What the UN Secretary-General Nominees Reveal About Climate Change

Despite calls by United Nations member states and far beyond that the next secretary-general must concentrate on peace and security, climate has never left the scene in the race to lead the UN. Most candidates address climate change in their vision statements and all of them were questioned before the General Assembly on how they would handle it. Many expressed dissatisfactions with climate conferences, with one candidate proposing to reconsider the science on global warming.

The applicants therefore seem to agree that current efforts fall short of the crisis. Yet they disagree on why and what should be done about it.

Though the secretary-general doesn’t set emissions targets or climate finance, whoever is selected can pressure governments, convene actors and keep environmental issues central to the international agenda. Secretary-General António Guterres frequently used this platform to highlight the continuing emergency. His successor will inherit a UN pressured by financial, credibility and geopolitical crises, as extreme weather intensifies and rich countries cut support for the global South.

Eight candidates have presented their vision: Michelle Bachelet (Chile, supported by Brazil and Mexico); María Fernanda Espinosa (Ecuador, nominated by Antigua and Barbuda); Rafael Grossi (Argentina); Rebeca Grynspan (Costa Rica); Carolyn Rodrigues Birkett (Guyana); Macky Sall (Senegal, nominated by Burundi and Senegal); Olara Otunnu (Uganda); and Ivonne A-Baki (Ecuador, nominated by Tonga).

There was consensus among them, as presented in their respective informal dialogues with the General Assembly, on the gap between climate commitments and implementation. But the applicants’ different approaches to the problem reveal a tendency to shift blame to the multilateral process, while questions of justice could remain unresolved.

Promises and implementation

In her presentation, Espinosa questioned why, after three decades of Conference of the Parties, or COPs, emissions keep growing. Otunnu called the Paris Agreement historic but said implementation must accelerate. Grossi went further, criticizing COPs as too large and unmanageable.

Frustration with climate results is understandable. National commitments and promised funding remain far below what is needed. However, placing COPs at the center of the problem may obscure responsibility.

These annual conferences, held under the UN Nations Framework Convention on Climate Change (UNFCCC), originally produced the Paris Agreement, financing mechanisms and recognition of losses suffered by vulnerable populations, and implementation has gained traction in recent rounds. There’s room for improvement, but delegitimizing COPs enables those who are striving for reducing pressure for emissions cuts and the energy transition.

A-Baki’s positions raise an additional concern. She said she respects scientific consensus but argued that climate science and policy have become ideological battles that can “upend the lives of the very people we mean to protect.” Before the General Assembly, she went further, calling climate change “cyclical” and attributing worsening impacts mainly to population growth — with no scientific evidence.

Climate policies directly affect people’s lives. A transition that deepens inequality or shifts costs onto workers and developing countries is not just. But the discussion on policies must be based on the evidence accumulated by climate science. Human activity, chiefly fossil-fuel emissions, is the main driver of current global warming. We can debate which policies to adopt and how to share costs, but treating scientific consensus and arguments that downplay its causes as equivalent undermines the ability to confront the crisis.

Science, responsibility and justice

Responsibility for the climate crisis is not evenly distributed. Countries, companies and social groups carry very different historical burdens, and those who contributed least often face the worst floods, droughts and food insecurity. This is what climate justice addresses: Inequality at the center.

Bachelet makes this connection clearly, advocating financial-architecture reform that expands climate finance, eases access for developing countries, relieves debt and prioritizes grants over loans, so nations that caused little of the crisis aren’t forced deeper into debt to produce responses.

Similar concerns run through other proposals from the candidates. Espinosa criticized barriers to accessing climate funds and called for more adaptation financing. Otunnu warned against imposing new burdens on developing countries. Sall, in turn, proposed reviving Just Energy Transition Partnerships, though this model is criticized for relying heavily on loans.

Grynspan highlighted economic losses in small island states, while Rodrigues Birkett argued that the Security Council should treat climate effects as a driver of conflict.

These proposals share a fundamental question of climate justice: How should the costs of a crisis be shared when responsibility and impact are drastically unequal?

Who chooses the next leader?

 Another inequality exists in how UN leadership itself is chosen: In 80 years, no woman has held the post of secretary-general.

The 1 for 8 Billion campaign calls for states to consider only women candidates and for the next UN leader to be committed to feminism, human rights, sustainable development and climate action. The call for greater representation deeply aligns with climate justice, since Indigenous peoples, Afro-descendants and low-emission countries face disproportionate effects with little power in decision-making.

Formally, the General Assembly appoints the secretary-general based on a Security Council recommendation. But real power lies there: No candidacy can proceed against a veto by any of the five permanent members — China, Britain, France, Russia and the US. In practice, most countries merely ratify a decision already made by a few.

This opacity makes it all the more important to scrutinize what each candidate actually stands for on combating global warming. The next secretary-general will have little power to set climate policy alone but will have meaningful room to influence it — pressing states to honor emissions and finance commitments, pushing COP reforms that strengthen implementation without weakening the negotiating space and taking the climate debate beyond technical circles but always grounded in science.

The choice of the next UN leader will test states’ willingness to act on a crisis demanding faster, fairer and more ambitious solutions.