Ha Kyung-ja, professor of atmospheric sciences at Pusan National University / Courtesy of Ha Kyung-ja

Korea experienced scorching daytime heat and sleepless tropical nights well into late September.

It was highly unusual, since the reign of deadly heat waves mostly subsides in late August in a country defined by four distinct seasons.

The seemingly one-off, abnormal development many wish to consider an isolated incident, however, is increasingly becoming a reality, according to Ha Kyung-ja, professor of atmospheric sciences at Pusan National University.

The cover of "First Climate Science Lesson" / Capture from internet

"Korea will have to brace for the fierce grip of summer from as early as April to the end of September," she said.

Typically, months of warm, humid monsoon followed by dry heat waves have been limited to July and August.

However, this will no longer be the case, Ha warns, since heat waves are expected to occur earlier and retreat later in the year.

"The Korean Peninsula will have two more humid heat waves every 10 years. This might seem negligible for now, but the problem is the rapid pace of global warming and the resulting longer and more intense heat waves in the years to come."

The full findings were published in a book, "First Climate Science Lesson," co-authored by three dozen scientists.

She was among many authors who sought to fortify knowledge-oriented critical thinking in an age defined by fearmongering through information and misinformation about climate change and infectious diseases.

The 461-page book discusses disaster response, carbon neutrality and renewables from a scientific perspective.

According to the findings of her research team, humid heat waves in Southeast Asia could increase to as many as 122 days every year by the end of the 21st century.

"About a third of a year will become hot and humid. Humidity leads to more intense heat waves, raising overall temperatures. This translates to the Earth's surface being insulated by water vapor at night, causing hotter tropical nights," she said.

Also grim are the environmental implications.

Wildfires in Gangwon Province in the spring of 2022 were hard to control, due to extremely dry soil from higher temperatures.

"An increase in air temperature means that the air can hold more water vapor, which in turn removes moisture from soil. This is why fire spreads uncontrollably when the ground is extremely dry," Ha said.

The social and economic costs will soar as evidenced by previous papers on the link between death rates and temperature rise published in China, she added.

A study found that a 1.5 degrees Celsius increase in temperature was expected to cause between 49 and 67 per million in heat-caused death, up from 32 per million from 1986 to 2005. A 2 degrees Celsius jump would push up the figure to between 59 and 81 per million.

"Limiting temperature rises to 1.5 degrees Celsius from 2 degrees Celsius could save about 27,900 people in China. Even a drop of 0.1 degrees Celsius can make a difference."

According to the International Labour Organization (ILO), heat-related climate impact could incur financial losses of about $2.4 trillion (3.28 trillion won) by 2030.

The report said more than 2 percent of total working hours worldwide is projected to be lost every year by 2030, either because it is too hot to work or because workers have to work at a slower pace.

"In some parts of western Africa, the resulting productivity loss may even reach 5 percent. The ILO said heat stress reduces the ability of businesses to operate during the hottest hours. I absolutely agree with the assessment. We need to achieve carbon neutrality worldwide."