The dark and moody storm clouds that have lingered over Durban this past week have been a pretty fair representation of the chances of a climate change agreement being reached at COP 17.

We've had nearly 20 years of negotiations under the UN Climate Convention, and this is now the seventh year that countries have met to discuss ways of cutting greenhouse gas emissions after 2012. The pledges currently on the table are so weak they will lead to 5°C global warming that will cause catastrophic climate change threatening the lives and livelihoods of millions of people. How did it come to this?

The huge storm which hit the city last night is reported to have killed eight people. Scientists say there'll be more extreme weather like this to come. Developing countries, who are least able to prepare for or recover from climate change-induced challenges like this, are relying on the world to wake up.

Of the 28 countries worldwide considered to be at 'extreme risk' from climate change, 22 of them are here in Africa. 13 million people here are already being affected by a drought so bad that it's causing crops to fail and people to go hungry.

Developing nations have shown greater ambition than industrialised nations for cutting emissions worldwide, but they desperately need the big polluters to get on board. Rich developed countries, with less than 15% of the world's population, are responsible for as much as three quarters of the pollution in the atmosphere today. It's only fair that they lead emissions cuts first and fastest - we're calling for them to commit to cuts of at least 40% of 1990 levels by 2020, without offsetting.

As anyone who helped Friends of the Earth bring about the UK's Climate Change Act will know, the best way to drive meaningful action across nations is to make it legally binding. This means the world urgently needs to agree to a second commitment period of the Kyoto Protocol. And the EU must to sign up to it unconditionally, with ambitious targets, to get the other big polluters to follow suit - or in the case of the US, act equivalently.

Nothing else will achieve the scale of emissions cuts with the urgency scientists tell us is needed. Bilateral agreements and 'carbon clubs' for rich countries have been suggested as alternatives to Kyoto. But they would be driven by short-term political and economic interests - and would be inadequate, with weak and ineffective pledges that would continue to see emissions rise.

Similarly, carbon trading has proved to be ineffective at slashing global emissions. It shifts the burden to the poor and keeps rich countries locked into high-carbon infrastructure instead of driving forward the low-carbon industries of the future. Speculating on carbon markets is also extremely risky business - Friends of the Earth research has shown it could even lead to another financial collapse.

But we can't bail out the planet like we bailed out the banks. The cost of a climate catastrophe will come at a price we can't afford to pay.

That's not to say that other national and international efforts to cut emissions aren't needed at the same time - we should be tackling climate change at all levels.

This past week I've spoken to hundreds of ordinary people who have travelled here from all over the continent for Dirty Energy Week, organised by Friends of the Earth in South Africa. Men and women, old and young, they're already suffering the impacts of climate change in their everyday lives and have come to Durban to demand change. Limiting the rise in global temperatures to no more than 1.5°C is critical for saving lives in their homelands.

Dirty energy, after all, is something South Africa knows much about. This year the World Bank lent $3.4 billion to this country's government to build the world's fourth largest coal-fired power station. To make matters worse, it will provide cheap electricity to polluting industries, instead of bringing power to homes. The locals are furious - and they're determined to drive forward greener energy alternatives.

I've visited local communities here that have set up their own schemes, on- and off-grid, using clean energy from the sun. It's a similar story across the continent: from small dams to wind turbines, people are meeting their energy needs through community-owned power. But with 40% of the world's population still without access to energy, many need financial help to get started. We need to channel more public funds via the UN to help poor countries adapt and develop cleanly.

Today, the first day of the talks, bright sunshine has broken through the gloomy skies. Could it be a sign of good things to come?

This is no time to gamble on flawed solutions. We need to put massive public pressure on governments to do the right thing. People power is the only way we'll drive through the emissions cuts that are so badly needed. That's why we're urging people to go to our website foe.co.uk, and help Friends of the Earth call on the EU to show real leadership at the climate talks here in Durban.