September 19, 2017 / 7:42 AM
LONDON
(Thomson Reuters Foundation) - When Hurricane Harvey blasted ashore in
August, drowning south Texas in a year’s worth of rain in just a few
days, it left behind an estimated $150 billion in damage to sodden homes
and inundated factories, and claimed about 60 lives.
Two
weeks later, Hurricane Irma churned into Florida, killing at least 33
people there and causing billions more in damages - as well as brutal
loss of life in the Caribbean.
But these storms
may not be 2017’s deadliest U.S. disaster. Instead, that title may go
to a largely unseen killer: rising temperatures.
Over
the last 30 years, increasingly broiling summer heat has claimed more
American lives than flooding, tornadoes or hurricanes, according to the
U.S. National Weather Service.
And the problem
has not been limited to the United States. More than 35,000 people died
during a European heatwave in 2003, and tens of thousands perished in
Russia during extreme heat in 2010.
The threat
is particularly severe in already sweltering places, from South Asia to
the Gulf, and has been linked to a rise in migration out of hot and
poor parts of rural Pakistan.
But experts say
heat remains underestimated as a threat by governments, aid agencies and
individuals. That’s both because it’s an invisible, hard-to-document
disaster that claims lives largely behind closed doors - and because hot
weather just doesn’t strike many people as a serious threat.
“If
you have a natural disaster like a cyclone or an earthquake or a flood,
the impacts are immediate. Things get washed away, people drown. But
heat is a silent killer,” said Sarah Perkins-Kirkpatrick, a climate
change researcher at Australia’s University of New South Wales.
“In
Australia, heatwaves kill more people than any other natural disaster -
but no one realizes the destruction they can cause. The attitude is,
‘It’s hot, suck it up, get on with it’.”
Around
the world, heat is a neglected and poorly understood disaster, in part
because few of the deaths it produces are directly attributed to
heatwaves.
Victims - many elderly, very young,
poor or already unhealthy - often die at home, and not just of heat
stroke but of existing health problems aggravated by heat and
dehydration.
In India, for instance, a major
risk factor for women - who die of heat far more often than men,
researchers say - is the lack of an indoor toilet.
To
avoid embarrassment or harassment, many women refrain from drinking
water during the day to limit their trips to the toilet - a potentially
deadly strategy during heatwaves.
“These deaths
are recorded as normal deaths. But they wouldn’t have happened if it
wasn’t so hot,” said Gulrez Shah Azhar, an Indian heat researcher who
works for the RAND Corporation, a global think tank.
HOTTER CITIES
To
find the true rate of deaths during heatwaves, health officials look at
“excess” deaths - how many more people died than would otherwise be
expected during that period.
In places used to
dealing with hot conditions, there is a “diagnostics failure” in
recognizing the risks of extreme heat, noted Eric Klinenberg, an
American sociologist and expert on a deadly 1995 Chicago heatwave.
In
steamy cities like Miami, “there’s a sense we know how to deal with
heat here, while everybody else is complaining”, he said. “There’s a
will not to see the risk.”
City dwellers, from
Bangkok to Cairo, face particular - and growing - risks. In many rural
areas, trees and open land planted with crops help daytime heat subside
at night, providing some respite.
But in
cities, acres of concrete and asphalt absorb warmth during the day and
radiate it back at night, creating heat islands that can be nearly as
hot at night as during the day.
During
Chicago’s three-day heatwave in 1995, more than 730 people died, many of
them older people living alone and already facing health problems. With
city services overwhelmed, hospitals turned away emergency cases, and
the city’s morgue had to rent refrigerated trucks to store the dead.
With
more than half the world’s population now living in cities - and
two-thirds of people expected to live in them by 2050 - finding ways to
reduce urban heat will be crucial to saving lives as climate change
ramps up heat extremes.
Children cool themselves under misting fans at the Australian Open
tennis tournament at Melbourne Park, Australia, January 21, 2016.
