Upturn and upsurge are synonyms for increase. They begin with the letter u.

• uncurl,
• unduly,
• unfurl,
• unhurt,
• unruly,
• unsung,
• unsure,
• untrue,
• unused,
• upturn,
• useful,

in short time natural disasters can destroy buildings, tear up roads and upturn normal life

The antonym for free fall is upturn. Free fall also has several synonyms such as dive, plummet, plunge, drop, and collapse.

The industry was in such a strong upturn that TSMC acquired the rival Worldwide Semiconductor Corporation in 2000 to keep up with the demand.