Colleges, Columbia included, value progress in terms of grades/GPA–meaning that a few subpar middle school and freshman year grades won’t hurt you. My school does send certain middle school grades (I took classes that were high-school level), so I would check with your guidance counselor to see if those grades will be submitted.
You have a good array of ECs, and it would be great if you can find a way to integrate them (i.e. maybe expand the science section of your paper and encourage your CS/engineering friends to get involved). Seeing that environmental science and journalism seem to be your main passions, I would actively pursue them throughout the next year and apply for as many awards/competitions as you can. If you’re interested in writing, there are several competitions worth checking out (Scholastic Art and Writing, NCTE, etc.).
If you haven’t already, check out Columbia’s Science Honors Program! I don’t know much about it (I’m sure there are CC threads for more info) but I know it’s selective and adcoms look favorably upon it. Out of my two friends who attended the program, one was accepted ED and the other deferred (later accepted)–which I’ve heard is common among other members of the program.
If you get your standardized testing in line and expand on your ECs, I think you have a fair shot! Also thank you for your kind comment on my thread 
It seems too often that these posts get more bitter commentary than constructive criticism!