Why is the air radiation dose rate very high at one point?
Air radiation dose rates temporarily increase associated with snowfall or rainfall.
ExplanationThis chart shows the daily maximum, average, and minimum of air radiation dose rate in Aomori City, Aomori Prefecture. Air radiation mostly comes from natural radiation from the ground and cosmic rays. When there is rainfall or snowfall, natural radionuclides in the atmosphere are “washed down” to the ground, and doses increase after rainfall or snowfall. When snow piles up high, the snow blocks radiation from the ground and doses reduce.
Why does the air radiation dose rate temporarily increase even without change in the weather?
Air radiation occasionally becomes highly affected by artificial radiation used for non-destructive inspection.