内容摘要：But it may be disrupting species' breeding patterns and could bring an influx of jellyfish that like warmer waters, including the huge barrel jellyfish, to seas and beaches.

But it may be disrupting species' breeding patterns and could bring an influx of jellyfish that like warmer waters, including the huge barrel jellyfish, to seas and beaches.

A Gavin & Stacey themed postbox topper, which appeared in Hay-on-Wye to mark an appearance by the stars of the show, has been vandalised twice in a week, its creator has said.Last week, the postbox - painted gold in honour of Paralympics discus champion

- was decorated with two crocheted figures of main characters from the hit TV comedy.James Corden and Ruth Jones, who wrote and starred in the show as Nessa and Smithy, were at the Hay Festival talking about their new book.There was concern when the postbox topper disappeared this week, but its creator Reet Prendergast said it was being repaired after being damaged for a second time on Wednesday.

Passers-by spotted the woolly figures of Smithy and Nessa had vanished, leaving just the two posts where they once stood and Nessa's catchphrase, "oh, what's occurring", embroidered below."I came up one day and someone had snapped Nessa's legs. So I took her home to fix her and then put it back on again and then Smithy was broken as well, very sad, so I've taken them off home," Ms Prendergast said.

She added that she tried to make a new topper every month, and in the 18 months she has been doing it, this was the first time one had been damaged.

Ms Prendergast, however, said Smithy and Nessa would be back on back on top of the post box next week."Pretty dramatic things [are] happening in both west Antarctica and Greenland," said co-author Prof Jonathan Bamber, director of the Bristol Glaciology Centre.

East Antarctica appears, for now at least, more stable."We're starting to see some of those worst case scenarios play out almost in front of us," added Prof Stokes.

Finally, scientists use computer models to simulate how ice sheets may respond to future climate. The picture they paint isn't good."Very, very few of the models actually show sea-level rise slowing down [if warming stabilises at 1.5C], and they certainly don't show sea-level rise stopping," said Prof Stokes.