A "plastic soup" of waste floating in the Pacific Ocean is growing at an alarming rate and now covers an area twice the size of the continental United States, scientists have said.

One cigarette lighter, a toothbrush, a toy robot and a tampon applicator. The list of plastic items recovered from the stomach of a Laysan albatross chick that died on a remote Pacific island reads like a random assortment of everyday household objects.

Catkins and celandines; newts and nest-building blue tits; snowdrops and seven-spotted ladybirds – the signs are unmistakable, and all point to an undeniable conclusion. A full month before the official end of winter, the British springtime has most definitely sprung.

Nine ways in which the Earth could be tipped into a potentially dangerous state that could last for many centuries have been identified by scientists investigating how quickly global warming could run out of control.