Every few years we see an attempted revival of the airship, usually for ' heavy freight ' purposes, or for AEW though it would make such a tempting target I hope an unmanned version might be possible for that !
I believe the modern descendants of the Zepellin co. have a fairly viable smallish job, with designs for a very large one if they get funding.
I seem to remember there's a problem supplying / producing enough Helium, though that's probably a WW1 throwback, and strong winds are still going to be a snag.
Suspect the actual manufacture of the envelope, engines etc may still not be very 'green' but I doubt it would mess with the Ionosphere !
I rather fancied the British 'Skyhook' - nothing to do with the Harrier scheme of the same name - of years ago, which had a semi ( ? ) rigid envelope and was shaped like a flying saucer, which might be less vulnerable to crosswinds - less useful volume too ? - and would be great for buzzing drunk hippies near Stonehenge.
I think it had a central ducted fan job for the vertical component, but either it was a gleam in some mad designer's eye or may have been the old story of a world beater which didn't get funded...
Though I'm all for aviation and suspect there may be a future market for the airship, I reckon a much 'greener' freight transport system for most jobs is a decent canal network, as still seen in Europe - not the piddly little UK system.