An article in Monday’s Guardian (UK) would seem to vindicate those of us in the climate skeptic (sceptic?) community who have suspected that computer models of climate processes were overly focused on the warming influence of carbon dioxide. As it turns out, the climate is a complex system, susceptible to influence from volcanoes, oceans, variable solar output, soot, etc., just as we have been saying all along. Um, it’s not as if volcanoes have only been erupting these last 17 years, guys.
The “climate community”, undeterred, doubles down.
“This is a complex detective story,” said Benjamin Santer of the Lawrence Livermore National Laboratory in California, lead author of the study in the journal Nature Geoscience that gives the most detailed account yet of the cooling impact of volcanoes.
“Volcanoes are part of the answer but there’s no factor that is solely responsible for the hiatus,” he told Reuters of the study by a team of US and Canadian experts.
Volcanoes are a wild card for climate change – they cannot be predicted and big eruptions, most recently of Mount Pinatubo in the Philippines in 1991, can dim global sunshine for years.
Santer said other factors such as a decline in the sun’s output, linked to a natural cycle of sunspots, or rising Chinese emissions of sun-blocking pollution could also help explain the recent slowdown in warming.
The study suggested that volcanoes accounted for up to 15% of the difference between predicted and observed warming this century. All things being equal, temperatures should rise because greenhouse gas emissions have hit repeated highs.
No word on whether the New York Times wants to stab Santer in the heart.
Despite the inescapable conclusion that the climate modelers were wrong, the article explains:
Explaining the hiatus could bolster support for a UN climate deal, due to be agreed by almost 200 governments at a summit in Paris in late 2015 to avert ever more floods, droughts, heatwaves and rising sea levels.
The article abstract is here. The article itself is available for a fee, but the first two sentences of the abstract are noteworthy:
Despite continued growth in atmospheric levels of greenhouse gases, global mean surface and tropospheric temperatures have shown slower warming since 1998 than previously. Possible explanations for the slow-down include internal climate variability, external cooling influences and observational errors.
You don’t say.
More at wattsupwiththat.com.
Cross-posted at the defunct stevemaley.com.