According to a study conducted by Columbia University's Lamont-Doherty Earth Observatory, an examination of tree rings in western North America has revealed that the heat wave experienced in the summer of 2021 broke records, making it the most extreme in over a thousand years. The research established a chronological record of summer average temperatures dating back to 950 AD. The research shows that the last 40 years have been the warmest ever recorded, and the summer of 2021 was the hottest in more than 1000 years.
The analysis of tree rings and present-day temperature readings reveals that there was a continuous rise in hot summers between 1979 and 2021. The majority of the hottest years were observed after 2000. As per the tree-ring study, the second-warmest period was from 1028 to 1096, called the Medieval Climate Anomaly, which is believed to have caused a natural warming trend affecting several regions of the world. Nevertheless, these earlier periods were much cooler than the temperatures encountered in recent times.
Around 600 old conifers located in northern Idaho and the Cascade ranges of Oregon and Washington were studied by the researchers. They employed a new method called blue intensity to assess the thickness of the tree rings, which can be interpreted as temperature data. According to the findings, the summer of 2021 set a new record for the year, with an average temperature of 66 degrees Fahrenheit, whereas the hottest summer in ancient times occurred in 1080, with an average temperature of 62.4 degrees Fahrenheit.
The study emphasizes how communities that have not previously experienced extreme heat are more susceptible because they lack adequate preparation to handle such circumstances. The researchers propose that setting up safe zones where individuals can seek shelter during future extreme heat waves may be a more viable approach than installing air conditioning systems in all affected areas.
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