From Sydney to London, spectacular fireworks displays have lit up skies across the world as 2015 year begins.The New Year started with a bang as an explosion of light from some 12,000 fireworks - weighing a combined 15 tons - filled the sky above London's South Bank - including spectacular blasts from the frame of the London Eye.The 11-minute display, which is said to have cost £1.8million and was accompanied by an electronic soundtrack, featured a poignant commemoration of the centenary of the First World War with bursts of red fireworks representing poppies.