Huge excitement over an apparent temperature rise of just one tenth of one degree Celsius! plus an argument from ignorance!
As the old saying goes, the absence of evidence is not evidence of absence. But they ignore that. Given their inability to "explain" a tiny fluctuation they say it MUST be due to human activity! They sure are exemplars of scientific rigor! They should go into epidemiology. Speculation passes for fact every day there
It's not research anyway. It's just modelling. Did they include a model where clouds had a cooling effect? I don't need to guess. For your delectation, I append the journal abstract
A US-led research group is claiming to have bolstered the argument that global warming is real, and humans are largely to blame. Scientists say this is the most comprehensive study to date on global ocean warming. The research has been published in the journal Nature Climate Change.
The team looked at rising ocean temperatures over the past 50 years, and a dozen models projecting climate change patterns.
Australian based co-author, Dr John Church from Australia's island state of Tasmania says there's no way all of the world's oceans could've warmed by one tenth of a degree Celsius without human impact. He says nature only accounts for 10 per cent of the increase. [How does he know?]
Dr Church says researchers from America, Australia, Japan and India examined a dozen different models used to project climate change, past studies have only looked at a couple at a time.
"And this has allowed the group to rule out that the changes are related to natural variability in the climate system," he said.
Leading climate change and oceanography expert, Professor Nathan Bindoff says scientists are now certain man-made greenhouse gases are the primary cause. "The evidence is unequivocal for global warming," he said.
He says the new research balances the man-made impacts of warming greenhouse gases and cooling pollution in the troposphere, against natural changes in the ocean's temperature and volcanic eruptions.
"This paper is important because for the first time we can actually say that we're virtually certain that the oceans have warmed, and that warming is caused not by natural processes but by rising greenhouse gases primarily," he said.
The research team says the ground-breaking study will help guide further climate change research and international policy development.
Human-induced global ocean warming on multidecadal timescales
By P. J. Gleckler et al.
Large-scale increases in upper-ocean temperatures are evident in observational records. Several studies have used well-established detection and attribution methods to demonstrate that the observed basin-scale temperature changes are consistent with model responses to anthropogenic forcing and inconsistent with model-based estimates of natural variability. These studies relied on a single observational data set and employed results from only one or two models. Recent identification of systematic instrumental biases in expendable bathythermograph data has led to improved estimates of ocean temperature variability and trends and provide motivation to revisit earlier detection and attribution studies.
We examine the causes of ocean warming using these improved observational estimates, together with results from a large multimodel archive of externally forced and unforced simulations. The time evolution of upper ocean temperature changes in the newer observational estimates is similar to that of the multimodel average of simulations that include the effects of volcanic eruptions.
Our detection and attribution analysis systematically examines the sensitivity of results to a variety of model and data-processing choices. When global mean changes are included, we consistently obtain a positive identification (at the 1% significance level) of an anthropogenic fingerprint in observed upper-ocean temperature changes, thereby substantially strengthening existing detection and attribution evidence.
Nature Climate Change (2012) doi:10.1038/nclimate1553