Posted on 05/11/2016 12:34:28 AM PDT by blueplum
Full title: Ancient bubbles in Australian rocks show early Earth's air weighed less than half today's atmosphere
Air bubbles trapped in 2.7 billion-year-old Australian rock suggest the Earth's atmosphere weighed less than half of today and was much thinner than previously thought.
Researchers analysed the size of air bubbles that formed at the top and bottom of lava flows along the Beasley River in Western Australia's Pilbara region almost three billion years ago and used the data to calculate the atmospheric pressure at the time. The results suggest that the air at the time exerted at most half the pressure of today's atmosphere.
The findings, published on Monday in Nature Geoscience, reverse the commonly accepted idea that the early Earth had a thicker atmosphere to compensate for sunlight being about one fifth weaker than now. {snip} The result also reinforces Prof Buick’s 2015 finding that microbes were pulling nitrogen out of Earth’s atmosphere some three billion years ago.
“The levels of nitrogen gas have varied through Earth’s history, at least in Earth’s early history, in ways that people just haven’t even thought of before,” said co-author David Catling, a University of Washington professor of Earth and space sciences. “People will need to rewrite the textbooks.”
(Excerpt) Read more at telegraph.co.uk ...
Oh thanks!
no pics or it didn’t happen ;-)
I was wondering how they knew the temp of the rock wasn’t hotter or cooler than more recent magma flows.
More settled science...
So is the Earth losing 50,000 tonnes per year of atmosphere?
That only works within a fixed volume (V). With an undefined volume, all we know is that P at sea level is about 15 psi. That means there is a total of about 15 pounds of air above every square inch of surface. It’s gravity that’s holding it there, not a volume constraint.
Are those estimates as accurate as those which are used in computer models that "prove" anthropogenic global warming? < /sarc >
Carbon taxes should be retroactive over the 2.7 billion year life of the ancient air bubbles. At a buck a day, that is $2.7 billion. Heck, I could live well on that. AL Gore, eat my shorts.
One of the remaining big unknowns would be the effect of the rock on the gas over billions of years, especially given the fact that the rock has probably been compressed and heated repeatedly.
There's a similar issue with CO2 samples from gas bubbles in ice cores, since CO2 readily dissolves in water.
“Just out of curiosity, do you have a reference for that?”
Earth Loses 50,000 Tonnes of Mass Every Year
February 5, 2012
According to some calculations, the Earth is losing 50,000 tonnes of mass every single year, even though an extra 40,000 tonnes of space dust converge onto the Earth’s gravity well, it’s still losing weight.
[....]
http://scitechdaily.com/earth-loses-50000-tonnes-of-mass-every-year/
Getting a Handle on How Much Cosmic Dust Hits Earth
Does Earth have a dust build-up problem?
Estimates vary of how much cosmic dust and meteorites enter Earth’s atmosphere each day, but range anywhere from 5 to 300 metric tons, with estimates made from satellite data and extrapolations of meteorite falls. Thing is, no one really knows for sure and so far there hasn’t been any real coordinated efforts to find out. But a new project proposal called Cosmic Dust in the Terrestrial Atmosphere (CODITA) would provide more accurate estimates of how much material hits Earth, as well as how it might affect the atmosphere.
“We have a conundrum – estimates of how much dust comes in vary by a factor of a hundred,” said John Plane from University of Leeds in the UK. “The aim of CODITA is to resolve this huge discrepancy.”
[....]
http://www.universetoday.com/94392/getting-a-handle-on-how-much-cosmic-dust-hits-earth/
Mass accumulation of Earth from interplanetary dust, meteoroids, asteroids and comets
Sandra Drolshagen1, Jana Kretschmer1, Detlef Koschny2,3, Gerhard Drolshagen2, Björn Poppe1
1 Universitätssternwarte Oldenburg, Carl von Ossietzky University of Oldenburg, Ammerländer Heerstr. 114-118, D-26129 Oldenburg, Germany
sandra.drolshagen@uni-oldenburg.de
2 European Space Agency, ESA/ESTEC, Keplerlaan 1, NL-22001 AZ Noordwijk, The Netherlands
3 Chair of Astronautics, TU Munich, Boltzmannstr. 17, D-85748 Garching, Germany
The goal of this paper is to determine the mass that reaches the Earth as interplanetary material. For the large objects the flux model by Brown et al. (2002) was used which is valid for bodies greater than 1 m and is based on sensor data of fireballs that entered the Earth atmosphere. For the small sizes the flux model by Grün et al. (1985) was used, which describes the mass flux at 1 AU for meteoroids in the mass range 10-18 g to about 100 g. The Grün flux was converted to 100 km height by taking the Earth attraction into account and all units were adjusted to compare the model with the one by Brown. In a second step both models were combined by an interpolation, which lead to a flux model that covers 37 orders of magnitude in mass. Using recent measurements and alternative flux models the uncertainties of the obtained model was estimated. Recent measurements include in-situ impact data on retrieved space hardware and optical meteor data. Alternative flux models are e.g. a NASA model for large sizes that is an extrapolation of known Near-Earth Objects (NEOs) and a model by Halliday et al. (1996) which is based on optical measurements of fireballs. Up to a diameter of 1 km the total calculated mass influx is 54 tons per day.
[....]
http://www.imo.net/imc2015/2015-24-drolshagensandra-final.pdf
Perhaps actual measurement of a plasma plume from atmospheric gas blown away by solar wind?
“So is the Earth losing 50,000 tonnes per year of atmosphere?”
That is only an estimate for the amount of atmospheric mass being lost to space. The amount of atmospheric mass being lost and gained in exchanges of mass between the atmosphere, hydrosphere, cryosphere, biosphere, and lithosphere are highly variable over geological time periods. As the Sun grows larger as it enters the Red Giant phase of its life cycle, the Earth will be stripped of all but a trace remnant of its atmosphere and hydrosphere by the strong Solar Winds. Then the Earth’s lithosphere will begin to vaporize.
“no pics or it didn’t happen ;-)”
Will a photograph of George Washington suffice?
We need more taxes to stop the loss of loss of 50,000 tonnes per year!
I do as well. We also know that carbon dioxide is 1.4 times as heavy as oxygen of a similar volume. The atmosphere in the pre-deluvian times was much lighter and more oxygen rich, permitting much greater growth of plant and animal life. It also permitted more rapid movement. It also permitted extraordinary creatures to survive when today we know their lung capacity could not sustain them. That, combined with the water vapor filtering out so the ultra violet rays, and people lived extraordinarily long lifespans as told in the Bible.
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