Through the monthly comparison between RVCI and VCI during the 22 years, it is shown that RVCI remarkably improves VCI to better reflect the perennial drought condition of the arid areas.

• 通过对22年来逐月RVCI与VCI的对比，RVCI客观地反映了干旱气候区常年干旱特点，较VCI有显著改进。