eco-geek.org says Iron fertilization creates algae blooms which absorb CO2 naturally, a form of carbon sequencing which is happening in antactica along side melting glaciers. So although they are spending billions to install alternative energies on antactica bases its possible that nature is already at work for us.
Besides, according to NPR news from KCRW today, fighting global warming may already be a losing battle as it would take nearly 1000 years to reverse the damage done. I think we all know whats important is that we do what we can Now to prevent its worsening in the future time.