Essay by Eric Worrall
The oceans swallowed my global warming? Desperate butt covering from alarmists who are facing increasingly embarrassing questions about the failure of the world to end.
14 July 2022 16:41
Factcheck: No, global warming has not ‘paused’ over the past eight years
A decade ago, many in the climate community were fixated on an apparent “pause” in rising global surface temperatures. So many studies were published on the so-called “hiatus” that scientists jokedthat the journal Nature Climate Change should be renamed Nature Hiatus.
However, after a decade or so of slower-than-average warming, rapid temperature rise returned in 2015-16 and global temperatures have since remained quite warm. The last eight years are the warmest eight years since records began in the mid-1800s.
While the hiatus debate generated a lot of useful research on short-term temperature variability, it is clear now that it was a small variation on a relentlessly upward trend in temperatures.
But nearly a decade later, talk of a “pause” has re-emerged among climate sceptics, with columnist Melanie Phillips claiming in the Times this week that, “contrary to the dogma which holds that a rise in carbon dioxide inescapably heats up the atmosphere, global temperature has embarrassingly flatlined for more than seven years even as CO2 levels have risen”.
This falsehood appears to be sourced from a blog post by long-time climate sceptic Christopher Monckton, which claims to highlight the lack of a trend in global temperatures over the past eight years.
In a rebuttal letter to the Times, Prof Richard Betts – head of climate impacts research at the Met Office Hadley Centre and University of Exeter – points out that it is “fully expected that there will be peaks of particularly high temperatures followed by a few less hot years before the next new record year”.
In fact, the last eight years have been unusually warm – even warmer than expected given the long-term rate of temperature increases – with global temperatures exceeding 1.2C above pre-industrial levels. The temperature record is replete with short-term periods of slower or more rapid warming than average, driven by natural variability on top of the warming from human emissions of CO2 and other greenhouse gases.
There is no evidence that the past eight years were in any way unusual and the hype around – and obvious end of – the prior “pause” should provide a cautionary tale about overinterpreting year-to-year variability today.
Human-emitted greenhouse gases trap extra heat in the atmosphere. While some of this heat warms the Earth’s surface, the vast majority – around of 93% – goes into the oceans. Only 1% or so accumulates in the atmosphere and the remainder ends up warming the land and melting ice.
Most years set a new record for ocean heat content, reflecting the continued trapping of heat by greenhouse gases in the atmosphere. The figure below shows that annual OHC estimates between 1950 and present for both the upper 700m (light blue) and 700m-2000m (dark blue) depths of the ocean.
Lord Moncton apparently stirred the hive by publishing a few articles on the growing pause, like this article from three weeks ago.
His article on the last 6 years are entertaining because, where’s the warming? Wasn’t there supposed to be a hockey stick or something? Oh yeah, it disappeared into the ocean depths, allegedly.
The last 172 years, since 1850, temperatures have risen a little. Except for that period between the 1940s to 1970s, when the drop in global temperature triggered climate scientists like Stephen Schneider to suggest we should use nuclear reactors to melt the polar ice, to prevent an ice age. Schneider later claimed he’d made a mistake, and went on to become a global warming activist.
But that context doesn’t stop in 1850.
Looking before 1850, there were notable warm periods during the last few thousand years, like the medieval warm period, Roman Warm Period and Minoan Warm Period, which look suspiciously like our current modern warm period, except back then people didn’t drive automobiles.
20,000 years ago, much of the world was covered by massive ice sheets.
Three million years ago, the world was so warm Antarctica was mostly ice free – until the onset of the Quaternary glaciation, which we are still enduring today. To put the Quaternary Glaciation into context, the Quaternary is one of only five comparable great cold periods which have been identified over the last two billion years.
55 million years ago was the Palaeocene – Eocene thermal maximum, an extremely warm period of such abundance our primate ancestors spread throughout much of the world.
When you take a more complete look at the context, rather than the limited 172 year / 0.0000086% of climate history Carbon Brief seems to want you to focus on, there is nothing unusually warm about today’s global temperatures. Even if further global warming does occur, if those little primate ancestors with walnut size brains could manage to thrive in the Palaeocene – Eocene thermal maximum, I’m pretty sure we could figure out how to cope with a small fraction of the warming they enjoyed.