Summer starts a half month earlier and lasts longer compared with 50 years ago due possibly to global warming, the weather agency said Sunday.

Summers in the 2000s started on average on May 27, 15 days earlier than those during the 1950s, the Korea Meteorological Administration said, citing previous data.

With the early start of summer, the length of summer has been extended by 20 days for a total of 121 days on average since 2000 compared with the 1950s, the weather agency said.

The agency defines the start and end of summer when the average daily temperature first exceeds 20 degrees Celsius and then when it falls below 20 degrees Celsius, respectively.

In the 1950s, summer began in mid-June before moving up to early June in the 1980s and 1990s, the agency said. Since 2000, summer has begun to kick off in late May.

Due to the longer summers, winter season has become shorter and started later in the 2000s, compared with 50 years earlier, it also noted.

The agency said global warming is responsible for the recent climate change. The average temperature on the Korean Peninsula rose by 1.2 degrees during the 30-year period since 1981, it said.

Summer may be extended further to last five months at the end of the century, the agency anticipated.

The data came as South Korea is bracing for a longer and hotter summer this year. (Yonhap News)