global warming is just a natural cycle

Telegraph News Global warming ‘just a natural cycle’: “Global warming comes and goes in 1,500 year cycles which may have more to do with cosmic rays than fossil fuel emissions, according to a new book.
If the genuine warming now being seen is caused by human emissions of carbon dioxide, it would have started earlier, according to the book by two veteran American climate sceptics, Fred Singer and Dennis Avery.
Mr Avery, who was in London yesterday, said: “If this were a CO2 driven warming it should have started in 1940 and risen strongly from there. In fact warming started in 1850 and rose sharply until 1940 then decreased for 35 years.” “