[jessriedel]

Becoming an adult doesn't give you the power to do a cost-benefit analysis for a continent-wide megascale project in your head. You can reject this proposal out of hand for rights-based reasons, but you have no idea whether the costs outweigh the benefits.

[TadaScientist]

Ouch!

Unsurprisingly I agree with your first sentence. But, I do disagree on your second: I, and others, can see the costs, and I am not referring solely to the financial costs:

It absolutely means risk of war in the Balkans, Greece/Turkey, N Africa.

Elimination of most of the tourist income on the Med coasts

Endangerment of the biodiversity and ecological balance of the sea

Cause for droughts/flooding seen with other dams https://en.wikipedia.org/wiki/Aswan_Dam

Massive population dislocation in the region of tens of millions

I can go on but the point is what would the benefit need to be to consider this project as net positive?

[simonh]

These are all good arguments for now, but if climate change progresses as feared at least some of them might become moot. Once sea levels have risen a few metres, say in a century or two, being able to lower the sea level in the Med might be seen as a positive. Changing environmental conditions could change the calculation in favour of plans like these.

[konschubert]

One could then put a hydroelectric power plant between the Atlantic and the Mediterranean Sea - the influx of water through the damn could probably be balanced by evaporation in the Mediterranean Sea... I haven’t done the math on it though.

[jessriedel]

Additional land and power, shorter transit time, a closer connection between Europe and Africa. Maybe the latter slightly increases the immigration rate from Africa, lifting millions out of poverty over a few decades. Maybe it decreases the risk of war in these places you list. Maybe the carbon-free hydropower averts a catastrophic negative feedback loop from climate change.

Neither of us have any idea, and listing the first thing that comes to our head hardly gets us closer.

[YeGoblynQueenne]

As a Greek person who grew up in the region, this conversation has an eerie tone, like hearing two plastic surgeons discussing whether I'd be better with higher cheekbones or with an aquiline nose and how much such surgery would improve my chances to find a mate.

So, could we focus on the fact that this was designed by a man who never lived in the region he wanted to terraform? I have no business advising German people how to change their countryside and that goes the other way too.

I don't really care about a cost-benefit analysis, either. This is just an uncalled for intervention that, er, that nobody called for.

[jessriedel]

I specifically mentioned rejecting this proposal out of hand for rights-based reasons earlier. You don't have to read our further cost-benefit discussion if you don't care about it or it makes you feel uncomfortable. I prefer not to focus on the things you would like us all to focus on.

[YeGoblynQueenne]

>> I prefer not to focus on the things you would like us all to focus on.

You mean, like what the people who live in the Mediterrannean actually think of this plan?

But, there is no realistic prospect to initiate this project unless those very people agree to it. So what is the point of discussing cost-benefit analyses, if that agreement is almost guaranteed to not be forthcoming?

I mean, it's not even a rights issue. If the people who live in the Mediterrannean don't want it terraformed, then it's not getting terraformed. Realistically speaking.

[jessriedel]

It is obvious that no one in this thread has any real-world influence on this plan being carried out. The discussion is purely academic, and is driven by the questions that are interesting to the people doing the discussing.

Furthermore, if you look at my comments, you will see that I don't actually care about the plan, and I don't have a position on whether the costs of the plan outweigh the benefits. The only point I am making is that the outcome of a cost-benefit analysis cannot be reliably guessed by appealing to one's intrinsic wisdom and listing some possible negative consequences in a grave voice.

I don't have any interest in discussing this further with you.

[hutzlibu]

Lots of land and electricity. That is something huge in densely populated europe.

But I also think the costs are bigger.

[runarberg]

Electricity, sure. Land, no. The reclaimed land will be highly salinated and unusable on top of the climate being very hot and very dry meaning the salinity level will be unlikely to change in the near future.

[tempguy9999]

> The reclaimed land will be highly salinated

The dutch I thought have done quite well with lots of land reclaimed from the sea. Why does it work for them, but not here?

[ceejayoz]

Dutch plans relied on pumping out those areas, not letting them dry out.

[Udik]

Not too sure about the difference. The water level would just drop, and the water simply flow away from the shallow coastal areas. I don't know what would salinity the water would have reached after dropping 200 meters but it's not the one you get if you simply let a volume of water to evaporate completely, which would be 100%.

[garmaine]

How is that relevant with respect to salinity?

[navaati]

Land, I'm not sure is at such a premium Europe-wise. There are vast swathes of unpopulated land in France, typically.

[mikeash]

To be fair, this project is so far beyond anything that’s been done that nobody is capable of doing an accurate cost-benefit analysis of it.