For smallholder farmers, climate change is no future threat. It is happening now. As I learnt on a recent visit to Mali, a smallholder farmer, Issa, talked to me about how his farming methods have been affected by the unusual changes in the patterns of rainfall in his district. The rains on which farmers depend are starting later and finishing earlier.
A similar worrying story of farmers facing more uncertain conditions is being heard in many areas on our continent. The worst, however, is yet to come.
Scientists warn that temperatures could exceed the maximum which major staple crops will tolerate. Rainy seasons will become even shorter and more erratic, seriously worsening Africa's already grave food crisis.
Given these changes and the scientific consensus over what will happen, Mali's farmers struggle to understand why so little had been done to tackle climate change even though they amazingly managed to rise up to the challenges.
This local knowledge and wisdom must guide those in power to work towards a more balanced and sustainable world. I share their frustration. We are witnessing an abject failure of leadership which, unless urgently repaired, will leave a terrible legacy for future generations.
This is why the climate conference underway in Durban is so important. Durban sadly might not see the universal agreement we need to limit greenhouse gas emissions to the level required to hold temperatures rises to below 2Â°C.
But it must build momentum towards a fair and inclusive agreement both to cut emissions and to help protect communities from the impact of climate change already underway.
Putting in place proper climate finance is critical to these goals. Progress is being made in designing the Green Climate Fund, which must be launched at Durban. Yet, to become an effective tool that can meet the needs of Africa and other poor countries, the Fund must meet two challenges.
First, wealthy countries must not be allowed to break their promises to the most vulnerable on the planet who have not caused climate change. The $100 billion of commitments made in Cancun last year need to be delivered.
To this end, the Green Climate Fund must receive sustained and predictable funding in the range of several tens of billions of dollars per year.
In spite of their promises, wealthy countries are unlikely to provide adequate and predictable multi-year funding for the Green Climate Fund from their national budgets. This is why I support innovative financing solutions, such as a fair maritime bunker fuel tax, a levy on airline tickets, or the Financial Transaction Tax.
Each of these mechanisms can provide the long-term funding needed to support climate finance.
Second, the Green Climate Fund must not only finance mitigation in advanced emerging countries. Adapting to the unavoidable consequences of climate change is vital to Africa's future. It requires the scaling-up of effective and proven development programmes.
We must therefore put adaptation and, in particular, African agriculture at the heart of the fund. We have already seen how, through access to new techniques, drought-resistant crop varieties and financial support, small-holder farmers in Africa can dramatically increase yields and improve their resilience to the vagaries of the harsh climate they live in.
The Green Climate Fund must finance such programmes by working with African Governments, private sector, international donors and, above all, small-holder farmers, including both men and women.
If implemented right, the Green Climate Fund can become a critical tool for investing in a uniquely African Green Revolution which in turn will accelerate wider development across the continent.
This needs to include increased funding for research into Africa's unique agricultural challenges and to put results into practice. Robust national strategies for farming and rural communities need to be supported in a way that brings in additional private financing.
The Durban conference becomes a crucial test of the ability of our leaders to look beyond narrow national and short-term interests. The opportunity for progress must not be wasted. Next time I visit Mali, I would like to bring good news of tangible progress made in the fight against climate change to Issa and other farmers.
The world will be watching the deliberations in Durban, and African farmers rightly expect no less than real support in their endeavour to survive in an increasingly hostile climate.
- Kofi Annan is chair of the Africa Progress Panel and AGRA.