Thomas Richard

Climate researchers have published a new paper this week in the journal Nature Climate Change that acknowledges there has been a global warming slowdown from 2000-2014. Their research shows a hiatus did indeed occur and continued into the 21st century, contradicting another study last June that said the hiatus was just an artifact that “vanishes when biases in temperature data are corrected.” This is not the first time activists have tried to hide the hiatus by using dodgy methods.

This new paper shows a global warming slowdown or hiatus, the authors write, which has been “characterized by a reduced rate of global surface warming, has been overstated, lacks sound scientific basis, or is unsupported by observations.” They add, “The evidence presented [in this paper] contradicts these claims.” Ouch.

In this new paper, the authors show there is a “mismatch between what the climate models are producing and what the observations are showing,” says lead author John Fyfe, a climate modeller at the Canadian Center for Climate Modelling and Analysis in Victoria, British Columbia. “We can’t ignore it.” Fyfe prefers the term slowdown over hiatus and adds the usual caveats lest he be taken away from the global warming cash cow: it in no way undermines “global warming theory.”

Gavin Schmidt, a climate activist and a director at NASA’s Goddard Institute for Space Studies, said it’s a “tired discussion and nothing more than academic bickering.” He adds, “A little bit of turf-protecting and self-promotion I think is the most parsimonious explanation. Not that there’s anything wrong with that.”

Snarking aside, this new paper says that natural variability (like volcanic eruptions, solar radiance, ocean heat uptake, etc..) are important elements in evaluating our climate. As such, they should be factored in when trying to interpret the temperature record and the millions of variables that affect our climate.

Karl Thomas, the lead author of the so-called “pause busting” study says it’s ‘important to investigate how short-term effects might impact decadal trends, but says that these short term trends do not necessarily elucidate the long-term effects of rising greenhouse-gas concentrations in the atmosphere.”

Fyfe and his colleagues argue that “Karl’s approach was biased” because of a flat temperature pause between the 1950s and 1970s. Fryfe says that his research took into account events that affect decadal temperature trends such as volcanic eruptions, which dampen solar radiation. As an example, climate models underestimate volcanic eruptions and how they impact how much solar radiation hits the planet, specifically at the start of the 21st century.

Susan Solomon, a climatologist at Massachusetts Institute of Technology (MIT) in Cambridge, says that Fyfe’s research helps put “twenty-first-century trends into perspective, and clearly indicates that the rate of warming slowed down at a time when greenhouse-gas emissions were rising dramatically.” Solomon says, “It’s important to explain that. As scientists, we are curious about every bump and wiggle in that curve.”

The UN’s climate body, the Intergovernmental Panel on Climate Change (IPCC), has already noted that there was a hiatus in global temperatures this century in its last assessment report. As we’ve noted on numerous occasions, the most accurate method for measuring temperatures is the satellite dataset. It shows no warming for 18 years 8 months with 2015 being an unusually warm year due to a naturally occurring El Nino event.

Fyfe’s paper concludes by saying their “results support previous findings of a reduced rate of surface warming over the 2001-2014 period - a period” when emissions like carbon dioxide increased at a steady rate of about two parts per million each year. They point out that the climate models did not predict the warming hiatus that occurred during the first 14 years of the 21st century, even while so-called greenhouse gases have risen. This “mismatch” is a problem that deserves more scientific scrutiny, they add.