Journal of Nuclear and Radiochemical Sciences, Vol. 24, pp. 1-12, 2024

ArticlesBeryllium-7 depositions in Hokuriku, Japan in winter (1991–2021): Factors causing the
temporal variation
Keisuke Yoshidaa,b*, Shingo Katoc, Shinichi Okuyamab, Yuu Ishimorib, Mutsuo Inoueaa

Low Level Radioactivity Laboratory, Institute of Nature and Environmental Technology, Kanazawa University,
Wake O-24, Nomi, Ishikawa 923-1224, Japanb
Safety and Quality Assurance Management Office, Head Office of Tsuruga Decommissioning Demonstration,
Sector of Tsuruga Decommissioning Demonstration, Japan Atomic Energy Agency, Shiraki 2-1, Tsuruga, Fukui
919-1279, Japanc
Department of Radiation Protection, Nuclear Science Research Institute, Sector of Nuclear Science Research,
Japan Atomic Energy Agency, Shirakata 2-4, Tokai, Ibaraki 319-1195, Japan
Received February 19, 2024; Accepted June 10, 2024; Published online August 1, 2024
The factors causing the temporal variation of 7Be deposition in the Hokuriku region (the Sea of Japan side of central Honshu, the main island of Japan) during winter (November to February) were examined using monthly samples of 7Be deposition conducted over 30 years, spanning from 1991 to 2021. The predominant factors on 7Be
deposition at a Hokuriku region site were as follows: 1) the amount of 7Be generated by cosmic rays, 2) the volume of air transported from the Arctic, and 3) the amount of precipitation at the observation site. The contribution of each of these factors f luctuated depending on the sampling period. The temporal variations in 7 Be
deposition during the first half of the sampling period (1991–2005) were primarily driven by cosmic rays. In contrast, during the latter half of the period (2006–2021), meteorological factors, particularly snowfall, emerged as
significant contributors. This shift in influence was attributed to the effects of climate change in the Hokuriku
region.
Keywords: 7Be deposition, the Hokuriku region, climate change, solar activity

1. Introduction
Beryllium-7 is a cosmogenic radionuclide with a half-life of
53.3 days that is primarily formed through the nuclear spallation reaction between O2 and N2 molecules and cosmic rays
within the atmosphere, mainly in the stratosphere at high latitudes1-3. Following this, 7Be rapidly adheres to atmosphericaerosol particles and is subsequently deposited onto theground through precipitation after the transport along withthese particles 4-6. This unique behavior makes 7Be a widely
recognized tracer, commonly employed in studies of air mass
and aerosol movement dynamics7,8.
During winter, seasonal winds from the Eurasian Continent
prevail over the Japanese archipelago. The air masses transported by these seasonal winds originate from high altitudes inhigh latitude regions9, where large amounts of 7 Be are produced by the spallation with cosmic rays. As these winds traverse over the warm surface of the Sea of Japan, they absorb
large amounts of moisture. The collision of the air mass withthe mountainous terrain of the Japanese Archipelago results in
powerful updrafts, forming dense clouds and, subsequently,
heavy rain or snowfall. Consequently, the Hokuriku region,
located on the Sea of Japan side of central Honshu, stands out
as one of Japan’s foremost areas for 7Be deposition, alongsideother coastal regions along the Sea of Japan9-13.
Notably, the winter monsoon is accompanied by high 7Be
deposition every year, but the actual quantity of 7Be deposition
varies annually11. This fluctuation may be attributed to two
primary factors: firstly, alterations in the volume of air masses
originating from the Arctic region, and secondly, the 11-year
cycle of solar activity as the atmospheric 7Be concentrations*Corresponding author. E-mail: yoshida.keisuke@jaea.go.jp

are indicative of solar activity levels14.
In this study, we examined 7Be deposition in the Hokuriku
region for 30 years period (1991–2021) focusing on winter season (November–February), and discussed the factor causing
the amount of 7Be deposition, comparing with solar activity
and meteorological phenomena.
2. Materials and methods
2.1. Study area. The study area and sampling site are illustrated in Fig. 1. The sampling site, referred to as site FK, issituated in Fukui City, located to the north on a plain facingt he Se a of Japa n ( long it ude, 36° 0 4’27 ” N; lat it u de,
136°15’39”E; height above sea level:12 m). The sampling site
is located near the center of the Fukui Plain (approximately 40
km north to south and approximately 10 to 15 km wide fromeast to west). The north side faces to the Sea of Japan, and the
opposite side is characterized by the presence of mountainous
backbone about 1000 meters in height, gradually decreasingfrom east to west to a few hundred meters.
During winter, site FK is greatly affected by the monsoon,
making it distinctively representative of the Hokuriku region15.
Consequently, site FK is an ideal location for observing 7Be
deposition and associated meteorological phenomena during
the winter season.
2.2. Experiment2.2.1 Deposition samples. Precipitation and snowfall samples were collected using a metal basin (0.5 m 2) approximately
every month from April 1991 to March 2021. To capture 7Be
deposition, the precipitation and aerosol samples, which con-© 2024 The Japan Society of Nuclear and Radiochemical Sciences
Published on Web 08/01/2024

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YoshidaJ. Nucl. Radiochem. Sci., Vol. 24, 2024
45

Latitude(degree)

Eurasian Continent
Sea of Japan

40

Hokuriku region

37

35

30

36
125

130

135

140

145

Longitude(degree)

135

136

Longitude(°E)

137

Figure 1. Location of a sampling site (FK) with a weather observation site in Fukui City, Hokuriku region, Japan.

