51 billion tonnes of greenhouse gases are released into the atmosphere every year worldwide. Zero is the number we are aiming for: this is the only solution, if we want to stop global warming and avoid the worst effects of climate change. Every country will be forced to change its habits; almost every activity of modern life, from agriculture to manufacturing, to transport, will be affected by this change, because every one of those activities involves the emission of greenhouse gases. Unfortunately, setting the goal of simply reducing emissions will not be enough: just like a bathtub that fills with water, decreasing the jet to a simple drop slows down the catastrophe of ensuing overflow, but it does not prevent it. To eliminate emissions altogether, large scale change is required, using all the tools at our disposal, including government policy, current technology, new inventions, and the ability of private markets to supply products to immense numbers of people. During the COVID-19 pandemic, annual emissions fell by 5%, which is about 48 to 49 billion tonnes of carbon dioxide instead of the usual 51. It seems like a big reduction, but at what cost? Millions of people lost their lives, and many more lost their jobs. If you think about it, the reduction in emissions is surprisingly small in a situation where almost the whole world shut down.
This slight reduction is proof that we cannot achieve climate neutrality, or even come close, simply by flying, driving, and going out less. There are two things we can do. First of all adaptation: we can try to minimise the impact of changes that are already underway, or that we know are coming, for example by developing new varieties of crops that can withstand drought or flooding. The other thing we can do is to mitigate: we simply need to stop adding greenhouse gases to the atmosphere, and the richest countries will have to go fast, pledging to eliminate them completely by 2050. To do this, we need new tools to tackle climate change: zero impact ways of producing electricity and goods, of growing food, of cooling or heating environments, and of moving people and goods around the world. The key to fighting climate change is to make clean energy as cheap and reliable as the energy obtained from fossil fuels.