[KaiserJeep]

Rising Tides explores the topic of coastline erosion, showing what has been done in the past, what is being done now, what worked, what didn't and what the coastal areas can expect in the future. Through interviews with scientists, experts, nonprofits, homeowners, government officials, and other groups offering possible solutions Rising Tides explores all angles of this threatening issue.

Sorry for the bad news, but there is no distribution other than streaming over the Internet. If you have Amazon Prime membership, it's free.

https://www.amazon.com/Rising-Tides-DR-BENJAMIN-STRAUSS/dp/B01H7QOFKU/ref=sr_1_1?s=instant-video&ie=UTF8&qid=1473037390&sr=1-1&keywords=Rising+Tides

Worth 88 minutes of your time.


I know it's popular to blame AGW for sea level change, but undeniably during a glacial climate phase, vast amounts of water are locked in ice, and things like the Bering Sea land bridge exist. Then the ice melts and the oceans rise. As the OP, I declare this thread is about the facts of SLC, and not about speculation as to the cause. Discussions of AGW and CC are off-topic in this thread.

[rockdoc123]

I think this is a good topic. Sea level is rising even when you look at the tide gauge data (but at a very low rate), as you say to be expected given we are still in an inter-glacial period. So what is the mitigation and where is it necessary? Obviously places like Alaska and some of the west coast of North America aren't a worry in general given they are rising due to tectonic isostasy. The main problem areas to my mind are the SE coastal areas which have natural subsidence due to geologic reasons layered on top of average sea level rise. This is where response needs to be focussed. We saw that during Katrina, much of New Orleans is already in trouble and has been for hundreds of years, it doesn't take much rise to create a problem. Other coastal areas are much less at risk for various reasons.

[KaiserJeep]

The USA has already got land below the present sea level. Everything from New Orleans with several parishes (i.e. counties) about -2m behind the levees, to the Salton Sink in California (a large area that varies from -3m to -70m) to Death Valley which is at -85m.

The MidWest does not vary much in altitude over geological ages. If the sea rises anywhere near the level of the prior inter-glacials, we could (absent the works of mankind) again have a large shallow inland sea over the Great Plains - in say 200 years. Several US states would no longer exist above the water.

Nor is the USA the worst off. Engineers have proposed a massive dam at Gibraltar whose purpose is to preserve the present coastlines of the Mediterranean basin.

[rockdoc123]

The USA has already got land below the present sea level. Everything from New Orleans with several parishes (i.e. counties) about -2m behind the levees, to the Salton Sink in California (a large area that varies from -3m to -70m) to Death Valley which is at -85m.

Realistically looking at current sea level rise rates the coastal area such as NO are in danger but certainly inland areas such as Death Valley are not a worry as long as there is a highland in the way.

[KaiserJeep]

The last inland sea was mostly West of the Mississippi to the Rocky Mountains, much of that area is higher that it was then. The new areas at risk are in the lower Mississippi basin, approximately from mid-Illinois South to the GOM. There is enough rainfall in wet years to make the Northern extremes of that enormous area brackish water versus salty sea water.

To be fair, we are talking about centuries here. Nobody is likely to make plans for that time period.

[GHung]

Maybe we should drill a big tunnel from the Pacific coast to Death Valley; fill it up and buy ourselves a millimeter or two

While we're at it, put some big turbines in that tunnel and harvest tidal energy.

[SeaGypsy]

Would likely change the weather dynamic throughout the region. There has been such discussion regarding salt lakes in southern central Australia, Japan one offered to do the engineering for free, environmental arguments prevented the event. Given likely rainfall increase around the new inland seas, potentially New agriculture areas would be created, new fishing grounds. I'm neither for or against, but interested for sure.

[Subjectivist]

Just watched this. Seems to me it started out pretty strong, but the last half hour was about socializing the costs for all the bad construction choices of the last 30 years and continuing on into the future the same way.

[jedrider]

I don't see how you can separate the topics of AGW and SLR. The latter will accelerate greatly because of the former. How society bears the cost of this is a GOOD question, however. The benefits will, of course, be short-lived precisely because of AGW. (I don't have an Amazon Prime membership, so I'm not going to watch the video).

[KaiserJeep]

I don't see how you can separate the topics of AGW and SLR. The latter will accelerate greatly because of the former. How society bears the cost of this is a GOOD question, however. The benefits will, of course, be short-lived precisely because of AGW. (I don't have an Amazon Prime membership, so I'm not going to watch the video).

It's an entirely pragmatic choice. Whatever the root cause, the facts are we have SLR, and it can't be reversed, slowed, or mitigated. It makes some shallow personalities feel better to place blame on someone else, but that is all wasted effort. Sea levels have been rising and ice shrinking (on the long term average) for 14,000 years.