REUTERS/Tyrone Siu
COOLING DOWN
Many
parts of the world, especially those that have already seen substantial
heat deaths, are experimenting with ways to lower the risks.
In
New York, and a host of other cities, authorities are painting roofs
white to reflect more heat and cool inhabitants. They are planting more
trees and preparing hospitals to deal with more heat stroke and other
health problems when temperatures soar.
A
pioneering heat action plan in Ahmedabad, a city in western India, for
instance, automatically triggers deliveries of water to slum areas when
temperatures hit dangerous levels, as well as opening neighborhood
cooling centers.
Simple measures like this are a clear, economical way to save lives, their backers say.
“The
cost of setting up a heat preparedness plan is orders of magnitude
cheaper than the cost of lives. It’s background noise,” said Azhar, who
helped develop the Ahmedabad plan after a 2010 heatwave that killed more
than 1,300 people in the city.
In other
countries, architectural styles designed to deal with heat - often
abandoned when air conditioning became available - are being revived.
Construction
workers, who can’t avoid being outside on hot days, are being kitted
out with gel-filled cooling vests and collars.
Governments
are experimenting with cloud-seeding to bring cooling rain. And some
scientists are already discussing “geoengineering” the planet using sun
shields in space or sulfur particles in the atmosphere to reflect the
sun’s heat.
China,
one of the countries grappling with worsening heatwaves, is trying to
create “sponge cities” with abundant trees and green areas that can
absorb heavy rainfall, then gradually evaporate the cooling moisture
back into the air.
POWER TO THE PEOPLE
In
most hot places, people are advised to stay inside on sweltering days,
drink more water, wear cool clothing and avoid strenuous activity. But
those things can be hard to manage in practice when there’s work to be
done and deadlines to be met.
“I was working at
home on a 45-degree (113-degree Fahrenheit) day, and the guy across the
street was still building a home in that heat,” recalled
Perkins-Kirkpatrick, who lives in Sydney. “There needs to be more
education that it’s not okay to be outside in those conditions.”
In rural areas, as well as many urban ones, lack of access to electricity can be one of the biggest risks during heatwaves.
India
alone has 300 million people without a power connection, which means
they cannot turn on a fan or air conditioning when temperatures soar.
In
New Delhi, some of the poorest of the poor, living on the streets,
sleep near the curb of busy roads at night, hoping to catch a breeze
from passing cars.
When Azhar was growing up in
the Indian city of Lucknow, in a home without electricity, “there was
no escape” from debilitating summer heatwaves. “You’re trapped and there
is literally nothing you can do,” he said.
Experts
say one clear way to reduce growing health risks from heatwaves is to
provide more of the world’s population with access to power,
particularly in the hottest areas.
“The best
way to mitigate (heat deaths) is to get electricity” to run fans or air
conditioning, said Steven J. Davis, a University of California, Irvine
earth system science professor and one of the authors of a 2017 report
that predicted a growing risk of widespread deaths during Indian
heatwaves.
Global efforts, including as part of
the Sustainable Development Goals, to bring power to those without it
could play a significant role in reducing heat deaths, experts say.
But
if action to curb climate change is not robust enough, heatwaves could
more often overwhelm or break down power grids, leaving rich and poor
without help to cool down, they warn.
Tourists at the Jokulsarlon, a glacier lagoon in southern Iceland where
ice bergs breaking off from the Breidamerkurjokull glacier, July 4,
2017. Thomson Reuters Foundation/Thin Lei Win
GAINS AND LOSSES
In
many poor communities, deadly heat is driving innovation. In the slums
of Bhubaneswar, a humid city in eastern India where temperatures last
summer hit 46.8 degrees Celsius (116 degrees Fahrenheit), families have
learned to soak jute sacks in water and place them on their tin roofs,
to cool the inside.
And rickshaw drivers have added wet cooling mats to their vehicle roofs, drawing more customers and boosting their income.
