Opinion

How to avoid climate disaster  

photo_camera Cómo evitar un desastre climático 

There are two numbers related to climate change that are worth knowing. The first is 51 billion. The second is zero. Fifty-one billion is the approximate number of tonnes of greenhouse gases the world puts into the atmosphere each year. Although the figure may increase or decrease slightly from year to year, it generally tends to grow. This is the situation today. Zero is the amount we should aim for. To slow warming and prevent the worst effects of climate change - which will be very harmful - we humans must stop emitting greenhouse gases into the atmosphere. If this sounds complicated, that is because it will be.  

The world has never undertaken such a colossal task. Every country will have to change the way it does things. Virtually all activities of contemporary life involve the release of greenhouse gases and, as time goes on, more people will be able to access this lifestyle. This is a good thing, because it means that the conditions in which people live are improving. However, if we do not change other factors, the world will continue to produce greenhouse gases, climate change will continue to worsen and its impact on humanity is certain to be catastrophic. However, this can change. I believe that a number of factors can be changed. We already have some of the tools we will need and, for those we do not yet have, everything I have learned about climate and technology leads me to be optimistic about our ability to invent them, implement them and, if we act fast enough, avert a climate disaster.  

Two decades ago, I never imagined that I would one day speak publicly about climate change, let alone write a book about it. My professional background is in software, not climate science, and I now work full-time with my wife, Melinda, at the Gates Foundation, where we focus all our efforts on global health, development and education in the United States. I became interested in climate change indirectly, through the problem of energy poverty. In the early years of the 21st century, when our foundation was just getting off the ground, I began to travel to low-income countries in sub-Saharan Africa and South Asia to learn more about child mortality, HIV, and other serious problems we were fighting. However, my focus was not exclusively on disease.  

When I flew to major cities, I would look out the window and ask myself: "Why is it so dark out there? Where are all the lights I would see if I flew over New York, Paris or Beijing? In Lagos, Nigeria, I walked down unlit streets where people huddled around bonfires they had lit in old metal drums. In remote villages, Melinda and I met women and girls who spent their days gathering wood to cook over an open flame in their homes. We met children doing their homework by candlelight because they had no electricity at home.  

"When it comes to climate change, the poor have the most to lose".  

I discovered that nearly a billion people lacked a reliable electricity supply and that half of them lived in sub-Saharan Africa (the picture has improved somewhat since then; today, approximately 860 million people have no electricity). I thought of our foundation's motto - "Everyone deserves the chance to lead a healthy and productive life" - and how hard it is to be healthy when the local clinic doesn't keep vaccines refrigerated because the refrigerators often don't work. It's hard to be productive when you don't have enough light to read by.  

And it is impossible to develop an economy that provides job opportunities for all without large amounts of reliable and affordable electrical power for offices, factories and telephone answering services. Around the same time, the late scientist David MacKay, a professor at Cambridge University, shared with me a chart showing the relationship between income and energy use - between a country's per capita income and the amount of electricity consumed by its people. The diagram, in which per capita income was represented on the horizontal axis and energy consumption on the vertical axis, made it clear that the two factors are closely related.  

As I absorbed all this information, I began to think about how the world could manage to provide cheap and efficient energy to the poor. It didn't make sense for our foundation to tackle this huge problem - we needed to keep it focused on its core mission - but I started brainstorming with some inventor friends. I read several books on the subject in depth, including the enlightening books of scientist and historian Vaclav Smil, which helped me understand how essential energy has been to modern civilisation.  

At that time, I was not yet aware that we had to go to zero. Rich countries, responsible for much of the emissions, were starting to pay attention to climate change, and I assumed that would be enough. My contribution, or so I thought, would be to advocate for reliable energy to be available to the poorest. For a start, they would be the main beneficiaries. Cheap energy would not only provide them with light at night, but also cheaper fertiliser for their land and cement for their houses. And when it comes to climate change, the poor have the most to lose. These are mostly farmers who are already living on the edge and would not be able to cope with more droughts and floods.  

My mindset changed in late 2006, when I met with two former Microsoft colleagues who wanted to start energy and climate-focused non-profit organisations. They were accompanied by two climatologists well versed in these issues, and the four of them showed me the data linking greenhouse gas emissions to climate change. I knew that these gases were causing temperatures to rise, but I assumed that there were cyclical variations or other factors that would naturally prevent a climate catastrophe from occurring. Moreover, I found it hard to accept that temperatures would continue to rise as long as humans continued to emit greenhouse gases, in whatever quantity. 

"Imposing a target to reduce our emissions - but not to eliminate them - will not be enough".  

I went back to the group several times to clarify further doubts. In the end, I understood: the world needs to generate more electricity for the poor to prosper, but without emitting more greenhouse gases. The issue then seemed even more complex to me. It was no longer enough to provide cheap and reliable energy to the poor; it also had to be clean energy. I continued to study everything I could get my hands on about climate change. I met with experts on climate and energy, agriculture, oceans, sea levels, glaciers and power lines, among other fields. I read reports published by the Intergovernmental Panel on Climate Change (IPCC), the UN body that establishes the scientific consensus on the issue. I watched Earth's Changing Climate, a great video series of lectures given by Professor Richard Wolfson and available as one of The Great Courses. I read Weather for Dummies, which remains one of the best books on climate I have come across.   

One thing that became very clear to me was that today's renewable energy sources - wind and solar, above all - could go a long way to reducing the problem, but that we were not yet doing enough to implement them. It also became clear to me why they alone are not enough to get us to zero emissions. The wind doesn't blow all the time, the sun doesn't shine around the clock, and we don't have affordable batteries that can store the amounts of energy a city needs for as long as it takes. Moreover, electricity production accounts for only 27 per cent of all greenhouse gas emissions. Even if we were to make major battery breakthroughs, we would still have to deal with the remaining 73 per cent.  

In just a few years, I have come to three conclusions:  

1. To avoid a climate disaster, we need to reach zero emissions.  

2. We must apply the tools we already have, such as solar and wind energy, faster and smarter.  

3. We must create and commercialise cutting-edge technologies to help us achieve our goal.  

The case for zero was, and still is, a strong one. If we do not stop putting greenhouse gases into the atmosphere, temperatures will continue to rise. There is a particularly illuminating analogy: the climate is like a bathtub that is gradually filling up with water. Even if we reduce the trickle to a trickle, the water will eventually overflow the rim and spill over. That is the disaster we need to avoid. Setting ourselves the target of reducing our emissions - but not eliminating them - will not be enough. The only sensible target is zero.