Here is how it was done:
"Sea temperature data, some collected by a fleet of drifting and diving probes, shows that a decade-long slowdown in global surface warming masked a coincident rise in ocean temperature below 300 feet, according to NASA JPL researchers.
That finding, which was published recently in the journal Science, is the latest paper to take on the controversial topic of the global warming pause, or hiatus. Last month, researchers at the National Oceanographic and Atmospheric Administration argued that the slowdown never occurred. In the JPL study, climate scientists Veronica Nieves, Josh Willis and William Patzert pored over sea temperature data dating back two decades.
A large portion of this information was collected by the Argo array -- a network of more than 3,000 automated sea probes that can dive deeper than a mile, take temperature and salinity readings, then return to the surface where they transmit the information to orbiting satellites.
"They're the oceans' weather balloons," Willis said of the devices.
What researchers discovered was that during the period of the hiatus -- from roughly 2003 to 2013 -- sea surface temperatures in the Pacific and Indian oceans rose more slowly than they had in previous years.
However, heat was actually accumulating in a layer of water just below the surface, in an area between 300 and 1,000 feet deep. This layer of warming showed that even though the rise in global average surface temperature had slowed, the ocean continued to absorb heat generated by greenhouse gasses, authors said.
"Basically what happened is the heat missing from the surface went to a subsurface layer in the Pacific and Indian oceans," said Nieves, the lead study author. The precise mechanism by which the oceans trapped heat in this middle layer of water remains unclear, but researchers say it occurs on a decadal timescale. Patzert said that this subsurface heating gradually "piled up" in the western Pacific Ocean, then "leaked" into the Indian Ocean. The idea that the Pacific Ocean absorbed heat that would have otherwise led to a rise in global average surface temperature is not new. However, the JPL study is the first to use only direct observations to describe the phenomenon and specify a precise area of warming.
Lead author Nieves said that previous studies have relied on model-based data, or a combination of models and observations, to frame their conclusions.
"This can lead to completely different results," Nieves said."
And some more:
"Karl said the new data were the result of some recent revelations on the part of climatologists.
Although researchers have long known that sea surface temperatures measured by autonomous buoys run cooler than temperatures measured by ships, they have failed to account for this as they expanded their use of buoy readings over the last two decades, the study authors argued.
This, combined with the fact that ships now sample a smaller area of the world's oceans, have skewed the data toward cooler temperatures, they say.
Also, though it had long been assumed that ships measured seawater temperature with engine intake thermometers — an innovation that began after World War II — that is not the case, Karl said. Instead, some ships still scoop up seawater in canvas or metal buckets.
“The buckets, when you pull them up, tend to evaporate their water, and if they're canvas there's even more evaporation,” Karl said. “By the time people stick a thermistor in the bucket to measure temperature, it's already slightly cool.”
To correct for the discrepancy between bucket and engine measurements, Karl and his colleagues used nighttime air temperature readings taken from the deck of the ship to calibrate the readings."
"Science" has the most rigorous refereeeing policy of just about any scientific journal
If you have a problem with the methodology you should submit a rebuttal to the journal
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