“There
was never a day all this summer that he didn’t bring home 500 rupees
($8)- a third more than others did,” said Kumari Behera, a Bhubaneswar
resident whose son drives one of the “air-conditioned” rickshaws.
Intensifying
heat presents many risks beyond growing loss of life. It is a
contributor to longer and more intense droughts and water shortages that
are destroying harvests and creating more severe forest fires, with
choking smoke.
Higher temperatures can increase
smog production in cities, as heat “cooks” pollution from vehicles, and
extend the length of allergy seasons, prolonging periods of misery for
millions.
And while rising temperatures may
boost harvests in some parts of the world, extreme heat threatens to
slash farm production in many areas, particularly of staple crops such
as wheat, maize, rice and soybeans, scientists say.
In the shorter term, rising temperatures present opportunities for some cooler parts of the world, however.
In
northern Canada, for instance, warmer weather is opening once
frost-prone land to farming for the first time, raising the prospect of
new harvests in new places.
“There’s a lot more
interest in taking a look at underdeveloped land in northern Ontario
and Quebec because of changes in climate,” said Rod Bonnett, president
of the Canadian Federation of Agriculture.
Fishermen
around the world, meanwhile, are finding different species in their
nets, many driven into new waters by ocean warming. Iceland’s fishermen
alone have spotted more than 30 new species in the last two decades, as
some old ones disappear.
“The gains and losses
seem to be balanced for now. But in the long term, I think (the change)
will be slightly positive,” said Hreidar Thor Valtysson, an Icelandic
natural resources specialist, whose children now catch mackerel near the
Arctic Circle.
DISEASE, MIGRATION
Rising
temperatures also look set to change the world’s disease threats.
Mosquitoes that spread potentially deadly viruses from Zika and dengue
to chikungunya thrive better in warmer climates than their
malaria-carrying cousins, researchers at Stanford University found.
That
means malaria rates could fall in some parts of sub-Saharan Africa, for
instance, as temperatures rise and malaria-carrying mosquitoes struggle
- or move to cooler areas of the continent.
But
communities that see malaria diminish likely will face new threats,
including from diseases that are less researched and have lower-funded
eradication efforts.
“We have this intriguing
prospect of the threat of malaria declining in Africa, while Zika,
dengue and chikungunya become more of a danger,” said Erin Mordecai, a
Stanford University professor.
Fiercer heatwaves also are raising questions about the limits of humanity’s ability to adapt.
Christian
Clot, a French-Swiss explorer, has been testing humans’ limits in
extreme conditions, including the nearly 60-degree Celsius (140-degree
Fahrenheit) heat of Iran’s Dasht-e Lut desert.
What
he and doctors have found is that the ability to do just about anything
- including sweat, work and think - diminishes as exposure to extreme
heat grows.
That is a worry with three in four
people in the world expected to face deadly heat by the turn of the
century, according to a study published in the journal Nature.
“We think we’re stronger than nature - but we’re not,” Clot warned.
Researchers believe heat-related migration - already underway - will ramp up.
A
2014 study in Pakistan found that increasing heat - rather than
worsening flooding, as thought - was a strong driver of migration out of
agricultural villages over a 20-year period.
And
in India’s southern state of Tamil Nadu, Vinod Kumar’s family is
already on the move after heat and drought repeatedly wrecked their
crops.
“At this time of year, these fields
should be green with paddy shoots, but no one seems to be farming,” he
said, driving past arid land overgrown with scrub and thorns.
With
too much heat and too little water, “it has become impossible to make a
living from farming”, Kumar said. He now drives a taxi in Chennai to
get by.
Catalan farmers Pau Figueras Mundo (left), 36, and his father Xavier
Figueras Costa, 62, watch over their sheep and goats in a field, in
Jafre, in the northeast region of Girona, Spain, August 9, 2017. Thomson
Reuters Foundation/Lin Taylor
HEAT DAMAGE
Higher
temperatures are also a driver of worsening wildfires that have
scorched woods from Los Angeles to Italy and Canada this year, and
killed more than 60 people in Portugal alone.
