all the proof you need

Sunflowers are normally associated with warmer climates and scientists believe that global warming is responsible for allowing them to grow successfully in the northern isles. They were grown by Richard Herdman, an Orkney farmer, who scattered the seeds over two and a half acres of his dairy farm in the west Mainland area.

Ruth Dawkins, of the Stop Climate Chaos group, said the success of the sun-loving yellow flowers on Orkney was a sign of global warming.
The Telegraph (UK), 14 Oct 2008

statistics that are not to be sneezed at

Pollen seasons as well as the amount of pollen in the air progressively increased during a six-year study in Italy, the doctors told a meeting of the American Academy of Allergy, Asthma & Immunology in New Orleans.

“By studying a well-defined geographical region, we observed that the progressive increase of the average temperature has prolonged the duration of the pollen seasons of some plants and, consequently, the overall pollen load,” Dr. Walter Canonica, who worked on the study, said in a statement.The Telegraph (UK), 1 Mar 2010

flower miles warning

In the past three years, the amount of flowers imported from the Netherlands has fallen by 47% to 94,000 tons, while those from Africa have risen 39% to 17,000 tons. Environmentalists warned that ‘flower miles’ could have serious implications on climate change in terms of carbon dioxide emissions from aeroplanes.

Andrew Sime, the policy director of the New Economics Foundation, said, “There are plenty of flowers that grow in Britain in the winter and don’t need to be hot-housed. “Air freighting flowers half way round the world contributes to global warming.”
Daily Telegraph (UK), 10 Feb 2007