等级 | 分类 | SPI |
0 | 接近正常 | −0.5 < SPI ≤ 0.5 |
1 | 轻旱 | −1.00 < SPI ≤ −0.5 |
2 | 中旱 | −1.50 < SPI ≤ −1.00 |
3 | 重旱 | −2.00 < SPI ≤ −1.50 |
4 | 极旱 | SPI ≤ −2.00 |