Airbus has announced it will attach sails to one of its transport ships to increase fuel efficiency.

Over the past decade, both the United States and Europe have made major strides in reducing their greenhouse gas emissions at home. That trend is often held up as a sign of progress in the fight against climate change.

Walmart’s current goal is to achieve zero waste in their Canada, Japan, U.K. and U.S. operations by 2025. The retailer’s 2018 sustainability report says that by the end of last year, Walmart had diverted 81 percent of its U.S. waste from landfills, and 78 percent globally. Here’s a closer look at the company’s approach.

The scale of the problem is staggering. Each year, 1.6 billion tons of food worth about $1.2tr are lost or go to waste — one-third of the total amount of food produced globally. To put the figure in perspective, that is 10 times the mass of the island of Manhattan.

On Chilean water regulator Oscar Cristi’s desk in Santiago, a small white espresso cup teeters atop piles of documents and loose folders that appear on the point of collapse, perhaps an apt metaphor for the growing water crisis in parts of the Andean country.

The stakes are high. Africa currently holds the highest prevalence of the world’s undernourished people and has among the lowest agricultural yields in the world. The continent will double in population to hold an estimated 2.5 billion of the world’s nearly 10 billion people by 2050.