tained both water and adhered aerosols, underwent batch processing involving a combination of anion (Powdex® PAO;
GTS-PX-1000) and cation exchange resin (Powdex® PCH;
GTS-PX-2000) from Graver Technologies, located in Glasgow,
Delaware, USA. Additionally, the supernatant was filteredusing a resin column (PAO and PCH resin) by column operation. Following this, the resin was dried at 45℃ for two days
and then homogenized and packed into a cylindrical plastic
container measuring 10 cm in diameter and 9.5 cm in depth for
γ-spectrometry.
Germanium semiconductor detectors were employed formeasuring the γ-ray of 7Be (at 477 keV) within the resin samples. To calibrate the 7Be activity of the samples, a mock-up
sample was prepared using a standard source (Eckert &Ziegler Nuclitec, Braunschweig, Germany) containing 57Co,
60
Co, 85Sr, 88Y, 109Cd, 113Sn, 137Cs, 139Ce, 203Hg, and 241Am, ranging from 60–1836 keV. The 7 Be counting efficiency wasdetermined by interpolation of the counting efficiencies
obtained for the γ-rays. The counting time was 70000 seconds. The analytical precision for 7Be, based on one σ of thecounting statistics, ranged from 0.1% to 4%.
To compare the data across various sampling collection
periods (which spanned from 20 to 41 days), the 7Be deposit io n s u nd e r we nt c or r e c t io n t o va lu e s p e r 30 d ay s.
Furthermore, considering its physical half-life, the 7Be activity
was decay-corrected to the midpoint of the respective sampling period.
2.2.2 Meteorological data. The meteorological data, including precipitation and snowfall, were obtained from the weather
station in the Fukui Plain16 (longitude, 36°03’21”N; latitude,
136°13’22”E; height above sea level:12 m), locating in a distance of approximately 4 km from the sampling site. The
snowfall in this study is the snow depth from the Japan
Meteorological Agency17, which does not directly correspondto the precipitation by the variation of snow density. However,
we consider that the snow depth is a useful index to discuss
7
Be deposition.
Given the varying number of sampling days across different
periods, we adjusted the precipitation and snowfall data toreflect values per 30 days.
Subsequently, the 7 Be concentration was calculated by
dividing the 7Be deposition by the corresponding amount ofprecipitation, neglecting the small effect of dry deposition (atapproximately 10–20% of the total at mid-latitudes)5,6.
3. Results and discussion
3.1. Temporal variation in 7Be deposition in winter. The
γ-spectrometry results are listed in Table S1. The temporalvariations in precipitation, snowfall, sunspot numbers18, and7
Be deposition and concentration during the winter months(November to February) are illustrated in Fig. 2. In winter,
precipitation and snowfall exhibited a wide range, with values
spanning from 570 to 1300 mm and 8 to 400 mm, respectively(Fig. 2a). Sunspot numbers in winter displayed significant
variability, ranging from 8 to 800, with peak levels observedin 1991, 2001, and 2013, and the lowest recorded in 1995, 2008,
and 2019 (Fig. 2b). Beryllium-7 deposition and concentration
during winter ranged from 1760 to 4080 Bq/m 2 and 2.0 to 3.9
Bq/L, respectively (Fig. 2c and 2d).
The quantities of 7Be in aerosols in the atmosphere exhibited periodic changes, reflecting an 11-year cycle in galactic
cosmic ray intensity14, with lower 7Be deposition during periods of higher sunspot numbers13. Throughout the study
period, the years with the highest sunspot numbers were 1991,
1999–2002, and 2011–2014, coinciding with lower 7Be concentrations, which is the same trend observed previously11.
Therefore, solar activity is considered to be important factor toaffect the temporal variation of 7Be deposition.
In the winters of 2006, 2018, and 2019, widely spread areas
within the Hokuriku region experienced notably lower snowfall compared to other years19-21 (Fig. 2a). Correspondingly,
during these years, low 7Be deposition levels were observed atsite FK (Fig. 2c). In contrast, 2017 stood out with a high 7Be
deposition of 4080 Bq/m2, accompanied by substantial precipitation and snowfall, which exceeded the levels seen in 2018
(2284 Bq/m 2). This suggests that the quantity of 7Be deposition is considered to be inf luenced by the transport of air
masses from the Arctic region, which brings heavy precipitation and snowfall to the Hokuriku region. Furthermore, during the winters of 1991 and 2005, low 7 Be concentrations,which were concurrent with low 7Be deposition levels, wereobserved. Therefore, it can be inferred that temporal variations in the 7Be concentration are correlated with meteorological factors such as precipitation and snowfall, which also

J. Nucl. Radiochem. Sci., Vol. 24, 2024

Beryllium-7 depositions in Hokuriku, Japan in winter (1991–2021):a3

Sunspot number

Precipitation (mm)Snowfall (mm)

b

Year

d

Year

7Be deposition (Bq/m2)

7Be concentration (Bq/L)

c

Year

Year

Figure 2. Temporal variations of the arithmetic sums of monthly data from November to February in a) precipitation (total of rainfall and snowfall) and snowfall, b) sunspot number, c) 7Be deposition, and d) 7Be concentration in winter season (November–February) from 1991 to 2021. The
7
Be concentration was calculated by dividing total sum of 7Be deposition from November to February by the total sum of precipitation during thesame period.

a
7Be deposition (Bq/m2)

7Be deposition (Bq/m2)b

Snowfall (mm)Precipitation (mm)7Be deposition (Bq/m2)

d

7Be deposition (Bq/m2)cSunspot number

7Be concentration (Bq/L)

Figure 3. Beryllium-7 deposition vs. a) precipitation, b) snowfall, c) sunspot number, and d) 7Be concentration in winter from 1991 to 2021. The
calculation method for each value is the same as in Fig. 2.

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YoshidaJ. Nucl. Radiochem. Sci., Vol. 24, 2024

affect Be deposition.
Figure 3 presents the 7Be depositions at site FK during winter against precipitations, snowfalls, sunspot numbers, and 7Be
concentrations. Notably, the 7Be deposition positively correlates with meteorological factors, specifically precipitation andsnowfall (Fig. 3a and 3b). While the 7Be deposition also demonstrates correlations with the sunspot number, indicative of
solar activity, and the 7Be concentration, these relationships
are weaker in comparison to the meteorological factors (precipitation and snowfall). It is worth mentioning that Solar
activity does influence the 7Be concentration within aerosols14(Fig. 3c). Figure 4 presents the correlation between the 7Be
concentrations and sunspot numbers (n = 30, R 2 = 0.33) indicating a relatively stronger relationship than that observed
between 7 Be deposition and sunspot number (n = 30, R 2 =0.13). Consequently, sunspot number are considered to have amore direct impact on the 7Be concentration in precipitation.
3.2. Factors affecting 7 Be deposition in winter. In the
Hokuriku region during winter, 7 Be deposition is primarily
governed by three key factors: 1) the amount of 7Be producedby cosmic rays, 2) the amount of air transport from the Arctic,
and 3) the amount of precipitation at the observation site.
Quantifying the contribution of each factor is difficult because
these factors complicatedly affect to 7Be deposition with different degrees. Especially, the amount of air transport fromthe Arctic and precipitation are affected by various weather
phenomena.
Notably, the temporal variation in sunspot numbers held
significance prior to 2005 (Fig. 2b), whereas the variability inprecipitation and snowfall after 2006 exceeded that observed
before 2005 (Fig. 2a). To examine these variations, the30-year period was tentatively divided into two halves: thefirst half spanning from 1991 to 2005 and the latter half from

7Be concentration (Bq/L)

7

Sunspot number

Figure 4. Beryllium-7 concentration vs. sunspot number. The calculation method for each value is the same as in Fig. 2.

