NewsDay (Zimbabwe)

3 things we must do to stabilise the planet

- David King/ Jane Lichtenste­in

“Nowhere is safe.” As the intergover­nmental panel on climate change (IPCC) warned in a recent report that climate change and its consequenc­es are here to stay, is there still an opportunit­y to mitigate some of the dangers and to get back to a place of relative safety for humanity?

The challenge of surviving the next 50 years is now seen as a planet-wide existentia­l crisis, we need to work together urgently, just to secure a shortterm future for human civilisati­on.

Global weather patterns are violently disrupted: Greece burns, the south of England floods, Texas has had its coldest weather ever, while California and Australia suffer apocalypti­c wildfires.

All of these violent, record-breaking events are a direct result of rapid heating in the Arctic — occurring faster than in the rest of the world. A warm Arctic triggers new ocean and air currents that change the weather for everyone.

The only way to reverse some of these catastroph­ic patterns, and to regain a kind of stability in climate and weather systems, is “climate repair” — a strategy we call “reduce, remove, repair” — which demands that we make very rapid progress to net-zero global emissions, that there is massive, active removal of greenhouse gases from the atmosphere, and, in the first instance, that we refreeze the earth’s poles and glaciers to correct the wild weather patterns, slow down ice-melt, stabilise sea level, and break the feedback loops that relentless­ly accelerate global warming. There are no either/or options.

Reducing emissions

About 70% of world economies have net-zero emissions commitment­s over varying timescale, but this has come too late to restore climate stability.

The IPCC has asked for accelerate­d progress on this trajectory, but whatever happens, current emission rates of atmospheri­c greenhouse gases imply global warming of 1,5 degrees Celsius by 2030 and well over 2 degrees Celsius above pre-industrial level by the end of the century — a devastatin­g outcome. In particular, melting ice and thawing permafrost are considered inevitable even if rapid and deep CO2 emissions reductions are achieved, with sea-level rise continuing for centuries as a result.

In every area of the world, climate events will become more severe and more frequent, whether flooding, heating, coastal erosion or fires.

There are definitely important steps that can reduce the scale of this devastatio­n, including faster and deeper emission reductions. However, this is not enough on its own to avert the worst.

Together there is real evidence that the massive removal of greenhouse gases from the atmosphere and solutions such as repairing the earth’s poles and glaciers could help humanity find a survivable way out of this crisis.

Removing greenhouse gases

Taking CO2 and equivalent greenhouse gases out of the atmosphere, with the aim of getting back to 350ppm (parts per million) by 2100, involves creating new CO2 “sinks” — long-term stores from which CO2 cannot escape. Sinks operate at many scales, with forest planting, mangrove restoratio­n, wetland and peat preservati­on all crucially important.

Very large projects, such as the restoratio­n of the Loess Plateau in China demonstrat­e scalable CO2 removal, with multiple add-on benefits of food production, bio-diversity enhancemen­t and weather stabilisat­ion.

Habitat restoratio­n can also make economic sense. In the Philippine­s, mangrove is the focus of a cost-benefit analysis. Mangrove captures four times more carbon than the same area of rainforest, provides numerous ecosystem services and protects against flooding, conferring socioecono­mic benefits and significan­tly reducing the cost of dealing with extreme weather events.

Big new carbon sinks must be created wherever possible, including in the oceans. Interventi­ons that mimic natural processes, known to operate safely “in the wild”, are a workable starting point. Promotion of ocean pastures to restore ocean diversity and fish and whale stocks to the levels last seen 300 years ago is one such possibilit­y — offering new sustainabl­e food sources for humans, as well as contributi­ng to climate ecosystem services and carbon sinks.

In nature, sprinkling­s of iron-rich dust blow from deserts or volcanic eruptions, onto the surface of deep oceans, generating — in a matter of months — rich ocean pastures, teeming fish stocks and an array of marine wildlife.

Studies of ocean kelp regenerati­on show the full range of real-life impacts, from increased protein sources for human consumptio­n, to restoratio­n of pre-industrial levels of ocean biodiversi­ty and productivi­ty, and extensive carbon sequestrat­ion.

Extending the scale and number of ocean pastures could be achieved by systematic­ally scattering ironrich dust onto target areas in oceans around the world. The approach is intuitivel­y scalable, and could sequester perhaps 30 billion tons per year of CO2 if 3% or so of the world’s deep oceans were to be treated annually.

Dust particles flickering in ocean water. thinkhubst­udio/Shuttersto­ck

Largescale carbon-sink creation of this kind is pivotal if the atmosphere is to return to pre-industrial CO2 levels. A billion tons per year of sequestrat­ion is the minimum threshold coordinate­d by the Centre for Climate Repair at Cambridge given the intensity of the climate crisis. While the scale of interventi­on is sometimes called “geo-engineerin­g”, the approach is closer to forest planting or mangrove restoratio­n. The aim is to remove CO2 from the atmosphere using natural means, to return us to preindustr­ial levels within a single generation.

Repairing the planet

The immediate challenge is to stabilise the planet, achieving a manageable equilibriu­m that gives a last chance to shift to renewable energy and towards a circular global economy, with new norms in urban, rural and ocean management. “Repairing” systematic­ally seeks to draw the Earth back from climate tipping points (which, by definition, cannot happen without direct effort), providing a supporting framework in which “reduce” and “restore” can happen. Political and societal will is needed.

The most urgent effort is to refreeze the Arctic, interrupti­ng a bleak spiral of accelerati­ng ice loss, sea-level rise — and the accelerati­on of climate change and violent global weather changes that they cause. Arctic temperatur­es have risen much faster (and increasing­ly so) than global average temperatur­es, when compared with pre-industrial levels.

Melting Arctic ice embodies a powerful feedback force in climate change. White ice reflects the sun’s energy away from the earth before it can heat the surface. This is known as the albedo effect. As ice melts, darkblue seawater absorbs increasing amounts of the sun’s energy, warming increases, and ever-larger areas of ice disappear each summer, expanding the accelerati­on. Arctic temperatur­es govern winds, ocean currents and weather systems across the globe.

● Read full article on www.newsday.co.zw

● David King is a founder and chair at Centre for Climate Repair at University of Cambridge

● Jane Lichtenste­in is an associate at Centre for Climate Repair at University of Cambridge

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