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Christian Mumenthaler is group chief executive officer at Swiss Re, one of the world’s largest reinsurers, where he has shaped the company’s industry-leading sustainability strategy over the last 25 years. Recently the company collaborated on a methodology that helps insurers and reinsurers quantify their portfolios’ greenhouse gas emissions, and created a protocol encouraging insurers to set decarbonization targets. He is also co-chair of the World Economic Forum’s Alliance of CEO Climate Leaders.

What is the single most important action you think the public, or a specific company or government, needs to take in the next year to advance the climate agenda?

I’m already seeing encouraging progress on Scope 1 and 2 emissions [for a company’s operations and energy use], but Scope 3 [supply chain emissions] can represent more than 90% of a company’s total emissions. Because of the sheer scale of Scope 3 emissions, tackling them is crucial. One key way of addressing them is to ask suppliers to adopt a path to net zero if they want to continue to supply your goods and services in the future. These are so-called Scope 3 upstream emissions and taking such action would have a strong multiplier effect. Another part of the solution is to tackle the greenhouse gas emissions of your own products and services, the so-called downstream Scope 3 emissions.

What sustainability effort do you hope will gain popularity with the general public this year, and why?

We are seeing already today in many countries positive signs of a take-up of more sustainable practices when it comes to renewable energy use, electric appliances, and more sustainable heating systems. In this context, one of the most important levers is to massively scale-up investment in renewable energy at an individual, company, and country level. In addition, governments can help accelerate this by scaling up power networks and streamlining permitting and regulatory processes.

Where should climate activism go in the next year?

Ideally, I would like to see climate activism moving to a more solutions-oriented approach and engaging in a constructive dialogue with corporations on rapidly advancing climate solutions and sustainable business practices. I’d like to see people using the power of their decisions to drive collective action. There are market-ready solutions already available, but also new approaches and innovations coming all the time.

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