U.S. and Chinese mayors are discussing climate action this week. One idea sure to come up: sustainability reporting. In fact, cities should disclose sustainability data as a minimum legal expectation if they want to be part of the roughly $3.7 trillion U.S. market in municipal securities.

Boston, Massachusetts and Warsaw, Poland are among the many cities making a wide range of city data very accessible – including statistics on energy and water use and recycling. Whether you care about efficiency, education, prosperity, safety, or health, isn’t it desirable to be able to check your community’s stats and trends?

This is especially true when it comes to environmental impacts. The idea of getting to #NetZero harm – the practically self-evident idea that humanity has to neutralize its negative effects on the climate and ecosystems – is finally getting traction. Eliminating environmental harms requires better efficiency and begets innovation, and can lead to prosperity and improvement in well-being. Cities – foremost among them coastal cities – have much to lose and much to gain from unmitigated climate chaos, and therefore have to be champions for better measurement and tracking of environmental data. “If you can’t measure it, you can’t manage it and you can’t fix it,” as former New York City mayor Michael Bloomberg has summarized.

Even for the most strictly short-sighted, financially-motivated, and narrowly self-interested among us, awareness of the long-term viability of a city is something that a reasonable investor should expect when purchasing municipal securities, as explained in City Sustainability Reporting: An Emerging & Desirable Legal Necessity (soon to be published by Pace Environmental Law Review).