natural calamity; natural disaster
Refers to catastrophic natural events such as earthquakes, floods, or volcanic eruptions. Somewhat formal or written-style.
This region has been struck by major natural calamities in the past.
地変に備えて防災訓練を行う。
We conduct disaster drills to prepare for natural calamities.
natural disaster; calamity of nature
Compound of 地 (chi, 'earth, ground') and 変 (hen, 'change, unusual event'). The exact historical derivation is uncertain, but the word has been used in written Japanese to refer to terrestrial upheavals and natural disasters.