UK: plants flower a month earlier under recent warming



by LORENZO CIOTTI

UK: plants flower a month earlier under recent warming

From the UK comes disconcerting news about climate change and the recent heat waves that have hit the planet in 2022. A very recent study, entitled Plants in the UK flower a month earlier under recent warming, and published in the Proceedings.

Biological sciences said it. The study authors said: "Global temperatures are rising at an unprecedented rate, but environmental responses are often difficult to recognize and quantify. Long-term observations of plant phenology, the annually recurring sequence of plant developmental stages, can provide sensitive measures of climate change and important information for ecosystem services.

Here, we present 419 354 recordings of the first flowering date from 406 plant species in the UK between 1753 and 2019 CE.Community-wide first flowering advanced by almost one month on average when comparing all observations before and after 1986.

The mean first flowering time is 6 days earlier in southern than northern sites, 5 days earlier under urban than rural settings, and 1 day earlier at lower than higher elevations. Compared to trees and shrubs, the largest lifeform-specific phenological shift of 32 days is found in herbs, which are generally characterized by fast turnover rates and potentially high level s of genetic adaptation.

Correlated with January-April maximum temperatures at -0.81 from 1952-2019, the observed trends and extremes in the UK's first flowering dataset can affect the functioning and productivity of ecosystems and agriculture." Last summer, the British Met Office said for the first time that the temperature in Britain had reached and exceeded a record 40C.

It is the effect of the powerful heat wave in the UK which has reached its peak after it has already scorched the Iberian Peninsula and France. A phenomenon that may appear exceptional to us, but if observed in the context of the climate crisis it has increasingly normal contours.

The likelihood of a UK heatwave reaching temperatures of 40 degrees was much lower 50 years ago than it is today. In 1971 it was an event that could occur once every 1000 years. In 2022 the probability is once every 86 years.

And the frequency will definitely increase in the future due to the already built-in global warming due to CO2 in the atmosphere. In a high emissions scenario, in 2090 touching 40 degrees will be "exceptional" like a leap year: the frequency will rise to once every 4 years. Every 15 if the COP26 climate promises are met.