 25 years and in this time I've seen the dramatic effects of global warming," Mr McNeill said.

"It used to be one solid sheet of ice that you could walk across.

"Now it's interspersed with stretches of icy water - if you look at it from satellite images it's like crazy paving, hence the need to build the Qajaq."

The Pacific Decadal Oscillation

...in this century, major PDO eras have persisted for 20 to 30 years...

2007: Jeremy Clarkson's drive to the north pole

I recently watched the 'Top Gear' special - where Jeremy and James May drove a specially modified Toyota Hilux pick-up to the magnetic North Pole from Canada's resolute bay!
That feat in itself is unbelievable, as it has never been done before: but what makes it so astonishing is that Jeremy and James managed to do it with a certain amount of ease.

1909: Peary talks about having to "cross and recross" open water in the Arctic

The difficulties and hardships of a journey to the North Pole are too complex to be summed up in a paragraph. But, briefly stated, the worst of them are: the ragged and mountainous ice over which the traveler must journey with his heavily loaded sledges...
...the open leads already described, which he must cross and recross, somehow...