Summer temperatures in European cities have increased by up to 2.2 degrees since the 1970s but Dublin has warmed up by less than one degree, according to a recent report.
The World Wildlife Fund report of 16 European capitals showed average temperature rises of at least a degree in all cities except Dublin (0.7), Helsinki (0.8) and Copenhagen (0.2) in the summer months of 2001-2004 compared with 1970-1974.
Average summer temperatures in Madrid had risen by 2.2 degrees. London and Luxembourg were two degrees hotter, and temperatures in Athens and Lisbon increased by 1.9 degrees.
The report said the increases were above UN estimates for average world temperature gains and could only be partly explained by "heat islands" caused by growing urban populations. A build-up of gases from fossil fuels was more likely to be the main cause.
The conservation group is spearheading a campaign to encourage a shift to renewable energy sources.