Foronestory,Ithoughtupascenariowhere crop-harvestresiduesunkintotheocean combatsglobalwarming.Iworkedupsome formulastoseeifitwaspossibleand checkedwithsomecolleaguesandfoundit wasn'tasfaroutasIinitiallythought. Youdescribeyourwritingas'hard'science fiction. Whatdoesthatmean? Inhardsci-fi,youcan'tviolateany...