Environment

2017 Crushed a Major Temperature Record and Scientists are Sounding the Alarm

January 5, 2018

It’s been very cold over North America for days, but globally,Ā 2017 has ended up smashing the record for the hottest year on record without an El NiƱo.

And that has scientists worried, since the warmest years usually happen when the long-term human-caused global warming trend gets a short-term boost from anĀ El NiƱo’s enhanced warmingĀ in the tropical Pacific.

The fact is that without global warming, ā€œall the natural influences should have made the year cooler than normal; not hotter than normal,ā€Ā professor of thermal sciencesĀ John AbrahamĀ explained to ThinkProgress.

Climatologist Michael Mann said in an email that the recent spate of annual temperature records means that not only hasn’t global warming warming slowed down, as the deniers have asserted, ā€œIf anything, it’s accelerating as we continue to pump carbon into the atmosphereĀ through the burning of fossil fuels.ā€

The chart below shows El NiƱos are generally the hottest years on recordā€Š whereas La NiƱa years, withĀ their cooler-than-normal temperatures in the tropical Pacific,Ā are usuallyĀ belowĀ the global warming trend line.

1964–2017 global surface temperature data from NASA, divided into El NiƱo (red), La NiƱa (blue), and neutral (black) years, with linear trends added. CREDIT: Dana Nuccitelli
1964–2017 GLOBAL SURFACE TEMPERATURE DATA FROM NASA, DIVIDED INTO EL NIƑO (RED), LA NIƑA (BLUE), AND NEUTRAL (BLACK) YEARS, WITH LINEAR TRENDS ADDED. CREDIT: DANA NUCCITELLI

Environmental scientist Dana Nuccitelli explained in theĀ UK GuardianĀ Tuesday, ā€œFor each type of year — La NiƱa, El NiƱo, and neutral — the global surface warming trend between 1964 and 2017 is 0.17–0.18°C per decade, which isĀ consistent with climate model predictions.ā€

What’s so remarkable about 2017, Nuccitelli notes, is that it crushed the old record for hottest non-El NiƱo year (2014) by ā€œa whopping 0.17°C.ā€ In fact, 2017 was so hot, it’s the second hottest year on record, surpassing evenĀ 2015, which had a strong El NiƱo.

ā€œThe fact we continue to see records break regardless of the natural conditions means that we humans have over-ridden the natural cycle,ā€ Abraham points out. ā€œOnce again, the real data creates liars of those who deny climate change, like Trump.ā€

Joe Romm

Dr. Joe Romm is Founding Editor of Climate Progress, ā€œthe indispensable blog,ā€ as NY Times columnist Tom Friedman describes it.


Tags: El NiƱo, global temperatures, global warming