(Bloomberg) -- It's no longer a question of whether 2016will be the hottest on record, but by how much.

The El Niño warming pattern in the Pacific Ocean is over, butunprecedented heat remains across the planet. Last month was thehottest May in 137 years of record keeping, according to newreports from NASA and the National Oceanic andAtmospheric Administration (NOAA). In an age of risingtemperatures, monthly heat records have become all too common: Maywas the 13th consecutive month to set a new record, according toNOAA data released on Wednesday.

Extremes of recent months

The extremes of recent months are such that we're not even halfwayinto 2016 and there's already a greater than 99% likelihood thatthis year will be the hottest on record, according to Gavin Schmidt, who directs NASA's GoddardInstitute for Space Studies. NASA and NOAA maintain independentrecords of the Earth's temperatures, but they both agree that lastmonth was a scorcher.

If NASA's Schmidt is right, 2016 will be the the thirdconsecutive year to set a new global heat record—the first timethat's ever happened. So far, 15 of the hottest 16 years evermeasured have come in the 21st century. Results from theworld’s chief monitoring agencies vary slightly.The Japan Meteorological Agency said last month was thesecond-hottest May, not the hottest. Nevertheless, all agree thatthe extremes of 2016 are unrivaled in the modern climaterecord.

Planet warming rapidly

Some of this is still the result of last year's monster El Niño,which releases heat into the atmosphere that typically lingers formonths after the underlying conditions subside. Now thatEl Niño has finally come to an end, it may soon shift toa cooling La Niña this summer, according to NOAA's ClimatePrediction Center. The agency gives a 75% chance of a La Niñapattern developing in 2016.

Still, coastal cities are flooding moreregularly, wildfires are starting early, and the world isin the midst of the most prolonged die-off of the ocean'scoral ever witnessed. Beyond the cyclical changes, there's noescaping the larger trend that we live on a planet that'swarming rapidly.

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