The day of the year that a plant first blooms is widely considered to be “an important natural indicator of climate change” when observed over the course of decades to centuries.
A new study (Liu et al., 2018) reveals that a flowering plant in Beijing, the Amygdalus davidiana, has not been blooming any earlier in recent decades than it did during the second half of the 18th century.
And when it comes to temperature reconstructions, one geographical region has seemed to receive more attention than any other: China.
Reconstructions of regional China temperatures consistently do not support the position that the modern period falls outside the range of natural variability.
In fact, in the first half of 2018 alone, there have already been 17 scientific papers published documenting a lack of conspicuous modern warming for regional China.
Directly Measuring Temperature/Climate With Blooming Dates
Unlike other temperature proxies used to reconstruct past temperatures, the day of the year a plant or tree blooms can be directly connected to the regional temperature.
Cooler temperatures translate to delayed bloom dates, and warmer temperatures indicate earlier bloom dates.
Compiled over decades to centuries, records of blooming dates can clearly depict long-term climate trends, as demonstrated in Liu and Fang (2017):
In a new study, Liu et al. (2018) obtained records of blooming dates for flowering trees in Beijing during the 260 years between 1741 and 2000. Consistent with many other recent paleoclimate reconstructions for the region,
Liu et al. (2018) did not assess any significant differences between the first blooming dates in the second half of the 18th century (1741-1795) compared to the late 20th century (1963-2000).
In fact, even when including the delayed blooming dates (shown above) during the 1796-1832 period (attributed to that colder period’s higher volcanic activity and lower solar irradiance), the average day-of-year first blooming dates during the 90 years between 1741-1832 were effectively identical to the day-of-year first blooming dates for 1963-2000 (85.2 vs. 84.4).
“No global climate warming due to the greenhouse effect since the Industrial Revolution occurs in the study area” (Li et al., 2009)
As mentioned above, an abundance of proxy reconstructions from the region also show the modern period is no warmer — and even several degrees colder — than it has been for the last several centuries to millennia.
Therefore, it appears to be widely accepted in the scientific literature that China has not been impacted by dangerous or unprecedented “global” warming since the 18th century, or since CO2 concentrations began rising precipitously.
Tories pledge to scrap carbon taxes as industry faces soaring costs, with Sir Jim Ratcliffe backing plans to cut energy bills and boost competitiveness. […]
The day of the year that a plant first blooms is widely considered to be “an important natural indicator of climate change” when observed over the course of decades to centuries.
No mention of evolution.