Heatwaves: Meaning and Causes

Very similar to blizzards, heatwaves are also complex and fatal winds that affect flora and fauna on large scale. However, in comparison to the blizzard, heatwaves are totally opposite in nature. Blizzard can be seen in temperate region during the winter time; whereas, heatwaves can be seen tropical and sub-tropical region during the summer. In blizzard, temperature always used to be much below to 00 C; on the contrary, in heatwaves, temperature remains 400+. Moreover, one is cold and other one is hot, but both are dangerous for humans and humans’ activities.

What is Heatwave?

As defined by the Intergovernmental Panel on Climate Change (IPCC):

"a period of abnormally hot weather, often defined with reference to a relative temperature threshold, lasting from two days to months."

It means, heatwaves are the phenomena that can be persist for longer period of time for a few days to several weeks, especially during the summer season. During the heatwaves, weather extremely hot and unbearable. Temperature remains unexpectedly high. Extremely hot winds keep blowing and affecting everything that comes into its path.

Causes of Heatwave

During the summer season, heatwave is the product of complex interactions among the immediate atmospheric conditions, local weather system, and incoming solar radiation.

However, some of significant factors that form heatwave are:

• High Pressure System − In a given region, feasibly, high-pressure system stalls over a region for longer period that traps hot air, and likewise, prevent the usual movement of weather system.

• Atmospheric Blocking Patterns − Because of hold of high pressure system at one place for longer period, some of the natural phenomena get disrupted and create ideal condition to develop heatwaves.

• Urban Heat Island Effect − Urban areas, which is also known as concrete mountains because of high rising concrete buildings, trap heats. In addition to this, the various systems and machine (especially air conditioners) used in urban areas generate additional heat. All these human activities create ideal condition for the formation of heatwaves.

• Human Activities − There are various human activities such industrial pollution, use of fire (burning fossil fuels), forest fire (may be human generated or natural), etc., are significant factors that fuel heatwaves in the region.

• Climate Change − Climate change and global warming, which is a longer impact on the pattern of global weather systems, is a prominent cause of heatwave generation.

Impacts of Heatwaves

Heatwaves have several impacts on humans in particular and on nature in general; some of the direct impacts are:

• Human Health − Direct exposure to heatwaves immediately and badly affect the human health, especially to the vulnerable people such as old aged people, young children, and to those people who have already having some health issues. However, heatstroke and dehydration are the common issues during the heatwaves.

• Agriculture and Farming − Prolonged heatwaves substantially damage crops and other farming activities, which reduce the agricultural yields and also affect livestock. It may also cause drought, which ultimately lead to food shortage and increase in food prices.

• Infrastructure and Energy − Prolonged heatwaves exert excessive burden on various infrastructure system, especially energy system. Subsequently, increased the demand for cooling can overload power grids that directly affect the energy or power shortage and infrastructure.

• Ecosystems and Wildlife − In the ecosystem, every organism has their own capacity to bear the temperature difference, but when it goes out of bearable range, it disrupts the wildlife and ultimately the ecosystems.

Safety Measures and Strategies

To mitigate the challenges posed by heatwaves, following are some of the pre-cautionary steps and strategies that one should take care:

• Public Awareness − First of all, having knowledge of heatwaves, is the most essential pre-cautionary step, as without knowledge no one will take any safety measure. Therefore, it is necessary to provide proper guidance on protective measures to individuals as well as communities.

• Early Warning System − There should be an instrument or early warning system that can detect and warn people in advance so that people can take precaution to reduce the heatwave impacts.

• Urban Planning and Green Spaces − Urban planning and architect is one of the safety measures that can potential reduce the impact of heatwaves. The incorporation of various green space, shade, cool roofs, parks, greenery zone along with roads, etc., can reduce the urban heat island effect and ultimately reduce heatwaves impacts especially in cities.

• Reducing Greenhouse Gasses Emission − Greenhouses gases are catalysts for the global warming and global warming means increase in average temperature. Increase in temperature may directly foment heatwaves formation; therefore, it is very important to reduce the use of greenhouse gases.

Conclusion

In tropical and sub-tropical region, heatwaves are unavoidable natural phenomena during the summer season. Its impacts are pretty dangerous and alarming for human beings in particular and the entire ecosystem in general. Therefore, to mitigate the impact of heatwaves, it is important to aware people and guide them to take pre-cautionary step, especially during the heatwaves time.

Frequently Asked Questions

What is a heatwave, and how is it defined meteorologically?

A heatwave is a prolonged period of unusually hot weather, typically lasting several days or more, with temperatures significantly higher than the long-term average for a specific region. Meteorologically, it is defined based on specific thresholds of temperature and duration.

How do heatwaves differ from regular hot weather during the summer months?

While both heatwaves and regular hot weather occur during the summer months, heatwaves are characterized by their exceptional intensity, prolonged duration, and deviation from the usual temperature patterns. Heatwaves often result in record-breaking temperatures and persist for days to weeks, impacting various aspects of life.

What are the health risks associated with heatwaves, and who is most vulnerable?

Heatwaves pose significant health risks, particularly to vulnerable populations such as the elderly, young children, pregnant women, and individuals with pre-existing medical conditions. Heat-related illnesses like heatstroke, heat exhaustion, and dehydration are common during extreme heat events.

How do heatwaves impact the environment and ecosystems?

Heatwaves can have adverse effects on ecosystems and wildlife. Prolonged heat and drought conditions can lead to wildfires, damage vegetation, and disrupt wildlife habitats. Aquatic ecosystems may also suffer from reduced water levels and increased water temperatures.

How do heatwaves affect urban areas, and what is the urban heat island effect?

Heatwaves have a more pronounced impact on urban areas due to the urban heat island effect. This effect refers to the higher temperatures experienced in cities compared to surrounding rural areas, primarily caused by human activities and the extensive use of heat-absorbing materials in urban environments.

Are heatwaves influenced by climate change, and how do they relate to global warming?

Yes, heatwaves are influenced by climate change, and there is a strong link between heatwaves and global warming. As the planet warms due to increased greenhouse gas emissions, heatwaves are becoming more frequent, intense, and prolonged.

What are some effective measures to stay safe during a heatwave?

To stay safe during a heatwave, it is essential to stay hydrated, avoid outdoor activities during the hottest hours, seek shade or air-conditioned spaces, and wear light-colored, loose-fitting clothing. Using fans and cool mist sprays can also help alleviate heat stress.

How can communities and governments prepare for and respond to heatwaves?

Communities and governments can prepare for heatwaves by developing heat emergency response plans, establishing cooling centers, implementing early warning systems, and providing public awareness campaigns about heatwave risks and protective measures.

Are there any long-term strategies to mitigate the impacts of heatwaves and combat climate change?

Yes, long-term strategies to mitigate the impacts of heatwaves and combat climate change include transitioning to renewable energy sources, promoting energy efficiency, implementing sustainable urban planning, and reducing greenhouse gas emissions.

Can heatwaves have economic impacts, and how do they affect various sectors, such as agriculture and energy?

Heatwaves can indeed have significant economic impacts. In agriculture, they can lead to crop failures and reduced yields, impacting food prices. In the energy sector, increased cooling demands during heatwaves can strain power grids and lead to energy supply challenges.