2006 to 2021. The correlations between 7Be deposition andprecipitation, snowfall, sunspot number, and the 7Be concentration within each period are compared in Fig. 5.
The correlation between 7Be deposition and precipitation
was notably stronger in the latter half of the observation period(n = 15, R 2 = 0.67) when compared with the first half (n = 15,
R 2 = 0.010) (Fig. 5a). Particularly, 7 Be deposition showed asignificant correlation with snowfall in the latter half (n = 15,
R 2 = 0.83) contrasting with the first half (n = 15, R 2 = 0.022)(Fig. 5b). It is worth highlighting that the variation in meteorological factors was more extensive in the latter half than ina
7Be deposition (Bq/m2)

7Be deposition (Bq/m2)bPrecipitation (mm)dSnowfall (mm)7Be deposition (Bq/m2)

7Be deposition (Bq/m2)cSunspot number

7Be concentration (Bq/L)

Figure 5. Beryllium-7 deposition vs. a) precipitation, b) snowfall, c) sunspot number, and d) 7Be concentration. Dotted and solid lines indicate
the period during the first (1991 to 2005) and latter (2006 to 2020) halves in this study, respectively. The calculation method for each value is thesame as in Fig. 2.

J. Nucl. Radiochem. Sci., Vol. 24, 2024

Beryllium-7 depositions in Hokuriku, Japan in winter (1991–2021):

the first half (Fig. 2a). This observation suggests that meteorological factors had a more substantial impact on the temporalvariation in 7Be deposition during the latter half of the study
period. Furthermore, during the latter half, the correlation
with snowfall was more pronounced than precipitation. In the
Hokuriku region, the southeastward monsoon frequently
brings heavy snowfall and cold air from high latitudes. Snowturns into rain when the temperature rises above 0°C, and cold
air is essential for snowfall. In contrast, rain can occur during
the passage of a low-pressure system, independent of thesoutheastward monsoon and cold air. Therefore, an increaseof snowfall may show a better correlation with 7Be than that of
precipitation because the increase of snowfall means thearrival of cold air from high latitudes.
In the first half, 7Be deposition displayed a strong correlation with the 7Be concentration (n = 15, R 2 = 0.64) (Fig. 5d).
However, this correlation was unclear in the latter half of thestudy period (n = 15, R 2 = 0.014). Similarly, the correlation
between 7Be deposition and sunspot number in the first half(n = 15, R 2 = 0.21) is stronger than that of in the latter half(n = 15, R 2 = 0.031) (Fig. 5c). Whereas the amounts of precipitation and snowfall in the first half have been less variable
than those in later half (Fig. 2a), the number of sunspots in thefirst half was approximately double that of the latter half
(Fig. 2b). The solar activity affects to the 7Be concentration as
discussed section 3.1. Therefore, the 7Be concentration is considered to exert a more significant influence on the temporalvariation in the 7Be deposition during the first half.
3.3. 7Be deposition in winter and climate change. Snowfallin the Hokuriku region has declined since 1962, reflecting theeffects of climate change22. Paradoxically, climate change may
increase the water vapor supply from the Sea of Japan, and theJapan Sea polar air mass convergence zone (JPCZ), a mesoscale meteorological phenomenon which locally causes heavy
snowfall in the Hokuriku region, is considered to become
active23. If climate change continues, it is anticipated that thetemporal variations in winter precipitation and snowfall in the
Hokuriku region will intensify. This suggests that the influence of meteorological factors, specifically precipitation andsnowfall, could surpass that of solar activity. To gain a deeper
understanding of how climate change affects the temporalvariation in 7Be deposition during winter, it is imperative to
conduct continuous observations of 7Be deposition. Currently,
we are actively engaged in a project focused on this subject.
4. Conclusion
From 1991 to 2021, we conducted a 30-year investigation
into the temporal variations of 7Be deposition and concentration in Fukui City, located in the Hokuriku region of Japan,
during the winter months (November to February). The primary objective of our study was to elucidate the factors driving the temporal variations in 7Be deposition. The temporalf luctuations in 7 Be deposition are primarily inf luenced bythree key factors: the rate of 7Be production due to cosmic rayintensity, the amount of precipitation, and the volume of airtransported from the Arctic region. In the initial half of ourobservation period (1991–2005), the temporal variations in 7Be
deposition predominantly mirrored the fluctuations in cosmic
rays.
However, during the latter half of our study period (2006–2021), a more pronounced correlation emerged between 7Be
deposition and meteorological factors, particularly snowfall.
The shift in inf luence may be attributed to the increase ofvariability in precipitation and snowfall in the Hokuriku
region, which is considered to be caused by climate change.

5

Acknowledgments
The 7Be data were obtained from an environmental radioactivity survey conducted around a nuclear power plant (Fukui
Prefectural Environmental Radioactivity Measurement
Technology Conference). We express our deep gratitude to allm e m b e r s of t h e F u k u i P r efe c t u r a l E nv i r o n m e n t a lRadioactivity Measurement Technology Council for providing
the data.
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Appendix
TABLE S1. Monthly 7Be deposition, concentration, precipitation, and snowfall at sampling site.
7

Sampling information
Year

Month

1991

4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8

1992

1993

1994

Period1991/04/05
1991/05/09
1991/06/06
1991/07/05
1991/08/07
1991/09/09
1991/10/05
1991/11/07
1991/12/04
1992/01/09
1992/02/06
1992/03/04
1992/04/08
1992/05/08
1992/06/02
1992/07/07
1992/08/04
1992/09/01
1992/10/06
1992/11/05
1992/12/01
1993/01/06
1993/02/04
1993/03/04
1993/04/06
1993/05/07
1993/06/01
1993/07/07
1993/08/03
1993/09/02
1993/10/04
1993/11/02
1993/12/01
1994/01/06
1994/02/02
1994/03/01
1994/04/06
1994/05/10
1994/06/07
1994/07/06
1994/08/02-

1991/05/09
1991/06/06
1991/07/05
1991/08/07
1991/09/09
1991/10/05
1991/11/07
1991/12/04
1992/01/09
1992/02/06
1992/03/04
1992/04/08
1992/05/08
1992/06/02
1992/07/07
1992/08/04
1992/09/01
1992/10/06
1992/11/05
1992/12/01
1993/01/06
1993/02/04
1993/03/04
1993/04/06
1993/05/07
1993/06/01
1993/07/07
1993/08/03
1993/09/02
1993/10/04
1993/11/02
1993/12/01
1994/01/06
1994/02/02
1994/03/01
1994/04/06
1994/05/10
1994/06/07
1994/07/06
1994/08/02
1994/09/05

Days

Be deposition
2(Bq/m )

34
28
29
33
33
26
33
27
36
28
27
35
30
25
35
28
28
35
30
26
36
29
28
33
31
25
36
27
30
32
29
29
36
27
27
36
34
28
29
27
34

