Scientists have reported that the last 30 years of the 20th century, i.e. from 1971-2000, were the warmest years in the last 14 centuries in the history of the Earth.
Researchers in this study worked on the previous two millennia and found a “long-term cooling trend”, i.e. 0.1-0.3 C (0.2-0.6 F) of cooling per thousand years, depending on the region, until the end of the late 19th century. They found that the temperature of the Earth was 0.4 degrees Celsius (0.7 degrees Fahrenheit) higher in the 20th century than the temperature from the last 500 years with only the exception of Antarctica.
However, this finding is a global average and temperature may vary from one region to another for example Europe was probably warmer in the 1st century AD than at the end of the 20th century.
“There are things that are common to all the regions of the planet — long-term cooling, until the 19th century, followed by warming on all continents, except for Antarctica, where it is less clear, but also strong variations from one region to another,” Hugues Goosse, a climatologist at Belgium’s Catholic University of Leuven, told AFP.
“Distinctive periods, such as the Medieval Warm Period or the Little Ice Age stand out, but do not show a globally uniform pattern on multi-decadal time scales,” said Heinz Wanner of the University of Bern in Switzerland, one of 78 researchers from 24 countries who took part in the project.
This research has limitations as the temperature record for Africa was sparse.
A scientific initiative called the Past Global Changes (PAGES) 2K Network coordinated this research.
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