The CRU data set.
Solar activity.
Greenland ice cores.
Scientist opinions.Historical observations:
HISTORIC VARIATIONS OF ARCTIC ICE (MUCH MORE AT THE LINK)
THE ARCTIC IS MELTING
“It will without doubt have come to your Lordship’s knowledge that a considerable change of climate, inexplicable at present to us, must have taken place in the Circumpolar Regions, by which the severity of the cold that has for centuries past enclosed the seas in the high northern latitudes in an impenetrable barrier of ice has been during the last two years, greatly abated….
….. this affords ample proof that new sources of warmth have been opened and give us leave to hope that the Arctic Seas may at this time be more accessible than they have been for centuries past, and that discoveries may now be made in them not only interesting to the advancement of science but also to the future intercourse of mankind and the commerce of distant nations.” A request was made for the Royal Society to assemble an expedition to go and investigate.
President of the Royal Society, London, to the Admiralty, 20th November, 1817, Minutes of Council, Volume 8. pp.149-153, Royal Society, London. 20th November, 1817.(from) http://www.john-daly.com/polar/arctic.htm
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“Whalers in the North Atlantic in 1815 and 1816 described an unprecedented breaking up of the ice in the Davis Strait, that had apparently sent icebergs as far south as 40°N. The prevailing theory held that seawater could not turn to ice (supported by observations that melted icebergs released fresh water), and therefore that all Arctic ice formed around coastlines. It further held that the waters around the North Pole might therefore be ice-free, forming an Open Polar Sea
If the barriers of ice surrounding this open sea were breaking up, then there might be an opportunity to sail across the top of the North American continent, either by by the proposed Northwest Passage, or perhaps by sailing north past Spitzbergen, across the Polar Sea, and down through the Bering Strait.”
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From Wikipedia;
“John Barrow, the Second Secretary to the Admiralty encouraged interest in the possible existence of a Northwest Passage.With the support of Sir Joseph Banks, he prepared two simultaneous expeditions, one to be led by John Ross, heading West through the Davis Strait, and the other to be led by David Buchan, taking the polar route. An arrangement of prizes for acheivement both West and North were adopted by an Act of Parliament in 1818. Thus began a series of expeditions that lasted for sixty years.”
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“The uncharted coastline of east Greenland became clear of ice around 1820, and in 1822 Scoresby, in the midst of an arduous whaling voyage, sailed along some 400 miles of this inhospitable landscape, charting it, and naming point as he went in honour of scientific and other friends, chief of which was Scoresby Sound, named for his father. Almost all his place names survive today.”
That Scoresby junior was a man to be believed when he claimed that the arctic was melting can be further seen here in this extract;
“Carrying on with great success the most demanding and arduous of all maritime activities -the hunting and capture of whales – he yet col
