Hotter and More Frequent Heatwaves Are Endangering More Lives than Ever

ON 10/21/2022 AT 10:50 PM

Global heating associated with the climate crisis is now leaving its mark on more of the heavily populated regions of the world, according to a new UN report, and is considered one of the major contributors to suffering and death.

Heatwaves raging across Africa in October 2022

Heatwaves are currently intense and spreading across Africa, as shown in this satellite temperature map for mid-October 2022. Even though it is still just spring, temperatures in many regions in South Africa are currently over 40° C (104°F). By summer the threat to much of the region and Africa as a whole will be even worse. Northern Australia and the north-central parts of South America are also showing up with intense regional heating. Photo: Peter Dynes, via Twitter

That is the conclusion of a new report just released jointly by the United Nations Office for the Coordination of Humanitarian Affairs, the International Federation of Red Cross (IFRC) and Red Crescent Societies, and the Red Cross Red Crescent Climate Centre.

While the relentless global temperature rise of the planet is the signature of the climate crisis, most are not aware of how heat alone – not just its subsidiary effects on fueling more powerful cyclones and hurricanes; drying rivers, lakes and reservoirs; increasing numbers of wildfires; and sea level rise as glaciers and the poles shed their ice forever – is disabling and killing so many.

The study begins by noting that extreme weather and climate-related disasters have killed more than 410,000 people over the last 10 years. It also points out how this also disproportionately affects low-to-middle-income nations, despite that it is the higher-income countries with their heavier fossil fuel consumption which dumps the lion’s share of heat-trapping greenhouse gases.

The “silent killer” among these deaths comes from heatwaves, the report continues, defining those as “periods of time when unusually hot weather becomes hazardous to human health and well-being”.

Since the 1960s the incidence and impacts of heat waves on the planet have grown in direct proportion to the rise in greenhouse gas emissions globally. Among the worst of those recorded were the 1992 heat blast which spread across southern Africa and affected some 10 million people, with high death rates and other health consequences. In the current century, the intense heatwave of 2003 in Continental Europe is understood to have killed some 70,000 people. In 2008, a single eight-day extreme heat event in India caused 3,800 to lose their lives. Two years later, during the well-documented Russian heatwave of 2010 which is generally recognized as the worst on record, 55,000 people died. And in the summer of 2021 the city of Chennai, India, went down in the record books for the deaths of 11 people in a single day just while waiting for heat-related medical care in a hospital with no more room or time for new patients.

Looking at it in another way, data tracked by the IFRC notes that in the ten years between 2010 and 2019 there were 38 major heat wave events

Tracking heat wave incidents and related deaths, 1960-2019.

A map showing major heat wave events and total deaths (circles with numbers) from 1960 through 2019. (From the report "Extreme Heat: Preparing for the heatwaves of the future", published by the United Nations Office for the Coordination of Humanitarian Affairs, the International Federation of Red Cross (IFRC) and Red Crescent Societies, and the Red Cross Red Crescent Climate Centre. Photo: United Nations Office for the Coordination of Humanitairan Affairs

The impact of these high heat events is far-ranging. They can affect availability of lifesaving drinking water, destroy crops and cause irrigation aquifers to evaporate. They also lead to the collapse of energy grids, driven by increased use of fans and air conditioning. It will also contribute to lost working hours, both within buildings and especially for those working outside in agricultural and construction jobs.

Suffering and death associated with heatwaves result from breakdowns in the human body’s natural ability to cool itself and maintain internal organ temperatures. When external temperatures rise about 37° C (98.6° F), as the report explains, the blood actually grows more viscous as well. The body’s response is to drive the heart harder, to force more blood through the capillaries and do something more to cool the body. Ultimately, if temperatures are too high and exposure to those has been for too long, heat stroke and partial or complete organ failure can follow.

Beyond the absolute numbers and deadly nature of the heating events over time, the report also calls out how many of the heatwaves are affecting those less able to take care of themselves and those with the lowest incomes. Part of this derives from that the highest heat is often located close to the equator, a climate characteristic which is expected to worsen as atmospheric effects tied to global heating are expected to disrupt monsoon and other rainfall patterns over the next two decades.

