One of the first projects will help coffee farmers
Coffee farmers in Uganda will receive help adapting to climate change through a partnership with Wales.
The assembly government will provide a grant as part of the project under a United Nations scheme to link parts of the developing world to rich nations.
The three-year scheme involving the Mbale region in Uganda will be unveiled by First Minister Carwyn Jones at the climate conference in Copenhagen.
One project is a tree nursery to provide shade for coffee plants.
Mr Jones said: "Most people in the region are subsistence farmers whose livelihoods are acutely sensitive to the changes in the weather that they have seen in recent years.
"Coffee is the region's biggest export, providing a livelihood for thousands of people.
"If temperatures in the area rise by just 2°C, then they will be unable to grow the crop.
"Industrialised countries like ours have a moral duty to help these regions prepare their own plans to adapt and prepare for our changing environment."
The Department for International Development is providing £100,000, the assembly government £75,000 and the Wales-based Waterloo Foundation - which gives grants to green projects in the developing world - another £50,000.
Mbale district chief executive Andrew Mawejje said: "Farmers in our region have been dependent on the behaviour of birds and insects to know when the rains will come and when to plant their crops.
"Since our climate started changing around three years ago the birds and insects have also changed their behaviour.
"We have done little or nothing to cause climate change yet we are the first to suffer from its consequences."
Environment Minister Jane Davidson said the project would provide real, on-the-ground assistance, preparing communities for the changing world around them.
Hilary Thomas from the Pont project in Pontypridd which has been linked with Mbale for three years explained climate change could have a big impact on Ugandan coffee farmers in the future.
"They are on the slopes of one of the highest mountains in East Africa and as climate change happens one effect is the rise in temperature," she said.
"And that means that coffee will either have to be grown further up hill to maintain the temperatures that are needed, or something is going to have to be done to save the coffee plants or perhaps grow them in slightly different ways so they can maintain their yields."
Ugandan project worker Apollo Mwenyi said people there were "fearful" about climate change.
He said: "All our livelihood we rely on agriculture, that is the land and the weather. So if changes take place like they are doing now, we are completely scared for our lives and the future of the children."