An elephant plays water at a zoo during heat wave in southern Pakistani port city Karachi, on Oct. 12, 2017. (Xinhua/Arshad)

WASHINGTON, Oct. 18 (Xinhua) -- The year 2017 is gearing up to end up among the top three warmest years in 137 years of record-keeping, U.S. National Oceanic and Atmospheric Administration (NOAA) said on Wednesday.

In a monthly report, the U.S. agency said the year-to-date temperature across global land and ocean surfaces was 0.87 degrees Celsius above the 20th century average of 14.1 degrees Celsius.

"This was the second highest value for January-September in the 1880-2017 record, behind the record year of 2016 by 0.13 degrees Celsius," it said.

A Pakistani boy cools himself off in a water canal as the temperature reached 42 degree Celsius in southern Pakistani port of Karachi on Oct. 13, 2017. (Xinhua/Arshad)

Nine of the 10 warmest January-September global land and ocean temperatures occurred since 2005. The only one exception was in 1998.

Based on the data, "2017 will likely end up among the top three warmest years on record," it concluded.

In addition, September was the fourth warmest such month on record, the NOAA said.