# Cry me a River

Discussion in 'Off-Topic' started by MaxHeadRoom, Apr 24, 2016.

Jul 18, 2013
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China's Latest.

2. ### GopherT AAC Fanatic!

Nov 23, 2012
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Wow.

Last edited: Apr 25, 2016
3. ### boatsman Senior Member

Jan 17, 2008
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Fascinating! Thanks Max.

4. ### jpanhalt AAC Fanatic!

Jan 18, 2008
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I wonder about the drop of only 1 cm /45 m when the movement is North, i.e., closer to the axis of rotation of the Earth.

Couldn't find a discussion of that exact subject easily (5-minute search), but I did find this discussion of what would happen to South flowing rivers like the Mississippi should the Earth stop rotating: http://physics.stackexchange.com/questions/209805/rivers-that-flow-uphill-due-to-earths-rotation In brief, they flow up hill relative to gravity, but the rotation keeps them flowing South.

Here are the approximate data I gathered from the video:
Terminus = Beijing (latitude 39°55'N)
Origin = 1200 km South approximate latitude = 29°N
Distance to Earth center at Bejing = 6,369,000 m (https://www.google.com/search?q=mean+seal+level+with+latitude?&newwindow=1&rlz=1C1AVNG_enUS626US626&espv=2&biw=1493&bih=944&tbm=isch&imgil=k2aHzvpJ6PwHHM%3A%3BvpnG_jCiNyx-6M%3Bhttp%253A%252F%252Fwww.summitpost.org%252Fmean-sea-level-distance-vs-latitude%252F850062&source=iu&pf=m&fir=k2aHzvpJ6PwHHM%3A%2CvpnG_jCiNyx-6M%2C_&usg=__Tjz96uWIwyrEQQ8u79cmZta6D28=&ved=0ahUKEwjHnu_U6qnMAhWHuIMKHYZxCAkQyjcIOw&ei=VxMeV4eXBofxjgSG46FI#imgrc=k2aHzvpJ6PwHHM:)
Distance to Earth center at origin = 6,372,500 m (loc. cit. from graph)
Difference in center distance = 3,500 m
Circumference relative to axis at Bejing approx. 30,642 km (assuming a sphere)
Circumference at origin approx. 34,985 km
"Fall" = 1 cm/45 m = 267 m/1200 km (26,667 sections) Relative to what? MSL?

Can anyone here calculate whether that small amount of "fall" and the increased gravity is enough to make this river flow North against the rotational effect? I am assuming the Chinese have done that calculation, but would be interested in seeing the calculation.

John

5. ### GopherT AAC Fanatic!

Nov 23, 2012
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@jpanhalt

The report from BBC is not exactly correct. According to the Atlantic magazine and several others, there will be pumping stations.

from The Atlantic...
The project’s eventual goal is to move 44.8 billion cubic meters of water across the country every year, more than there is in the River Thames. The infrastructure includes some of the longest canals in the world; pipelines that weave underneath riverbeds; a giant aqueduct; and pumping stations powerful enough to fill Olympic-sized pools in minutes. It is the world’s largest water-transfer project, unprecedented both in the volume of water to be transferred and the distance to be traveled​

6. ### jpanhalt AAC Fanatic!

Jan 18, 2008
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Maybe moving that much mass North will increase the rotation velocity of the Earth and for the first time ever, we will have a negative leap second.

Thanks for the more complete information. It is truly a massive project.

John

Jul 18, 2013
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8. ### jpanhalt AAC Fanatic!

Jan 18, 2008
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Earth is already bulged at the equator. The bulge would disappear if Earth stopped rotating. The stackexchange discussion addresses that subject.

John

Jun 26, 2012
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10. ### tom_s Member

Jun 27, 2014
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and if the water goes from south to north, earth does a 180 and usa - the new downunder

11. ### profbuxton Member

Feb 21, 2014
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Oh no, does that mean we have to put up with HC and DT down here?