Here's a statistic: On Earth, 18 of the last 19 years have been the warmest in recorded history.
And as both NASA and the National Oceanic and Atmospheric Administration (NOAA) announced on Wednesday, the last five years have been the five hottest in history — since quality record-keeping began in the 1880s. It's an unmistakable, accelerating warming trend.
The globe's 21st-century heating, however, becomes all the more stark when compared to the coldest years on record. As climate scientist Simon Donner, who researches human-induced climate change at The University of British Columbia, underscored via a list posted on Twitter, the planet's 20 coldest years all occurred nearly a century ago, between 1884 and 1929.
The coldest year on record occurred in 1904.
Coldest years in recorded (since 1880) history:
— Simon Donner (@simondonner) February 9, 2019
Earth's average temperature has risen by over 1.8 degrees Fahrenheit (1 degree Celsius) since the onset of the industrial revolution, making yearly cold records increasingly rare.
But it's not just annual cold records that are becoming rarer. In the last 10 years, twice as many daily heat records have been set as cold records.
The score is 21,461 record daily highs to 11,466 record lows.
"In fact, we are seeing an increase in daily heat records, and we are NOT seeing an increase in daily cold records," Michael Mann, a climate scientist at Penn State University told Mashable last week.
"The trend is in exactly the direction we would expect as a result of a warming planet," Mann said.
Although potent heat-trapping greenhouse gases — notably carbon dioxide — have been warming the planet for well over century, in the last 40 years the trend has accelerated, and grown notably pronounced.
"We've known since the 1980s that Earth has had a fever," Sarah Green, an environmental chemist, explained to Mashable earlier this year.
100 years of January sea surface temperature (SST) anomalies (departure from average). Note the long-term warming and patterns of climate variability (e.g., El Niño/La Niña).
[Data from ERSSTv5 at https://t.co/voKbaxl8Zi] pic.twitter.com/yvRXSBGS61
— Zack Labe (@ZLabe) February 7, 2019
This is a consequence of simple physics, understood since the 19th century. Back in the late 1880s, there were simply far lower levels of carbon dioxide in the air. Now, carbon dioxide levels are likely the highest they've been in some 15 million years.
And the Earth is responding. Earth is warmer than it's been in some 120,000 years — back when hippos roamed Europe.
So cold records, as expected, are dying out.