In part, that is because British Prime Minister Tony Blair, has chosen to focus the British presidency of the G-8 on these two key issues.
But in part, too, it is because global warming and aid relief for Africa are issues that have captured the popular imagination worldwide.
Hundreds of thousands of people attended the Live 8 concerts at the weekend and billions watched them on television. Hundreds of thousands have taken part in the Make Poverty History campaign. More are gathering in the Scottish capital, Edinburgh, today.
That amounts to big pressure on the world leaders gathering at Gleneagles. Bob Geldof, the organiser of Live 8, has made clear what he expects them to deliver.
"I want to see the agenda of the commission for Africa enacted and that calls for a doubling of aid by 2010 to Africa to $25 billion and 100 percent cancellation of debt to the poorest countries and a trade pact at least beginning to end export subsidies and from the African side good governance," Geldof said.
On the surface, the prospects of a deal being hammered out on poverty reduction in Africa look reasonable. Last month, the G-8 agreed on a debt relief package worth $40 billion and in Denmark yesterday, Bush suggested the United States might be ready to give more aid – although he made it clear there were conditions.
"We've said we'll give aid, absolutely. We'll cancel debt, you bet, but we want to make sure that governments invest in their people, invest in the health of their people, the education [of] their people and fight corruption," Bush said.
The organisers of the Make Poverty History campaign are not impressed. They say the G-8 countries need to increase their aid spending to 0.7 percent of GDP if the UN's plan to halve world poverty by 2015 is to have any chance. The United States spends a mere 0.17 percent.
Simon Wright, a political officer for ActionAid, one of the organisers of the Make Poverty History Campaign, told RFE/RL that the G-8 were falling far short.
"When we started the Make Poverty History campaign and started putting pressure on the G-8, we were talking about a doubling of aid for next year -- an instant doubling of aid, which we think is needed. At the moment, they're talking about committing an extra $50 billion by 2010 and 2010 actually is the date by which we think their countries should be getting to 0.7 percent of their GNP being committed to aid rather than that lower figure," Wright said.
But if the outlook on poverty reduction is looking grey, the prospects for a breakthrough on climate change at Gleneagles look distinctly gloomy. Bush does not appear in the mood to compromise.
"I recognise that the surface of the Earth is warmer and that an increase of greenhouse gases by humans is contributing to the problem. Kyoto didn't work for the United States and, frankly, it didn't work for the world as many developing countries weren't included in Kyoto. I've told our friends in the G-8 that Kyoto would have wrecked our economy," Bush said.
Nothing much to cheer Blair there. He's banked his reputation on a breakthough on poverty and climate change and had hoped for a payback from Washington for British support on Iraq. And yet, Bush did offer a glimpse of a possible way forward.
"You see, I think there's a better way forwards. I call it the post-Kyoto era, where we can work together to share technologies, control greenhouse gases as best as possible. Listen, the United States for national security reasons and economic security reasons needs to diversify away from fossil fuels and so we're putting out a strategy to do just that and I can't wait to share it with our G-8 colleagues," Bush said.
Not much, perhaps, but, on climate change, it's likely to be the best that's on offer at Gleneagles this week. And if it allows a face-saving communique, Tony Blair, at least, will breathe a sigh of relief.