JAPAN – DAIKIN INDUSTRIES Ltd. surveyed 100 foreign nationals currently residing in Tokyo on the theme of “summer heat in Tokyo” in a questionnaire entitled “The 20th survey of attitudes of modern man towards the Air”.

This survey was conducted over several years to understand the awareness of “air” to the citizens of today. It focuses on the assessment of the air in our everyday environment by people who can often take air quality for granted.

Tokyo was chosen because it will be the host city for the Summer Olympic Games in 2020. A growing interest in the city and increase the number of tourists is expected at this event as well. Foreign tourists are often struck by the summer heat and high humidity of Tokyo in this season.

Tokyo is a famous city for its heat island phenomenon. The statistics showing the number of days with temperatures above 30 ° C (86 ° F) and 35 ° C (95 ° F) have been exceeded several times in Tokyo, but also throughout Japan. The average temperature in Tokyo has indeed increased by at least 3 ° C over the last 100 years. That is why a survey of foreigners visiting Tokyo was conducted to see how they react, what interests them and catches them in the heat of summer in Japan.

The survey this year marking the 20th year of the DAIKIN survey on “awareness and current status for the summer heat in Tokyo” was conducted among foreign nationals who have experienced the summer heat in Tokyo. The results showed that 90% of surveys estimate that “summer in Tokyo is warmer than that experienced in their countries of origin.” However, the investigation gave a surprising result. The respondents were surprised by the summer lifestyle of Japanese who have adapted to the heat and the number of air conditioners installed in urban areas. They have also gradually adapted themselves to the Japanese summer.

The report of the DAIKIN reported observations as a manufacturer of air conditioning equipment. It also includes a description of summers in Tokyo and suggestions on how to spend the summer in the city in comfort by Mr. Ryoko Imamura, a certified meteorologist

The Main Results of the Survey

Is summer in Tokyo the toughest in the world?

About 90% of respondents said that Tokyo is warmer than their country of origin. The average temperature in Tokyo has increased by at least 3 ℃ in the last 100 years and Tokyo has an important place among the capitals of the world for its heat island phenomenon. Based on the increased number of very hot days where the highest temperature exceeds 35 ° C, the nights are stifling because of the fact that the temperature does not drop below 25 ° C. It is probably fair to say that summer in Tokyo can be among the most hardest in the world.

Now what do foreigners think about summer in Tokyo?

DAIKIN asked foreign nationals who have spent a summer in Tokyo: “What do you think of summer in Tokyo?” The results showed that people felt that summer Tokyo is hot. When asked what they think of the summer in Tokyo compared to the one of their countries of origin, 25% reported “unbearably hot”, 44% “warmer”, and 19% “somewhat warmer” from which approximately 90% (88%) responded that “Tokyo is warmer than my home country”.

Despite the fact that there are a number of cities in the Middle East, South East Asia and Africa whose temperature exceeds that of Tokyo, many foreigners think that summers in Tokyo are warmer than those of their country of origin.

The heat island phenomenon: a phenomenon where the temperature of the air in urban areas is higher than in the one surrounding suburban areas. In urban areas, the temperature tends to rise sharply over the summer. This rise is caused by radiant heat from the asphalt and buildings as well as the heat of the exhaust fumes from cars and air conditioners. An increase in the temperature of the day and the increase in the number of sultry nights causes health risks such as heat stroke and a growing discomfort in everyday life. Over the last 100 years the average temperature in Tokyo increased by at least 3 ° C. The average increase in temperature, however, was lower than in Tokyo than for the rest of Japan, about 0.6 ° C less than the worldwide temperature increase, and about 1.6 ° C lower than in New York.

Is it because of the humidity why they feel so hot?

Why do people feel so hot in summer in Tokyo? When foreigners were asked: “In your opinion, what are the reasons that make you feel so hot in summer in Tokyo?” most of the respondents said: “Because of the high humidity.” They clearly show the characteristics of the Japanese climate in which not only the temperature but also humidity rises during the summer due to the humid air blown into the Pacific Ocean. It was followed by “Because of the high temperature (56%)”, “because the majority of the ground is covered with asphalt and concrete (28%),” and “because the temperature does not drop, even during the night (28%)”.

These results correspond to the characteristics of the heat island phenomenon. Urbanisation causes an increase of temperature due to the radiant heat of the soil covered with asphalt and concrete. Increased night time temperatures – that do not fall quickly because of the insufficient release of heat absorbed by the soil and buildings – are probably why many foreigners feel so hot in Tokyo.

As humidity increases, the temperature increases significantly and people feel a strong heat. This index called “temperature-humidity index” allows to quantitatively measure the heat and humidity of summer. This index is calculated as a function of temperature and humidity. Tokyo is presumed to have a high index of temperature-humidity compared to other major cities in the world because of its high humidity during the summer.

