The report by scientists at the National Oceanic and Atmospheric Administration (NOAA) was published in the journal Science.
It had been thought that temperatures in the 21st century plateaued.
"The new analysis suggests no discernible decrease in the rate of warming between the second half of the 20th century, a period marked by man made warming, and the first fifteen years of the 21st century, a period dubbed a global warming 'hiatus,'" the report said.
With that data, there is no evidence that temperatures in the 21st century have in fact plateaued.
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"Instead, the rate of warming during the first fifteen years of the 21st century is at least as great as that in the last half of the 20th century, suggesting warming is continuing apace," said the study.
Rising temperatures across the planet have set new records, and NOAA has declared 2014 was the hottest year in modern history.
Scientists warn that fossil fuel burning is pushing more greenhouse gas into the atmosphere, leading to increased temperatures, melting of polar ice and glaciers and rising seas.
Experts said the latest study should address some key uncertainties in global warming projections, which are at the heart of major world climate talks in Paris later this year.
"A whole cottage industry has been built by climate skeptics on the false premise that there is currently a hiatus in global warming," said Mark Maslin, professor of climatology at University College London.