By the end of the century, 30% to 50% of all species on Earth could go extinct. The planet could face catastrophic water shortages. And hundreds of millions of people will be displaced from their homes.

The reason for all this doom is simple — climate change. The way to avoid this doom is not.

Hundreds of fundamental changes have to be made to human society for global emissions to be reined in enough to avert the calamities of climate change.

Some ways of cutting emissions are so obscure and go after such entrenched habits that it’s hard to see how they can be carried out on a global scale.

Nonetheless, the best minds in the world are trying to figure out what needs to be changed and how these changes can be realized.

That’s essentially the purpose of the Paris climate agreement. All the countries in the world except Syria, Nicaragua, and now the US, have pledged to reduce emissions through this framework and are working towards individual goals.

Read More: 5 Consequences of Trump Dumping the Paris Climate Agreement

The architects of the arrangement are in a continuous process of determining the best tactics for countries to reach their goals.

Drawdown is a nonprofit coalition of scientists, advocates, politicians, and more, dedicated to doing just that.

Recently they determined the 100 best solutions for combating climate change and reducing emissions by assessing the costs of each action and calculating the amount of amount of carbon dioxide that would be averted.

Here are the top 10: (As a helpful guide, a gigaton is more than 6 million blue whales in weight.)

10/ Rooftop Solar — 24.6 Gigatons of CO2 Averted

Image: YouTube

Advances in technology, drops in manufacturing costs, and economies of scale have made solar panels available to nearly the entire world. The widespread adoption of panels by households can enable communities in low-income countries to “leapfrog” fossil fuels, similar to how many developing countries leapfrogged landline technology because of mobile phones.

Read More: Tesla’s Solar Roofs Are Officially For Sale – And They Look So Good

9/ Silvopasture — 31.19 Gigatons of CO2 Averted

Image: National Agroforestry Center

This ancient technique for raising livestock integrates trees into pastures, which dramatically curbs emissions from animals. It also regenerates ecosystems, creates new sources of food and income, and improves the health of wildlife. This method also allows farmers to better cope with the effects of climate change like drought.

8/ Solar Farms — 36.9 Gigatons of CO2 Averted

Solar energy cost $1,900 per watt in 1954. Today, it costs less than 65 cents and the price keeps going down as advances are made in technology. Solar farms have more potential than solar rooftops because they cover large swaths of space and capture more energy from the sun.  

Read More: The World’s Largest Floating Solar Panel Farm Is Now in China

7/ Family Planning — 59.6 Gigatons of CO2 Averted

Image: Lindsay Mgbor/Department for International Development

This isn’t about mandating limits on children. Instead, it’s about providing women with birth control and reproductive health options, which 225 million women in low-income countries say they want. By empowering women with education and health options, birth rates come down and the population strain on the planet falls.  

Read More: How Trump's Global Gag Rule Is Hurting African Women the Most

6/ Educating Girls — 59.6 Gigatons of CO2 Averted

Image: Flickr: Develop Africa

Global Citizen has said it before and we’ll say it again: educating girls is at the root of eradicating poverty. It also happens to be at the root of fighting climate change. When girls receive a full education, they have fewer and healthier kids, contribute more to economic growth, and are better stewards of the environment, among other benefits.  

Read More: Educating Girls Is the Key to Ending Poverty

5/ Tropical Forests — 61.23 Gigatons of CO2 Averted

Image: Pixabay: rosinakaiser

Tropical forests once covered 12% of the Earth’s land mass. Now they’re present on just 5%. Restoring tropical forests can sequester huge amounts of carbon, safeguard and replenish ecosystems, and provide sustainable incomes and sources of food.

Read More: Deforestation in Malawi Is So Severe the Army Needed to Step in to Stop It

4/ Plant-Rich Diets — 66.11 Gigatons of CO2 Averted

“If cattle were their own nation, they would be the world’s third-largest emitter of greenhouse gases,” Drawdown writes in their assessment. Shifting away from the Western meat-centric diet to one revolving around plants can drastically reduce emissions, while also promoting health and helping ecosystems flourish.

Read More: 11 Famous Chefs Who Are Trying to Save the World With Food

3/ Reduced Food Waste — 70.53 Gigatons of CO2 Averted

Image: Getty Images

Food waste accounts for 8% of global emissions and happens all along the food supply chain — from cultivation to storage to consumption. Creating better systems for processing and consuming food is a sensible and easy way to make a huge dent in global emissions.

Read More: 13 of the Best Ugly Fruits & Vegetables That Are Still Perfectly Good

2/ Onshore Wind Turbines — 84.6 Gigatons of CO2 Averted

Image: Flickr/ian munroe

Wind farms are easy to build, use little land, and generate significant amounts of energy at rates that rival fossil fuels. Today, nearly 4% of all electricity is generated by wind farms and this rate will continue to rise as investments continue to break records — 2016 saw the biggest increase of wind power generation in history.

Read More: A Chinese Firm Is Training Coal Workers in Wyoming to Run a Wind Farm

1/ Refrigerant Management — 89.74 Gigatons of CO2 Averted

Image: AP Photo/Desmond Boylan, File

Air conditioners cool down rooms and cars and fridges cool down food and beverages, but they both heat up the planet more than anything else in the world.

The Montreal Protocol phased out ozone-eating HCFCs and CFCs from these devices, but ushered in the era of HFCs. While this compound doesn’t cause the ozone to disintegrate, it heats the atmosphere at a rate 900 to 1,000 times more than CO2. More than 90% of such emissions happen at the end of a product’s life cycle, according to Drawdown, and better management systems can greatly reduce their impact.

Read More: 170 Countries Agree to Ban HFCs in Landmark Climate Change Agreement

The 2016 Kigali accord goes after HFCs and, alone, shaves 1 degree Fahrenheit off projected temperatures rises.


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