Atmospheric and Climate Sciences, 2011, 1, 186-188
doi:10.4236/acs.2011.14020 Published Online October 2011 (http://www.SciRP.org/journal/acs)
Changes in Air Temperatures on Mount Fuji, Japan
Noriko Sakano, Nobuyuki Miyatake*, Shoko Murakami
Department of Hygi ene, Faculty of Medicine, Kagawa University, Miki, Kagawa, Japan
Received August 2, 2011; revised September 16, 20 1 1; acce p t ed Septembe r 25, 2011
Abstract
The changes in air temperatures on Mount (Mt.) Fuji, Japan were evaluated. Various parameters of air tem-
peratures on Mt. Fuji in Japan were obtained from Japan Metrological Agency. Parameters of air tempera-
tures were positively correlated with years on Mt. Fuji. In addition, the number of days under –24˚C in Janu-
ary was negatively correlated with years. Global warming was also proved on Mt. Fuji in Japan, especially in
winter. Therefore, we need to deal with global warming effect.
Keywords: Air Temperature, Mount Fuji, Global Warming
1. Introduction
Global average temperatures are predicted to increase by
the end of this century. An increase in mortality related
to heat waves has been reported from various industrial-
ized countries [1]. We have showed that higher air tem-
perature was closely associated with higher ambulance
transports in Takamatsu [2] and Okayama [3] areas, Ja-
pan. In addition, we have also reported that positive
changes in air temperatures were noted in some Japanese
areas [4,5]. However, global warming was not proved at
Showa base in Antarctica. In addition, the number of
days of over 4˚C in January was negatively correlated
with years (r = –0.427, p = 0.0053) [6]. Therefore,
whether an increase in air temperatures is actually in-
creasing in the world remains to be investigated. Mount
(Mt.) Fuji (3775.63 m) is the highest mountain in Japan
and the parameters of air temperatures have been moni-
tored. Therefore, we evaluated the chronological changes
in air temperatures on Mt. Fuji, Japan.
2. Methods
Daily air temperatures at a meteorological observatory
on Mt. Fuji (1965-2009) were obtained from Japan Me-
teorological Agency [7]. A meteorological observatory
on Mt. Fuji is located almost top of the mountain. Mean
air temperature, mean of the highest air temperatures and
mean of the lowest air temperatures in January, August
and a year were used for analysis. Daily data of air tem-
perature in August, 1970 were could not obtain. In addi-
tion, the chan ges in the number of days under variou s air
temperatures in January and those over various air tem-
peratures in August were also used for analysis.
Simple correlation analysis was used to test the sig-
nificance of the linear relationship among continuous
variables: p < 0.05 was considered to be statistically sig-
nificant.
3. Results
Mean air temperature, mean of the highest air tempera-
tures and mean of the lowest a ir temperatures in a year on
Mt. Fuji were significantly correlated with years (mean air
temperature in a year: r = 0.500, p = 0.0005) (Table 1,
Figure 1). From single regression line, estimated positive
change in mean air te mperature in a year for 50 years was
corresponded to 1.3℃ on Mt. Fuji , Japan.
In addition, the relation between years and the number
of days over various air temperatures in August, and be-
tween years and the number of days under various air
temperatures in January were also evaluated. The number
of days of under –24˚C in January was negatively corre-
lated with years (Table 2, Figure 2). However, the num-
ber of days over various air temperatures was not corre-
lated with years in August.
4. Discussion
Although global war ming was not proved at Showa ba se
in Antarctica [6], clinical impact of global warming ef-
fect on Mt. Fuji was noted in this study. Especially, the
number of days under –24˚C in January was significantly
reduced. Bai et al. showed that the number of unusual

187 N. SAKANO ET AL.
Table 1. Relationship between parameters of air temperature and years on Mt. Fuji (1965-2009).
January August Year
r p r p r p
Mean air temperature 0.213 0.1594 0.193 0.2104 0.500 0.0005
Mean of the highest air temperature 0.170 0.2649 0.110 0.4772 0.374 0.0124
Mean of the lowest air temperature 0.229 0.1310 0.259 0.0899 0.381 0.0108
Table 2. Relationship betwee n ye ars and various levels of temperature in January and August on Mt. Fuji.
January August
ｒ ｐ ｒ ｐ
 –21˚C –0.188 0.2163 8˚C

