Back in 2018 while walking around the bustling city of Bangalore, India’s historical high-tech hub, I noticed a series of small sensors mounted on objects around the city. These sensors were put there by the Bengaluru Healthy Air Coalition to measure air quality in real time and send data to the World Air Quality Index. To my surprise, I later learned the sensors placed inside Cubbon Park – a beautiful, green oasis amidst the urban congestion near my guesthouse – registered air quality readings nearly 50% better than just outside the park on the main causeway.  

Extreme Heat and Air Pollution

One of the most significant drivers of human health is air quality. In fact, according to the WHO, air pollution has become the world’s single largest environmental health risk. It’s often the case that areas with higher average temperatures have worse air quality, and this occurrence disproportionately impacts developing countries in Africa, Latin America, Asia, and Oceania. Countries in the equatorial region generally experience some of the hottest temperatures on Earth due to their proximity to the sun. The countries that experience the highest average temperatures year-round include Saudi Arabia, Oman, United Arab Emirates, Sudan, Niger, Chad, India and Pakistan. It’s not a coincidence that these countries also register some of the worst air quality readings on Earth.  

The current trajectory puts the world on track for a temperature rise between 2.1°C and 3.9°C by 2100. In a “hothouse” scenario, according to the Centre for the Study of Existential Risk, University of Cambridge, the most vulnerable communities will be the hardest hit in a warming world, exacerbating inequities. Currently, 30 million people live in the "hottest" places on Earth, primarily in the Sahara Desert, the Gulf Coast & the Indian subcontinent; by 2070 around 2 billion people are expected to live in these areas. Extreme heat and the air pollution it causes are shaping up to be the most significant health hazard in this century. 

The large, congested metropolises in developing countries such as Lagos, Cairo, Dubai, Mumbai Jakarta, and others are the most vulnerable to this risk, as they have very high levels of particulate matter (PM2.5) concentration, stemming from the potent mix of high humidity, scorching temperatures, and heavy reliance on personal vehicles. This leads to as many as 8 million premature deaths every year globally, and that tragedy will only grow as the planet warms. We saw this play out in 2020 with disastrous consequences, a year that has been documented by NASA as tying for the hottest on record, and 2023 is shaping up to beat that mark.  

While climate change can negatively impact air quality, supporting natural ecosystems can be a remedy for rising temperatures. Many urban planners in the developing world are finding that one of the quickest and cheapest methods to improve air quality and lower temperatures in urban areas is to increase green coverage. Trees can improve air quality in several ways, including absorbing air pollutants through small openings on their leaves and bark. Trees also provide shade, which reduces the amount of heat absorbed by buildings and pavement, leading to lower temperatures in high-density urban areas. As I learned first-hand in Bangalore walking through Cubbon Park, the simple act of planting trees and providing green cover really does have a dramatic impact on air quality, a benefit which is now quantifiable with emerging technologies. 

Protection from Dirty Air

Aside from supporting natural ecosystems and promoting green spaces in urban areas, several technologies are hitting the market to adapt to rising temperatures and their impact on human health, particularly targeted for disproportionately impacted regions. There are social enterprises producing low-cost air purifiers to tackle air pollution and companies focused on innovative air filtration technologies such as Smart Air and Airlabs. Other startups are focusing on air quality monitoring devices, sensors, software, and analytics for homes, offices, and cities, with a focus on deployment in air pollution hot spots such as Delhi and Beijing. Hong Kong startup Kaiterra is a great example, focusing on air quality solutions to support low-carbon and healthier buildings.

Electrifying Transport 

Urban areas with high traffic volumes create the so-called “heat island effect” causing the concentration of pollutants to be higher than in surrounding rural areas. This is why substantial private and public capital is flowing into start-ups focused on electrifying transport, especially in the developing world. Nairobi is the home base to several start-ups leading the electrification of public transport in Africa, such as BasiGo and OpiBus . India in particular has become a hotbed of VC activity for the electrification of two- and three-wheel transport (the fastest-growing segment in Africa and Asia). Thoughtful innovations poised to make an impact include building the country’s largest EV two-wheeler fast charging network (Ather Energy), manufacturing low-cost e-scooters (Ola Electric), and AI-enabled electric motorcycles (Revolt Motors). Today, EV rickshaws are appearing on the streets of Bangalore, and many more are planned to hit over the next couple years which will be instrumental in enhancing air quality. For example, the social enterprise firm Three Wheels United is using tech-enhanced financing to deploy tens of thousands of electric rickshaws over the next two years, with support from the local government.   

Recent research from the World Bank suggests the economic case for increased e-mobility in low- and middle-income countries is stronger than ever, especially buses, and two and three-wheeler vehicles. Over the next few years, it is likely that further EV price reductions through efficient procurement and technology innovation will make the economics even more appealing and will help large cities in the so-called hot zones reduce their exposure to extreme heat and particulate matter. McKinsey estimates transport currently makes up 10% of Africa’s GHG emissions, and in the six countries that make up around 70% of sub-Saharan Africa’s annual vehicle sales and 45% of the region’s population (South Africa, Kenya, Rwanda, Uganda, Ethiopia, and Nigeria), vehicles are expected to grow from 25 million today to an estimated 58 million by 2040, driven by urbanization and rising incomes. If the world is going to attain its net zero goals by 2050, electrification of mobility in high-growth countries across Africa, Asia, and the Middle East will be essential.

Trees + Tech

In many cities throughout developing regions, extreme air pollution is a matter of life and death. When used together, trees and technology can help cities adapt to the impacts of climate change on urban air quality and human health. Trees act as natural air filters, absorbing harmful pollutants and releasing oxygen. Planting more trees in urban areas will help reduce air pollution and improve air quality, leading to better health outcomes for individuals living in those areas. On the other hand, rapid advancements in technological solutions related to air purification, renewable energy, electrification of transport, data analytics, and telemetry are enabling us to monitor and manage rising global temperatures, especially in urban centers like Bangalore. By combining the benefits of trees with technology, we can create a more sustainable future and mitigate the most negative impacts of air pollution arising from climate change on our health and the environment. 



Rob Kellogg is the founder of the Sathi Fund for Social Innovators, is on faculty at the Watson Institute where he teaches in their flagship accelerator, and is director of innovation at CrowdSolve, a VC-funded platform supporting early-stage climate innovators. Since 2015, Rob has been active in the social entrepreneurship space, having served as an advisor to founders working on ventures addressing the climate crisis. 

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