FutureProof is a collaboration between HuffPost and Unearthed , Greenpeace UKs journalism unit

When the summer heat pounds his city, Kumar Manish sleeps out on his balcony to take refuge from the stifling temperatures indoors. Temperatures in the western Indian city of Ahmedabad regularly top 100 degrees Fahrenheit, and people often joke that there are only three kinds of weather here: hot, hotter and hottest.

Ahmedabad heat in peak summer season feels like you are sitting in a furnace, said the 37-year-old communications and social media strategist, who has lived and worked in the city for 14 years. Even basic tasks turn into endurance tests. On a hot day, Manishs short motorcycle trips around the city take twice as long as usual, punctuated by stops at roadside sugarcane stands to rehydrate and take shelter from the punishing sun.

The city of roughly 8 million people has long been familiar with heat. But, exacerbated by climate change, its historically hot summers have been turning into something much more extreme. In 2010, a devastating heat wave sent temperatures soaring to over 116 degrees Fahrenheit (47 degrees Celsius). Medical facilities were inundated with patients struggling from heat-related conditions. A public hospital serving some of the poorest residents in the city reported a surge in admissions of newborns to intensive care due to the searing heat. More than 1,300 people died.

As the climate crisis deepens, temperatures are rising. Extreme heat is one of the deadliest and most pernicious consequences of climate change. And cities home to more than half the worlds population are uniquely vulnerable thanks to a phenomenon called the urban heat island effect . Dark roads and pavements absorb heat, tall buildings cause air to stagnate, and road traffic and industrial activity spew out heat and dangerous amounts of greenhouse gas emissions.

Much like a pandemic, when a heat wave hits a city, it doesnt just kill people its rippling effects wreak havoc across society, straining health services, causing power outages, buckling railways, decreasing worker productivity, and causing intimate partner violence to spike. And those overlapping consequences dont fall equally. Again, like a pandemic, heat finds and exacerbates inequalities already baked into the physical and social infrastructure of a city, hitting low-income neighborhoods and people of color the hardest.

The last five years have been the hottest recorded , and 2020 could be hotter still. Every year, as heat records are smashed, cities swelter and people suffer.

As cities grow over the coming decades, the stakes will get higher: By 2050, 2 in 3 people on Earth will live in an urban area. The solutions boil down to tackling climate change, slashing emissions and halting reliance on fossil fuels. But the pace of international action runs glacially slow, and the impacts of the climate crisis are here, right now. Cities everywhere need to adapt, fast.

Ahmedabad is just one of thousands of cities facing this formidable challenge but it has a plan.

The devastating loss of life in Ahmedabads 2010 heat wave led to a reckoning in the city. No one should be dying from extreme heat. It is entirely preventable, said Anjali Jaiswal, senior director at the Natural Resources Defense Council, India, one of the organizations that partnered with the city government to devise a response.

The largest city in the state of Gujarat, Ahmedabad is one of Indias fastest-growing cities . Migration from neighboring states and abroad is on the rise, with many coming to the city for temporary construction work. The rapidly expanding metropolis has as many as 50,000 construction workers, whose poorly paid, poorly regulated outdoor labor puts them at high risk of heatstroke, exhaustion and other dangerous health problems. And around 900,000 people live in Ahmedabads crowded, heat-vulnerable slum communities.

Any plan to minimize the effects of heat has to include those most at risk. You need to stay hydrated and stay in a cool place to seek medical attention, but you need to get that fast. And so what we did was create a system that supports that, and a system that really focuses on the most vulnerable communities, said Jaiswal.

Ahmedabads heat action plan , the first version of which was published in 2013, concentrated on four key areas: community outreach through news outlets and social media like WhatsApp; early-warning systems; special training for health care professionals; and preventive measures such as installing drinking water stations in the citys slums, opening up temples, mosques and libraries as cooling centers, and providing ice packs to outdoor workers.

And it worked. Five years after the 2010 heat wave, when a similar heat wave swept across India, killing thousands, Ahmedabad had fewer than 20 fatalities .

And while residents like Manish are still forced to find innovative ways to make the heat bearable, at least the city is now prepared.

Ahmedabad has since been hailed as a model for heat resilience. This has really been a community-based program with city residents, businesses all working together to protect the community from extreme heat, said Jaiswal.

Building up social resilience is an aspect of climate preparedness that sometimes doesnt get as much airplay, said Priya Mulgaonkar, resiliency planner for the New York City Environmental Justice Alliance .

Community-focused social measures like those in Ahmedabad may not look as impressive as headline-grabbing cooling schemes like soaring vertical gardens on skyscrapers, but Mulgaonkar says they are one of the easiest, most affordable and most effective ways to keep vulnerable communities safe in a heat emergency. Its not glossy and futuristic, but it works.

These lower-profile but crucial fixes are not unique to India; 7,500 miles west of Ahmedabad, a similar project is being piloted in New York City.

