Floating in the port of Los Angeles, a strange-looking barge covered with pipes and tanks contains a concept that scientists hope to make waves: a new way to use the ocean as a vast carbon dioxide sponge to tackle global warming. Scientists from University of California Los Angeles (UCLA) have been working for two years on SeaChange -- an ambitious project that could one day boost the amount of CO2, a major greenhouse gas, that can be absorbed by our seas. IMAGES AND SOUNDBITES