My parents concieved and birthed me in the usual fashion for placental mammals, and I grew to betray that heritage; when you complain of the Northwest chilliness, you may blame me for overshooting my mark. Photosynthesis does not come easily to those of us with iron in our veins, and this is why I pay my greenhouse debt in the House of Prochlorococcus. We get along well; we really are quite closely related.
The House of Prochlorococcus is my geodesic home, an accidental homage to the sixty-atom carbon molecule. Prochlorococcus and I live inside, and sometimes I prop a pane open to grab more greenhouse gases.
Though nobody aspires for their children to be the servant of their inferiors, we are all in a respiratory sense the slaves of those who can photosynthesize. I am both keeper and dependent, and Prochlorococcus is the breadwinner of the household. The glucose-winner, actually, for nothing is so sweet as sugar, plucked carbon by carbon from the electronically reluctant air. I sail our half-submerged polymer globe north and south seasonally, catching the edges of tropical storms bereft of lands on which to run aground. We follow the temperature bands for optimal carbon fixation, chasing someone else's dreams of planetary cold.
Ithulba is a plane of water, its population a raft of polygonal amphibious eggs blowing across it. Each of us is a refugee from civilisation tending a precious desalinated photosynthetic pool.
We are not terraformers; we are reformers. I was a student when the Atmospheric Cascade last cycled, or at least when the reply arrived: the farthest star had finally received transmissions from the Ithmolai nuclear disaster. The fashion for labor-intensive biogenic modification expanded into the new vacuum of the planet-habitability industry, and the Reclamation Project recruited croppers from all over. My family lost to Nai Ed Molai, I signed up and didn't care where the RP sent me sent me.
Now I live on Ithulba, primordial home of our people and site of the Reclamation Project's first planetary-scale biogenic reclamation operation. Ithulba, current home of pond scum and social misfits floating around in plastic snow globes. The RP makes it sound much better in the advertising material:
Ithmolai has shown the ultimate folly of Cascade methods: the absence of consciousness from the physical process itself allows the dangerous illusion of impartiality. Only by being and living with the habitability efforts can we oversee and control every aspect of the process. Join RP as we improve the worlds through the sweat of our brow.
I don't chant when I aerate Prochlorococcus, although a lot of my co-croppers do. It makes for a pleasant, if muffled, chorus on the occasions when we hit the same current.
When my assignment came, I thought it meant I was due to be executed and composted for one of the earlier reclamation projects. I breakfasted on dessert and reported in a very broken-in tunic. For most of us, "Ithulba" was a colloquialism for "before you're concieved"; our aeration chants are the songs of the redeemed.
The planet would be habitable with a few kilotonnes of topsoil on a raft; it would make a decent cash-crop farm. But someone thinks this might really be Ithulba, and they cannot tell until the bellies of the continents stand from the water's salty surface again. They need people as crazy and as dead as me to drain the ocean by rebuilding the ice caps, vaster than empires and more slow.
Prochlorococcus is angry sometimes. We colonised this world, drowned it, abandoned it for other worlds, and now we have tinkered with her inner genetic world so that we could re-colonise this one. We have both denigrated her purpose and elevated her to new photosynthetic heights. You left this world, she says. There was no time for anything I was or loved to evolve ways to survive. No mermaids singing, each to each; your ancestors fled or drowned, and dragged me along. Every lovely green thing drenched in saline, drinking out its life water; every swaying sea plant under more layers of water than it could gather sunlight through.
Something may yet survive in the deep, but it has a sulfur metabolism or worse; the atmospheric oxygen didn't change between our ship's departure and arrival, which was a few hundred years in planetary time.
Maybe I should put in for a respite. Maybe when I got back, some real time would have passed locally, the oceans would have dropped some fractional measurement, and single-celled organisms wouldn't talk to me. But no matter if I'm losing it; Prochlorococcus is right: even after the lands have risen, the Ithulba found will never be the Ithulba of my people's collective unconscious. Besides, my grasp of reality is irrelevant, as long as I can still optimise photosynthesis.
There's actually nothing stopping us croppers from hooking our photocells together and joining up permanently, or from hooking up ourselves, or from hitching out of here on the next supply ship. Nothing except for a para-religious (or hell, overtly religious) fervency, and the knowledge that the worlds we left were well and truly gone in the dilation of time when the 0.5c transport started up its drive. Who goes streaking across time and space to settle down and start a family?
It's a big planet; maybe someone is building that cash-crop raft and an anchor with a very long chain. But whatever each of us has now, we would leave behind again if we took any extrasystem jaunts. The sentient-being condition has always been such that your life collapses behind you if you neglect it, but time dilation exponentiates the situation. If you want a lasting effect, you have to dive deep instead of going skipping around the systems.
My story is the same story each of us has: faith in redemption, through the works of our hands and the spirit of our colleagues. In one sense, it doesn't matter whether or not this is Ithulba; in another, it so very much does. This work would have merit and poetic justice on any world flooded by the rising tides of our greenhouse folly, but it would not be coming home.
Our stories since the transport landed are all the same: we have all lain on the tops of our photocells under the raining sky; we have all felt the horizon, so close and so vast; we have all contemplated the irony of us imitating the chloroplast on a grand scale. We are the same in the way that the air and water are homogenous; each of us takes a different random walk to a similar destination. Our paths—our pasts—don't matter. People who think their pasts matter don't jump onto ships with speeds that approach a decent fraction of c. And of course the past matters, or we wouldn't be trying to drain Ithulba, but our personal pasts are meaningless individually. We are the bank, the wash of sand, the ocean, the little people. We are each an evolutionary dead end, except for whoever might be building that habitat raft; we only make a difference when we throw our lots in together, shoulder to the climate change. We are here now, ostensibly for the survival of our species as it spreads back to the ruined planets, but mostly because the same way that every child in every system wants to grow up and find Ithulba, each of us wanted to believe in something, in each other, in something bigger than ourselves.
There are worse forms of self-delusion. It's a slow suicide, but most of them are. Sometimes it's better not to think too hard.
The scientists who will excavate Ithulba's lands are not yet born in my time, and the vast open oceans I know will be gone forever. The Ithulba that is now—the Ithulba that is now my home—will be gone, and they will sing the world's old name in their songs again: Nai Ed Hulver, home of wished-for memories.