Drought and Wetness Variability and the Respective Contribution of Temperature and Precipitation in the Qinghai-Tibetan Plateau

Table 1

Drought and wetness classification based on the SPEI value [17, 28, 30].

Category	SPEI value
Extremely wet	SPEI ≥ 2
Moderately wet	1.5 ≤ SPEI < 1.99
Slightly wet	1 ≤ SPEI < 1.49
Near normal	−0.99 < SPEI < 0.99
Mild drought	−1.49 < SPEI ≤ −1
Moderate drought	−1.99 < SPEI ≤ −1.5
Extreme drought	SPEI ≤ −2