３か月ごとの値
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八丈島（東京都) 1981年（３か月ごとの値） 詳細（日照・雪・その他）
| 月 | 日照時間(h) | 全天日射量 (MJ/㎡) | 雪(cm) | 雲量 | 大気現象 | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 合計 | 日照率 | 各階級の日数 | 降雪 | 各階級の日数（降雪） | 最深積雪 | 各階級の日数（最深積雪） | 平均 | 各階級の日数 | 雪日数 | 霧日数 | 雷日数 | ||||||||||||||||||
| 不照 | 日照率 ≧40% | 平均 | 合計 | 日合計の最大 | ≧3cm | ≧5cm | ≧10cm | ≧20cm | ≧50cm | ≧100cm | 値 | 日 | ≧0cm | ≧1cm | ≧5cm | ≧10cm | ≧20cm | ≧50cm | ≧100cm | ＜1.5 | ≧8.5 | ||||||||
| 値 | 日 | ||||||||||||||||||||||||||||
11～1 | 425.6 | 45 | 3 | 52 | 17.2 | 0 | 0 | 01/22* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 12/29* | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 6.8 | 2 | 22 | 3 | 0 | 11 |
12～2 | 397.6 | 43 | 4 | 49 | 12.6 | 2 | 2 | 02/27 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 02/27 | 3 | 1 | 0 | 0 | 0 | 0 | 0 | 7.5 | 0 | 31 | 6 | 0 | 12 |
1～3 | 393.7 | 40 | 11 | 46 | 9.7 | 2 | 2 | 02/27 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 02/27 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 7.8 | 0 | 36 | 4 | 0 | 5 |
2～4 | 416.7 | 39 | 14 | 43 | 11.6 | 2 | 2 | 02/27 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 02/27 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 7.7 | 0 | 42 | 3 | 0 | 3 |
3～5 | 503.0 | 42 | 15 | 50 | 14.2 | 0 | 0 | 04/17 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.4 | 0 | 38 | 0 | 0 | 2 | |
4～6 | 510.4 | 41 | 15 | 48 | 16.0 | 0 | 0 | 04/17 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.4 | 0 | 41 | 0 | 3 | 2 | |
5～7 | 569.7 | 44 | 12 | 53 | 17.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.5 | 0 | 40 | 0 | 3 | 7 | ||
6～8 | 561.6 | 44 | 8 | 51 | 17.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.6 | 0 | 43 | 0 | 3 | 10 | ||
7～9 | 543.6 | 45 | 5 | 52 | 16.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.7 | 0 | 45 | 0 | 0 | 9 | ||
8～10 | 483.7 | 43 | 9 | 51 | 13.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.4 | 3 | 44 | 0 | 0 | 5 | ||
9～11 | 399.4 | 39 | 14 | 48 | 10.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.4 | 3 | 41 | 0 | 0 | 3 | ||
10～12 | 407.9 | 42 | 11 | 51 | 9.0 | 0 | 0 | 12/16* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.6 | 4 | 27 | 0 | 0 | 5 | |