“Last 30 years warmest in last 1,400 years” – study

From PAGES 2k Network et al: "Continental-scale temperature reconstructions. 30-year mean temperatures for the seven PAGES 2k Network regions, standardized to have the same mean...North America includes a shorter tree-ring-based and a longer pollen-based reconstruction. Dashed outlines enclose intervals of pronounced volcanic and solar negative forcing since ad 850 (see Methods). The lower panel shows the running count of number of individual proxy records by region." - Source: Mongabay
From PAGES 2k Network et al: “Continental-scale temperature reconstructions. 30-year mean temperatures for the seven PAGES 2k Network regions, standardized to have the same mean…North America includes a shorter tree-ring-based and a longer pollen-based reconstruction. Dashed outlines enclose intervals of pronounced volcanic and solar negative forcing since ad 850 (see Methods). The lower panel shows the running count of number of individual proxy records by region.” – Source: Mongabay

Jeremy Hance reports on 1,400 year climate study for Mongabay.  The report begins:

“From 1971 to 2000, the world’s land areas were the warmest they have been in at least 1,400 years, according to a new study in Nature Geoscience. The massive new study, involving 80 researchers from around the world with the Past Global Changes (PAGES) group, is the first to look at continental temperature changes over two thousand years, providing insights into regional climatic changes from the Roman Empire to the modern day. According to the data, Earth’s land masses were generally cooling until anthropogenic climate change reversed the long-term pattern in the late 19th century.”

Hance reports that this comprehensive study combined data for temperature measurement from, “Tree rings, corals, pollens, sediment, ice cores and stalagmites in caves.”

The study found that temperatures varied from place to place, with continents showing, “Important idiosyncrasies even in the midst of global trends,” according to the report.

Temperature changes occurred during different times on continents,” Hance states.

For instance, the “Medieval Warm Period” occurred 300 years earlier in the North than in the Southern Hemisphere.

The “Little Ice Age” followed this same pattern, reaching the North “decades” before moving into the Southern Hemisphere.

Antarctica was the oddball as the continent, “Bucked trends elsewhere during several periods.”

Hance reports that this well-rounded PAGES study found a decisive global warming trend began in the late 19th century.

According to climatologists,” he writes, “Temperatures have risen about 0.8 degrees Celsius… in the last hundred years due to burning fossil fuels, deforestation, other land-use changes, and industrial agriculture.

Click here to read full report.

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