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Deadly Japan Heatwave “Due To Global Warming”

May 30, 2019

By Paul Homewood


h/t Robin Guenier



Japan’s heatwave in July 2018 could not have happened without climate change.

That is the unequivocal conclusion of a report released last week, as the country battles yet another record-breaking heatwave.

The July 2018 heatwave, which killed 1,032 people, saw temperatures reach 41.1C, the highest temperature ever recorded in the country. Torrential rains also triggered landslides and the worst flooding in decades.

Penned by the Meteorological Society of Japan, the study is the first to establish that some aspects of the international heatwave could not have occurred in the absence of global warming. Scientists reached this conclusion by employing a technique known as event attribution (EA).

The relatively new method, lead author Yukkiko Imada told Climate Home News, sought to pin down the causality of climate change in the heatwave by simulating 18 climate scenarios with and without the current 1C global warming above pre-industrial levels.

They found a one in five chance of the heatwave occurring in the current climate, but almost no chance of in a climate unchanged by human activity. 

This claim is utterly absurd and dishonest.

As Imada’s study makes abundantly clear, the cause of the heatwave was the coming of two powerful high pressure systems, known as a double-high.

Moreover, two seasonal high-pressure systems, namely the North Pacific subtropical high (NPSH) in the lower troposphere and Tibetan high in the upper troposphere often cause warm climate in Japan (Imada et al. 2014). This two-tiered high-pressure system (double-High) was also visible in July 2018.


The paper goes on to say:

However, experts do not have any  answers on whether the double-High in 2018 was extreme compared to other such  historical events. It is even more difficult to determine the extent to which  human-induced global warming contributed to this event….

Thus, the double-High condition appears to be natural variability  and not affected by the human-induced climate change at this stage.

 In other words, the heatwave would have occurred, regardless of global warming.

As is usually the case with these sort of attribution studies, what this one actually says is that this event was slightly hotter than would have been the case prior to 20thC warming.

It is funny that we never seem to hear about studies that explain how cold winters would have been even colder without AGW!


It is reckoned that 1032 died in the Japan heatwave, but it is certain that many more would have died in pre-industrial versions of that weather event, before the days of air conditioning.

  1. May 30, 2019 2:32 pm

    Seems to me if you monitor 1,000 locations scattered around the globe that on average one of them will have a once in 1,000 year climate event happen, two will have a once in 500 year event happen, and ten will have a once in 100 year event happen just about every year. And those extreme events can be drought, heavy rain, heavy snow, hot temperatures, or cold temperatures for example. A proper scientific analysis must examine huge amounts of data for drawing any conclusions about climatological changes over time for extreme events. The linkage to “global warming” in this article is pure alarmism at its worst as is all too common in the media today because it attracts attention and thus potentially improves revenue. Extreme events like this are quite normal somewhere on the earth every year and are to be expected … it’s just a matter of when, where, and how extreme.

  2. Broadlands permalink
    May 30, 2019 2:35 pm

    Yet another scare-mongering edition with no discussion of what any plausible solution might be. This is the real problem with all those daily global warming alarms. It doesn’t matter how hot or cold, wet or dry it might become if there is nothing realistic these alarmed people can suggest we do about it. What has been suggested is not realism and is impossible…change the Earth’s climate by moving billions of tons of CO2 somewhere.

  3. May 30, 2019 2:53 pm

    ONS: In the 2017 to 2018 winter period, there were an estimated 50,100 excess winter deaths in England and Wales, but who bothers to report it? A bit more warming might help.

  4. Phoenxi44 permalink
    May 30, 2019 2:57 pm

    Even their own conclusions are nonsense. They says there’s a small chance it could have been entirely natural – so there you go. A one-off event that’s unlikely occurring once in thousands of years. Er…..

    The increased chance it happened makes no sense – it happened, so there was in fact a 100% chance it would happen. Unless you can show actual mechanistic causes that mean it would not have happened without those causes you are saying nothing of interest or value whatsoever..

  5. Melting in Tokyo permalink
    May 30, 2019 3:11 pm

    “It is reckoned that 1032 died in the Japan heatwave, but it is certain that many more would have died in pre-industrial versions of that weather event, before the days of air conditioning.”

    While I agree that Man Made global warming is a myth, sadly the quoted statement above may not be correct. The following is from the Japan Times Aug. 06, 2018.

