The increase in electricity supply will be met mainly through solar and wind. Photo: / Cifor CC BY-NC-ND

Science confirms that students are right – we can act now

State-of-the-art Climate Model “One Earth” backed by the Leonardo DiCaprio Foundation maps out a feasible pathway to keeping global warming below 1.5°C – joining the dots between energy strategies and nature conservation measures for the first time.

The new climate movement kicked off by Greta Thunberg is getting more and more traction. And with this success, critique is growing and climate sceptics are starting to push back. But those people are running out of factual arguments and using bullying tactics instead. In its 2 May 2019 edition The Guardian documented the disgraceful bullying by two right-wing web editors. Aditya Chakrabortty writes that “The hounding of Greta Thunberg is proof that the right has run out of ideas”.

Fortunately, the youth climate movement is not alone and scientists around the world support their case. Climate change is not a possible future scenario. Its happening, and we can do something about it.

Climate and energy scientists have created many models to stay within the 1.5°C limit advised by the IPCC, but nearly all have relied upon Bio-Energy with Carbon Capture and Storage (BECCS) – which is not proven at scale and displaces agricultural land – while some advocate for bizarre geoengineering solutions like Solar Radiation Management (SRM), which involves spraying chemicals in the air to block sunlight.

Indeed, this year has seen a flurry of stark climate warnings, with the Intergovernmental Panel on Climate Change describing the havoc that 1°C of global warming is already wreaking. After decades of fossil fuel consumption, the degradation of forests and natural ecosystems, and the release of other greenhouse gases, we are seeing the real-world manifestations of a more volatile climate: increasingly common floods, droughts, hurricanes and wildfires; poor air quality as a public health emergency; rampant deforestation leading to habitat loss and increased carbon emissions.

So, for the past two years, with support from the Leonardo DiCaprio Foundation, I have led a research program at the University of Technology Sydney, in collaboration with the German Aerospace Center and the University of Melbourne, to find a solution to achieving the 1.5°C limit without geoengineering. The outcome, a high-ambition climate plan which, for the first time, brings together energy strategies and nature conservation measures, was showcased in Davos this week.

Using a cutting-edge energy modelling tool and greenhouse gas model, we show the possibility of meeting 1.5°C through a switch to 100% renewable energy by 2050 and an expansion in energy storage and efficiency measures, together with natural climate solutions (NCS) like reforestation and agricultural practices to reduce emissions. This research lays the scientific foundations for a ground-breaking new climate initiative from LDF, published in early 2019.

At its heart is the large-scale electrification of heating and transport. Almost 90 percent of all transport energy comes from oil used in inefficient combustion engines, which will be replaced by efficient electric drives powered by renewable electricity. Heavy-duty trucks, freight trains, shipping and aviation will use synthetic fuels – produced by renewable energies – and limited biofuels, with oil being phased out by 2050.

The increase in electricity supply will be met mainly through solar and wind, which are already becoming more viable than coal and gas. The solar market grew 29.3 percent in 2017, bringing total operating capacity to 405 GW – 89 percent of which was installed in the last seven years. Offshore wind costs are falling, and turbines are getting bigger; it will not be long until one wind farm can power a whole city. Our projection that renewables can provide around 70 percent of electricity demand in 2030 and 100 percent by 2050 looks ever more achievable.

Crucially, it is possible to switch to 100 percent renewables by recycling parts of the gas infrastructure. After 2030, the gas industry can be converted into hydrogen using much of the same equipment and pipelines – with some technical adjustments – and employing many of the same workers.

Added to the renewables surge will be a major expansion in storage – pumped hydroelectric and batteries – and a global efficiency program centred on insulation, efficient lighting and strict efficiency standards for all appliances.

Finally, natural climate solutions must play a pivotal role. On its own, the emissions reduction brought about by renewables will not be enough. But if natural carbon sinks – forests, mangroves, and grasslands – can be kept intact, they will absorb about half of the emissions we need. And through a moratorium on deforestation, restoration of degraded forests, grasslands, and wetlands, and better agriculture practices, we can ensure enough emissions are absorbed to reach the 1.5°C goal.

What we need now are policy signals showing serious commitment to a greener future. Energy companies and investors need stable policymaking on renewables to feel confident that their investments will pay off. A number of countries have already pledged to phase out coal by 2030 and committed to ambitious renewables targets. But many key political leaders are dragging their feet, either because of a failure to see beyond traditional infrastructure, to grasp the dangers posed by climate change, or to understand the economic potential of the zero-carbon economy – or all of the above.

With some countries blocking the IPCC report and shamelessly promoting fossil fuels, it is crucial that decision makers can see there is a desirable pathway to a cleaner jobs-generating economy, a better quality of life for citizens, and proper protection for our natural world.

Meanwhile, the students are getting prominent support from Sir David Attenborough. For his audience at the World Economic Forum at the end of January 2019 in Davos, Switzerland, his message could not have been clearer: our natural world is in a desperate state of crisis – and we urgently need a global plan to fix it.

The Global Plan is there: The One Earth climate model is ground-breaking in that it shows the 1.5°C target can be achieved through a rapid transition to 100 percent renewables by 2050 (65% by 2030), alongside a major conservation effort to increase the resilience of natural ecosystems and help ensure greater food security. This includes a moratorium on land conversions by 2030 and 400 GtCO2 of ‘negative emissions’ from forest and land restoration (shown in gold below the zero line), which pulls carbon dioxide out of the atmosphere and stores it in trees and soil.

The One Earth Climate Model provides a detailed global plan and all the results can be accessed for free on a dedicated website and an open-access book. We have all the knowledge and the technology we need to make this shift, right now. However, we might not have the required politicians needed to implement this plan. But change is possible. It is not too late. Yet.

Dr Sven Teske
University of Technology Sydney, Institute for Sustainable Futures /Australia

The One Earth climate model (LDF 1.5 scenario) documented in Achieving the Paris Climate Agreement Goals (Teske, ed. 2019), shows the possibility of staying below the 1.5°C climate threshold. The IPCC special report Global Warming of 1.5˚C (SR1.5) calls for a carbon budget of 400 GtCO₂ to maintain a chance of staying below the threshold of 1.5°C in global average temperature rise, adjusted to account for additional warming since the beginning of the industrial era (circa 1750). The budget for a good chance (>67%) of 1.5˚C is 175 GtCO2, accounting for a buffer of 100 GtCO2 for biosphere feedbacks in the second half of the century, such as melting permafrost, which is achieved by 2075. This is the first climate model to offer a chance of lowering global temperatures to 1.4°C by the end of the century without geoengineering.


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