干旱等级

类型

SPI

SPEI

0

无旱

−0.5 < SPI

−0.5 < SPEI

1

轻旱

−1.0 < SPI ≤ −0.5

−1.0 < SPEI ≤ −0.5

2

中旱

−1.5 < SPI ≤ −1.0

−1.5 < SPEI ≤ −1.0

3

重旱

−2.0 < SPI ≤ −1.5

−2.0 < SPEI ≤ −1.5

4

特旱

SPI ≤ −2.0

SPEI ≤ −2.0