A pulse flow is a surge of water that periodically flows through a river — normally as the result of natural events such as spring storms or melting snow. (aaas.org)
However, global warming is caused by natural events and human that is believed to contribute to increases in average temperature. (studentsassignmenthelp.com)
Bring pets indoors at the first sign of a storm or other natural event or human disaster. (cesarsway.com)