Smoke billows from a factory in Dezhou, Shandong province. To reach mandatory efficiency goals, the government had to take some extreme steps, including power cuts and limits on electricity supply in 2010. [Provided to China Daily]

A few years ago, Melinda and I visited a group of rice farmers in Bihar province of India, one of the most flood-prone regions in the country. All of them were extremely poor and depended on the rice they grew to feed and support their families. When the monsoon rains arrived each year, the rivers would swell, threatening to flood their farms and ruin their crops. Still, they were willing to bet everything on the chance that their farm would be spared. It was a gamble they often lost. Their crops ruined, they would flee to the cities in search of odd jobs to feed their families. By the next year, however, they would return - often poorer than when they left - ready to plant again.

Our visit was a powerful reminder that for the world's poorest farmers, life is a high-wire act - without safety nets. They don't have access to improved seeds, fertilizer, irrigation systems and other beneficial technologies, as farmers in rich countries do - and no crop insurance, either, to protect themselves against losses. Just one stroke of bad fortune - a drought, a flood or an illness - is enough for them to tumble deeper into poverty and hunger.

Now, climate change is set to add a fresh layer of risk to their lives. Rising temperatures in the decades ahead will lead to major disruptions in agriculture, particularly in tropical zones. Crops won't grow because of too little rain or too much rain.

Of all the people who will suffer from climate change, poor farmers are likely to suffer the most at a time when the world needs their help to feed a growing population. By 2050, global food demand is expected to increase by 60 percent. Declining harvests would strain the global food system, increasing hunger and eroding the tremendous progress the world has made against poverty over the last half-century.

I'm optimistic that we can avoid the worst impacts of climate change and feed the world - if we act now. There's an urgent need for governments to invest in new clean-energy innovations that will dramatically reduce greenhouse gas emissions and halt rising temperatures.

Many of the tools they'll need are quite basic: access to financing, better seeds, fertilizer, training and markets where they can sell what they grow. The Gates Foundation and its partners have worked together to develop new varieties of seeds that grow even during times of drought or flooding. The rice farmers I met in Bihar, for instance, are now growing a new variety of flood-tolerant rice - nicknamed "scuba" rice - that can survive two weeks underwater. Other rice varieties are being developed that can withstand drought, heat, cold and soil problems like high salt contamination.

All of these efforts have the power to transform lives. Still, a better seed or a new technology cannot transform the lives of farming families until it's in their hands. A number of organizations, including a non-profit group called One Acre Fund, are finding ways to ensure that farmers take advantage of these solutions. One Acre Fund works closely with more than 200,000 African farmers, providing access to financing, tools and training.

Yes, poor farmers have it tough. Their lives are puzzles with so many pieces to get right - from planting the right seeds and using the correct fertilizer to getting training and having a place to sell their harvest. If just one piece falls out of place, their lives can fall apart.

I know the world has what it takes to help put those pieces in place for both the challenges they face today and the ones they'll face tomorrow. Most importantly, I know the farmers do, too.

The author is co-chair of the Bill & Melinda Gates Foundation.

Project Syndicate