Geo-engineering is only way to save our planet

Whenever I get the chance, I go diving. The whole family are divers, right down to the grandchildren: it’s one of the pretexts we use to get together. And we all know the coral reefs are dying.

There are still healthy reefs, and even after they have been bleached they can recover — but only until the next time that sea temperatures rise beyond their tolerance range. Half of the world’s coral reefs are already gone, and the destruction continues relentlessly. The northern 750 kilometres of Australia’s Great Barrier Reef were largely killed by heat stress last year. Global warming will kill almost all of the world’s coral reefs by 2050.

Prof. Madeleine van Oppen’s work at the Australian Institute of Marine Science and the University of Melbourne is therefore good news. Her team is trying to breed hybrid coral animals and algae that can withstand higher temperatures.

“It is a story of hope, rather than saying: ‘It’s all going to die and there’s nothing we can do about it,’ ” van Oppen said at Oxford University, where her team presented their latest research at a conference last week.

People worry about major interventions in the reef life, she concedes, “but it’s too late to leave them alone, given the pace at which we are losing corals ... It is only a matter of time before the next heat wave hits.”

She calls this “assisted evolution,” but it’s just an intense version of the selective breeding that people have been doing with domesticated species for thousands of years. Van Oppen’s team has been cross-breeding corals adapted to cooler waters with other species from warmer regions to create hybrids to withstand higher global temperatures.

They are also working with algae that live inside the coral animals and are their major source of food, because it is when the water gets too warm and the corals expel the algae that bleaching occurs. So one team member pushed the algae through 80 generations in the lab, selecting the most heat-tolerant in each generation. The final generation can live in water at 31 C.

The next step is to transplant these modified coral animals and algae onto living reefs, which will require regulatory approval. That may not be forthcoming right away, because there will naturally be concerns that these “evolved” animals and plants will out-compete the existing reef life.

They are not different species, however, and the one circumstance in which they are likely to out-compete the existing reef-life is precisely during bleaching events, when they are more likely to survive. But that, surely, is the point of the whole exercise, and there are enough parts of the world with damaged reefs that van Oppen’s team will get permission for its experiments sooner or later.

We are already in the situation, at least with regard to coral reefs, that James Lovelock, the creator of the Gaia hypothesis, forecast almost 40 years ago: that the human race will wake up one day to find that we have inherited “the permanent lifelong job of planetary maintenance engineer.” The self-regulating natural systems have been knocked out, and it’s up to us to regulate and maintain them.

We don’t yet even fully understand the ways that the systems we will have to manage actually work. But the changes we have wrought in the environment are overwhelming the ability of natural systems to maintain themselves in their stable and familiar forms, and so it will be up to us to keep them going.

This is low-tech geo-engineering, with little chance of major negative side effects if we get it wrong.

But the interventions in natural systems will get much bigger, and the penalties for mistakes much more costly, as time goes on. We are probably going to end up trying to regulate the temperature of the entire planet, with megadeaths as the penalty if we fail. But by then there will be no alternative.

— Gwynne Dyer is an independent journalist whose articles are published in 45 countries.