213 ± 1167 ± 3237 ± 1248 ± 139 ± 198 ± 1266 ± 1457 ± 1286 ± 1535 ± 3486 ± 3
246 ± 1
255 ± 1
189 ± 1102 ± 1114 ± 187 ± 188 ± 1433 ± 1268 ± 1863 ± 3824 ± 2723 ± 3223 ± 1212 ± 1137 ± 1254 ± 1203 ± 1124 ± 1205 ± 1324 ± 1343 ± 1888 ± 2625 ± 3451 ± 1310 ± 1117 ± 1140 ± 1133 ± 118 ± 0.575 ± 1

7

Be concentration(Bq/L)
0.80 ± 0.008
1.65 ± 0.024
0.97 ± 0.005
0.99 ± 0.005
0.56 ± 0.010
0.63 ± 0.008
2.20 ± 0.008
2.24 ± 0.007
1.70 ± 0.006
1.87 ± 0.010
2.65 ± 0.015
1.13 ± 0.005
1.72 ± 0.007
1.85 ± 0.014
1.11 ± 0.010
0.76 ± 0.007
0.94 ± 0.010
1.35 ± 0.014
2.21 ± 0.006
1.97 ± 0.010
3.20 ± 0.010
2.68 ± 0.009
2.94 ± 0.011
3.07 ± 0.015
1.57 ± 0.008
1.31 ± 0.017
0.86 ± 0.003
0.94 ± 0.006
0.61 ± 0.006
0.73 ± 0.004
2.39 ± 0.010
2.64 ± 0.009
3.59 ± 0.007
2.36 ± 0.012
3.01 ± 0.009
3.16 ± 0.010
1.20 ± 0.012
1.39 ± 0.015
1.15 ± 0.010
0.38 ± 0.010
1.97 ± 0.021

Precipitation Snowfall
(mm)
(mm)
134
115
252
227
69
173
121
226
159
286
190
186
163
118
84
167
93
60
203
152
263
286
246
70
152
101
264
249
219
262
136
143
240
245
156
90
95
90
131
51
37

0
0
0
0
0
0
0
0
12
35
50
0
0
0
0
0
0
0
0
0
13
59
21
0
0
0
0
0
0
0
0
0
13
136
91
1
0
0
0
0
0

J. Nucl. Radiochem. Sci., Vol. 24, 2024

Beryllium-7 depositions in Hokuriku, Japan in winter (1991–2021):
7

Sampling information
Year

1995

1996

1997

1998

1999

Month
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6

Period1994/09/05
1994/10/03
1994/11/09
1994/12/08
1995/01/13
1995/02/07
1995/03/07
1995/04/06
1995/05/10
1995/06/06
1995/07/06
1995/08/09
1995/09/06
1995/10/01
1995/11/07
1995/12/06
1996/01/08
1996/02/05
1996/03/01
1996/04/02
1996/05/07
1996/06/04
1996/07/02
1996/08/07
1996/09/02
1996/10/01
1996/11/07
1996/12/10
1997/01/08
1997/02/03
1997/03/05
1997/04/09
1997/05/07
1997/06/04
1997/07/10
1997/08/08
1997/09/03
1997/10/08
1997/11/05
1997/12/09
1998/01/09
1998/02/04
1998/03/05
1998/04/09
1998/05/07
1998/06/03
1998/07/09
1998/08/05
1998/09/02
1998/10/08
1998/11/05
1998/12/02
1999/01/05
1999/02/04
1999/03/03
1999/04/07
1999/05/07
1999/06/03-

1994/10/03
1994/11/09
1994/12/08
1995/01/13
1995/02/07
1995/03/07
1995/04/06
1995/05/10
1995/06/06
1995/07/06
1995/08/09
1995/09/06
1995/10/01
1995/11/07
1995/12/06
1996/01/08
1996/02/05
1996/03/01
1996/04/02
1996/05/07
1996/06/04
1996/07/02
1996/08/07
1996/09/02
1996/10/01
1996/11/07
1996/12/10
1997/01/08
1997/02/03
1997/03/05
1997/04/09
1997/05/07
1997/06/04
1997/07/10
1997/08/08
1997/09/03
1997/10/08
1997/11/05
1997/12/09
1998/01/09
1998/02/04
1998/03/05
1998/04/09
1998/05/07
1998/06/03
1998/07/09
1998/08/05
1998/09/02
1998/10/08
1998/11/05
1998/12/02
1999/01/05
1999/02/04
1999/03/03
1999/04/08
1999/05/07
1999/06/03
1999/07/08

Days

Be deposition
2(Bq/m )

28
37
29
36
25
28
30
34
27
30
34
28
25
37
29
33
28
25
32
35
28
28
36
26
29
37
33
29
26
30
35
28
28
36
29
26
35
28
34
31
26
29
35
28
27
36
27
28
36
28
27
34
30
27
36
30
27
35

349 ± 2254 ± 1555 ± 31119 ± 4730 ± 4375 ± 2322 ± 2286 ± 2413 ± 2307 ± 2355 ± 2163 ± 293 ± 1412 ± 21055 ± 4809 ± 4843 ± 3227 ± 2370 ± 2169 ± 1279 ± 2126 ± 125 ± 177 ± 1283 ± 0.2
264 ± 11000 ± 3
586 ± 3810 ± 4510 ± 2392 ± 2140 ± 1251 ± 2267 ± 1287 ± 244 ± 1322 ± 2309 ± 2570 ± 2458 ± 3894 ± 3281 ± 1363 ± 290 ± 1177 ± 2166 ± 199 ± 1215 ± 2326 ± 2108 ± 1789 ± 4611 ± 31102 ± 5462 ± 2361 ± 2193 ± 293 ± 1270 ± 2

7

Be concentration(Bq/L)
1.88 ± 0.013
2.03 ± 0.012
4.04 ± 0.018
2.91 ± 0.008
2.59 ± 0.015
2.63 ± 0.016
2.50 ± 0.017
1.84 ± 0.012
1.82 ± 0.012
1.15 ± 0.008
0.92 ± 0.006
1.42 ± 0.014
2.94 ± 0.044
2.97 ± 0.014
3.50 ± 0.014
4.36 ± 0.016
3.08 ± 0.014
2.61 ± 0.025
2.06 ± 0.010
2.06 ± 0.015
3.32 ± 0.020
0.62 ± 0.006
0.53 ± 0.010
0.32 ± 0.005
1.39 ± 0.001
1.78 ± 0.008
2.65 ± 0.009
3.35 ± 0.016
4.11 ± 0.019
3.24 ± 0.016
1.72 ± 0.008
3.04 ± 0.027
1.10 ± 0.008
0.93 ± 0.006
1.11 ± 0.006
4.33 ± 0.094
2.28 ± 0.011
2.63 ± 0.015
1.77 ± 0.007
2.82 ± 0.013
3.35 ± 0.013
2.26 ± 0.013
2.08 ± 0.009
0.66 ± 0.006
0.72 ± 0.007
0.87 ± 0.005
0.39 ± 0.005
0.76 ± 0.006
0.85 ± 0.004
0.74 ± 0.005
3.88 ± 0.018
4.59 ± 0.019
2.82 ± 0.013
2.41 ± 0.014
2.30 ± 0.011
2.03 ± 0.014
0.89 ± 0.011
1.01 ± 0.006

