New Scientist - USA (2022-02-05)

5 February 2022 | New Scientist | 7

News

Hot water

Heatwaves across

the oceans are the

new normal p

Mind the gap

Game theory shows

how people crowd

on trains p

Gene collector

An insect has picked

up useful DNA from

its food p

No more cookies

Google is changing

the way it tracks

web users p

Distant starburst

Supernova remnant

may have been seen

near Milky Way p

SEEN any unseasonably early

daffodils showing their faces yet?

UK spring flowers are opening

nearly a month earlier than they

did before the mid-1980s, due to

climate change.

That is the conclusion of a study

of nearly 420,000 observations

of the first flowering date of 406

plants from a UK citizen science

project called Nature’s Calendar.

It has records dating back to 1753

from gardeners and naturalists,

as well as bodies such as the UK’s

Royal Meteorological Society.

Ulf Büntgen at the University

of Cambridge and his team found

that plants were opening their

flowers 26 days earlier on average

in the years after 1986 than they

did before. They picked that year

as it was the midpoint in the data

set – where they had about the

same number of observations

before and after – because there

were many more recent records

than earlier ones (Proceedings of

the Royal Society B, DOI: 10.1098/

rspb.2021.2456).

The analysis included records

of all plants, whatever time of year

they flower, but most of them

(like the daffodils pictured above)

bloom in spring. “It is likely that

the influence of climate change

will be greater for spring-flowering

plants, where the usual onset of

warmer temperatures that would

trigger flowering starts earlier,”

says a spokesperson for the UK’s

Royal Horticultural Society.

There was a bigger advance

in the dates of the first blooms

for smaller plants, with those

less than 20 centimetres high

flowering an average of 32 days

earlier in the years after 1986

than they had historically.

In any year, flower opening

times were closely correlated

with the average temperature of

the months from January to April.

“If it’s warmer, it’s an earlier onset.

If it’s cooler, it’s a later one,” says

Büntgen. The average maximum

temperature across those four

months rose by 1.1°C, comparing

the period from 1950 to 1986

with the years after 1986.

The shift could hurt insects,

birds and other wildlife that has

evolved to sync with the flowering

of certain plants, says Büntgen.  ❚

Warmer temperatures in the UK due to climate change are triggering

spring flowers to bloom sooner, reports Clare Wilson

Spring comes early

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Climate change

TWO record-breaking

lightning flashes occurred

in 2020, the World

Meteorological Organization

has confirmed.

One of the flashes

occurred in the southern

US in April of that year

and had a length of about

768 kilometres, or the

distance from London

to Hamburg in Germany.

This is 60 kilometres longer

than the previous record

set in Brazil in 2018.

The second flash was

measured in June 2020.

It straddled the Uruguay-

Argentina border, and

lasted for 17 seconds, longer

than any other flash ever

detected (Bulletin of the

American Meteorological

Society, doi.org/hfhh).

The flash that spanned

the southern US would have

been difficult to measure

with conventional ground-

based equipment, so

meteorologists turned

to lightning mappers on

geostationary satellites,

which have a far wider

field of view.

“We have had this type

of lightning-detection and

mapping equipment in orbit

only for a handful of years,

and through it, we are

learning much more,” says

co-author Randall Cerveny

at Arizona State University.

With both flashes

occurring in 2020, it might 

seem to indicate that

lightning is becoming more

extreme, but it could simply

be that improved imaging

capabilities allowed both

records to be broken so

recently. Alex Wilkins (^) ❚
Physics
Lightning records
set in the Americas