    “A total of 105 people, aged in their 40s to 90s, died from heatstroke in the period from July 1 to Sunday. In 2015, the death toll reached 119.”

    “So far this summer, 99 died indoors. Of them, 55 had air conditioners in their rooms, but 50 of them did not use them. The office found that 33 people had no air conditioners in their rooms.”

    Not all buildings have a/cs in Japan, especially schools. A 6 year old boy died in his school here in Japan last year. His school did not have a/cs. Even when an a/c is in place, the Japanese abhor using them. 50 of the 99 who had a/cs installed yet died indoors did not use them. Every summer is an epic battle between my employers and family to turn on the a/c. But even when used, they are not used so that they can actually do much good. 5 of those who deaths are reported in the article died of heatstroke despite using their a/cs. From 20+years living in Japan, I am as certain as one can be without actually seeing the a/c settings that they were set at 27 Celsius at the lowest temperature, most likely higher, with the fan set at its lowest power setting. It is mind boggling to have adults indoors complain of the a/c set at 28 degrees Celsius being too strong while wearing jackets and sweating.

    Sadly, experienced almost daily during the summer here.

    • May 30, 2019 6:17 pm

      Buildings with little or no ventilation are probably killers, and seem to be on the rise in these days of widespread aircon. I used to work in a building where the windows were CLOSED and the aircon turned on when it got hot, OK if the aircon is working. Prior to that I worked in a sealed building with no aircon, had to sit in the toilets during one heatwave, where it was slightly cooler.

      I greatly value my electric fan at home, for times when the wind dies and the humidity rises, sometimes it gets used all night, otherwise sleep would be difficult.

  6. Curious George permalink
    May 30, 2019 3:40 pm

    I like the exactitude. 1,032 people killed, not 1,031. Where can I find a list?

    • bobn permalink
      May 30, 2019 4:52 pm

      And did they all die of heatstroke? Or does this include heart-attacks, respiratory failures, drownings (I went swimming due to global warming so it killed me because i cant swim). Composition of stats and data needs examining due to the modern trend to exaggeration and false attribution. of course the most notorious falsifying was John Cooks faking of data to get 97%, when the true answer was less than 3.

  7. Curious George permalink
    May 30, 2019 3:42 pm

    Are we back to global warming? I doubt it. Next time somebody freezes to death, it will be climate change.

  8. May 30, 2019 3:47 pm

    Reblogged this on Climate- Science.

  9. May 30, 2019 3:51 pm

    “Climate Change blamed for the deaths of hundreds of puffins” was one of the lead news items on the BBC World Service this morning. I can see no end to this relentless propaganda from what is effectively the broadcast wing of a new religion.

  10. May 30, 2019 4:27 pm

    Reblogged this on Climate Collections.

  11. May 30, 2019 4:59 pm

    Gosh, that’s even worse than a Stott authored extreme weather attribution study. Mind you, at least it’s peer-reviewed. Peter Stott (the pioneer of extreme weather attribution based on fraction of attributable risk calculations) did a Met Office attribution study of the 2018 UK heatwave and found that it was 30% more likely due to climate change – but it was never peer-reviewed even though he presented it as ‘evidence’ of dangerous global warming at Katowice. It’s also never been published. I just cannot get my head around this claim that the heatwave would have been ‘impossible’ without man-made global warming, even though the heatwave is clearly directly attributable to the double-high (natural variability). Bizarre.

    • dave permalink
      May 30, 2019 5:48 pm


      Assertions by persons in the grip of religious mania do tend to be bizarre.

      I always liked the Catholic comedian in America who said that his mother kept various statues of Saints in the house, and prayed to them. If a particular prayer was not answered she would turn the statue upside down, to teach the Saint a lesson.

      “I came home one day and told her I was marrying a Jewish girl. She turned ALL the Saints on their heads!”

  12. I_am_not_a_robot permalink
    May 30, 2019 10:34 pm

    About +3C in the past 100 years is considered to be attributable to the Urban Heat Island Effect by the Tokyo Bureau of Environment:
    That can be seen here:

    Katsuura a small coastal town outside the Tokyo megacity area shows no net warming in 100 years.

  13. Bertie permalink
    May 31, 2019 7:13 am

    This report strikes me as a classic example of the logical fallacy known as ‘begging the question’.
    But, then again, that applies to most of the green blobs increasingly desperate outpourings.

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