Precipitation Snowfall
(mm)
(mm)
199
98
147
373
316
143
133
151
227
276
329
132
38
124
291
202
264
97
169
66
99
218
43
273
196
140
320
211
212
147
183
56
235
207
303
11
121
143
255
183
287
120
149
171
236
160
307
292
331
162
218
133
365
198
135
111
100
228

0
0
0
43
143
20
0
0
0
0
0
0
0
0
0
18
117
66
4
2
0
0
0
0
0
0
35
2
53
20
0
0
0
0
0
0
0
0
2
8
81
17
0
0
0
0
0
0
0
0
0
1
113
48
0
0
0
0

7

8

YoshidaJ. Nucl. Radiochem. Sci., Vol. 24, 2024
7

Sampling information
Year

2000

2001

2002

2003

2004

Month
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4

Period1999/07/08
1999/08/04
1999/09/07
1999/10/07
1999/11/08
1999/12/10
2000/01/07
2000/02/02
2000/03/09
2000/04/06
2000/05/10
2000/06/05
2000/07/06
2000/08/03
2000/09/06
2000/10/05
2000/11/07
2000/12/05
2001/01/06
2001/02/05
2001/03/06
2001/04/02
2001/05/07
2001/06/05
2001/07/02
2001/08/02
2001/09/04
2001/10/02
2001/11/05
2001/12/04
2002/01/07
2002/02/04
2002/03/05
2002/04/04
2002/05/08
2002/06/04
2002/07/04
2002/08/06
2002/09/04
2002/10/03
2002/11/13
2002/12/03
2003/01/08
2003/02/04
2003/03/04
2003/04/01
2003/05/07
2003/06/04
2003/07/01
2003/08/05
2003/09/03
2003/10/08
2003/11/04
2003/12/02
2004/01/06
2004/02/03
2004/03/02
2004/04/05-

1999/08/04
1999/09/07
1999/10/07
1999/11/08
1999/12/10
2000/01/07
2000/02/02
2000/03/09
2000/04/06
2000/05/10
2000/06/05
2000/07/06
2000/08/03
2000/09/06
2000/10/05
2000/11/07
2000/12/05
2001/01/06
2001/02/05
2001/03/06
2001/04/02
2001/05/07
2001/06/05
2001/07/02
2001/08/02
2001/09/04
2001/10/02
2001/11/05
2001/12/04
2002/01/07
2002/02/04
2002/03/05
2002/04/04
2002/05/08
2002/06/04
2002/07/04
2002/08/06
2002/09/04
2002/10/03
2002/11/13
2002/12/03
2003/01/08
2003/02/04
2003/03/04
2003/04/01
2003/05/07
2003/06/04
2003/07/01
2003/08/05
2003/09/03
2003/10/07
2003/11/04
2003/12/02
2004/01/06
2004/02/03
2004/03/02
2004/04/05
2004/05/07

Days

Be deposition
2(Bq/m )

27
34
30
32
32
28
26
36
28
34
26
31
28
34
29
33
28
32
30
29
27
35
29
27
31
33
28
34
29
34
28
29
30
34
27
30
33
29
29
41
20
36
27
28
28
36
28
27
35
29
34
27
28
35
28
28
34
32

65 ± 156 ± 1
182 ± 1136 ± 1885 ± 3745 ± 3402 ± 2770 ± 3307 ± 2330 ± 2127 ± 1101 ± 155 ± 1
11 ± 0.4
190 ± 2259 ± 1
182 ± 1864 ± 4874 ± 3398 ± 2292 ± 2133 ± 1
118 ± 1
189 ± 282 ± 1123 ± 1249 ± 2128 ± 1480 ± 3999 ± 4679 ± 3278 ± 2164 ± 1325 ± 293 ± 1
153 ± 1125 ± 139 ± 1150 ± 11225 ± 3
365 ± 3859 ± 3533 ± 3249 ± 2270 ± 2276 ± 176 ± 1187 ± 2237 ± 2136 ± 196 ± 1
158 ± 1285 ± 2725 ± 3944 ± 4613 ± 3225 ± 1
213 ± 1

7

Be concentration(Bq/L)
0.78 ± 0.010
0.30 ± 0.003
1.21 ± 0.009
1.16 ± 0.009
3.21 ± 0.011
2.33 ± 0.009
3.35 ± 0.022
2.73 ± 0.010
1.77 ± 0.011
2.35 ± 0.013
2.15 ± 0.022
0.76 ± 0.007
0.75 ± 0.011
0.15 ± 0.005
0.54 ± 0.004
1.29 ± 0.007
1.88 ± 0.015
3.29 ± 0.013
2.10 ± 0.009
2.50 ± 0.014
2.83 ± 0.015
1.56 ± 0.011
1.85 ± 0.019
0.66 ± 0.006
1.09 ± 0.012
0.99 ± 0.009
0.76 ± 0.006
0.86 ± 0.007
3.38 ± 0.017
3.22 ± 0.012
1.94 ± 0.010
2.28 ± 0.017
0.99 ± 0.008
1.51 ± 0.007
1.50 ± 0.019
1.43 ± 0.014
0.63 ± 0.005
1.25 ± 0.024
0.87 ± 0.007
2.99 ± 0.008
2.26 ± 0.015
2.87 ± 0.009
2.76 ± 0.015
1.41 ± 0.009
2.55 ± 0.017
1.25 ± 0.006
1.20 ± 0.015
0.96 ± 0.010
0.91 ± 0.006
0.78 ± 0.007
1.37 ± 0.012
2.18 ± 0.017
1.45 ± 0.010
2.99 ± 0.011
3.82 ± 0.018
2.33 ± 0.010
1.91 ± 0.010
1.44 ± 0.008

Precipitation Snowfall
(mm)
(mm)
99
168
151
113
258
389
129
227
204
116
70
137
77
65
377
182
104
279
389
154
122
70
68
329
73
124
326
136
157
293
350
118
171
190
76
100
188
34
172
310
259
291
193
176
109
184
72
209
232
188
62
92
190
249
247
263
108
157

0
0
0
0
0
70
29
98
28
0
0
0
0
0
0
0
0
24
188
33
33
0
0
0
0
0
0
0
0
27
47
43
0
0
0
0
0
0
0
0
0
62
62
3
16
0
0
0
0
0
0
0
0
13
94
76
35
0

