It looks like a joke postcard, but experts say this is the fate which could befall Brighton unless global warming is curbed.

The postcard shows floodwaters overwhelming the Royal Pavilion and a small boat passing within feet of the palace.

The Energy Saving Trust said there is a serious message behind the card.

David Hamilton, director of energy efficiency said the image showed what could happen by 2050.

He said: "The images we're presenting are an artistic interpretation of what might happen. However, climate change is a reality - the recent floods and freak storms in the UK are just a foretaste of what is to come.

"The more energy we use at home, the more we're damaging our environment.

"On average each home in the UK releases six tonnes of carbon dioxide into the atmosphere each year - that is more than the annual emissions from the average car.

"The message is simple - start being energy efficient now to avoid scenes like these in the future."

The Brighton postcard is one of a series showing water rising around familiar landmarks such as the Angel of the North and the Millennium Dome.

Rik Child, a green councillor at Brighton and Hove City Council, said: "The Energy Saving Trust is extremely well-respected. We will have a sea level rise but I very much doubt the Pavilion will fall into the sea in 50 years.

"This might be an exaggeration to make a point, but we can probably kiss goodbye to seafront developments in Brighton in the next 50 years.

"We are already seeing weather events around the world which are more dramatic. The sea level rise could be between 20cm and 50cm in the next 50 years."

The Pavilion postcard picture can be sent with personal messages to friends and relatives online at www.saveenergy.co.uk.