Ground Up

Cities with over 1 million inhabitants can be up to 12 degrees hotter than surrounding areas during summer nights. The tonnes of steel, concrete and glass in our cities create “heat islands”. The consequences can be dire. How are engineers combatting the positive feedback loop that is climate change?

July 2021 was the hottest month in recorded history.

While the world is rallying for high level, top-down measures to combat climate change, it may be too little too late. Engineers are taking the steps now to deal with more intense and more frequent heatwaves.

Engineers? What damage does a heatwave even do to a city? Big blocks of concrete, glass and steel have traditionally proved to be pretty durable structures. Well, cities tend to create “heat islands”. Given how much heat concrete and asphalt absorb, dense cities become giant ovens. Cities with over 1 million inhabitants can be up to 12 degrees hotter than surrounding areas during summer nights. Let’s go through the consequences.

Firstly, electricity demand skyrockets. AC usage rises by up to 2% for every 0.6-degree celsius rise in temperature. Cities with millions of people increasing their energy consumption by up to 30% on any given day place an incredible burden on energy suppliers.

On a personal, observable level sleeping becomes incredibly difficult. The body needs to cool before falling asleep. Increased temperatures are proven to lead to shorter, shallower sleep. Our body releases a stress hormone that prevents us from sleeping. The effects of poor sleep are increasingly being broadcast. In the past, we looked at the effect of poor sleep on our productivity. Poor sleep costs the US US$411b in GDP.

With cities growing and temperatures rising, the positive feedback loop is exacerbated.

Urban planners are forced to redesign buildings, roads, and footpaths. For example, cities from Athens to Los Angeles are implementing “cool pavement”. In its simplest form, cool pavements reflect heat rather than absorbing it by using lighter colour surfaces. It sounds like an obvious and easy change but re-engineering a cost-effective, easily producible alternative to asphalt is a difficult task. The flow-on effects are incredible though. Cooler streets mean cooler air and buildings reducing the reliance on air conditioning and reducing smog levels. In fact, a 20% in increase in reflectivity of pavement is expected to drop temperatures in LA by up to 0.5 degrees celsius. Cool pavements also reduce the reliance on street lighting and reduce electricity usage. It adds up across millions of miles of roads in cities globally.

Want more?

You know what to do

Insights, trends and company deep dives delivered straight to your inbox.

Stake logo
Over 7,000 5-star reviews
App Store logoGoogle Play logo

Subscribe to our free newsletters

By subscribing, you agree to our Privacy Policy.

Stakeshop Pty Ltd is registered as an overseas company in New Zealand (NZBN: 9429047452152), and is registered as a Financial Service Provider under the Financial Service Providers (Registration and Dispute Resolution) Act 2008 (No. FSP774414). We hold a full licence issued by the Financial Markets Authority to provide a financial advice service under the Financial Markets Conduct Act 2013. However, the content on this website has not been prepared to take into account any of your individual objectives, financial situation or needs. To the extent you require further information about the relevant New Zealand legislation that may apply, or require specific advice, please contact your legal and/or financial adviser (as appropriate). The information on our website or our mobile application is not intended to be an inducement, offer or solicitation to anyone in any jurisdiction in which Stake is not regulated or able to market its services. At Stake, we’re focused on giving you a better investing experience but we don’t take into account your personal objectives, circumstances or financial needs. Any advice is of a general nature only. As investments carry risk, before making any investment decision, please consider if it’s right for you and seek appropriate taxation and legal advice. Please view our Terms & Conditions, Privacy Policy, Financial Advice Disclosure and Disclaimers before deciding to use or invest on Stake. By using the Stake website or service in any way, you agree to our Privacy Policy and Terms & Conditions All financial products involve risk and you should ensure you understand the risks involved as certain financial products may not be suitable to everyone. Past performance of any product described on this website is not a reliable indication of future performance. Stake is a registered trademark under class 36 (New Zealand).

Copyright © 2024 Stake. All rights reserved.