What is a Heat Wave? Tips to Stay Safe During Extreme Heat Events

As global temperatures continue to rise, heat waves are becoming more frequent and intense. So, what is a heat wave, and why does it matter? This blog post will explore what causes heat waves, their effects, and how to stay safe during extreme heat.

What is the definition of a heat wave?

What is a Heat Wave?

A heatwave, sometimes called extreme heat, is a period of exceptionally hot weather. 

It can continue anywhere from a few days to months and occurs when the maximum and minimum temperatures are extremely high for the region. 

The lowest temperature is equally significant as the maximum temperature because colder nights enable the body to recuperate. If the nights are abnormally hot, higher temperatures are achieved earlier in the day and persist longer.

What is heat wave condition?

To be called a heat wave, temperatures must be higher than the historical averages for a certain location.

For instance, a couple of 95-degree summer days in Maine may be deemed a heat wave. Yet, if it is in Death Valley, this condition would be very typical.

Heat wave vs. heat dome

Many people are confused between a heat wave and a heat dome. Look at the info below to understand the differences between these two. You can find out more about a heat dome in the article “What is a heat dome?”

What is a heat dome vs heat wave?

Extreme heat warning vs heat health alert vs heatwave

It is essential to understand the difference between an extreme heat warning, a heat health alert, and a heatwave because each signals a different level of risk and requires specific safety measures. 

Recognizing these distinctions helps individuals, communities, and healthcare systems respond more effectively to rising temperatures and protect vulnerable populations.

Are Heatwaves Linked to Climate Change?

Although heatwaves are a severe weather condition, research indicates that climate change is increasing their likelihood. 

According to the IPCC report, climate change is causing heatwaves to last longer, be more intense, and occur more frequently. Burning fossil fuels emits greenhouse gases like carbon dioxide, which trap more heat in the atmosphere. 

The more emissions created, the more heat is retained, resulting in increased global warming and catastrophic weather occurrences. 

Climate change worsens heat waves

Furthermore, of the 152 extreme-weather attribution studies conducted by experts worldwide over the last two decades, 93% determined that human-caused climate change increased the likelihood or severity of extreme heat occurrences.

In fact, climate change has increased the likelihood of the June 2024 heatwave in the United States, Mexico, and Central America by 35 times and raised the temperature by 1.4°C.

What Causes the Heat Wave?

Heatwaves are largely formed by high-pressure systems trapping warm air in one region, preventing it from dispersing.

These high-pressure systems, also called anticyclones, develop a dome of heat by pushing air to sink and compress, raising surface temperatures. 

How a heat wave forms

In addition, the lack of cloud cover under these high-pressure systems enables more solar radiation, which heats the ground and the air above it. 

This combination of elements can lead to extended periods of extremely high temperatures, which can last many days or weeks.

How Do Heat Waves Impact the US and the World?

Heat waves are the hidden killers. Its consequences might be unexpected and life-threatening. 

According to the World Health Organization, heat waves are among the most deadly natural hazards; nonetheless, they receive little attention since their death tolls and devastation are not usually evident. 

Every year, about 500,000 people die from heat-related causes. 

Is a heat wave dangerous?

Climate change has a greater influence on certain places of the world than others. 

For instance, Africa's Sahel witnesses temperatures rising 1.5 times faster than the rest of the world. 

In the Central Sahel (Mali, Burkina Faso, and Niger), 7.5 million people suffer from malnutrition and extreme food insecurity, 2.1 million higher than the previous year.

In the US, heat waves have swept throughout the country, from California to New York, affecting more than 100 million people. Since 1979, almost 14,000 people in the US have died as a result of heat exposure.

How to Stay Safe During a Heat Wave?

Heat waves may harm everyone, especially those over the age of 65, newborns and young children, pregnant women, those with acute or chronic health issues, and socially isolated people.

Therefore, it is crucial to take some heat safety tips to protect yourself. Below are some pieces of advice:

• Use air conditioning if possible

• Drink a lot of water

Stay hydrated

• Wear loose-fitting and light clothing

• Eat light, easy-to-digest foods

• Take a cool bath or shower

• Avoid direct sun exposure…

Find out more hot weather safety tips in our blog to cope and stay safe in extreme heat!

Conclusion

Understanding “what is a heat wave” helps you stay prepared and safe during extreme heat. As these events become more frequent, recognizing the signs and taking action can protect your health and well-being. Take heat advisories immediately to stay safe!