Delegates leaving the UNFCCC climate talks in Bonn earlier this month will have been under no illusions as to the task ahead. While progress was made in Germany over the two weeks of negotiations, the pace and ambition of the talks is not what it should be. With just 18 months to go to reach a new international climate agreement in 2015 in Paris, there is an urgent need to increase political will and deliver ambitious commitments to avoid dangerous climate change. We have been here before, in 2009, when there was widespread optimism that global leaders convening in Copenhagen would conclude a robust agreement to solve the climate crisis. At that time we were both Special-Envoys on Climate Change for the UN Secretary General and we watched with heavy hearts as global optimism faded and leadership failed.

This time must be different. To reach a robust agreement in Paris, we have to change the dynamics in the negotiation process. An injection of much-needed climate finance would signal a commitment to act, rebuild trust between the Parties and in the international process, and create a much more favorable context for an international agreement. Of fundamental importance is the capitalization of the Green Climate Fund (GCF). This fund, mandated in Copenhagen to support climate action on the ground, is now ready to receive contributions. There are three decisive reasons for immediate and substantial capitalization of the GCF:

1. Developing countries are mobilizing resources for innovative and transformative actions—the GCF will empower countries to bring these actions to scale.

Faced with the realities of climate change, developing countries are innovating to manage climate risk and kick start their transition to low carbon development. The GCF can provide the resources to scale up these actions.

African Risk Capacity is a ground-breaking insurance mechanism that has leveraged climate finance to enhance food security for hundreds of thousands of drought-vulnerable households in five African countries. Eight more countries are expected to take out insurance in 2015. This African Union-led venture has the potential to scale up to a multi-billion dollar portfolio in the years ahead, catalyzing the transformation from managing crises to managing risks and setting the stage for improved growth on the continent.

In Chile, innovation is at the heart of an initiative to explore possible future scenarios that contribute to the development and decarbonization of the country. A US$4 million effort over four years, the MAPS project combines the best science available with an organized and informed participatory process. At the core of the participatory process is a 90-person-strong scenario-building team with representatives of government, industry, academics, consultants and civil society. They shape solutions informed by both indigenous knowledge and international best practice. At the heart of the initiative is the realization that real, substantive change is needed, and that science and policy need to be engaged to find the best path for the country and its citizens.

A capitalized GCF can help to bring these initiatives to scale and protect lives and increase opportunity as a result.

2. Finances are urgently required to protect the most vulnerable countries dealing with the impacts of climate change.

The latest report of the Intergovernmental Panel on Climate Change (IPCC) shows us that the effects of climate change are already being felt. Global surface temperatures have been steadily warming, with the greatest impact on those who are least responsible for the causes of climate change. This is the injustice the Convention process seeks to address, and climate finance can help by safeguarding the rights of the vulnerable and ensuring equitable access to the benefits of a climate-resilient, carbon-neutral world.

The report of the IPCC’s Working Group II highlights the deficit that exists between global adaptation needs and the funds made available for adaptation. As such, the structuring of the GCF to aim for a 50-50 balance between adaptation and mitigation was a welcome decision. Immediate capitalization of the fund will allow for extensive and essential adaptation efforts to get underway.

3. A strong statement of intent must be made ahead of the 2015 climate agreement.

Just five-and-a-half years remain to meet the goal set in Copenhagen to mobilize US$100 billion of climate finance per year by 2020. Immediate capitalization of the GCF can send a signal that this goal will be met and allow urgently needed resources to flow to the countries and communities most in need.

The capitalization of the fund in the coming months achieves even more than the transformative outcomes of sensible investment. It would be an unmistakable declaration of intent, and of serious commitment, in advance of the UN Secretary General’s Climate Summit and COP 20 in Lima.

The mobilization of resources will be perceived as a statement of solidarity, signaling to vulnerable countries, in need of climate finance, that they can trust their negotiating partners and that promises will be delivered. For all Parties, it will build critical confidence in the process—a process where collective confidence and collaborative spirit have not always been apparent—and can ultimately create a positive context for the successful agreement of a new climate regime.

Christina Figueres, the Executive Secretary of the United Nations Convention on Climate Change (UNFCCC), has called for at least US$10 billion capitalization of the GCF by November. Many developing countries have called for $15 billion. Today, we want to echo those calls, to raise the ambition and commit resources on a scale commensurate with the climate challenge, without diverting funds away from essential development.

Looking back on Copenhagen now, it is clear that our inability to agree a successor to the Kyoto Protocol stemmed from a lack of political will, a lack of trust, and the absence of a sense of our shared humanity. The flow of resources into the GCF will rebuild trust in the process, focus Parties on the action needed to solve the problem, and galvanize the courageous leadership required to reach an equitable and ambitious climate agreement. Capitalized, the GCF will enable the leadership emerging from developing countries to catalyze innovative and transformative climate action.

The first meeting on GCF capitalization takes place at the end of this month. We call on developed countries to lead and to commit resources now, to set the scene for ambitious action by all countries in the preparation of national contributions to the new international agreement. The GCF is open for business, innovative actions await financing, and the start of a new phase of global climate action lies within our reach. Let’s not miss this chance.

Mr Ricardo Lagos, former President of Chile 2000-2006, President, Fundacion Democracia y Desarrollo and Mr Festus Mogae, former President of Botswana 1998 -2008, Member, African Union High-level Panel for Egypt, co-authored this blog post as members of the High Level Advisory Committee to the Climate Justice Dialogue.