Wednesday 19 July 2017

Extremely Hot Days and Tropical Nights: Keeping Cool during the Fierce Japanese Summer

Weather forecast from the July 9th Yomiuri Shimbun ©
The official end of the rainy season (tsuyu ake =梅雨明け) has just been announced - though, worryingly, we didn't actually have much rain - but already the fiercely hot summer days known as mōshobi (猛暑日) have started. If the temperature reaches 35℃ (95℉) or above it is officially a mōshobi and, rather surprisingly, we have already had a few of these (see left - the high for Tokyo, third line down, on this day, July 9th, has a red rectangle to signal a mōshobi ). Often on such days, the temperature doesn't drop below 25℃ (77℉) - so-called "tropical nights" or nettaiya (熱帯夜) in Japanese - which makes for a double whammy of sweltering heat during the day and a hot, humid, and sticky night.

Heat-stroke counter-measures (Kodaira City Newsletter July 5th)
A key social problem is heat-stroke (necchūshō =熱中症). In the week July 3-9 over 4,000 people - 50% of them elderly - had to be taken to hospital by ambulance (kinkyū hansō =緊急搬送) suffering from heat-stroke. Last year, 50,412 people were carried to hospital in total, 462 were injured and 12 died from heat-stroke. Now local governments are beginning to ramp up their prevention campaign. The leaflet right, for example, lists a number of strategies to prevent heat-stroke including (1) drinking fluids before one gets thirsty, (2) protecting the body from the sun with a hat or parasol, and (3) eating properly.

In sum, everybody is saying that this summer will be a scorcher, perhaps surpassing the agony that was eight consecutive mōshobi days in a row set in August 2015, a new record (2015 had 11  mōshobi in total, just behind the record of 13 set in 2010). While the highest official recorded temperature in Japan is 41℃ (106℉) in Kochi (Shikoku) in August 2013, the unofficial record is 42.7℃ (109℉) in Adachi, Tokyo, in July 2004. In other words, the northern suburbs of Tokyo are among the hottest regions in the country due to their low elevation and long distance from the coast not to mention the heat-island effect. The city's all-time official record high remains 39.5 C (103℉) set on July 20, 2004 - but I wouldn't bet on that not being surpassed this year.

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Luckily, there are lots of traditional ways to cool off in Japan from kakigōri (shaved ice or snow cone - see machine bottom right) and folding or non-folding fans (sensu, pictured bottom left, and uchiwa respectively) to summer kimonos (yukata) and watermelon (suika - pictured left). Even the sound of the summer wind-chime/bell  (fūrin) is supposed to make us feel cooler as it tinkles gently in the breeze. On top of that, summer in Japan is the time for spine-chilling goose-bump inducing ghost stories (right) and haunted houses (obake yashiki) are popular! But assuming one manages to avoid heat-stroke and succeeds in keeping cool it is more difficult to escape the dreaded natsu-bate (夏バテ) or "summer heat fatigue," an affliction that sees many Japanese sink into a lethargic summer funk during the "dog days" of summer. Bate is from the verb bateru meaning exhausted or worn out. Which brings us back to the kanji mō in mōshobi which is the same kanji used in mōken (猛犬) - meaning fierce or savage dog!