The World Meteorological Organisation warned in mid-July that the risks associated with the heat wave sweeping the northern hemisphere are not yet over. It also warned of an increased risk of death due to heat waves in Asia, North Africa, and the US.

The intense heat waves this year are worrisome, but they are not surprising because they are in line with expectations as a result of climate change.

One study has indicated that nearly 61,000 people died as a result of high temperatures during heat waves in Europe last year. And it seems that 2023 holds out the prospect of even more terrifying heat that has been made possible as a result of climate change.

As July witnessed record high temperatures in regions of China, the southern US, and southern Europe, millions of people spent days under warnings of the danger of extreme heat. All of Italy, Greece, and Spain have witnessed high temperatures for several days this summer, with possibly more to come. The Italian Ministry of Health issued a red alert for 16 cities.

The current heat wave, dubbed “Cerberus” by the Italian Meteorological Society after the three-headed dog that guards the underworld in ancient Greek mythology, has led to growing concerns for people’s health, especially as it coincides with one of the busiest periods for tourism.

A scientific study concluded that the heat waves that occurred in southern Europe and the US in July would have been “practically impossible” had it not been for climate change related to human activities. Global warming from burning fossil fuels has also increased the probability of heat waves affecting parts of China by a factor of 50.

The study concluded that climate change means that the current heat wave in the southern European countries is some 2.5 degrees Celsius hotter than it would otherwise have been. Experts have warned that almost all societies are not ready to face the extreme heat.

“Heat is among the deadliest types of disaster,” said Julie Arrigi of the Red Cross and Red Crescent Climate Centre, a member of the team overseeing the study. She added that countries should build heat-resistant homes and cooling centres for people to take refuge in during heat waves, as well as find ways to cool cities, including by planting more trees.

Southern Europe is not the only place experiencing extreme temperatures. A dangerous weeks-long heat wave is set to intensify in parts of the western US this month, with more than 90 million people under heat alerts.

The national park in the Californian stretch of the Mojave Desert frequently clocks some of the hottest temperatures on the planet. An official recording by the US National Weather Service found that Death Valley in Nevada was 128 degrees Fahrenheit recently (some 53 degrees Celsius).

As is common in the valley, there were several groups of tourists there to experience the brutal temperatures. A 52-year-old even pulled off a dangerous stunt by running a mile in a Darth Vader getup from the film Star Wars. Another hiker was not so lucky. “Everything is hot here,” a 71-year-old visitor told the Los Angeles Times just hours before his death.

In Las Vegas, 150 miles to the east, residents have been experiencing regular 110-degree days. Passengers passed out in their seats on a plane on the tarmac at the Harry Reid International Airport, and the flight had to be cancelled. In Fire State Park roughly an hour east of Las Vegas, two hikers were found dead on 23 July in the triple digit heat.

INVISIBLE EMERGENCY: Banu Saristo, team leader of the Health Emergencies Unit at the International Federation of Red Cross and Red Crescent Societies, described the heat waves as an “invisible emergency”.

He stressed the need to take care of people who are vulnerable due to their poor health, but also those who face social and economic conditions that “can also cause risks”.

He noted that low-income neighbourhoods in some European cities are currently bearing the brunt of the heat, adding that heat waves are affecting other segments of society “through reduced economic output, stressed health systems, and power outages”.

The World Meteorological Organisation has confirmed that the rise in temperatures is inevitable around the world as a result of climate change, and that it is necessary to prepare and adapt cities, homes, and workplaces to withstand high temperatures for long periods.

It also announced at the beginning of July that global sea surface temperatures had reached a record high in May, June, and July and that a new El Niño warming pattern was just beginning. The El Niño phenomenon is not new, but what is new is the way in which climate change has affected it.

El Niño refers to warm water currents that come from the western Pacific Ocean (Australia) to the eastern Pacific (South America) and extend their peak and then diminish by December. As a result of the spread of warm waters to the east, clouds carrying heavy rains form and may cause flooding in areas affected by the phenomenon.

US scientists have confirmed that the El Niño phenomenon has begun. Experts say that it is likely to make 2024 the hottest year in the world thus far and push the world beyond the stage of warming by 1.5 degrees Celsius, the official goal of the 2015 Paris Climate Agreement.

The phenomenon will affect global weather, which could lead to drought in Australia, more rain in the southern US, and a weakening of the monsoon in India.

Adam Scaife, head of Long-Range Forecasts at the UK Met Office, said that “setting a new global temperature record next year is certainly reasonable. It depends on how big the El Niño phenomenon is. A big El Niño event at the end of this year gives a great chance that we will have a new global temperature record in 2024.”

This natural phenomenon is the strongest fluctuation in the climate system anywhere on Earth.

The El Niño Southern Oscillation, or ENSO, as it is properly called, is known to have three different phases: hot, cold, or neutral. The hot phase, called El Niño, occurs every two to seven years and sees warm waters surface off the coast of South America and spread across the ocean, pumping large amounts of heat into the atmosphere.

Record warm years, including the world’s hottest thus far in 2016, usually occur a year after a strong El Niño event.

