Veteran climate scientists hopeful a historic Paris deal is only hours away

Anticipation builds for COP21 to deliver a groundbreaking deal as experts welcome draft statement to keep warming to well below 2C

There's a cafe next door to the thronging media centre at the UN global climate talks in Paris where the constant clang of the door to the chill air outside can barely be heard above the buzz.

Veteran climate scientist and biologist Prof Lesley Hughes has taken a seat with me close by and is struggling to hear herself think.