BasserDan, as a geologist can tell you in last few hundred thousand years CO2 has been higher and lower than now multiple times. The human effect on CO2 is real, but CO2 has followed climate in past not led it, ice cores are clear on that.
That aside there are real problems. Are you familiar with Project Baseline?
There is a new product that will be on Kickstarter on Feb 1 called BLU3 that will hook into Project baseline so divers will effortless gather data for reef protection.