J. Nucl. Radiochem. Sci., Vol. 24, 2024

Beryllium-7 depositions in Hokuriku, Japan in winter (1991–2021):
7

Sampling information
Year

2005

2006

2007

2008

2009

Month
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2

Period2004/05/07
2004/06/02
2004/07/06
2004/08/02
2004/09/03
2004/10/05
2004/11/02
2004/12/01
2005/01/05
2005/02/02
2005/03/01
2005/04/01
2005/05/02
2005/06/01
2005/07/01
2005/08/01
2005/09/01
2005/10/03
2005/11/01
2005/12/01
2005/12/28
2006/02/01
2006/03/02
2006/04/04
2006/05/01
2006/06/01
2006/07/03
2006/08/01
2006/09/01
2006/10/02
2006/11/01
2006/12/01
2007/01/04
2007/02/01
2007/03/02
2007/04/02
2007/05/07
2007/06/05
2007/07/02
2007/08/07
2007/09/04
2007/10/01
2007/11/07
2007/12/03
2008/01/07
2008/02/04
2008/03/03
2008/04/04
2008/05/07
2008/06/02
2008/07/01
2008/08/05
2008/09/02
2008/10/03
2008/11/04
2008/12/01
2009/01/05
2009/02/02-

2004/06/02
2004/07/06
2004/08/02
2004/09/03
2004/10/05
2004/11/02
2004/12/01
2005/01/05
2005/02/02
2005/03/01
2005/04/01
2005/05/02
2005/06/01
2005/07/01
2005/08/01
2005/09/01
2005/10/03
2005/11/01
2005/12/01
2005/12/28
2006/02/01
2006/03/02
2006/04/04
2006/05/01
2006/06/01
2006/07/03
2006/08/01
2006/09/01
2006/10/02
2006/11/01
2006/12/01
2007/01/04
2007/02/01
2007/03/02
2007/04/02
2007/05/07
2007/06/05
2007/07/02
2007/08/07
2007/09/04
2007/10/01
2007/11/07
2007/12/03
2008/01/07
2008/02/04
2008/03/03
2008/04/04
2008/05/07
2008/06/02
2008/07/01
2008/08/05
2008/09/02
2008/10/03
2008/11/04
2008/12/01
2009/01/05
2009/02/02
2009/03/02

Days

Be deposition
2(Bq/m )

26
34
27
32
32
28
29
35
28
27
31
31
30
30
31
31
32
29
30
27
35
29
33
27
31
32
29
31
31
30
30
34
28
29
31
35
29
27
36
28
27
37
26
35
28
28
32
33
26
29
35
28
31
32
27
35
28
28

252 ± 1117 ± 193 ± 182 ± 1
241 ± 1179 ± 1315 ± 2492 ± 21129 ± 4483 ± 2243 ± 1229 ± 1152 ± 1157 ± 1128 ± 1
141 ± 175 ± 1
213 ± 1601 ± 31051 ± 5
631 ± 2112 ± 1493 ± 2228 ± 1282 ± 1121 ± 1228 ± 259 ± 1172 ± 1117 ± 1410 ± 2523 ± 3591 ± 2297 ± 3624 ± 2327 ± 1225 ± 1151 ± 1152 ± 187 ± 1
107 ± 1218 ± 1
501 ± 31206 ± 3
421 ± 2609 ± 3467 ± 2213 ± 1
131 ± 1
209 ± 1151 ± 1136 ± 1166 ± 1247 ± 1578 ± 2669 ± 2815 ± 3401 ± 2

7

Be concentration(Bq/L)
0.70 ± 0.004
0.68 ± 0.005
0.39 ± 0.004
0.94 ± 0.010
0.71 ± 0.004
0.72 ± 0.005
2.12 ± 0.011
2.22 ± 0.009
2.77 ± 0.011
2.60 ± 0.011
1.31 ± 0.008
3.27 ± 0.017
1.85 ± 0.013
1.44 ± 0.009
0.38 ± 0.003
0.74 ± 0.005
0.62 ± 0.006
1.66 ± 0.011
3.00 ± 0.013
1.78 ± 0.007
3.22 ± 0.012
0.60 ± 0.005
2.44 ± 0.008
1.99 ± 0.013
1.71 ± 0.008
2.25 ± 0.015
0.37 ± 0.003
1.30 ± 0.015
0.68 ± 0.005
1.87 ± 0.014
2.72 ± 0.012
2.71 ± 0.011
4.11 ± 0.018
2.06 ± 0.023
3.55 ± 0.013
3.10 ± 0.014
2.29 ± 0.013
0.65 ± 0.005
0.78 ± 0.005
0.65 ± 0.006
1.18 ± 0.011
1.54 ± 0.009
3.01 ± 0.014
2.99 ± 0.008
4.11 ± 0.020
3.15 ± 0.013
2.99 ± 0.012
1.70 ± 0.009
0.89 ± 0.008
1.50 ± 0.009
0.95 ± 0.006
1.17 ± 0.009
1.13 ± 0.007
2.10 ± 0.010
2.28 ± 0.011
2.85 ± 0.009
2.96 ± 0.011
3.09 ± 0.016

Precipitation Snowfall
(mm)
(mm)
359
153
283
82
319
276
154
215
407
193
186
70
82
109
337
191
120
129
201
745
157
181
202
118
165
54
633
44
253
63
151
193
144
139
181
87
105
268
162
159
94
119
205
369
102
214
142
114
182
140
141
129
142
125
253
234
275
130

0
0
0
0
0
0
0
10
118
101
42
0
0
0
0
0
0
0
0
156
87
37
42
0
0
0
0
0
0
0
0
11
3
9
26
0
0
0
0
0
0
0
0
21
40
96
6
0
0
0
0
0
0
0
4
34
90
12

9

10

YoshidaJ. Nucl. Radiochem. Sci., Vol. 24, 2024
7

Sampling information
Year

2010

2011

2012

2013

Month
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12

Period2009/03/02
2009/04/06
2009/05/08
2009/06/02
2009/07/06
2009/08/03
2009/09/02
2009/10/01
2009/11/02
2009/12/01
2010/01/04
2010/02/01
2010/03/02
2010/04/05
2010/05/07
2010/06/02
2010/07/05
2010/08/02
2010/09/07
2010/10/05
2010/11/02
2010/12/01
2011/01/05
2011/02/08
2011/03/01
2011/04/04
2011/05/09
2011/06/01
2011/07/04
2011/08/01
2011/09/06
2011/10/03
2011/11/08
2011/12/05
2012/01/10
2012/02/06
2012/03/06
2012/04/02
2012/05/07
2012/06/05
2012/07/03
2012/08/06
2012/09/04
2012/10/02
2012/11/05
2012/12/03
2013/01/04
2013/02/04
2013/03/04
2013/04/03
2013/05/01
2013/06/03
2013/07/01
2013/08/01
2013/09/02
2013/10/01
2013/11/01
2013/12/02-

