Coffee production could be cut by up to 50 per cent in a few decades because of the effects of climate change, a report has found.

The coffee industry is worth $19 billion worldwide, with more than 2.25 billion cups of coffee consumed every day and nearly half of all Australians drinking coffee regularly.

But the report, A Brewing Storm, showed unless action was taken, the effects of climate change would result in supply shortages and increased prices.

"We're fearful that by 2050, we might see as much as a 50 per cent decline in productivity and production of coffee around the world, which is not so good," said Molly Harriss Olson, the chief executive of Fairtrade Australia and New Zealand, which commissioned the report.

John Connor, CEO of the Climate Institute which compiled the report, said there was a range of ways climate change was impacting coffee.

"I guess it's a story in other agricultural produce as well, but in particular for coffee," he told ABC NewsRadio's Sandy Aloisi.

"It's not just the heat, which is a big factor which is driving some of the regions where coffee is produced uphill.

"We're also seeing extra diseases increasing and being able to go up into those areas.

"We're already seeing some of those pests increasing their range and we're already seeing higher temperatures affecting production and productivity."

Concerns for farmers depending on crops

"It's also affecting productivity because the higher temperatures are affecting both the physical and mental health of those that are working on the coffee plantations," Mr Connor said.

Ms Olson said small changes in the climate could dramatically affect farmers' coffee crops.

"Our concern is primarily for the 25 million farmers out there whose entire livelihoods depend on this incredibly important global commodity," she told 774 ABC Melbourne's Jon Faine.

"These are among the most marginalised and poor communities in the world. They typically live on less than $2 per day and mostly have less than an acre of land on which they are growing their crops."

Mr Connor said higher temperatures were affecting the physical and mental health of coffee plantation workers. ( ABC News: Eric Tlozek )

How will climate change impact coffee drinkers?

Mr Connor said the cost and quality of coffee was "likely to pay the price of inaction on climate change".

Mr Connor said the cost and quality of coffee was at risk. ( AFP: Noel Celis )

"For Australians wanting to drink their coffee, it's going to choke up supply lines — we could see higher prices as well as challenges of getting the coffee itself, but flavour and quality is likely to be impacted as well," he said.

Mr Connor said some coffee organisations had recognised climate change's threat, introducing climate-neutral offerings.

"People should have a look around, ask about what's going on with their coffee and are the people producing it paying attention to this issue," he said.

"But of course it also comes back to calling on Governments and companies to take action on climate change.

"Because we've got to build a new economy that doesn't threaten things in our lifestyle such as our coffee."