0.064 0.6817
–22˚C –0.192 0.2056 9˚C

0.016 0.9160
 –23˚C –0.272 0.0710 10˚C

–0.113 0.4665
 –24˚C –0.336 0.0239 11˚C

0.008 0.9577
 –25˚C –0.328 0.0276 12˚C

0.064 0.6671
Mean air temperature in a year
˚C
n = 44
r =0.500
p =0.0005
y = 0.026x –57. 541
–8.5
–8
–7.5
–7
–6.5
–6
–5.5
–5
–4.5
1960 1970 19801990 20002010
Yea
r
Figure 1. Simple correlation analysis between mean air
temperature in a year and y ears on Mt. Fuji (1965-2009).
Number of days under -24℃in Januar y
n = 45
r = –0.336
p = 0.0239
y = –0.110x + 228.717
0
2
4
6
8
10
12
14
16
18
20
22
19601970 19801990 20002010
Year
Figure 2 Simple correlation analysis between the number of
days under –24˚C in January and years on Mt. Fuji
(1965-2009).
deaths in the summer of 1994 in Osaka, Japan was more
compared to those of previous years [7]. Qiu et al. also
reported that an unu sually h ot spell in 199 9 was followed
by a high mortality rate in Hokkaido, Japan [8]. The
world may be a very different place today than it was
only a short period ago. Also in Japan, urbanization and
industrialization seems to be accelerated.
In conclusion, in this study, the evidence of global
warming was also proved on Mt. Fuji, especially in win-
ter, which is the highest mountain in Japan. Therefo re, it
seems reasonable to suggest that simply dealing with
global warming effect i.e. innovation of the thermal en-
ergy metabolism in cities and individual coping with
high air temperatures is urgently required in Japan.
5. Acknowledgements
This research was supported in part by Research Grants
from Fukutake Science and Culture Foundation, Japan.
6. References
[1] M. Lye, A. Kamal, “Effects of a Heatwave on Mortal-
ity-Rates in Elderly Inpatients,” Lancet, Vol. 309, No.
8010, 1977, pp. 529-531.
doi:10.1016/S0140-6736(77)91385-X
[2] N. Miyatake, M. Nakao, N. Sakano, S. Suna, T. Suzue
and T. Hirao, “Higher Temperatures Were Closely Asso-
ciated with Higher Ambulance Transports in Takamatsu
Area, Japan,” Journal of Environmental Protection, Vol.
2, No. 1, 2011, pp. 72-75. doi:10.4236/jep.2011.21007
[3] N. Sakano, N. Miyatake, T. Suzue, S. Suna, T. Hirao and
K. Ogino, “The Relation between High Temperatures and
Ambulance Transports in Okayama City, Japan,” Ameri-
can Journal of Preventive Medicine, Vol. 6, No. 1, 2011,
pp. 17-20.
[4] N. Miyatake, N. Sakano, S. Murakami, S. Suna, T. Suzue

N. SAKANO ET AL.
188
and T. Hirao, “Comparison of the Changes in Tempera-
tures among Rural, Urban and Metropolitan Areas around
the Inrand Sea, Japan,” Environ Monit Assess, Vol. 181,
No.1-4, 2011, pp. 525-530.
[5] N. Sakano, N. Miyatake, S. Murakami, T. Suzue, T.
Hirao and K. Ogino, “Changes in Temperatures in Oka-
yama Area Compared with Different Urbanization Areas,
Japan,” Journal of Environmental Protection, Vol. 2, No.
2, 2011, pp. 162-167. doi:10.4236/jep.2011.22018
[6] N. Miyatake, N. Sakano, S. Murakami, T. Suzue and T.
Hirao, “Global Warming Was Not Proved at Showa Base
in Antarctica,” Journal of Environmental Protection, Vol.
2, No. 3, 2011, pp. 323-325. doi:10.4236/jep.2011.23036
[7] Japan Meteorological Agency, 2010.
http://www.data.jma.go.jp/obd/stats/etrn/index
[8] D. Qiu, T. Tanihata, H. Aoyama, T. Fujita, Y. Inaba and
M. Minowa, “Relationship between a High Mortality
Rate and Extreme Heat during the Summer of 1999 in
Hokkaido Prefecture, Japan,” Journal of Epidemiology,
Vol. 12, No. 3, 2002, pp. 254-257.