"Scientists Propose 'Heat Storm' Concept For Mega Heat Waves"
Heat wave
a period of abnormally high temperature over a region compared to the seasonal normal for that place.
Heat storm
a proposed term for a large-scale, long-duration episode of extreme heat lasting months across wide areas.
India has dealt with heat waves for a long time. They are a known weather danger. A heat wave is a period when temperatures are much higher than normal for that time of year in one region. The World Meteorological Organization (WMO) defines a heat wave in this way: 5 or more consecutive days when the maximum temperature stays 5°C above the historical average maximum for that place. In India, heat waves usually start over Rajasthan, Punjab and Haryana. These areas are far from the sea, so they do not get cooler air from the ocean. The heat then spreads toward Uttar Pradesh, Bihar and the eastern coast. Strong, dry north-westerly winds carry this heat. These winds can even block the sea breeze along the Odisha and Andhra Pradesh coast. This creates heat wave conditions there too. On average, these events used to last 4 to 5 days. They covered about 10% of India's landmass. Heat waves are rare south of 13°N latitude. The surrounding sea keeps peninsular India cooler.
Globally, baseline temperatures are rising because of greenhouse gas accumulation. The main gases are carbon dioxide, methane and nitrous oxide. This has made heat waves longer, hotter and more frequent. This is also connected to the Urban Heat Island effect. In this effect, cities stay several degrees warmer than surrounding rural areas. This happens because of concrete surfaces, lost vegetation, and heat released by vehicles and machines. Night-time temperatures are especially affected. Cities release stored daytime heat slowly after dark. Over the decades, short, local heat episodes have started lasting much longer. They now spread over much larger areas. This is the context for the new idea discussed below.
Researchers study hourly global temperature records since 1960. They argue that the word 'heat wave' no longer describes what is actually happening. A heat storm is a new term proposed for an extended, large-scale episode of extreme heat. It can stretch across huge parts of the globe. It can last for months rather than days. A heat wave once meant a short, local hot spell. A heat storm behaves more like a slow-moving, long-duration weather system. It is similar in scale (though not in physical mechanism) to a cyclone or a monsoon. These are far bigger events than a single rain shower.
A related idea is the heat cascade. …
As per the World Meteorological Organization (WMO), a heat wave is declared when the maximum temperature exceeds the historical average by at least how many degrees Celsius, for how many consecutive days?
Consider the following statements regarding heat waves in India:
1.Heat waves typically originate over Rajasthan, Punjab and Haryana.
2.Heat waves are common south of 13°N latitude due to high humidity.
3.Widespread heat waves normally cover about 10% of India's landmass.
Which of the statements given above is/are correct?
With reference to the recently discussed concept of a 'heat storm', consider the following statements:
1.It describes a large-scale, long-duration episode of extreme heat lasting months.
2.The average duration of such extreme heat events has decreased since the 1960s.
3.The largest recorded heat storm covered about 85% of the globe.
Which of the statements given above is/are correct?
The Urban Heat Island effect, often linked with worsening heat wave impacts, is primarily caused by which of the following factors?
1.Absorption and re-radiation of solar energy by concrete and asphalt
2.Reduced vegetation limiting evaporative cooling
3.Waste heat from vehicles, industry and air conditioners
Select the correct answer using the code given below:
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