Beaches in Korea usually open in late June or early July, but many are officially welcoming swimmers and sun worshippers from as early as Friday this year due to the higher-than-average temperatures.

Last year, four major beaches in the southern port city of Busan -- Haeundae, Gwangalli, Songdo, and Songjeong -- opened on June 1 for the first time. But now swathes of coastline along the eastern and western flanks of the country are following suit.

On the east coast, two out of six beaches in Pohang, North Gyeongsang Province are opening on Friday, around two weeks earlier than last year. On the west coast, Daecheon Beach in South Chungcheong Province also opens on the same day, around 20 days ahead of its traditional schedule. Mallipo Beach, also in South Chungcheong Province, will open on June 14, around 10 days earlier than before.

Rising average temperatures on the peninsula, and in local waters, are prompting the trend. The ocean around Pohang has already hit 19.7 degrees Celsius, up 3 degrees Celsius from this time in 2011. Water temperatures in Daecheon Beach are also 2 to 3 degrees Celsius higher.

Despite last summer's heavy rain and typhoons, the four beaches in Busan drew an extra 1.63 million visitors after they brought forward their opening dates, raising the total number of visitors there by 10 percent.

On a similar note, a number of beaches are also opting to close later than usual. Daecheon Beach plans to close at the end of September, with the schedule having been pushed back a month.