Question

Which is a period of abnormally high temperature

Answer 1

A definition based on Frich et al.'s Heat Wave Duration Index is that a heat wave occurs when the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by 5 °C (9 °F), the normal period being 1961–1990.[3]
A formal, peer-reviewed definition from the Glossary of Meteorology is:[4]
A period of abnormally and uncomfortably hot and usually humid weather.
To be a heat wave such a period should last at least one day, but conventionally it lasts from several days to several weeks. In 1900, A. T. Burrows more rigidly defined a “hot wave” as a spell of three or more days on each of which the maximum shade temperature reaches or exceeds 90 °F (32.2 °C). More realistically, the comfort criteria for any one region are dependent upon the normal conditions of that area. plzzz mark me brainliest ans