Weather agencies around the world use different criteria to decide when this hot phase will come. For scientists in the US, their definition requires that the ocean temperature be 0.5 degrees Celsius warmer than normal for a month, the atmosphere must be observed to respond to this heat, and there must be evidence of the event continuing.

These conditions were met in May. “El Niño conditions exist,” the US National Oceanic and Atmospheric Administration (NOAA) said in a statement.

TRILLIONS AT STAKE: The effects of heat waves are not limited to human costs, but also extend to economic ones as well.

A study by the World Economic Forum has shown that economic growth declines by 0.15 to 0.25 per cent annually for each degree Fahrenheit exceeding normal in a study on the effect of heat highs over US states in the summer.

In general, the global economy loses about $2.4 trillion annually due to heat waves, with the International Labour Organisation estimating that workers lose two per cent of their working hours due to high temperatures, the equivalent to the permanent exit of more than 80 million people from the global workforce. This is likely to increase as the Earth continues to warm.

Estimates by the EU indicate that direct financial losses from high temperatures amounted to 71 billion euros between 1980 and 2000, amid expectations that the costs will be many times greater in the next 20 years due to the fires that have occurred over recent years, especially in 2003 and later, including this year.

The powerful El Niño event of 1997-1998 cost more than $5 trillion, with about 23,000 deaths from storms and floods. There is a strong possibility that this year’s edition will overtake 2024 as the hottest year in the world, a record currently held by 2016.

Global temperatures currently hover around 1.1 degrees Celsius above the global average from 1850 to 1900. But an El Niño event could add as much as 0.2 degrees Celsius to that number, pushing the world into uncharted territory and close to breaking the symbolic 1.5 degrees Celsius barrier of the Paris Climate Agreement.

Both El Niño and La Niña events can also have severe impacts on coral reef ecosystems, especially on corals. Globally, they generated massive bleaching and coral mortality during 1982-1983, 1997-1998, 2002-2003, 2005, and 2010, and contributed to the potential extinctions of coral species.

La Niña refers to the periodic cooling of ocean surface temperatures in the central and east-central equatorial Pacific. La Niña events occur every three to five years or so, but on occasion can occur over successive years. They represent the cool phase of the ENSO.

While there are correlations between widespread coral bleaching in 1997-1998 and the El Niño system, the patterns are not clear. For example, during the 1997-1998 event, bleaching was observed in the eastern Pacific associated with an El Niño event. By contrast, the bleaching in Southeast Asia coincided with the subsequent 1998-1999 La Niña, which brought warm waters to the western Pacific Ocean.

The Indian Ocean bleaching at that time corresponded to warming during El Niño, while bleaching in parts of the Caribbean followed a bleaching pattern typical of the summer following El Niño.

However, large-scale bleaching events do not necessarily occur in conjunction with major El Niño or La Niña events. The largest bleaching event occurred in the Caribbean in 2005, following a mild El Niño event, and was poorly correlated with El Niño climate patterns.

Despite the limitations in knowing how El Niño and La Niña influence coral bleaching events, scientists worry that the increases in global temperatures, and potential increases in El Niño events, threaten the survival of coral reefs worldwide.

In October 2015, the third (and worst) global bleaching event in history was announced to be underway due to a combination of a powerful El Niño and global warming. Scientists said that 93 per cent of the Great Barrier Reef in Australia had bleached by April 2016.

Meanwhile, the Nature Sustainability magazine, part of the prestigious Nature family of magazines, which keeps up with climatic events, has confirmed the findings of the UN Intergovernmental Panel on Climate Change (IPCC) and indicated that exceeding the 1.5 degrees Celsius threshold has become a reality and that the world is heading to reach 2.7 degrees Celsius at the end of the century.

This will mean than a fifth of the world’s population will be exposed to extremely dangerous temperatures that discourage human activity and can result in death, in addition to the damage resulting from the exacerbation of climate change and a succession of natural disasters at an escalating pace.

Forecasts indicate an increase in the average annual temperature from 13 to 25 degrees Celsius, the optimum temperature for humans, to reach 29 degrees Celsius, which means a shrinking of the human climate suitable for habitation and the exercise of human activities, putting two billion people at risk.

In order to avoid this, greater efforts must be made to limit global warming and return to the 1.5 degrees Celsius threshold established in the Paris Climate Agreement in 2015 as the only way to spare three-quarters of the world’s population from exposure to unprecedented temperatures.

Fulfilling the Agreement requires the commitment of the major industrial countries, led by the US, China and India, to reduce greenhouse-gas emissions resulting from industrial activity.

There should also be the activation of the “losses and damages” fund to support affected countries that was agreed on at last year’s UN COP27 Climate Change Conference in Sharm El-Sheikh and the addressing of the effects of climate change on the developing countries, especially those that have not contributed to the global warming process.

The writer is an environmental and climate change expert who works with local and international bodies and has represented Egypt at conferences on the environment and climate abroad.

* A version of this article appears in print in the 3 August, 2023 edition of Al-Ahram Weekly