DF2014 Talk:Ocean

Levels getting initialized?

I'm playing on an Arctic Ocean site without disabling cave-ins, and a layer of about a dozen levels of ice keeps getting wiped every time I retire the fort to play on a different site. I've been trying to channel down to the rock in the ocean floor, but this ice layer keeps erasing my efforts. I mean it works while I'm playing the ocean fort actively, but the moment I retire and (later) unretire, the game turns those levels back into pristine ice, and only those levels, excavations above and below are left mostly alone discounting the usual retire/unretire shenanigans.

...There's a logical explanation for that, right?

Arctic Ocean Screw Pump irrigation

I tried to flood a room under two z-levels of surface ice with water from a screw pump, but the pump just formed a 1-block Ice Wall in front of the output end of the pump, and that was it. And apparently the game does not consider tiles under the ice as underground. As in all the way down to the ocean floor. So if you can somehow keep the water from freezing, it looks like you can farm surface crops in the ice layers.

...Or not? I did manage to flood a room at a low enough z-level where my tunnels filled with water on unretire. The farm plot says I don't have seeds for this location. Probably because aboveground crops don't grow on freezing biomes.

Might work if I could find an area of temperate ocean, maybe?

Arctic ocean zero-point embark (a.k.a. Sea Ice NULL challenge)

1. Embark close to caravan time. If dwarven, starting on the last two weeks of summer should give you enough time to make a trade before your dwarves die of thirst. Human caravans arrive in summer so if you're playing humans via a mod, adjust to the last two weeks of spring, etc. You can control your embark time somewhat by repeatedly retiring and unretiring your site, or by playing a different fort for a while then retiring it in time to start this one. By default, retiring moves the entire world's time by two weeks.

2. Immediately pause the game so you can assign labors, then deconstruct your wagon. Unpause.

3. Build: a butcher, a tanner, and a craftsman's workshop. Make a food stockpile, then slaughter your draft animals. Make bone crafts out of ALL the bones, hooves, etc. (and totems out of the skulls) so you have something to trade to the caravan. Deconstruct the butcher and build a kitchen. Make lavish meals out of the meat.

4. Your dwarves will tan the hides. Once they finish, deconstruct the tanner, then build a farmer's workshop. Spin the hair into thread.

5. Once the meals are cooked, deconstruct the kitchen and build a leatherworks. Make bags out of the leather.

6. On the last day of summer, deconstruct the three workshops and build a trade depot. You can save at this point if you want to be anal about crafting up to the absolute last minute you can before the caravan arrives. Otherwise, wait for the caravan. Note that you still have time to craft even after the caravan arrives: on your first trade, you can buy a pick and mine ice, or buy a piece of construction material, and then build workshops to continue making trade fodder until the caravan leaves.

7. Once the caravan arrives, have your broker go to the depot, then open the trade screen. If you can't see the prices, close it again without trading. Just doing that gives an unskilled broker the Appraisal skill, so once you open the trade screen again you should see prices.

8. Put EVERYTHING up for trade. Buy a pick, all the brewables you can afford, and at least one barrel (preferably empty and low-quality, since it's more cost-effective to buy brewables instead of booze). Buy all the wood and stone you can, and an egg-layer if there are any in stock. If you can afford an anvil, buy one. Note that traders want around 100% profit (i.e. double the listed price of the item) or they might refuse to trade.

9. Build a still and make booze for your dwarves. You can continue to craft trade fodder. Take care to mark your brewables and booze as uncookable.

10. Tunnel down to water and hollow out a fishing area.

...and proceed as normal.

Retrieving items that have fallen to the seafloor

...Okay, I think I mostly got it now, so I better record it somewhere so I don't forget.

What you want to do is to tunnel 1 z-level below, to one space diagonally away from the item, build a floodgate there, link to a lever so you can open it, then carve a ramp diagonally up to the item. The item will fall onto the ramp, and flow through the diagonal gap, but since pressure doesn't work diagonally, you don't end up flooding your fortress instantly. Once the item gets pushed by the water past your floodgate, pull the lever to close it.

If you happen to have already tunneled through the space underneath a submerged item, you can still retrieve it by building an up stair on the space underneath, box the stairs in with walls and build a floodgate diagonal to it, then dig a channel on the item's space. Your digger will stand on the up stair and make a hole under the item.

...Except I notice that if I try to retrieve a corpse from the seafloor that way, then revive the unit with full-heal -r, the unit teleports to its place of death, meaning back to the seafloor-- and stays there not noticing the ramp leading to safety. So what you need to do is to watch until your digger is almost starting to dig, and revive the corpse then, so the revived unit is still alive when the ramp is carved. Units that aren't insane will actively try to escape the water once they drop into the tunnel. Berserk units tend to go after your digger. Units that are other kinds of insane are a tossup. Most of them don't even drop down, but if they do, the water will push them to relative safety. And then the melancholy ones will look for a cliff to jump back into the sea from. (In any case, if you're using dfhack for with revives anyhow, you might as well use gui/teleport too.)

This will unfortunately not work with items that are on the map edges, because you can't carve them into ramps. For those, you might want to bring an unbreathing/waterbreathing adventurer down and pick them up yourself. (...Or designate for dumping and use autodump to save yourself all the tunneling and flooding.)

Oh, and somewhat unrelated, but if an item gets stuck in a door in a flooded hallway, you can carve a ramp under the door, and the item will fall to the lower level, allowing the door to close while leaving the tunnel underneath dry.