Hold the frappuccino and put the latte back down - you may need to start weening yourself off them. In the not too distant future, climate change looks set to threaten the world's coffee and cocoa supplies.

For caffeine and chocolate addicts, it could mean that in a matter of decades their daily indulgence could become a luxury they can no longer afford.

Starbucks, the global coffee giant, is so concerned about its crop that it will be briefing Congress in Washington on Friday. So far, its head of sustainability, Jim Hanna, has been canvassing the Obama administration to act on climate change with little success.

Hanna told the Guardian his frustrations that if conditions continue as they are, there is "a potentially significant risk to our supply chain, which is the Arabica coffee bean".

Even now, Starbucks's farmers, who are mainly in Central America, are already feeling the effects of a changing climate, with severe hurricanes and more resistant bugs reducing crop yields, he said.

Cocoa beans are in just as much peril as their coffee bean counterparts. Over half of the world’s chocolate comes from Ghana and Côte d’Ivoire. According to a study by scientists at the International Center For Tropical Agriculture (CIAT), rising temperatures in these countries could send chocolate prices soaring, as supply will surely dwindle.

The cocoa report predicts a one-degree Celsius temperature rise by 2030. This increase alone would be enough to inhibit the growth of cocoa pods in West Africa. The region's dry season is also predicted to become more intense, to the point that it will disrupt plant growth.

Scientific research may be able to find a way to develop heat-tolerant cocoa plant varieties, though investment has not yet been forth-coming.

It is not just western consumers that will be detrimentally affected. CIAT's Dr Peter Laderach explains that in writing his report he was highlighting the effect it will have on local farmers.

He explained that: "Many of these farmers use their cocoa trees like ATM machines. They pick some pods and sell them to quickly raise cash. The trees play an absolutely critical role".