By Jungeun Kim, Jennifer Kim and Euan McKirdy, CNN

(CNN) -- As many as 29 people have died due to heatstroke in South Korea, according to the South Korean Ministry of Health, Welfare and Disease Control.

The country is undergoing an extended heatwave, with at least 15 days of temperatures over 35˚C (95˚F) recorded, the Korean Meteorological Administration (KMA) reported. The agency added that Wednesday was the hottest day in Seoul in 111 years, with a temperature of 39.6˚C.

The Office of the Prime Minister has ordered all public construction sites to cease work during daytime hours foe the duration of the extreme temperatures.

The government will also focus on medical support to communities, including providing fluid and cooling systems for 1,000 elderly farmers.

On the northern side of the Korean demilitarized zone, state media KCNA republished an editorial from state newspaper Rodong Sinmun on Thursday, which said "this year's high temperature(s are) an unprecedented natural disaster."

The unprecedented high temperatures are also affecting neighboring Japan, with dozens of deaths reported as temperatures top 41 degrees Celsius.

Last week in Kumagaya, a city near Tokyo, the mercury rose to 41.1 degrees (106 F), the highest ever on record in Japan, according to the Japan Meteorological Agency, almost 12 degrees hotter than average temperatures at this time of year.

Global heatstorm

Much of the northern hemisphere has been experiencing a scorching summer characterized by heatwaves and extreme weather.

Asia has been particularly hard hit. At least 21 people died as a result of flash flooding since July, and more than 190,000 people were relocated in and around Shanghai, where Tropical Storm Ampil is striking the east coast of China.

Hundreds of thousands have also been evacuated from their homes in the Philippines, with monsoon rains exacerbated by multiple storms, causing flooding and other dangers.

It is these types of heatwaves that scientists have been warning would be a consequence of warming the planet through greenhouse gas emissions.

"The impacts of climate change are no longer subtle," said Michael Mann, a climate scientist and director of the Earth System Science Center at Penn State University.

"We are seeing them play out in real time in the form of unprecedented heatwaves, floods, droughts and wildfires. And we've seen them all this summer," he said.

AccuWeather analyst Joel Myers warned that some groups are particularly vulnerable to the high temperatures.

"The elderly and those with pre-existent conditions, such as asthma and heart failure, are likely to face declining health due to exacerbation of their conditions due to weather," he said in a statement.

"Heat exhaustion and stroke, dehydration, migraines, loss of sleep and mood alteration can all occur due to dangerous heat. Historical data shows that more people are likely to be involved in vehicle crashes due to heat-related impacts, such as decreased ability to concentrate, the poor quality of sleep they get and impaired mood, etc."