Why Man-Made Earthquakes (If They Exist) Are Less Intense, Of Less Concern Than Natural Earthquakes (Perhaps Even Of Benefit) -- August 21, 2014

I thought I had posted this before; can't find the original article. A reader sent me a link explaining why man-made earthquakes (if they exist) are less intense than natural earthquakes.

Expanded oil and gas operations in the central and eastern United States have triggered earthquakes as large as magnitude 5.7, as drillers inject wastewater back into the ground. But seismologists now report a bit of good news: such 'induced' quakes appear to shake the ground less than a naturally occurring earthquake of the same magnitude would.

That is good news because less shaking means less damage. “Maybe induced earthquakes aren’t quite as fearsome as they may seem,” says Susan Hough, a seismologist at the US Geological Survey (USGS) in Pasadena, California, whose work is published in the Bulletin of the Seismological Society of America.

“The hazard from induced quakes is going to be down a notch relative to tectonic quakes.”

But the observation holds only for areas more than 10 kilometres from the earthquake’s epicentre. Anyone close to the drilling would still feel as much shaking as a natural quake would bring. “This might lead to a recommendation that deep injection wells should be kept 10 kilometres away from population centres,” says Hough.

And ten kilometres from the New York State border. No doubt.

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Explanation For Global Warming Pause?

Science via Live Science is reporting:

In 1999, the feverish rise in Earth's surface temperatures suddenly slowed, even as greenhouse gas emissions escalated. This unexpected slowdown has been called a global warming hiatus or global warming pause. Most climate scientists don't think this hiatus means global warming went kaput, but the reason (or reasons) for the slowdown has scientists flummoxed. Researchers have offered more than two dozen ideas to explain the missing heat.

Now, a study published today (Aug. 21) in the journal Science suggests a natural climate cycle in the North Atlantic Ocean gobbled Earth's extra heat. While the study is unlikely to settle the scientific debate, it does support the idea that Earth's global warming continues in the ocean, even when air temperatures stay flat.

I'm going to have to put thermometers in the ocean now, along with my popsicle sticks with millimeter hash marks. Does this mean the oceans are still rising? Warm oceans, and yet sea ice is expanding, setting new records in the Antarctic? Hard for all this to be reconciled. If nothing else, a new avenue for research grants. I think a good spot to do this research is off the big island of Hawaii. Just saying.