chief heat officer noun [C]
UK /ˌtʃiːf ˈhiːt ˌɒf.ɪ.səʳ/ US /ˌtʃiːf ˈhiːt ˌɑː.fɪ.sɚ/
someone who has overall responsibility for dealing with the rising temperatures in a city caused by climate change

Miami has one – so does Athens. Now Freetown, the capital of Sierra Leone, has appointed Africa’s first chief heat officer – a mother on a mission to shield her city and her kids from the chaos of climate change … The 34-year-old was appointed this week to combat rising temperatures and come up with everyday ways to cool the sweltering streets of the city she has always called home.
[climatechampions.unfccc.int, 9 November 2021]

carbon insetting noun [U]
UK /ˌkɑː.bən ˈɪn.set.ɪŋ/ US /ˌkɑːr.bən ˈɪn.set̬ɪŋ/
the activity of making changes within a company to reduce the damage its activities cause to the environment

Many of us already know that carbon offsetting means investing in carbon reduction or sequestration projects in order to compensate for your own emissions. Carbon insetting is a similar idea, but the crucial difference is that the offsetting happens in an area over which your organisation has some control. For example, while traditional offsetting might involve choosing a renewables project to invest in, carbon insetting might involve setting up your own renewables project on site.
[secrhub.co.uk, 15 July 2020]

eco-city noun [C]
UK /ˈiː.kəʊˌsɪt.i/ US /ˈiː.koʊˌsɪt̬.i/
a city that has been designed to minimize the impact it has on climate change and the environment

Now, Medellin wants to reinvent itself again – this time as Latin America’s first “eco-city” with wide-ranging initiatives in renewable energy, transportation, housing, water management and waste. ​​As governments and investors around the world direct funds towards pandemic recovery efforts, cities like Medellin are taking the opportunity to simultaneously set a climate-friendly agenda for years to come.
[aljazeera.com, 31 August 2021]

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