His late father, Jacques, was an oceanographer and engineer who plunged deeper into the ocean than any other person.

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Their most significant finding is that climate change means the gas is being released from more and deeper areas of the Arctic Ocean.

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But we are having to spend more oil to get oil, as we drill deeper, and drill in the deep water of the ocean.

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"I started to think about what would it take to go deeper, what would it take to go to full ocean depth - that was kind of the holy grail from an engineering standpoint, " he told BBC News.

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