Science Source

Linkage Between Hourly Precipitation Events and Atmospheric Temperature Changes over China during the Warm Season

States measurement of precipitation on a finer temporal scale, for example, hourly rainfall, better reflects the essential physical characteristics of precipitation and hence is important in many fields
States changes in the characteristics of short-term precipitation events are of interest because of the potential hydrologic impact of these events, including flash floods, erosion, landslides, debris flows, and urban water-logging
States a warmer atmosphere tends to hold more moisture and, within the context of global warming, induces extreme rainfall events with higher rainfall intensity
States a warmer atmosphere tends to hold more moisture and, within the context of global warming, induces extreme rainfall events with higher rainfall intensity; states the Clausius–Clapeyron (C-C) relation indicates that the rate of increase in atmospheric moisture-holding capacity is approximately 7% per degree Celsius of warming; states previous studies have reported that the intensity of extreme daily rainfall in a global climate model increases at the same rate; however, the intensity of hourly precipitation has been demonstrated to exhibit a “super C-C” relationship with rises in temperature, featuring a rate of increase that exceeds 7% per degree Celsius of warming
Study aims to: (1) identify temporospatial changes in the characteristics of hourly precipitation over China; (2) quantify the rate of change of extreme hourly precipitation with temperature; and (3) evaluate the influence of hourly precipitation on temperature variations
Focuses on the variations during the warm season (May–September), since the climate in China is dominated by the East Asia summer monsoon with summer precipitation accounting for about 70% of the annual rainfall
Investigates trends in the frequency of light, moderate, heavy, and extreme precipitation events over nine different river basins
Divides all hourly precipitation events across China into four categories: light (<5 mm/h), moderate (5–10 mm/h), heavy (10–20 mm/h), and extreme (>20 mm/h)
Compares the changes in mean precipitation amount, intensity, and frequency in these four categories between the periods 1991–2001 and 2002–2012
Finds the dependency of hourly precipitation on daily mean temperature in the warm season at most stations was approximately 4–6% per degree Celsius for the 75th percentile of precipitation and that only 41% (240/580) and 47% (274/580) of all stations showed regression slopes slightly greater than the C-C rate of 7% per degree Celsius for the 99th and 99.9th percentiles of precipitation, respectively
Results show that, at most stations, rainfall intensity increased with temperature up to a maximum and then decreased with temperature beyond that maximum

Linkage Between Hourly Precipitation Events and Atmospheric Temperature Changes over China during the Warm Season

Related Content