Global warming paused / stopped
The claimed 'pause' from 1998 to 2012 was a result of starting from an unusually warm El Nino year. NOAA and Stanford analyses found no statistically significant slowdown when proper baselines are used. Ocean heat content, sea levels, and ice loss continued to rise throughout the period.
What we know
The 'pause' or 'hiatus' claim emerged from comparing surface temperature trends from 1998 to 2012 against longer-term trends. The problem is that 1998 was one of the strongest El Nino years on record, producing a temporary surface temperature spike that made subsequent years look flat by comparison. Starting a trend line from a statistical outlier is a well-known way to mislead.
A 2015 paper in Science led by NOAA's Thomas Karl updated ocean temperature measurements and found no evidence of a hiatus. A separate 2015 Stanford study by Rajaratnam and colleagues used a statistical framework designed for geophysical data and concluded: 'Our results clearly show that in terms of the statistics of the long-term global temperature data, there never was a hiatus, a pause or a slowdown in global warming.' NOAA's own FAQ acknowledges that from 1998 to 2012 the rate of surface warming was slower, but explains this through natural variability, volcanic aerosols, and low solar activity, while noting that the underlying warming trend continued in ocean heat content, sea level rise, and Arctic ice loss.
Subsequent data have rendered the debate moot: 2014, 2015, 2016, 2019, 2020, 2021, 2022, 2023, and 2024 all broke or tied temperature records. The five warmest years in the instrumental record all occurred after 2015.
Common claims
- Global warming stopped after 1998False - caused by cherry-picking 1998 El Nino; subsequent years broke records
- The rate of surface warming slowed from 1998 to 2012Partially true but misleading - ocean warming, sea level, and ice loss continued unabated
- Scientists now admit there was a warming pauseFalse - updated analysis found no statistically significant pause