Even if burning FF's hastened the process, it absolutely will continue until the typical peak temperature of the inter-glacial (the Climatic Optimum) and then ever so gradually it will start to get cold again. That temperature rise is on the order of 6 degrees C and the sea level rise is on the close order of 10 meters.

A real simple choice: do something, or just complain. This thread is about what we can do.

[Tanada]

I don't see how you can separate the topics of AGW and SLR. The latter will accelerate greatly because of the former. How society bears the cost of this is a GOOD question, however. The benefits will, of course, be short-lived precisely because of AGW. (I don't have an Amazon Prime membership, so I'm not going to watch the video).

It's an entirely pragmatic choice. Whatever the root cause, the facts are we have SLR, and it can't be reversed, slowed, or mitigated. It makes some shallow personalities feel better to place blame on someone else, but that is all wasted effort. Sea levels have been rising and ice shrinking (on the long term average) for 14,000 years.

Even if burning FF's hastened the process, it absolutely will continue until the typical peak temperature of the inter-glacial (the Climatic Optimum) and then ever so gradually it will start to get cold again. That temperature rise is on the order of 6 degrees C and the sea level rise is on the close order of 10 meters.

A real simple choice: do something, or just complain. This thread is about what we can do.

Seems to me the choice pragmatically speaking is pretty obvious. Anyone who builds within say 9 feet of sea level is responsible for their losses, not the rest of society. Make that clear and the bulk of dumb building choices would dry up PDQ.

[jedrider]

It's really simple:

Manhattan will become just like a Venice.

Florida will be left to the alligators.

Boston will move inland to higher ground.

Beachfront property will be portable.

[KaiserJeep]

-snip-
Seems to me the choice pragmatically speaking is pretty obvious. Anyone who builds within say 9 feet of sea level is responsible for their losses, not the rest of society. Make that clear and the bulk of dumb building choices would dry up PDQ.

You would think that, wouldn't you? But the World makes political and emotional choices.

Once upon a time, I thought it would be a good idea to invest in a wind farm off Cape Cod, and gave them $7500. Then the Kennedy clan found out that (way way over on the horizon) these windmills would be in sight of this, their 9600 square foot "cottage" in Hyannis, MA.

...and the Kennedys made an unholy alliance with arch-Republican FF magnates, the Koch brothers, who had the contracts for all the coal plants on the Cape, and decades later the wind farm is still unbuilt, and approximately 1200 people per year sicken and many will die from the coal effluents from the 8 massive coal power plants in the area.

It's all about them, and nothing about the taxpayers. We (i.e. US Army Corps of Engineers) already built the concrete "rip-rap" jetty in the above photograph, that reversed the sand erosion occurring on the Kennedy "compound" private beach. In a few decades, we'll pay to save their beach "cottage".

[waterpowerman1]

Something that has been overlooked by our southern facing media is Glacial rebound. Low lying areas and shallow arctic ocean areas that were covered by glaciers in the ice age are rebounding and getting higher. For instance Churchill harbor is rising faster than the ocean. That water has to go somewhere- Florida?. Much of Canada's arctic Islands are rising now without ice cover. This will exaggerate the effect of rising water everywhere else.

[yellowcanoe]

Something that has been overlooked by our southern facing media is Glacial rebound. Low lying areas and shallow arctic ocean areas that were covered by glaciers in the ice age are rebounding and getting higher. For instance Churchill harbor is rising faster than the ocean. That water has to go somewhere- Florida?. Much of Canada's arctic Islands are rising now without ice cover. This will exaggerate the effect of rising water everywhere else.

Glaciation pushes down the land underneath it but it also pushes up land adjacent to a glaciated area. Parts of Nova Scotia were pushed up during the last ice age and are now exhibiting crustal subsidence. Therefore some areas of Nova Scotia would be experiencing a relatively high level of sea level rise even if there was no glacial melting adding to the ocean level.

As KJ points out, glaciers have been shrinking naturally since the end of the last ice age. I certainly believe that man induced climate change has accelerated the melting of glaciers but I don't think anyone can enumerate how much less melting would have occurred without human emissions of green house gases. A good example would be the Athabaska Glacier in Jasper National Park which is fed from the Columbia Ice Field. When the first white explorers and traders entered this area the glacier filled the entire valley and they had to use a trail up the mountains on the east side of the valley to get around the glacier. The glacier had already started to retreat from the valley before any significant amount of carbon dioxide had been added to the atmosphere by human activity. Today the glacier has retreated 1.5km and continues to shrink by around 5m per year.