地球環境研究,Vol.11(2009)

Experimental Studies of Meteorological Influences onSkin Moisture in Warm Seasons
FUJITA Yuka＊, FUKUOKA Yoshitaka＊＊
Keywords: facial skin surface, skin surface moisture, statistical analysis
they make efforts to forecast Dry Skin Information.

Purpose of StudyDry Skin Information is computed from minimum

The skin condition is thought to be controlled byand maximum temperature as dry index. It is obvi-

the external environments such as weather conditions

ously understood that when dry condition continues

and others it is researched from the various view-

several days the skin moisture is more decreased andpoint. The clarification of relationship between thethe skin condition becomes worse comparing with theweather and skin conditions could be the fundamental

case of only one day dryness. Then we think that notdata for remedy of some skin diseases, and most of

only concerned day but past weather conditions

researching reports about them are concerning skinshould be considered in order to assess the skin condi-moisture which has severe influences on appearance.

tion accurately. In this study, therefore, we purpose

Lately, many weather companies pay attention toto make clear how the skin is effected by meteorologi-

the relationship between skin and weather so thatcal elements and life history under natural condition.

Fig.1
＊＊＊

Flow Chart of Study

Graduate Student of Geo-environmental Science, Rissho University
Faculty of Geo-environmental Science, Rissho University

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deviation of skin moisture

Experimental Studies of Meteorological Influences on Skin Moisture in Warm Seasons (Fujita, Fukuoka)

Group AGroup B
Group C

accumulative temperature (up to 7 days)
Fig.2

Relationship between accumulative temperature (up to 7 days) and deviation of skin moisture

Kumagaya and examinees outside of Kumagaya when

Study Methods

the relationship between weather and skin conditions

The examinees in this study are twelve healthy

are analyzed statistically. Examinees are divided into

female students of Rissho University who are between

three groups; four examinees with make-up living in

20 and 22 years old. Measurements are carried on at

Kumagaya (Group A), three examinees without

air-conditioned laboratory of Rissho University in

make-up living in Kumagaya (Group B) and five

Kumagaya City, Saitama during April 6 to July 9,examinees with make-up living outside in Kumagaya

2007.

(Group C).

Skin moisture is measured by Derma Unit SSC3
(Cornemeter CM825, Courage+Khazaka Co,), Forehead and cheek are selected as measuring points. On
those points, moisture is measured 2 times per 2
points to get average from 4 values. Those averages
arecompared

Kumagaya Meteorological Observatory, where water

which are not significant, especially in the case of thevapor pressure (Et ) is not observed. We calculate Et

examinees outside of Kumagaya. But as the roughfrom Tetens's formula as follows;

trend it is shown that the air temperature is higher

6.11 x 10f(t)elements

The correlation coefficients between the skin and
air temperature are generally low and at most 0.15,=

meteorological

Air tempereature

at

Et

with

Results of Study…………………………… 

the deviation of skin moisture becomes larger. On theother hand, in the case of the examinees inside ofwhere Et means saturation water vapor pressure at

Kumagaya, the correlation coefficients indicatedtemperature t(℃) and f(t) = 7.5t/(t+237).

somewhat higher positive values, of which the indoor

In order to weight the past life-history, we com-temperature showed the highest positive correlation

puted the accumulative values of those meteorologicalcoefficient 0.31. The mean air temperature and accu-elements, which are obtained for two days from previ-mulative temperature (up to 7 days) are following

ous day to 7 days from a week ago.

and significant (p＜0.05).

7 examinees of 12 are living in Kumagaya City, ofEspecially, the skin moisture of no make-up groupwhich 3 examinees have no make-up. Therefore, allis highly correlated with the accumulative and mean

examinees are classified into three groups; make-up

air temperature, whose correlation coefficients are

examinees in Kumagaya, no make-up ones inmore than 0.50 and significant in p＜0.01 (See Fig.2).

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deviation of skin moisture

地球環境研究,Vol.11(2009)

Group AGroup B
Group C

accumulative water vapor (up to 7 days)
Fig.3

Relationship between accumulative water vapor (up to 7 days) and deviation of skin moisture

Humidity and Water Vapor Pressure
In the case of no make-up examinees the skin moisture has positive correlation coefficients more thanbody. Since the water supplement inside body is notavailable, the skin moisture may be greatly affectedby perspiration and dry atmosphere.

