Drawdown, which I reviewed last week, is a book with 100 solutions to climate change, each quantified and ranked for effectiveness. I was rather surprised by the top ten, especially given how much attention certain solutions get relative to others. So here it is, and all the technical details are if you want to see the maths:
- Refrigeration – the most effective thing we can do to help reverse climate change is dispose of fridges and air conditioning units properly, so that their HFC gases don’t escape into the atmosphere. I don’t think I’ve ever written about refrigeration on the blog here, which now seems like a major oversight and I will correct that in due course.
- Onshore wind – the most cost effective form of electricity generation, and therefore the cheapest way to displace fossil fuels. There is room for widespread adoption of wind power in many parts of the world.
- Food waste – everyone can agree that less food waste is a good thing, and when you factor in the emissions that go into producing what we throw away, as well as emissions from landfill, it’s at number three in the list of solutions.
- Plant-rich diets – or eating less meat, if you prefer. Of everything on the list, this is the one that most of us could make a start on right now, and make a serious dent in our personal carbon footprint.
- Tropical forests – forests in the tropical regions have the highest carbon uptake, but have been extensively cleared in recent decades. Restoring and protecting tropical forests would turn a source of emissions into a carbon sink, and have many benefits for people and development too.
- Educating girls – another surprise at how high this comes in, and again, it shouldn’t be controversial. Educating girls qualifies as a climate change solution because the more years of education women complete, the fewer children they tend to have. At 100% enrollment of girls in secondary school, the world population would be 843 million lower in 2050 than current projections, dramatically improving the chances of providing a decent way of life for everyone in a stable climate.
- Family planning – on a related note, providing contraceptives to all those that want them would also reduce the burden on the planet while improving opportunities for women.
- Solar farms – with their full life cycle considered, solar farms produce 94% fewer carbon emissions than coal power. The Drawdown research suggests that from 0.4% of global electricity, utility-scale PV could expand to provide 10% by 2050.
- Silvopasture – I’m not sure I’ve even heard the word before, but it’s “the integration of trees and pasture or forage into a single system for raising livestock.” In other words, you graze your sheep, cows or deer amongst the trees. This agroforestry technique gives good yields on the animals, sequesters carbon and restores soil, and has been practiced for thousands of years. The idea of clearing land of trees in order to raise cattle is starting to look really dumb.
- Rooftop solar – a second entry into the top ten for solar, rooftop PV has the advantage of being decentralised and suitable for off-grid applications. It could prove to be the easiest way for rural households without electricity to get the power that they need, making it a technology for everyone.
I should mention that if you were writing a list for reducing your personal carbon footprint, there are some things you’d definitely see on there – such as avoiding flying or reducing your car use. These things do feature in the Drawdown list, but they’re often scattered across several solutions. So reducing car use is addressed by trains, bus rapid transit, walkable cities, cycling and EVs. It’s not that they don’t matter or have been forgotten.
Here’s the top ten in its context, showing its relative impact and the next twenty solutions in the list. To see the whole list, I can recommend the book or an extended browse through the .