Hit by heatwaves, cities test fresh ways to cool residents

As fossil fuel emissions creep higher, warming up the planet, they are fuelling harsher, longer and more frequent heatwaves that can kill greater numbers of people.

Parts of India and Pakistan in May saw temperatures hit an unbearable 50 degrees Celsius (122 degrees Fahrenheit) - a spike scientists said was 30 times more likely because of climate change.

This week, heatwaves of well above 100 degrees Fahrenheit (38C) are expected across a wide swathe of the United States - and even normally comfortable London is predicted to top 32 degrees Celsius (90 F) on Friday.

"These temperatures should serve as a dire warning for all of us ... to better prepare to manage dangerous heatwaves," warned Francesco Rocca, president of the International Federation of Red Cross and Red Crescent Societes (IFRC).

But while preparations are lagging globally, experts say, many cities are exploring innovative ideas to keep people safe - from insurance policies that fund preparations ahead of a heatwave to shade canopies that generate solar power.

Here's what you should know about growing heat risk - and how to deal with it:

Often termed "silent killers", heatwaves lead to more deaths each year than any other disaster, health experts say.

But because most of those deaths occur at home, with heat aggravating pre-existing vulnerabilities such as heart disease, they are less visible and often undercounted.

Older people and young children - who have more difficulty regulating their body temperature - are particularly vulnerable, medics say, along with pregnant and breastfeeding women, the disabled and those who must work in hot conditions.

Besides causing fatalities, heatwaves also regularly lead to a higher rate of accidents at work, as people sleep poorly, and contribute to everything from wildfires and crop failures to water and power shortages, which can drive up death rates.

Australia has even seen extreme heat generate thunderstorms full of pollen-laden rain that have led to a surge in asthma deaths, said Amanda Ikert, head of climate adaptation with C40 Cities, a global network of cities working on climate action.

Greece's capital, Athens, is piloting a system to categorise heatwaves by threat level - much like hurricane warnings, said its "chief heat officer" Eleni Myrivili, whose job title is in itself an innovation.

The system uses an algorithm that brings in weather predictions and data from past mortality in heatwaves to give people a clearer idea of the level of risk on any given day, she said, describing it as a "game changer".

In Tokyo, officials are experimenting with wind tunnels to increase airflow in hot areas, while Tel Aviv is installing light-coloured fabric sun shades with solar panels in public squares which generate power to light the areas at night, making them safer and more attractive to use round-the-clock.

Cape Town and Buenos Aires are putting in place light-coloured and other cooling roofs on public housing, while Kuala Lumpur is looking at a "district cooling" system using renewable energy and natural water bodies to pump cooling water to homes.

In some Australian cities, Red Cross workers now make calls to vulnerable people on hot days - and dispatch emergency services if they go unanswered.

Spanish cities, meanwhile, are experimenting with placing ambulances at the beach to handle heatstroke cases there.

Other cities provide grants to low-income families so they can afford to keep fans or air conditioners running.

Broader efforts to shore up basic water and power supply systems - to keep them on during heatwaves and give people the tools they need to stay cooler - are also crucial to saving lives, heat experts say.

Some cities are even exploring efforts to reduce humidity, a huge added risk factor in heatwaves, by planting tree species that absorb more moisture in the air or release less water from their leaves.

While some changes to cut heat risk can be costly, others are cheap and simple, the experts said - such as making messages about what to do in a heatwave accurate and clear.

Urging vulnerable people to go to cooling centres, for instance, makes little sense if they don't have enough space or if they are too far away and users can't get there safely via shaded paths or air-conditioned transport.

For years, governments in countries prone to hurricanes - including many in the Caribbean - have bought insurance policies that provide a fast payout if pre-set thresholds are passed, such as certain wind speeds and rainfall amounts.

This "parametric" insurance can channel quick cash to governments to launch recovery efforts, without waiting for claims adjustors to assess the damage and file reports.

In Africa, a growing number of small-scale farmers are also using comparable policies to quickly deal with crop losses, including from excessive heat and drought.

Now experts are working to create similar heatwave insurance, designed to pay out ahead of time when brutal heat is forecast, giving government policy-holders cash and time to prepare, such as by setting up cooling centres.

"Insurance has a very big role to play" in easing heat risks, said Myrivili of Athens, one of the cities looking at eventually purchasing such policies.

Many parts of the world are only now recognising their vulnerability to heat risks - such as the normally mild U.S. Pacific northwest and Canadian British Columbia, which were shocked by scorching temperatures last summer.

Until a deadly heatwave hits - and sometimes even after - governments can be hesitant to divert money to a problem they're not sure ranks above others they are dealing with, experts said.

Investing in preparations for heatwaves that may only reap benefits once the politicians funding them are out of office can also put some leaders off acting, they added.

As well, creating effective heat action plans requires coordination across different areas of government, from health and transport to parks and building codes, something Ikert called "a challenge".

But the risks of not acting are significant, she and others added - with scientists predicting not just deaths, job losses and other economic harm but potentially protests and unrest.

Cutting climate-changing emissions is also crucial to curbing heat risks, experts said.

Soaring heat in India and Pakistan, for instance, has triggered the reopening of closed coal mines and power plants to meet rising demand, and could drive even higher emissions.

Investing now in renewable power and taming heat risk can help ensure soaring demand for cooling does not fuel even more climate change and deadlier heatwaves globally, experts said.

"These are temperatures ... we cannot adapt to. We have to figure out ways to protect ourselves," said Myrivili of Athens.