„Even with a target of 1.5 degrees we will still lose around half our warm water coral reefs."
When asked to reveal his favorite ocean, Hans-Otto Pörtner becomes pensive. And when he answers the question, it is not to name names, but to admit that he doesn't have a favorite. Every sea, he says, fascinates him, as does the life that teems below the surface. As an ocean biologist, that stands to reason.
But he is also a climate researcher and member of the Intergovernmental Panel on Climate Change, and as such, he studies the effects of global warming on the marine ecosystem and explores the role of our seas in cooling the planet. His news for those who are willing to listen, is not good.
"The ocean plays a decisive role for our climate," he said, referring to the fact that the great swathes of blue that connect our ailing landmasses has been absorbing 93 percent of the earth's heat for several decades. At its own great expense. In soaking up 30 percent of the CO2 we churn out into the atmosphere, our oceans have suffered from acidification.
The effects on the oceans, scientific studies show, will be dramatic. Scientists predict the loss of large areas of coral reefs - up to half of them even if the warming threshold is capped at 1.5 degrees. That has implications for the entire ecosystem, for fish stocks and coastal protection, and would be a disaster for people who live in coastal regions and depend on fishing for an income. It would, in fact, be a disaster for us all. Such is the nature of nature, of our dependence upon it - whether we realize it yet or not.
Pörtner, unsurprisingly against such a dramatic backdrop, is hoping Paris will deliver a 1.5 degree limit, though he recognizes that turning that figure on paper into reality would require both new technology and a final goodbye to outdated sources of fuel - such as coal.
Though he says he is not trying to tell delegates what they should be aiming for at COP21, he does go so far as to say that there is great room for improvement in terms of ensuring the right people are in possession of the right information.
"There has been no direct exchange between negotiators and scientists," he said. And although negotiators have the data at their disposal, he wonders to what extent they actually engage with it.
"I wish there were more of an exchange, both in the lead-up to and during these negotiations." In the absence of that scenario, he remains at the sidelines, shouting as loud as he can to give both science and the ocean a much-needed voice.