Depending on the region of origin of surveyed people, those in the Middle East and Africa seem to have particular difficulty in coping with moisture (96% gave an answer ‘Because of the high humidity “). On the other hand, the majority of foreign nationals in Europe said feel the heat due to the fact that the night temperature stays warm (56% gave an answer “Because the temperature does not go down, even during the night”) .Taking into account the temperature, many cities have a similar environment in Tokyo. However, summer in Tokyo can be classified as one of the hardest in the world.

Features of summer in Tokyo by the certified meteorologist Ryoko Imamura

The average temperature in Tokyo has risen by about 3 ° C over the past 100 years. This is partly caused by the heat island phenomenon. Due to the high humidity, in addition to the elevated temperature, the man´s temperature sensitivity is higher than the actual temperature.

In addition, Tokyo has been characterised by high night temperature falls. During the day, the concrete and asphalt absorb solar radiation and the heat of the exhaust gas generated as a result of social activities (which is said to be equivalent to about 10% of solar radiation in the summer), and the heat absorbed is released at night. However, the heat released by the concrete and asphalt is reabsorbed by buildings, preventing the release of heat effectively to cause a temperature drop in a vicious circle.

As a result, the temperature remains warm even during the night than last year (2013). During the day, the lowest temperature is above 30 ° C. The fact that there is no time in the day where you can feel free heat is probably why foreigners feel that summer in Tokyo is warmer than in their country of origin.

Moreover, even in Tokyo, the inner area is becoming warmer than in the coastal zone. In general, it is more difficult as the temperature rises over the sea either on the ground so that it is more difficult for the temperature increase in the coastal zone where sea breezes blow.

Very high temperatures are recorded in some cities in the Kanto region, such as Kumagaya City in Saitama Prefecture. This is due in part to the fact that the air warmed by the heat island phenomenon in the Tokyo metropolitan area is blown towards Kumagaya city by the winds of the sea.

For the same reason, the highest temperature in the Tokyo metropolitan area is often recorded around Nerima. The only way that foreign nationals found to protect themselves against the Japanese heat is with the use of umbrellas.

When asked if the means used against the heat of summer in Tokyo have surprised them, the most frequently cited responses were “we use parasols (46%)”. Many Japanese women use umbrellas to protect themselves from sunburn and heat, but the results suggest that this practice is not very common abroad. Nearly half said they were surprised by the use of umbrellas.

The second most frequently cited response was “paper fans (37%),” and the third most frequently cited response is “Wear yukata (light summer kimono) (35%)” and “use different products or cooling equipment (35%)”. They were followed by “sprinkling water on the streets (32%)” and “the use of small wind power (32%)”. These results indicate that foreigners are surprised by the different ideas and ways that the Japanese traditionally use to beat the heat. In other words, what seems quite natural for the Japanese to bring freshness seems to be a strange perspective for foreign nationals.

Japanese traditional methods to beat the heat are classified as unexpected by many foreigners. They are surprised by “the use of air conditioners (18%)”. Foreign residents seem surprised by “the use of air conditioners everywhere in Japan”, not only indoors but also inside vehicles, including electric trains. Some also said they “feel in a cold environment because air conditioners are set at a temperature that is too low”.

Japan is different! What surprised foreigners in Tokyo for the summer?

When asked to foreigners: “What surprised you or impressed during your summer in Tokyo?” many said they were surprised to see” Japanese businessmen working without removing their jackets despite the heat”. Meanwhile, some said they were deeply impressed by the fact that despite the heat, people wear long gloves that go up on their arms or long sleeves as a measure to prevent sunburn. With regard to products that give off a feeling of freshness, some also were surprised that something unusual, even in the eyes of the Japanese, as “a person wearing a hat with an electric fan”.

When asked to foreigners: “In your language, is there a single phrase that describes the heat?” the following expressions were given as answers. We can see there are many ways to describe or express the heat depending on the region, language and culture. Unique expressions of heat:

– Hotter than Hades. (USA)
– So hot you can fry an egg on the ground. (USA)
– A sparrow falls from the roof because of the heat (Netherlands)
– Hot like a steaming pot (South Korea)
– Unbearably hot as grilled on a fire like I’m going to melt (Taiwan)
– Hot as in a steam basket (Hong Kong)
– Warm my liver overflows (Thailand)
– I’m sweating like a pig (Czech Republic)
– Hot as an oven (Russia)

Is there a difference in the use of air conditioners between Japanese and foreign nationals?

