Would it surprise you to learn the greatest global two-year cooling event of the last century just occurred? From February 2016 to February 2018 (the latest month available) global average temperatures dropped 0.56°C. You have to go back to 1982-84 for the next biggest two-year drop, 0.47°C—also during the global warming era. All the data in this essay come from GISTEMP Team, 2018: GISS Surface Temperature Analysis (GISTEMP). NASA Goddard Institute for Space Studies (dataset accessed 2018-04-11 at https://data.giss.nasa.gov/gistemp/). This is the standard source used in most journalistic reporting of global average temperatures.
The 2016-18 Big Chill was composed of two Little Chills, the biggest five month drop ever (February to June 2016) and the fourth biggest (February to June 2017). A similar event from February to June 2018 would bring global average temperatures below the 1980s average. February 2018 was colder than February 1998. If someone is tempted to argue that the reason for recent record cooling periods is that global temperatures are getting more volatile, it's not true. The volatility of monthly global average temperatures since 2000 is only two-thirds what it was from 1880 to 1999.