China Heatwave Might Have Killed 300,000: CarrZee Extrapolation of Spanish Figures (2)

中國熱浪死亡人數

Opinion by Mathew Carr, CarrZee

Aug. 30-31, 2022 — Before you accuse me of distributing fake news, I’m writing this specifically to generate curiosity in the mainstream media and get better official information/data from China.

China might not be publishing official data because the heatwave hasn’t completely finished (or I might have missed it).

See this story in The Hindu for an overview of the heatwave.

I’m not saying my estimate is fact, I’m trying to show that the China heatwave death story is a seriously important piece of news that needs to be investigated urgently by scientists and media outlets across the world, because who knows where and when the next 80-day-or-so heatwave will be repeated?

I’m keen to be corrected. I’m enthusiastic for my estimate to be proved wrong.

My estimate of about 300,000 heatwave deaths in China in the past two months or so is based on this Spanish data from its July heatwave:

See this section from this China Daily report on Spain’s deadliest summer in 20 years (to be sure the report does not clearly back up its headline):

“According to the latest report of the Carlos III Health Institute’s Daily Mortality Monitoring System (MoMo) on Thursday, the heatwave that lasted in the country [Spain] from July 9 to July 26 with temperatures exceeding 40 degrees Celsius in many places was responsible for 2,223 of the 11,264 deaths registered in July. Last summer, the respective figures were 568 and 2,385.”

My extrapolation to China’s June 13-August heatwaves, which have lasted about 80 days and are ongoing in some regions, is not academically conclusive, and there is big rain forecast through early September.

Still, my maths below is justified for this article to generate more general interest in the story, and to encourage more official disclosure from China, I contend:

China’s population at 1,451 million or so is 31 times Spain’s at 47 million.

The length of China’s heatwave at about 80 days, 4.7 times Spain’s.

2,223 times 31 times 4.7 = 324,000 (rounded).

NOTE these conclusions from this important China heatwave study from earlier this year (emphasis added):

“Health risks of climate change were characterized by rapid
growth, nonlinear spatial–temporal evolution and extremity. The
attributable deaths to heatwaves in China have dramatically
increased in the past four decades, with the rising trends becoming
more apparent in the recent decade but some fluctuations among
individual years. Nationally, the number of annual attribu-
table deaths was 3679 in 1980s but increased to 6619 in 1990s and
11,159 in 2000s. In 2010s, this number increased to an average of
15,500 attributable deaths, of which the year-to-year variability of
extreme weather has notably increased. Taking a 5-year moving
average, it took 2.8 years for every increase of 1000 annual heat-
wave-related deaths from 1980s to 2000s, but just one year for
the same increase to occur in 2010s. Also, the attributable deaths
reached a highest record of 26,486 in 2017, followed by the second
21,219 in 2019 and the third 20,431 in 2013.

…

In conclusion, this research showed that since China’s reform
and opening up, the number of deaths caused by heatwaves has
been increasing rapidly and exhibited strong spatial heterogeneity
across the country, with more attributable deaths in east and cen-
tral China. Increased exposure to heatwaves, population growth
and aging are the main reasons for the temporal increase and spa-
tial variation of attributable deaths in China. Estimating the num-
ber of attributable deaths and decomposing the factors that drive
to spatiotemporal changes over the long term will help decision-
makers fully understand the health hazards of heatwaves and
develop local response policies to reduce the health losses of
increasing heat exposure under climate change while promoting
sustainable development.”