31% Earth Land Mass Had Extreme Heatwaves Beyond Statistical Data, Study Says

According to a recent study, 31% of the earth's landmass has already experienced extreme heatwaves that have gone above and beyond the temperatures predicted by statistical data.

Canada's Lytton New Record Heatwave

Canada broke its all-time high-temperature record in the summer of 2021 by almost 5°C, hitting a new high of 49.6°C, exceeding any temperature ever measured in Europe, Spain, or Turkey. The tiny community of Lytton, which is situated in an area that does not normally experience such high temperatures, set this record. That summer, a heatwave hit the Pacific Northwest of the US and Canada, with Lytton as its high point.

Scientists were astounded by this event because, based on statistics, a heatwave should never occur there. To determine which areas are most vulnerable going forward, climate scientists, including Nicholas Leach from The Conversation, looked into whether the Pacific Northwest heatwave was unusual or whether any other places had experienced similarly statistically unlikely events.

Europe's Severe 2003 Heatwave that Killed 70,000

Tracking these outlier heatwaves is important not just because the heatwaves themselves are dangerous but because countries tend to prepare to the level of the most extreme event within collective memory. As a result, an unusual heatwave may prompt policy changes that will lessen the effects of future extreme heat conditions.

In a case study, it is estimated that the severe heatwave in Europe that happened in 2003 resulted in 50,000-70,000 more deaths. Due to management strategies put in place after the 2003 heatwave, despite more intense heatwaves occurring since none have had such a high death toll.

Using Past Statistics

Knowing when another extreme heatwave will occur is one of the most crucial issues when studying these events. This question can be addressed using techniques from the extreme value theory subfield of statistics.

But several recent occurrences, including the recent heatwave in the Pacific Northwest, have called into question the efficacy of this approach and defied the predictions of extreme value theory. Conventional extreme value theory fails to take into account the particular set of physical mechanisms that might not be present in the events described in the historical record, which results in the "breakdown" of statistics.

Implausible heat is everywhere

In the period from 1959 to 2021, 31% of the Earth's land surface experienced statistically improbable heat, according to the researchers, but there was no discernible spatial pattern.

According to Leach's statement in The Conversation, even among these occurrences, the heatwave in the Pacific Northwest stands out.

When examining "large ensemble" data generated by climate models, the researchers came to the same conclusions.

Analysis of regions that have not previously seen particularly extreme events yields the most significant findings in their research.

At Risk Regions

The research group identified regions around the world that, over the previous 60 years, had not been subjected to unusually high temperatures for their expected climate. Soon, these areas are more likely to experience heat waves that set records. They could sustain serious harm if they lacked prior exposure to such extreme events and had less motivation to plan.

It may come as a surprise that these areas are at risk given that they are not typically linked to the effects of extreme heat like India or the Persian Gulf. At-risk areas include, among others, Afghanistan, several Central American nations, and far eastern Russia.

Both Central Europe and several Chinese provinces, including the region around Beijing, seem to be at risk, but because these regions are more developed, they are likely to have plans in place to lessen the worst effects.

Also Read: Top 10 Deadliest Natural Disasters Around the World in 2022

Study Points

The study demonstrates that statistically improbable heatwaves can happen anywhere on Earth, and the researchers remind the public to exercise caution when estimating the "maximum" heatwave that could occur by relying solely on the historical record. Globally, policymakers need to get ready for extreme heat waves that would be unthinkable based on historical data.

The study also identifies several areas where the historical record is not particularly exceptional and is therefore more likely to be broken. These areas have been fortunate thus far, but as a result, they are probably less ready to handle an extreme heat wave soon. These areas must be especially well-prepared for heatwaves that are even more intense than the ones they have already endured, Phys Org reports.

The study by Leach and several colleagues was recently published in the journal Nature Communications.