BBC Knowledge Asia Edition2

APRI

L

MA

Y

JU

N

E

SU

M

M

ER

SPRING SPRIN

G

10.6°C 11.4°C

14.1°C

14.7°C

17.0°C

17.3°C

Horse

(^) ches
tnut
ut
Hawt
horn
Englis
h (^) oak
Bluebell
Red adm
iral (^) bu
ery
p
Orange
(^) tip (^) bu
ery
Swallow
Su
m
m
er
(^) so
lst
ice
(^20)
Ju^
ne
s)
Ash
1
10
30
25
5
15
20
1
10
30
25
5
15
20
1
10
30
25
5
15
Calendar of natural events
Why 2001? We sometimes lack consistent data on
spring events from the years prior to 1999, so 2001 is
often used by scientists as a benchmark for comparison
instead. This is because temperatures that year were
close to the 1961-1990 average for the UK and so fairly
normal by historical standards, though still feel cool
compared to recent years.
1981-2010
1961-1990
Highest daytime temperature
The dates of nature’s calendar are closely linked
to temperature. Climate change means the UK is
experiencing warmer than normal temperatures in
winter and early spring. The red and yellow bars show
the increase UK maximum daytime temperature for
each month between the 30 years to 1990 and the 30
years to 2010.
Definitions of spring
Meteorological spring begins on 1
March and spans the calendar
months March, April and May. This
simple definition makes weather
comparisons between
different years easier.
Astronomical spring
begins on the spring
equinox on 20 March
and ends at the
summer solstice
on 21 June.
Average
1999-2015
2001
Amphibians
Birds
Insects
Plants
first leaf
first flower
DATA SOURCES: WOODLAND TRUST NATURE’S CALENDAR SURVEY, WWW.NATURESCALENDAR.ORG.UK / UK MET OFFICE