0.3 with minimum and accumulative humidity (6-Perspiration is mainly affected by air temperature.

7days), while in the case of the other groups theIt is reported that when ambient temperature is overcorrelation coefficients are less than 0.1.

22℃ the invisible perspiration occurs and the stratum

There could be found the positive correlation coeffi-corneum moisture increases. Since the higher tem-

cients in the examinees outside of Kumagaya City,

perature brings about visible perspiration it isthat is, the water vapor pressure is higher, the devia-

thought that perspiration increases and deviation oftion of skin moisture is higher. As for the no make-up

skin moisture results to be higher. As Fig.2 shows,examinees in Kumagaya City, the correlation coeffi-

the skin moisture is positively proportional to thecient is highest and significant on all factors.

accumulative temperature especially above 140 (℃・In conclusion, Kumagaya examinees indicate theday). This degree 140 (℃・day) could be calculated

highest correlation coefficient with increasing accu-

into 20 per a day , which is roughly equal to the criti-

mulative days. The case of seven days' accumulated

cal temperature when perspiration occurs. This result

water vapor pressure is expressed in Fig.3.

coincides with the studies by Tagami (2005) andYoshikuni (1983).

Discussion
1. Air Temperature

2. Humidity and Water Vapor Pressure
Even if the humidity is same, the moisture includ-The fact that the correlation coefficient between air

ing in the air differs under the different temperature.

temperature and skin moisture is positive means that

Therefore, the relative humidity can not express thethe perspiration increases with air temperature. The

moisture in the air, which makes the correlation coef-water absorption capacity of stratum corneum relat-

ficients smaller. In short, the water vapor pressure

ing with morphological or functional abnormity, such

shuld be used for taking account of the reloationshipas skin disease, does not change all the year roundbetween air moisture and stratum corneum moisture.

and is higher in summer and winter in the case of face

It is also concluded that two factors bring about

surface. Therefore, the moisture variation occurs due

positive correlation coefficient between skin moisture

to water supplement or dryness inside body or outside

and water vapor pressure as same as air temperature.

197

Experimental Studies of Meteorological Influences on Skin Moisture in Warm Seasons (Fujita, Fukuoka)

Fig.4

Seasonal change of water vapor pressure, humidity and air temperatures

One is the facts that Kumagaya has regular seasonal

Kumagaya City. In this study, the past life-stylechange weather, and that from spring to summer

means that the examinees could be influenced by theboth of water vapor pressure and air temperature are

air condition in bus or electric car and that some ofincreasing as shown in Fig.4. Second one is the effectexaminees powder her face while the other does not. Itof water vapor pressure. According to Sasaki (1982),

could be considered that powder makes her face littleevaporation by the perspiration is proportional to theinfluences by weather conditions.

difference of saturation water vapor pressure in skintemperature and water vapor pressure in ambient air.

References

If the evaporation process on skin surface is almost

Denda,M. (2005): "Skin thinks", Iwanami Co. Japan.

same to that on earth, the evaporation may be calcu-Kagami,M. (1991): "Human-body guessed by weather",lated by the formula as follows.

Kodansya Co.Tokyo, Japan.
Sasaki,T. (1982); "Health and weather", Asakura Co. Tokyo,E=CEU (qS - q)

ρ………………………… Japan.
Tagami,H.

E: evaporation, ρ ;air density, CE ; latent heat transport coefficient, U; wind velocity,
qS; saturation specific humidity, q: specific humidity(1999);"Medicalscienceofskin",

Tyuukoushinsyo, Japan.
Tamura,T. (2000); "Clothing hygienic", Bunkasyuppan,Japan.
Tanaka,M. (1996); "The relation of human and water",

3. Effects of Regional Condition and Life-stile
We could conclude that relation of skin moisture
and weather condition depends upon geographicalconditions, that is, examinees are inside or outside of198

Rikoutosyo, Japan.
Yoshino,M. & Fukuoka,Y. (2002); "Med-weather forecast",
Kodansya Co. Japan.

地球環境研究,Vol.11(2009)

Experimental Studies of Meteorological Influences on
Skin Moisture in Warm Seasons
FUJITA Yuka＊, FUKUOKA Yoshitaka＊＊＊

Graduate Student of Geo-environmental Science, Rissho University＊＊
Faculty of Geo-environmental Science, Rissho University

keywords: facial skin surface, skin surface moisture, statistical analysis

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