Ok, this is one of those “what if” questions that pop up when you stay up late for no real reason other than goofing off. 
If the ocean levels were to rise, what would happen to the amazon?
How much would ocean levels have to rise in order to start flowing up the amazon? Would the amazon basin be affected?
I’m never too worried about ocean-rising paranoia because there is a whole lot of ocean on the earth.
361,800,000 sq km of earth is covered by water…
Lake superior is 12,100 cubic km of water. So if we took lake Superior and dumped it into the ocean, and if I did my math right, the world’s ocean level would raise by 0.00003344389165284688 km…
So…er…3.3cm? It’s quite a bit, but I don’t think it’s anything to panic about.
(I’d encourage anyone to try out my theory and make sure I did the math right)
Lake Superior isn’t the problem. The problems include melting of the ice caps now above sea level, most notably in the Antarctic, and thermal expansion of the oceans. IIRC, the above could raise the level of the oceans by something on the order of 200 feet.
Now would you like to panic? :dubious:
What theory? 
“Melting of the West Antarctica part of the Antarctic ice sheet alone could cause a worldwide sea-level rise of approximately 8 m. The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 73 m.”
Source: http://pubs.usgs.gov/fs/fs50-98/
“Estimated potential maximum sea-level rise from the total melting of present-day glaciers: 80.32 meters”
Source: http://pubs.usgs.gov/fs/fs2-00/
And, you can take that 73 or 80 meters and project it backwards into the mouth of the river and determine where the effect stops.
Exactly - getting back onto the original question, you ain’t gonna see water flowing back uphill. All that will happen is that the mouth of the river will move, because the surrounding land will be submerged. As the Amazon basin is generally fairly low lying, it could move quite a bit.
In fact, the sea level would only have to rise by 48 metres to reach Manaus, which is some 800 miles or so from the present mouth of the river.
What’s the scientific reason that melting ice caps would cause the ocean level to rise? There’s no way it can be just the water from the ice! The net rise would be nothing assuming:
[ul]
[li]The specific gravity of the melted ice and ocean are the same (ice displaces its weight in water, so, melted would occupy the same space)[/li][li]The said ice is actually floating on water. I guess in the case of antarctica, this may not always be the case. But where’s most of this melting ice? On the continent itself, or floating around it? The north pole, not being a land mass, could melt and not increase ocean levels at all.[/li][li]Hi, Opal[/li][/ul]
I was going to mention the same thing concerning the ice “caps”. There is no land at the North Pole to be capped. Here we’re talking icebergs. I’ve encouraged doing this before.
Take a glass and fill it with ice. Fill to rim with water. Let ice melt and see what the water level is. Now explain how melting icebergs are going to raise the ocean levels.
The difference is that the Antarctic icecap is sitting on land - a whole continent - 6.3 million cubic miles / 26 259 545.5 cubic km - whereas the Arctic icecap is free-floating. So if it melts, the water level will rise. Then you have the issue of the glaciers in Canada, Greenland, Scandinavia, and Russia, all of which are sitting on land.
I’m not too worried. The Earth was much warmer 1000 years ago and we’re still here. 2000 years ago, North Africa was the breadbasket of the ancient world.
The Greenland icecap is mostly on land as well It’s small potatoes compared to Antarctica, but it alone melting would cause a small rise.
The answer to the OP, though, is “nothing” – the Amazon’s flow is sufficient that a fair amount of the ocean opposite the mouth is freshwater or brackish (depending on where you are) rather than normal oceanic salinity.
Presumably you don’t own property in a coastal area. The maximum projected sea level rise would eradicate much of Florida, several low-lying island nations, as well as inundate coastal cities from New York and to Calcutta.
Colibri, losing Florida would be bad because…
Try this one instead.
In a bowl, make a stack of ice cubes that extend up over the rim. Fill bowl to the very rim with water. Let ice cubes melt.
Now what happens?
Floridians might move to where you live.
:eek:
Not that it will affect me or anything, but the thought of most of europe and north america ending up like north africa chills me. People of the future may be bummed if all those furtile plains turn into desert.
oh, this has nothing to do with reality, I was just reading about the amazon and one of the other posts running around this board (about icecap melting/ocean rise) at the same time. Got me thinking.
Since I had heard that the amazon basin is pretty low lying I just wondered what sort of ecological effect it would have.
In other words how much of the basin would it affect, when you consider that depending on how much it rises it would affect the worlds largest tropical forest (increase salinity, killing trees, etc).
That sort of thing.
robby wrote:
"Now would you like to panic? "
I’ve got all my emotional difficulties planned for this week. Maybe I can fit a panic in next Friday, but only for 20 minutes.
The changes in climate 800 years ago affected primitive peoples quite significantly worldwide. Whole tribes got wiped out or displaced by a fairly small change.
Now start multiplying effects. Bigger changes taking place in less time. Think in terms of nations of 100s of millions of people. Wiping out/displacing that many people is an immensely bigger issue. This “there have been climate changes in the past so don’t worry about it” is such an astonishingly ill-conceived statement that I just can’t understand why people say it. It’s like someone saying “we’ve had world wars before, so don’t worry if we have another one.” Umm, world wars were horrible before nukes, with nukes it’s orders of magnitude more horrible. Bad things that happened before under conditions not a dire as today can’t possibly be consoling information.
Again, addressing the OP: The low lying areas of Brazil will be under the ocean. This includes areas currently surrounding the mouth of the Amazon. The new mouth of the Amazon will be many, many miles inland from where it is now.
While the current melting is taking place in the blink of an eye by geological time-scale standards, it won’t be fast enough to cause water to visibly rush overland anywhere (on average). Each high tide with storm surge will reach further and further inland and not completely recede to the former shore.