Can below sea-level depressions in the earth's surface be used to mitigate the effects of rising sea levels?

Question

There are many inland areas in the world which are below sea level. Death Valley and the Salton Sea Basin in California are examples. Couldn't a siphoning system be designed which would allow these depressions to fill with sea water if melting polar ice leads to rising sea levels? I don't know if there would be enough available volume in these areas to make a real difference, but this is pretty simple technology and i would think that having new inland seas would be preferable to losing Manhattan, wouldn't it? Another example, the Afar Depression in Ethiopia is hundreds of miles long. If the entire East African Rift Valley can be connected to the Red Sea, it could create a sea almost as large as the Red Sea itself...that would have to help, wouldn't it?

Answer 1

Sounds like it could help! (maybe)

Try asking this guy your question: http://www.fondation-nicolas-hulot.org/presentation/mission.php

He is very active on a lot of different levels; he's even been (unofficially) put in charge of the environment by the new French President.

I would be very interrested to see what he thinks of your idea!

Please let me know what response you get (E-mails ok)



And keep thinking that way!!! Well done.



JLB.

Answer 2

Not so long back someone asked a similar question and I did the math at the time - it worked out that approximately 1 trillion cubic metres of 'hole' would be needed each year (the size of a hole 100 kilometres by 100 kilometres by 100 metres deep).



The valleys, depressions, dry lakes and dry sea beds would very soon be filled, there would be other problems as well.



An alternative solution would be to pump the 'excess' sea water onto the Antarctic Plateau, here temperatures are constantly far below freezing. The sea water under pressure in the pipes would remain liquid but would freeze on contact with the Antarctic Ice. In effect we'd be returning the excess water to where it came from in the first place.

Answer 3

That is a very good idea but will help us only in gaining some time. All low land will get water first but those inland may help us to a certain extent. Also this study will let us know which areas are most vulnerable and give us a chance to shift people in the region to safer places.



Global warming is a tricky situation and we donot know what will be the extent of damage, change in land mass and many such questions are still unanswerable. May be we will get some land in Arctic and Antarctic region and ice covered regions will be habitable but how much we will loose?



By this we will be able not only in gaining time but in preparing in a better way, we will know what is happening areas we can use and settle acordingly. Our ancestors shifted in these kind of periods although without scientific knowledge available with us on date but their study of land area was really worth mentioning and they knew very well how and where to move. They had been moving around the whole land mass, communication between civilisations was good and even with limited means they could handle such situations well and this is proved in the Vedas - the great Hindu scripture which probably dates 10000 years minimum.

Answer 4

The pristine nature of the Orinoco Delta of eastern Venezuela provides unique opportunities to study the geologic processes and environments of a major tropical delta. Remote-sensing images, shallow cores, and radiocarbon-dating of organic remains form the basis for describing deltaic environments and interpreting the Holocene history of the delta. The Orinoco Delta can be subdivided into two major sectors. The southeast sector is dominated by the Rio Grande-the principal distributary-and complex networks of anastomosing fluvial and tidal channels. The abundance of siliciclastic deposits suggests that fluvial processes such as overbank flooding strongly influence this part of the delta. In contrast, the northwest sector is represented by few major distributaries, and overbank sedimentation is less widespread relative to the southeast sector. Peat is abundant and occurs in herbaceous and forested swamps that are individually up to 200 km(2) in area. Northwest-directed littoral currents transport large volumes of suspended sediment and produce prominent mudcapes along the northwest coast. Mapping of surface sediments, vegetation, and major landforms identified four principal geomorphic systems within the western delta plain: (1) distributary channels, (2) interdistributary flood basins, (3) fluvial-marine transitional environments, and (4) marine-influenced coastal environments. Coring and radiocarbon dating of deltaic deposits show that the northern delta shoreline has prograded 20-30 km during the late Holocene sea-level highstand. Progradation has been accomplished by a combination of distributary avulsion and mudcape progradation. This style of deltaic progradation differs markedly from other deltas such as the Mississippi where distributary avulsion leads to coastal land loss, rather than shoreline progradation. The key difference is that the Orinoco Delta coastal zone receives prodigious amounts of sediment from northwest-moving littoral currents that transport sediment from as far away as the Amazon system (similar to1600 km). Late Holocene progradation of the delta has decreased delta-plain gradients, increased water levels, and minimized overbank flooding and siliciclastic sedimentation in the northwest sector. These conditions, coupled with large amounts of direct precipitation, have led to widespread peat accumulation in interdistributary basins. Because peat-forming environments cover up to 5000 km(2) of the delta plain, the Orinoco may be an excellent analogue for interpreting ancient deltaic peat deposits.

Answer 5

Inevitably all low land will accommodate some of the rising water (remember New Orleans and Katrina?). If all the ice at the poles melts, we'll see neither the low land nor the high land.

Where will you sit? Do what you can, while you can.

Answer 6

That might work, as long as you don't mind destroying the eco-systems in the areas being flooded. Deserts and rocky areas are not devoid of life. The balance between wet areas and dry ones is one of the things that stabilizes weather patterns. The unintended consequences of following your plan might not be apparent until its too late to avoid them.

Answer 7

It would be extremely expensive to build systems to channel the water there.