“A third of the world now faces deadly heatwaves as result of climate change: Study shows risks have climbed steadily since 1980, and the number of people in danger will grow to 48% by 2100 even if emissions are drastically reduced” at
theguardian.com/environment/2017/jun/19/a-third-of-the-world-now-faces-deadly-heatwaves-as-result-of-climate-change
Dear Lynn,
Thank you for posting the article. I like to caution folks that even with the best intentions, popular media accounts of science articles often portray the science inaccurately. Thankfully, though it has regrettably been less true in the past, print media has become much better at linking the article they’re publicizing.
Fortunately, the associated paper,
Global risk of deadly heat, is available in full at the link provided.
Summary findings are given in the abstract.
[We] identified a global threshold beyond which daily mean surface air temperature and relative humidity become deadly. Around 30% of the world’s population is currently exposed to climatic conditions exceeding this deadly threshold for at least 20 days a year. By 2100, this percentage is projected to increase to ∼48% under a scenario with drastic reductions of greenhouse gas emissions and ∼74% under a scenario of growing emissions.
More briefly, the population exposed to the authors’ threshold of temperature and humidity for 20 days or more a year is expected to grow from 30 percent to somewhere between 48 percent and 74 percent depending on how CO2 emissions change.
Readers should also note that newly published results, even in high quality journals, should be afforded less weight than results that have had more time to attract critical review.
By 2100, I predict that upwards of 99% of current CAF posters will be dead. I bet my prediction is more reliable than theirs.
Dear uc,
If you’re offering odds …
The US has been reducing CO2 emissions, significantly, but apparently, that’s not good enough …]
Please forgive me for snipping your larger concern from this posting.
While the US has slowed its growth in CO2 emissions, we have not yet begun to reduce them. It’s always difficult to say if actions are good enough. It is more clear, however, that we can do better, and that any reduction, even in the rate of CO2 emissions, will be helpful in limiting the amount of warming we are currently expecting due to our modern reliance on fossil fuels.
Given that global temperatures have hardly moved in nearly 20 years …]
Dear Ender,
While there was a slowing in the rate of surface temperature increases following the El Niño cycle around 1997 that created the record temperatures of 1998, it’s fairly well established that much, and perhaps most of the excess heat was taken up in the Pacific.
With its release in the latest El Niño cycle, we’ve once again returned to record surface temperatures, including the past three years in a row. This El Niño Southern Oscillation (ENSO) works in tandem with the Pacific Decadal Oscillation (PDO) to alternately store and release heat across, well, decades, which is why one should be especially cautious about reading too much into alterations in temperature increase over shorter periods of time.
The facts are that the models have significantly overestimated the amount of warming we have experienced so far in this century, a fact finally getting “official” recognition. This is from a
paper that came out about two days ago:
- We conclude that model overestimation of tropospheric warming in the early twenty-first century is partly due to systematic deficiencies* in some of the post-2000 external forcings used in the model simulations.
Ender
Again, one should be careful about drawing too much from recently published results, and in this case, I suspect the source that publicized this result was less careful than most. If it’s not too much trouble, would you mind letting me know how you came across this paper?
I note this paper is directed toward satellite-derived models, which have proven notoriously difficult to calibrate, naturally enough, as any attempt to measure tropospheric temperatures from beyond the stratosphere is bound to encounter more issues than simply reading the results from surface stations.
That said, satellite-derived models have been greatly improved over the past couple of decades as a result of papers such as this, and the introduction of data from improved satellites launched over the years.
In the meantime, we have the more reliable surface-station derived temperature models, not addressed in this article.
It’s interesting that you chose a non-peer reviewed article in a pay to publish journal and that costs $175 to read. One can only wonder how many scientists will cite such article for any scientific value it may contain.
Dear frobert,
Please allow me to correct you to some extent. The article offered by Ender is both peer-reviewed, and published in a reputable journal. In fact, with an impact factor of nearly 14, it’s considered a highly respected journal.
That said, I heartily agree that our current scientific publishing industry is in great need of repair, as indicated by the absurd prices attached to individual articles. But you’ll find that these articles can be retrieved without cost by speaking to your local librarian about inter-library loan or if it’s convenient, by visiting the relevant department of a local university.
As ever, Jesse
