With only two weeks to go before crucial climate talks in Copenhagen, there are worrying signs the planets ice caps are melting much faster than previously thought. One survey crew are using the latest laser technology to map the surface of Antarctica’s changing ice shelves. Since 2006, they say the continent has been melting quicker and that the rate could even speed up with global temperatures predicted to rise.Columbia University researcher Michael Studinger said: ‘‘We know that all the ice shelves in Antarctica along the Antarctic peninsula are melting rapidly, and they’re melting all at the same time and they are not only melting faster and faster every year but the melting is penetrating further inland every year, that is the big concern.’‘ Environmentalists will be hoping the new evidence will concentrate world leaders’ minds. There is some room for optimism after the White House yesterday pledged to take a target to reduce carbon emissions to the Denmark summit. The size of that cut is being eagerly awaited with hopes it will prompt other big emitters to announce their own targets.