When survey respondents were asked: “Do you use an air conditioner at home in your country and in Japan?” 56% said they “use (air conditioning) at home in their country of origin” and 87% said they “use (air conditioning) at home in Japan.” The results showed that many people interviewed, especially those of European countries, tend not to use an air conditioner at home in their home country and have started using for the first time after coming to Japan.

Regarding the temperature setting, the results showed that “the majority of foreigners set their air conditioners at 24 ° C. The Japanese government recommends a temperature of 28 ° C for air conditioning during the summer, but foreign nationals are used to set their air conditioners at much lower temperatures than recommended. They tend to set their air conditioners at as low a temperature as possible, probably to survive the harsh summer heat in Tokyo.

In a hot and humid environment like Japan, it is particularly important to control the humidity to enjoy a comfortable indoor air. It is possible to feel cooler without lowering the set temperature of the air conditioning. It is possible to reduce the moisture dehumidification or creat drafts with electrical and other fans.

Taking into account the current use of air conditioners by region for foreign nationals 72% of those in Europe said they have never used an air conditioner (until they arrive in Japan). Meanwhile, the results showed that the percentage of those who have never used an air conditioner fell 4% when they were asked about the use of air conditioners in Japan. Most foreigners from Europe spend the summer without the aid of an air conditioner because many regions in Europe are relatively cool. However, even those who have never used an air conditioner seem unable to spend the summer in Tokyo without using air-conditioning equipment.

Among foreign nationals from the Middle East or Africa, 52% said they use air conditioners in their country of origin. However, this percentage increased to 100% after their arrival in Japan. As 96% of the Middle East and Africa cited “high humidity” as the reason why they feel so hot summer in Tokyo, the air conditioners are likely for them to cope with the heat and humidity of the city.

One in two foreign nationals is not sure of being able to watch the Tokyo Olympics outdoors.

The Tokyo Olympic Games will be held in 2020 (scheduled from 24 July to 9 August). Interest in Tokyo will undoubtedly increase over the next six years until the summer Olympics. Since this event is held in high summer, we asked respondents whether they would be able to withstand the heat by watching outdoor sports played in the middle of summer in Tokyo.

54% answered “No (I will not be able).” As expected, those who experienced the harsh summers in Tokyo seem to have trouble with having the ability to watch the games while enduring the heat of summer. As Tokyo is a harsh environment to watch the outdoor games, we asked respondents if they could suggest services for sites and cities to beat the heat. The most cited services are “areas where we can avoid direct sun or resting areas such as those with fountains”, “areas where one can feel cool” and “distribution of cold drinks and products to refresh people.”

The primary responses:
– The air-conditioned stands for spectators; large fans for outdoor use that can create drafts
– Fogging systems to cool the air, public fountains
– Provision of ice cream and crushed ice
– Automatic paper caps distributors for fans
– Shaded areas; sunglasses; women’s clothes made of unique materials costs in Japan in suitable sizes to nationals of Western countries.

Advice on how to fight the heat for those who have experienced the summer in Tokyo for the Olympians and spectators / tourists from the same country

We asked respondents whether they have advice on how to fight against the heat of Olympic athletes and spectators / tourists as someone who has lived a summer in Tokyo. They cited most often advice on adequate hydration, such as “drink water constantly, even if you’re not thirsty” and “take with you as many drinks as possible.

The advice seemed to be based on their own experience, because there were some respondents who suffered from heat stroke and dehydration during the summer in Tokyo. There were also those who gave advice on what the Japanese often to beat the heat, such as using umbrellas and products that give off a feeling of freshness. They probably learned and adapted the Japanese unique methods to cope with the summer heat of the country. Regarding the methods for dealing with great heat, they adapt very well to the Japanese culture while to overcome the Japanese summer.

Due to the high humidity in the summer in Tokyo, sometimes we sweat more than usual. This environment different from their country of origin is why foreigners often fall ill. Therefore, it is extremely important to constantly hydrate and rest in a cool place where the temperature is lower. We hope you will be able to enjoy the summer in Tokyo by taking care of your physical condition.

Features of summer in Tokyo by the certified meteorologist Ryoko Imamura

The weather forecast in Japan is very specific and provides detailed information to the rest of the world. In recent years, there have been a growing number of short localized showers in Tokyo called “guerrilla rain”. They are caused by sudden heating of the air and part of the heat island phenomenon.

However, many appropriate measures are provided to deal with this abnormal weather. When you go out, it is advisable to check the weather forecast for the area where you live and for the area you are going for the day to take the necessary precautions.

In addition, some data suggests that the incidence of heat stroke increases day after a stifling night and lack of sleep gradually have a negative impact on his health. Staying indoors, it is recommended to take enough care of the physical condition by controlling the room temperature using air conditioners or similar equipment.