2009/04/06
2009/05/08
2009/06/02
2009/07/06
2009/08/03
2009/09/02
2009/10/01
2009/11/02
2009/12/01
2010/01/04
2010/02/01
2010/03/02
2010/04/05
2010/05/07
2010/06/02
2010/07/05
2010/08/02
2010/09/07
2010/10/05
2010/11/02
2010/12/01
2011/01/05
2011/02/08
2011/03/01
2011/04/04
2011/05/09
2011/06/01
2011/07/04
2011/08/01
2011/09/06
2011/10/03
2011/11/08
2011/12/05
2012/01/10
2012/02/06
2012/03/06
2012/04/02
2012/05/07
2012/06/05
2012/07/03
2012/08/06
2012/09/04
2012/10/02
2012/11/05
2012/12/03
2013/01/04
2013/02/04
2013/03/04
2013/04/03
2013/05/01
2013/06/03
2013/07/01
2013/08/01
2013/09/02
2013/10/01
2013/11/01
2013/12/02
2014/01/05

Days

Be deposition
2(Bq/m )

35
32
25
34
28
30
29
32
29
34
28
29
34
32
26
33
28
36
28
28
29
35
34
21
34
35
23
33
28
36
27
36
27
36
27
29
27
35
29
28
34
29
28
34
28
32
31
28
30
28
33
28
31
32
29
31
31
34

550 ± 2297 ± 2212 ± 1173 ± 1302 ± 2108 ± 1
183 ± 1
208 ± 1348 ± 21369 ± 4853 ± 3590 ± 2416 ± 2265 ± 1170 ± 1
171 ± 182 ± 173 ± 1262 ± 1247 ± 1622 ± 21245 ± 41613 ± 4
185 ± 1
485 ± 3350 ± 2203 ± 2156 ± 1161 ± 1172 ± 1130 ± 1
198 ± 1487 ± 3955 ± 3745 ± 3371 ± 2318 ± 2236 ± 1
162 ± 199 ± 1133 ± 190 ± 1298 ± 1287 ± 1543 ± 3879 ± 4945 ± 3491 ± 2141 ± 1363 ± 294 ± 1
131 ± 1390 ± 2123 ± 1144 ± 1205 ± 1754 ± 3796 ± 37

Be concentration(Bq/L)
2.56 ± 0.009
3.18 ± 0.016
2.40 ± 0.016
1.07 ± 0.006
1.24 ± 0.006
0.92 ± 0.008
2.54 ± 0.016
1.45 ± 0.008
2.39 ± 0.011
4.03 ± 0.010
3.03 ± 0.011
2.41 ± 0.010
1.83 ± 0.008
1.83 ± 0.009
0.95 ± 0.007
0.76 ± 0.004
0.71 ± 0.007
0.78 ± 0.006
0.72 ± 0.004
1.21 ± 0.007
4.35 ± 0.016
2.91 ± 0.007
3.64 ± 0.009
1.72 ± 0.015
3.42 ± 0.018
2.04 ± 0.009
0.61 ± 0.005
1.79 ± 0.011
0.90 ± 0.007
0.61 ± 0.004
0.51 ± 0.004
1.30 ± 0.007
2.59 ± 0.013
2.87 ± 0.008
2.79 ± 0.012
1.90 ± 0.009
2.01 ± 0.011
2.16 ± 0.010
2.17 ± 0.014
0.57 ± 0.005
0.59 ± 0.004
0.91 ± 0.007
0.87 ± 0.004
1.60 ± 0.007
2.05 ± 0.010
2.86 ± 0.010
3.64 ± 0.012
2.73 ± 0.012
2.32 ± 0.018
2.32 ± 0.013
1.34 ± 0.009
0.83 ± 0.007
0.99 ± 0.005
0.54 ± 0.003
0.39 ± 0.003
1.00 ± 0.006
2.33 ± 0.008
2.89 ± 0.010

Precipitation Snowfall
(mm)
(mm)
184
105
88
142
287
114
74
144
146
340
282
237
207
163
172
205
131
78
391
226
148
429
365
139
129
152
435
79
199
244
301
123
209
323
267
196
187
91
80
191
199
112
342
164
302
336
210
180
63
168
70
158
396
234
354
205
324
284

3
0
0
0
0
0
0
0
0
62
93
53
8
0
0
0
0
0
0
0
0
81
216
21
37
0
0
0
0
0
0
0
0
33
141
72
1
0
0
0
0
0
0
0
0
74
58
74
0
0
0
0
0
0
0
0
0
18

J. Nucl. Radiochem. Sci., Vol. 24, 2024

Beryllium-7 depositions in Hokuriku, Japan in winter (1991–2021):
7

Sampling information
Year

Month

2014

1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10

2015

2016

2017

2018

Period2014/01/05
2014/02/03
2014/03/03
2014/04/01
2014/05/01
2014/06/02
2014/07/01
2014/08/01
2014/09/01
2014/10/01
2014/11/04
2014/12/01
2015/01/05
2015/02/02
2015/03/02
2015/04/01
2015/05/01
2015/06/01
2015/07/01
2015/08/03
2015/09/01
2015/10/01
2015/11/02
2015/12/01
2016/01/04
2016/02/01
2016/03/01
2016/04/01
2016/05/02
2016/06/01
2016/07/01
2016/08/01
2016/09/01
2016/10/03
2016/11/01
2016/12/01
2017/01/04
2017/02/01
2017/03/01
2017/04/03
2017/05/01
2017/06/01
2017/07/03
2017/08/01
2017/09/01
2017/10/02
2017/11/01
2017/12/01
2018/01/04
2018/02/01
2018/03/01
2018/04/02
2018/05/01
2018/06/01
2018/07/02
2018/08/01
2018/09/03
2018/10/01-

2014/02/03
2014/03/03
2014/04/01
2014/05/01
2014/06/02
2014/07/01
2014/08/01
2014/09/01
2014/10/01
2014/11/04
2014/12/01
2015/01/05
2015/02/02
2015/03/02
2015/04/01
2015/05/01
2015/06/01
2015/07/01
2015/08/03
2015/09/01
2015/10/01
2015/11/02
2015/12/01
2016/01/04
2016/02/01
2016/03/01
2016/04/01
2016/05/02
2016/06/01
2016/07/01
2016/08/01
2016/09/01
2016/10/03
2016/11/01
2016/12/01
2017/01/04
2017/02/01
2017/03/01
2017/04/03
2017/05/01
2017/06/01
2017/07/03
2017/08/01
2017/09/01
2017/10/02
2017/11/01
2017/12/01
2018/01/04
2018/02/01
2018/03/01
2018/04/02
2018/05/01
2018/06/01
2018/07/02
2018/08/01
2018/09/03
2018/10/01
2018/11/01

