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Humans Are Causing the Earth To Wobble More Than It Should, NASA Finds (bgr.com)
Iwastheone shares a report from BGR: When looking at the Earth from afar it appears to be a perfect sphere, but that actually isn't the case. Because Earth isn't uniform on all sides due to land masses that shift and change over time, our planet actually wobbles a bit when it spins. Now, a new study by researchers with NASA's Jet Propulsion Laboratory and several universities and science centers has pinpointed the causes of Earth's imperfect spin, called "polar motion," and they found that humans are contributing to it. The researchers used a wealth of data gathered over 100 years to build mathematical models to trace the causes of the wobble and found that three factors are at play, and mankind is responsible for one of them. Two of the three factors identified by the scientists are glacial rebound and mantle convection. Glacial rebound happens when thick ice sheets physically push down on land masses, compressing them, but then release that pressure upon melting. The land then balloons back up over time, causing Earth's spin to wobble as if slightly off-axis. The effects of the last ice age, which would have compressed a huge amount of land across many continents, is still being felt today in the form of glacial rebound.
Mantle convection, the other uncontrollable factor in Earth's wobble, relates to our planet's inner workings. The plates on Earth's surface are in constant flux due to the movement of liquid rock far beneath our feet. The researchers believe these currents also contribute to the planet's imperfect spin. The third and final factor identified by the scientists is the massive loss of ice on Greenland and other areas, which is the direct result of global warming thanks to human activities. The researchers estimate that Greenland has lost roughly 7,500 gigatons, or 7,500,000,000,000 metric tons of ice due to global warming. All that ice loss has happened in the 20th century, and greenhouse gas production has been cited as the primary culprit. Losing all that mass has caused a significant shift on the planet and has contributed to the wobble as well.
Mantle convection, the other uncontrollable factor in Earth's wobble, relates to our planet's inner workings. The plates on Earth's surface are in constant flux due to the movement of liquid rock far beneath our feet. The researchers believe these currents also contribute to the planet's imperfect spin. The third and final factor identified by the scientists is the massive loss of ice on Greenland and other areas, which is the direct result of global warming thanks to human activities. The researchers estimate that Greenland has lost roughly 7,500 gigatons, or 7,500,000,000,000 metric tons of ice due to global warming. All that ice loss has happened in the 20th century, and greenhouse gas production has been cited as the primary culprit. Losing all that mass has caused a significant shift on the planet and has contributed to the wobble as well.
Also the same "scientists" that claim the earth is round!
Global production of concrete is 10 billions per year. Every year, just from concrete production, the earth gets 10 billion tons heavier. And what about the hundreds of millions of cars, trucks and busses that didn't exist a hundred years ago. That's a lot of weight that has been added. And it's not evenly distributed either.
Volcanoes are just pimples, and should be treated Proactivly.
"National Security is the chief cause of national insecurity." - Celine's First Law
They are speaking of 2 different effects, both caused by the melting of ice.
The first effect is due to how the land responds to the ice melting. This continues long after the ice has melted, because the land does not decompress instantly. This is not (really) about glaciers that are melting today, the land is rebounding from glaciers which melted millennia ago.
The second effect is due simply to the loss of the ice itself. As stated in TFS, the 7500Gtons is only over the last 100 years. That much mass loss in a fairly localized area was enough to make a significant contribution to the movement of Earth's center of mass, impacting the wobble.
Finally, it's not the direction so much as the rate. Yes, we're coming out of an ice age, so we would expect average temperatures to gradually climb. However, what we have seen is that the climb has accelerated. Specifically, it has accelerated during the time that we have become industrialized. That acceleration means that certain effects will be more extreme, and we will have less time to adapt or prepare for them.
This is not just true of the climate, but of any non-linear dynamic system (aka everything). When a system moves from one state to another, there are high frequency effects introduced. The faster the system transitions, the more pronounced those effects are.
Only crack the nuts that crack. You don't put the ones that don't crack in the sack.
(OTTMAR EDENHOFER, UN IPCC OFFICIAL): Basically it’s a big mistake to discuss climate policy separately from the major themes of globalization. The climate summit in Cancun at the end of the month is not a climate conference, but one of the largest economic conferences since the Second World War... First of all, developed countries have basically expropriated the atmosphere of the world community. But one must say clearly that we redistribute de facto the world’s wealth by climate policy. Obviously, the owners of coal and oil will not be enthusiastic about this. One has to free oneself from the illusion that international climate policy is environmental policy. This has almost nothing to do with environmental policy anymore, with problems such as deforestation or the ozone hole.
Christine Stewart, former Canadian Environment Minister: “No matter if the science is all phony, there are collateral environmental benefits.... climate change [provides] the greatest chance to bring about justice and equality in the world.”
Monika Kopacz, atmospheric scientist: "It is no secret that a lot of climate-change research is subject to opinion, that climate models sometimes disagree even on the signs of the future changes (e.g. drier vs. wetter future climate). The problem is, only sensational exaggeration makes the kind of story that will get politicians’ — and readers’ — attention. So, yes, climate scientists might exaggerate, but in today’s world, this is the only way to assure any political action and thus more federal financing to reduce the scientific uncertainty."
Researcher Robert Phalen's 2010 testimony to the California Air Resources Board: "It benefits us personally to have the public be afraid, even if these risks are trivial."