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Deep Pacific Waters Are Cooling Down Due To Centuries-Ago Little Ice Age, New Study Suggests (inquisitr.com)
schwit1 quotes a report from The Inquisitr: Most of the world's waters may be warming as a result of climate change, but a new study shows that the deepest parts of the Pacific Ocean still appear to be cooling down hundreds of years after the period in history known as the "Little Ice Age." According to a report from Science Daily, a team of researchers from the Woods Hole Oceanographic Institute (WHOI) and Harvard University discovered that there has been a "lag" of a few centuries in terms of temperature change in the deep Pacific. This part of the ocean, the report stressed, is still seemingly cooling and adjusting to the temperature drops of the Little Ice Age while the rest of the Pacific gets warmer as a result of modern factors.
"These waters are so old and haven't been near the surface in so long, they still 'remember' what was going on hundreds of years ago when Europe experienced some of its coldest winters in history," commented WHOI physical oceanographer Jake Gebbie, lead author of the new study. As documented in a paper that was published Friday in the journal Science, the researchers created a model simulating how the deep Pacific's temperature might react to changes in climate on the surface, then compared the data from the model against two historical sources. These sources included ocean temperature data taken in the 1870s by scientists aboard the HMS Challenger and temperatures gathered over a century later, through the World Ocean Circulation Experiment in the 1990s. Based on how these comparisons aligned, the researchers found that warming was present in most parts of the world's oceans and consistent with the current trend of climate change. The only exception was the deep Pacific, where temperatures were cooling at around 1.25 miles (two kilometers) deep. This suggested that long-ago changes in surface climate, such as those that took place during the Little Ice Age, could still have an influence on the effect of climate change in modern times.
"These waters are so old and haven't been near the surface in so long, they still 'remember' what was going on hundreds of years ago when Europe experienced some of its coldest winters in history," commented WHOI physical oceanographer Jake Gebbie, lead author of the new study. As documented in a paper that was published Friday in the journal Science, the researchers created a model simulating how the deep Pacific's temperature might react to changes in climate on the surface, then compared the data from the model against two historical sources. These sources included ocean temperature data taken in the 1870s by scientists aboard the HMS Challenger and temperatures gathered over a century later, through the World Ocean Circulation Experiment in the 1990s. Based on how these comparisons aligned, the researchers found that warming was present in most parts of the world's oceans and consistent with the current trend of climate change. The only exception was the deep Pacific, where temperatures were cooling at around 1.25 miles (two kilometers) deep. This suggested that long-ago changes in surface climate, such as those that took place during the Little Ice Age, could still have an influence on the effect of climate change in modern times.
During the Little Ice Age, surface temperatures in the Southern Hemisphere dropped by about 2C, and sea ice expanded while snowfall decreased. The coldest and densest water in the ocean is Antarctic bottom water, which forms as ice freezes on the surface. The ice is nearly salt free, which means the seawater left behind is extra salty, and thus dense, so it sinks. When it reaches the bottom, it can't just immediately flow toward the deepest part of the sea, because there is no monotonic slope. Instead it fills basins close to the ice shelf, and only flows to deeper water when those are full. Yes, this can take centuries. Reason: The ocean is big. Really big.
Here is an excellent description of the topology of the ocean bottom. Especially look at the last map, showing the deep basins around Antarctica.
This is the worst pseudo-science since Trump shut down the EPA for generating most of it.
An this the exact kind of crap that you keep saying about any study that doesn't agree with your views on what should be. If a study doesn't support your ridged views on climate change is fake science or pseudo science. It has gotten so bad that you throw this label at a study, such at this one, that doesn't in any way refute man made climate change in any way.
All this study shows is that an event that happened hundreds years ago can still have an effect on the climate today. That just goes to show how complex the climate is and how much we actually don't know about it. This study in no way refutes any affect that man made effect will have on the climate.
I read at +2. If your post doesn't reach that level I will not see or respond to it.
There is no type of proof that cannot be warped into the Global Warming Armageddon myth.
"Proof" is a mathematical concept. In science, there is only evidence.
The evidence is that the very deepest ocean water, in the Marianas, Philippine, and Bougainville trenches, is getting colder. A plausible hypothesis is the one made in TFA: A lag of Antarctic bottom water from the Little Ice Age, because of the deep basins in the Southern Ocean.
This is supported by models, and (most importantly) is falsifiable: If the hypothesis is correct, the water in the southern basins should be getting warmer. Surface waters should also be warming. Only the extreme depths should be getting colder.
If you have an alternative hypothesis, then please tell us, and explain how it can be falsified.
Other "contradictory" evidence, such as expanding sea ice around Antarctica, is also best explained within the context of global warming: As air temperatures rise, they hold more moisture, which means more snowfall onto the ice pack. So the ice pack is expanding even as measured air temperatures rise. Notably, this is NOT happening in the Arctic, since temperatures there are already higher. The northern ice pack has shrunk by over a million square miles. Feel free to post an alternative falsifiable hypothesis.
If the water is cooling then ...
The water is NOT cooling. Warmer water is being displaced by colder/saltier/denser water flowing in from further south.
This is called thermohaline circulation, and it is a well know phenomena.