Days

Be deposition
2(Bq/m )

29
28
29
30
32
29
31
31
30
34
27
35
28
28
30
30
31
30
33
29
30
32
29
34
28
29
31
31
30
30
31
31
32
29
30
34
28
28
33
28
31
32
29
31
31
30
30
34
28
28
32
29
31
31
30
33
28
31

460 ± 2133 ± 1337 ± 2172 ± 1220 ± 1
162 ± 1129 ± 1161 ± 139 ± 0.5
321 ± 2500 ± 21370 ± 4664 ± 2524 ± 2455 ± 2241 ± 2118 ± 1
204 ± 160 ± 1150 ± 1
208 ± 1156 ± 1378 ± 2652 ± 2943 ± 3537 ± 2125 ± 1130 ± 1
118 ± 1
10 ± 0.3
118 ± 1157 ± 1
164 ± 1156 ± 1487 ± 2643 ± 21010 ± 3
578 ± 2
246 ± 1185 ± 1156 ± 1
183 ± 1168 ± 194 ± 1128 ± 1365 ± 2908 ± 31036 ± 31367 ± 4772 ± 3253 ± 1232 ± 2308 ± 176 ± 176 ± 126 ± 0.4344 ± 2229 ± 1

7

Be concentration(Bq/L)
3.46 ± 0.017
1.94 ± 0.014
1.33 ± 0.008
1.58 ± 0.010
2.29 ± 0.011
1.44 ± 0.009
0.61 ± 0.004
0.49 ± 0.003
0.49 ± 0.006
1.55 ± 0.007
2.90 ± 0.015
2.11 ± 0.005
2.60 ± 0.009
2.29 ± 0.011
2.60 ± 0.011
1.24 ± 0.009
1.35 ± 0.010
1.31 ± 0.007
0.42 ± 0.004
1.27 ± 0.010
0.92 ± 0.005
1.66 ± 0.012
1.76 ± 0.008
2.26 ± 0.008
3.23 ± 0.011
2.68 ± 0.012
1.95 ± 0.018
0.85 ± 0.007
1.26 ± 0.011
0.07 ± 0.002
1.17 ± 0.008
1.09 ± 0.006
0.62 ± 0.004
0.97 ± 0.008
3.06 ± 0.014
2.99 ± 0.009
4.19 ± 0.014
2.65 ± 0.011
2.43 ± 0.013
1.38 ± 0.010
2.06 ± 0.015
1.77 ± 0.010
0.74 ± 0.006
0.46 ± 0.004
0.60 ± 0.004
1.15 ± 0.006
3.22 ± 0.011
3.17 ± 0.008
3.59 ± 0.013
2.70 ± 0.012
1.36 ± 0.007
1.27 ± 0.008
1.02 ± 0.006
0.85 ± 0.008
0.29 ± 0.004
0.25 ± 0.004
0.65 ± 0.004
2.59 ± 0.013

Precipitation Snowfall
(mm)
(mm)
128
69
252
109
96
113
213
330
79
207
173
649
256
229
175
195
87
156
141
118
227
94
215
289
292
200
64
173
81
153
101
143
264
160
159
215
241
219
101
167
59
104
227
206
215
318
282
375
312
286
187
219
244
89
258
102
527
89

47
35
20
0
0
0
0
0
0
0
0
126
31
57
15
0
0
0
0
0
0
0
0
0
86
44
9
0
0
0
0
0
0
0
0
5
63
56
12
0
0
0
0
0
0
0
0
26
181
197
0
0
0
0
0
0
0
0

11

12

YoshidaJ. Nucl. Radiochem. Sci., Vol. 24, 2024
7

Sampling information
Year

2019

2020

2021

Month
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3

Period2018/11/01
2018/12/03
2019/01/04
2019/02/01
2019/03/01
2019/04/01
2019/05/07
2019/06/03
2019/07/01
2019/08/01
2019/09/02
2019/10/01
2019/11/01
2019/12/02
2020/01/06
2020/02/03
2020/03/02
2020/04/01
2020/05/07
2020/06/01
2020/07/01
2020/08/03
2020/09/01
2020/10/01
2020/11/02
2020/12/01
2021/01/04
2021/02/01
2021/03/01-

2018/12/03
2019/01/04
2019/02/01
2019/03/01
2019/04/01
2019/05/07
2019/06/03
2019/07/01
2019/08/01
2019/09/02
2019/10/01
2019/11/01
2019/12/02
2020/01/06
2020/02/03
2020/03/02
2020/04/01
2020/05/07
2020/06/01
2020/07/01
2020/08/03
2020/09/01
2020/10/01
2020/11/02
2020/12/01
2021/01/04
2021/02/01
2021/03/01
2021/04/01

Days

Be deposition
2(Bq/m )

32
32
28
28
31
36
27
28
31
32
29
31
31
35
28
28
30
36
25
30
33
29
30
32
29
34
28
28
31

316 ± 2793 ± 3906 ± 3270 ± 1456 ± 2230 ± 1120 ± 1388 ± 2227 ± 1102 ± 181 ± 1277 ± 1
293 ± 1835 ± 3678 ± 2458 ± 2428 ± 2417 ± 2166 ± 1278 ± 2297 ± 274 ± 1252 ± 1
195 ± 1327 ± 21409 ± 41010 ± 3
835 ± 3325 ± 2

7

Be concentration(Bq/L)
4.03 ± 0.019
3.04 ± 0.010
5.87 ± 0.021
3.45 ± 0.019
3.74 ± 0.015
1.69 ± 0.006
1.36 ± 0.012
1.64 ± 0.008
1.20 ± 0.007
0.52 ± 0.005
1.26 ± 0.012
1.16 ± 0.006
3.76 ± 0.018
3.94 ± 0.010
2.65 ± 0.010
3.18 ± 0.015
2.79 ± 0.012
2.81 ± 0.009
1.84 ± 0.016
0.93 ± 0.005
0.83 ± 0.004
0.58 ± 0.006
0.95 ± 0.005
2.06 ± 0.012
2.18 ± 0.011
3.58 ± 0.008
2.70 ± 0.009
3.87 ± 0.014
2.08 ± 0.010

Precipitation Snowfall
(mm)
(mm)
78
261
154
78
122
136
88
237
189
195
64
240
78
212
256
144
154
148
90
298
360
126
264
95
150
394
374
216
157

0
19
20
3
3
0
0
0
0
0
0
0
0
0
0
8
0
0
0
0
0
0
0
0
0
46
146
51
0