The former adds a strong restriction to the latter , thus denoting that the subcritical instability easily occurs for a finite - amplitude disturbance in the real atmosphere . the new criterion has greatly improved the previous results 該判據(jù)表明,在實際大氣中對于有限振幅擾動容易產(chǎn)生斜壓亞臨界不穩(wěn)定,它大大地改進了以前的結(jié)果。