Costing the Earth debates one of the most important issues facing the planet that affects all of us: Where will our food come from in the decades ahead.

The world population is expected to rise to 9 billion by 2050. That's another 2.5 billion mouths to feed, roughly the number of people currently living in China and India today.

Tom Heap is joined by an panel to chew over the question of what the world will eat as populations rise, climate changes and vital resources are depleted.

The panel is made up of experts from the world of food and agriculture: Professor Charles Godfray from the Oxford Martin Programme for the Future of Food; Colin Tudge, the man behind the Campaign for Real Farming; new Groceries Adjudicator, Christine Tacon; Sean Rickard an economist who specialises in food and farming; Tristram Stuart: winner of the award for 'Best Initiative in British Food' at last week's BBC Food and farming awards, the food waste campaigner behind the Feeding the 5000 and Pig Idea projects.

With Tom Heap in the chair they'll be debating whether we should put our faith in huge industrial agri-industry to feed the ever expanding world population or could organic farming hold the key? Will genetic modification be embraced as famine takes hold? Will vast factory farms pop up to avoid people going hungry, or will future farming operations be more holistic and community based, with everyone doing their bit to produce food for their friends and neighbours? Will we need to turn to algae, lab-grown protein and insect farms to keep our bellies full or will the developed world enjoy an artisan-baked, craft-brewed lifestyle whilst the rest of the planet scrapes a living from depleted soils?

Presenter: Tom Heap
Producer: Martin Poyntz-Roberts.