Residents of the Bronx suffer more heat-related illnesses, hospitalization and mortality than those in New York Citys other boroughs. Only a few miles from the northern tip of Manhattans Central Park, where luxury apartments, upscale shops and trees neatly line busy 5th Avenue, the predominantly low-income Black and brown South Bronx neighborhood of Hunts Point is acutely affected by extreme heat.

Our location makes us very unique in our experience of heat even compared to other parts of the South Bronx, because its an urban heat island hot spot, said Dariella Rodriguez, director of community development for The Point Community Development Corporation , known as The Point CDC, a nonprofit that raises awareness about environmental hazards in the South Bronx.

Heavy industry such as waste transfer stations, power plants and high concentrations of truck traffic contribute to Hunts Points heat vulnerability as does the dearth of trees and parks, which reflects a historical lack of green infrastructure investment in low-income neighborhoods of color across the United States.

But Hunts Points strength is its tight-knit community. In 2018, The Point CDC launched an initiative called the Be A Buddy program in collaboration with the city government. It identifies vulnerable residents elderly people living alone, people with disabilities or people living in low-quality housing, for example whom neighborhood volunteers can reach out to during a heat wave. The program has seen considerable success , according to an NYC-EJA report, with 100 people enrolled and more than 500 people reached during a summer heat wave in 2019.

Be A Buddy started as a program to address heat, but quickly, we realized that these people who are most vulnerable to heat issues are also most vulnerable to other things like the need for food, unemployment, and COVID-19, said Rodriguez. We see [the program] as not just about heat. We see it as a way communities can build and depend on each other, and become the experts in times of emergency.

Social resilience is crucial to protecting cities in a heat wave, but since the urban heat island effect is largely driven by the basic physical fabric of a city, modifying that fabric is another vital way to reduce the human cost of extreme heat.

These can be simple fixes like a change of color. When the 2010 heat wave hit Ahmedabad, the black tar roof of the municipal Shardaben hospital absorbed the suns heat. Underneath this roof, the highest and hottest floor of the hospital housed the maternity ward. The number of newborns requiring intensive care leaped during the heat wave.

When Jaiswal visited the hospital in 2014, the ward had been moved to the ground floor and the roof covered with a white reflective china mosaic to lower indoor temperatures as part of the citys cool roofs program . In a hospital with no air conditioning serving some of the citys poorest residents, these simple modifications to the building and its layout made a significant difference.

Moving the maternity ward was found to have a protective effect , too, and eight more health centers in the city have since installed cool roofs.

White roofs are catching on as one relatively simple response to heat. New York Citys $106 million initiative Cool Neighborhoods NYC of which South Bronxs Be a Buddy program is a part is coating roofs with white reflective paint. On the hottest day of a New York summer, a white roof could be as much as 42 degrees Fahrenheit (23 degrees Celsius) cooler than a typical black roof. In Los Angeles, where more than 10% of the citys land surface is heat-trapping black asphalt, city authorities are installing Californias first white, reflective road coatings. LA aims to cover around 1,500 of its most heat-affected blocks over the next decade.

Cities are also deploying nature-based fixes. Ahmedabad plans to plant half a million trees a year between 2020 and 2025. Trees provide vital shade, with their canopies blocking up to 90% of the suns radiation. On a hot day in some parts of the world, taking shelter under a tree can make the air feel up to 15 degrees Celsius (27 degrees Fahrenheit) cooler on our skin.

In Medelln, Colombia, a network of green corridors interconnected avenues lined with trees and other plants help lower temperatures along some of the citys busiest roads, while also drawing pollutants out of the air and storing carbon.

But since cooling infrastructures effects are largely local, where you put it determines who benefits. In Vancouver, Canada a green city with nearly 25% tree cover and where 92% of its residents live within a five minute walk of green spaces the citys poorest neighborhoods have the least protection and suffer the worst heat.

The same is true in the U.S., where communities of color are three times more likely than white communities to live in nature-deprived places . A 2019 study of 108 American cities found that 94% of historically redlined neighborhoods are consistently hotter than other areas in the same city.

Its a result of the systemic racism exemplified by redlining a government-sanctioned effort to segregate communities of color by refusing to give them housing loans and insurance. Redlining gave birth to unjust legacies, including a lack of trees and green spaces, that still put people of color at greater risk of extreme heat almost a century later.

No matter how technically clever a cooling measure is, if planners fail to deploy it in the right places, the already-stark temperature disparity between deprived and affluent neighborhoods will only worsen.

When it comes to urban solutions, we [need to be] big proponents of green infrastructure equity, and making sure that the co-benefits of things like rain gardens or green roofs are prioritized for historically marginalized communities, Mulgaonkar said.

It matters who gets to design the solutions.

In many cases, the people leading climate action plans in cities dont reflect the demographics of the city, said Robert Bullard, professor of urban planning and environmental policy at Texas Southern University, also known as the father of environmental justice . If were not careful in implementing equitable measures, the most vulnerable will still be the most vulnerable. The most marginalized will still be the most marginalized.