Even Evidence From Poems Suggests 1st Millennium China Had Decades 1-2°C Warmer Than Today
Humans have been recording flowering/bloom dates in China for over 1,000 years. These records affirm modern warmth in China is neither unprecedented nor unusual.
Per temperature reconstructions gleaned from phenological records in poems, Central China had multiple 1-2°C warmer decades than 1961-1990 during the 1st millennium (Liu et al., 2021).
Image Source: Liu et al., 2021
Per Liu et al. (2018), the first blooming date of Amygdalus davidiana (FBA) in Beijing from A.D. 1741 to 2000 show there was effectively no temperature differentiation – less than one day (Day 85.2 vs. Day 84.4) for the first blooming date – between the 1741-1832 and 1963-2000 climate periods.
Image Source: Liu et al., 2018 (full paper)
In his 1975 we-must-modify-the-climate-to-stop-global-cooling book, The Genesis Strategy, the late Dr. Stephen Schneider pointed out that cherry blossom first blooming dates had been occurring later and later in the spring for decades, consistent with the contemporary global cooling.
To put these blooming dates and associated climate changes into a larger perspective, humans have been living in China for the last 1.7 to 2.1 million years.
As recently as 8,000 to 10,000 years ago, China was 5 to 9°C warmer than it is today. These temperatures were realized when CO2 concentrations were said to be ranging between 255 to 260 ppm.
Image Source: Zheng et al., 2018
So even though phenological evidence affirms China’s temperatures have undergone tiny changes in the last few centuries (and they were perhaps 1-2°C warmer ~1,200 years ago), there is widespread belief that something climatically unusual is occurring today.