i have started when my capital was engulfed in jungle, and had 2 water squares it looklike this
J J J
J C J
WJW
J=jungle
W=water
C=capital
it ended up bieng vey good as a conected two ends of an ocean saving me potentially AT LEAST 4-5 turns for every boat in that area, not to mentionit was great for expansion, but anyway,my capital was baicaly jungle for 7-8 squares to the south, & 9-10 squares north. luckily after that there was great bonus grasslands, and some plains & floodplains, i pulled off a great space race win (greeks)i didn't clear most of it until the industrial age, just get out of it, there's probably some nice grasslands waiting for you