The high frequency and magnitude of volcanic eruptions could have been the cause of the progressive cooling of ocean surfaces over a period of 1,800 years. This is made apparent in an international study published recently in the journal Nature Geoscience, involving researcher P. Graham Mortyn of the Institute for Environmental Science and Technology (ICTA-UAB) and the UAB Department of Geography.
The study emphasises that this trend came to an end with the beginning of the Industrial Revolution and the resulting global warming caused by human activity. It further shows that the lowest temperatures in the first 1,800 years of the Common Era were recorded between the 16th and the 18th centuries, a period known as the "Little Ice Age".
Earlier research had already shown that volcanic explosions cause the atmosphere to cool. The present study demonstrates that the oceans can absorb and capture more heat than the atmosphere over longer periods of time, thus attenuating global temperature changes in the short term. These alterations in temperature can be prolonged when the volcanic eruptions are concentrated into a short space of time.
These findings bring a new perspective to the study of regional and global variations in ocean-surface temperature over the centuries, before the appearance of anthropogenic (human activity-induced) climate change.
The researchers combined, for the first time, 57 previous works on sea-surface temperature changes, which are calculated from fossil remains extracted from oceans all over the world, from the Poles to the Tropics. The results were compared with data from terrestrial indicators, such as tree rings or ice cores. These revealed a similar cooling trend.
link.
booyah. called it. Waaaaay back, I wondered if the Little Ice Age was ended by the industrial revolution. The timing was suspicious. I was poopooed back when because folks said the Maunder Minimum was the driving cause of the LIA. It turns that the Maunder Minimum came too late to be the driver and the cooling trends were far, far older. So, with this, we have a little bit more supporting the idea we were headed out of an interglacial and back into another glaciation. Humanity stopped it and may have ended the Quaternary Ice Age altogether. The cost though...
If I ever get around to it, the alternate history I'd dreamed up called the Grinding of Glaciers fit this scenario. (I also have a half finished alt-hist of the Romans in the Americas, Epylium Aurelia).
1 comment:
I'm not so sure the claims of the paper are supported by the data. Take a look at the page 5 of supplementary info which one can get for free here http://www.nature.com/ngeo/journal/v8/n9/extref/ngeo2510-s1.pdf . The proxies are all over the place, both in trend behavior, and in absolute values. But for the most part, they are flat over the period, and there's definitely no uptick in temps within any meaningful margin of error. It really is just an exercise of looking at line wiggles and taking edge effects (the end point of a series always acts weird when binned or averaged) as somehow meaningful. The modern times are certainly not out of the range of behavior in any way here from what I see from the actual data.
This reminds me of a lot of the nutritional/medicinal studies in my field, and how horribly unsupported paper claims and press releases usually are--leading to the constant dueling press releases and mutually exclusive results that just confuse the public due to a lack of careful, skeptical science.
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