In
northeast Spain, farmers spooked by soaring fire risk have moved herds
of goats and sheep into nearby forests to clear underbrush, in an effort
to reduce the chance of runaway blazes.
“We’re very worried,” said Pau Figueras Mundo, a 36-year-old herder, as his animals nibbled at the fringes of a forest.
Paradoxically,
however, it’s the relative lack of obvious damage from most heatwaves
that results in them being underestimated as a threat, experts say.
“Heat
is by no means taken as seriously by governments as hurricanes or
earthquakes or floods. I believe that’s because a lot of our system for
providing relief and assistance is based on property damage,” U.S.
sociologist Klinenberg said.
Extreme heat can
lead to the buckling of roads and railway lines, and reduce the capacity
of power grids. But most of the damage remains “less photogenic” than
other disasters, he said.
Preparing for worsening heat shocks will require planning and broader resilience-building efforts, experts say.
In
Ethiopia, aid agency World Vision has helped rural communities re-grow
felled forests to provide shade, hold more moisture in fields, and give
farmers alternative ways to earn money when drought destroys crops.
“The
more prepared we are for heat stress, the more that communities can
conserve water and change their agricultural practices, (and) the more
they can absorb acute stress,” said Maggie Ibrahim, a resilience manager
with World Vision.
Similar preparation needs to happen in many parts of the world, said Australian heat expert Perkins-Kirkpatrick.
“In
Australia we have heat plans but they’re not very detailed. There needs
to be a national plan and money put into infrastructure - not just
advice like drink water, stay inside and check on your elderly
neighbors,” she said.
That advice is good and necessary, but
“it’s not enough”, she said. Soon “everyone” will be affected, including
people out on a run or mothers walking their kids to school, she added.
INVISIBLE DISASTER
One key problem
in getting heat action plans in place - already a challenge with a
largely invisible disaster threat - is the politics surrounding climate
change.
Heatwaves are the hazard most clearly
tied to global warming. But U.S. President Donald Trump’s Republican-led
administration has denied climate change is a significant risk.
That
has hampered determined efforts by many U.S. cities, states and
companies to prepare for what they see as increasingly evident climate
threats.
Despite an international agreement to
curb climate change reached in Paris in 2015, cuts in the use of fossil
fuels around the world are not yet ambitious enough to meet the
accord’s goal of keeping warming to 1.5 to 2 degrees Celsius above
pre-industrial times.
Instead the world is on a path towards at least 3 to 4 degrees Celsius of warming by the turn of the century, scientists say.
“How
is the global community going to respond to that?” Ibrahim asked. “Are
we just going to accept millions of deaths? We do now around drought,
but will we do that around heat exhaustion? And how are we going to
manage the migration flows?”
“We are not at all prepared globally for the big numbers that will be affected,” she said.
Texas
and Florida, still recovering from Hurricanes Harvey and Irma, may have
particular reason to worry in the years ahead, scientists say.
An
analysis by Climate Central, a U.S. non-profit science and media
organization, found that Houston by 2030 is likely to face “heat danger
days” - when combined heat and humidity make temperatures feel like 105
degrees Fahrenheit (40 degrees Celsius) - 110 days a year.
Miami will face 126 such days each year by 2030, it noted.
“A
one-off every now and then we can recover from,” said
Perkins-Kirkpatrick. “But we’ll be seeing this almost every summer in
the next 40 or 50 years. We need to do something about it.”
Reporting
by Laurie Goering @lauriegoering; editing by Ros Russell and Megan
Rowling; Please credit the Thomson Reuters Foundation, the charitable
arm of Thomson Reuters, that covers humanitarian news, climate change,
resilience, women's rights, trafficking and property rights. Visit news.trust.org/climate
Our Standards:The Thomson Reuters Trust Principles.
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