Within individual populations children, the obese, those with difficulty breathing from asthma and related conditions, those with reduced mobility, and the elderly, are often affected far more than young adults who are more able to withstand many health shocks. The United Nations Children’s Fund (UNICEF) estimates that some 820 million children annually are exposed to extreme heat on a regular basis.

Women are also far more affected by the extreme weather pattern of heatwaves than men. Independent studies described in the report note that 64% of those most affected by heat are women. Some of this is directly attributed to childbearing, which puts a high strain on the body by itself both prior to birth and while breastfeeding. In poorer countries, women are often the ones who must go out to gather water and some food for the community, adding to their burdens.

The climate crisis is also making the heatwaves which do happen last longer and carry with them higher temperatures than in the past. According to data summarized in the report courtesy of The Intergovernmental Panel on Climate Change (IPCC), other ways this is manifesting includes that in the future peak temperatures during heatwaves will increase as well as nighttime minimum temperatures are trending up and at faster rates than in the past.

This study does offer some suggestions for how to address the increasing physical harm to the planet of heat waves.

One category is to improve advance warning of coming heatwaves. These kinds of extreme weather events, especially when they first hit, are generally predictable as much as 3 to 10 days before the heat surges hit. Knowing when the temperatures will surge can allow local government bodies and humanitarian assistance bodies to deploy extra water for those most in need, implement approaches to manage the power grid so those most in need can have access, and help ready emergency shelters. The report recommends the implementing of Community-Based Early Warning Systems (CEWS) as a key to providing important regional guidance to protect against the increased temperatures.

Another approach recommended is to roll out specific mitigation protocols for groups such as those who work outside and those most affected by heat because of age and contributory medical conditions mentioned earlier. When a heatwave is predicted, those who work outside can often have work rescheduled and given preferred access to preventive medical care. Emergency water supply and medical treatment facilities can also be put into place before the worst of the heatwaves appear, to make it easier to respond to emergency conditions.

Identification of the most vulnerable in a community in advance of high heat conditions, followed by deployment of solutions to keep them hydrated, cool, and medically cared for by a new category of emergency “first responders”.

Implementation of real-time monitoring of heat wave conditions and more effective community-based communications systems are also recommended by the study.

Designation of existing buildings such as schools, churches, public libraries, movie theaters, and sports arenas as emergency shelters which will be opened to the public in extreme heat situations.

Provide for payment vouchers for the most needy or automatic bill postponement for high power utility use in the case of heat emergencies. This would have to be managed to avoid abuse but the idea is already spreading as a concept.

Although not cited in the study specifically, other solutions are also available to provide a means of adapting to the increased intensity and number of heat wave events. As one example, many towns and cities are beginning to set aside emergency shelter locations in anticipation of high heat events, either by building new shelters or repurposing abandoned buildings such as old shopping centers. Increased use of more water-efficient indoor farming techniques, such as hydroponics and aquaponics, which produce high crop yields while saving as much a 90% of the water required for conventional farming, can make a big difference both to availability of potable water and food security in the presence of high heat. Demanding that construction codes require extensive use of greywater recycling can also help.

In urban centers other approaches are also possible. One approach to eliminating the “heat dome” re-radiation effect in cities which has been used for some time is by moving to highly reflective white paints for roofing and other structures, so that less heat is absorbed by concrete, asphalt and stone structures. Implementing “living” roofs and walkways where plants interweave with conventional paving materials can also reduce heat buildup even while walking. Still another even more innovative idea for managing re-radiated heat was pioneered in the city of Melbourne, Australia, where water pipes were laid down under roadways. The purpose of the water was to cool the roads even in the presence of heavy traffic and hot atmospheric “heat domes”, so as to lower overall ambient temperatures of the surrounding areas.

Increasingly plentiful and dangerous heatwaves are just part of our global future as the climate crisis intensifies. The ultimate solution for dealing with them is to recognize these events are part of our daily life now, and that they cannot be avoided or ignored any longer. Survival and thriving in the decades to come demand our attention, innovation, creativity, and coming together as connected communities, if for no other reason than to minimize the increased health disasters and deaths these heatwaves will bring.

The report, Extreme Heat: Preparing for the heatwaves of the future, published roughly a month before the 27th United Nations Climate Change Conference (COP27), is available for download here.