Understanding Diurnal Variability of Precipitation through Observations and Models (UDVPOM)
The variability of precipitation is an immensely important subject because of its direct control on and response to the atmospheric and surface water-energy cycles, which strongly govern weather and climate. Precipitation variability takes place across the complete range of scales up to the very high local-diurnal scales down to the very low global-decadal and longer scales. The diurnal variability of precipitation is a multifaceted global phenomenon with embedded regional phenomena far more complex than can be readily explained with generalized causal factors. For example, the generally dominant late-night to early-morning oceanic rainfall peak is often accompanied by a secondary afternoon peak, while the generally dominant mid- to late-afternoon continental rainfall peak can be accompanied or even replaced by a secondary early-morning peak. Over the earth's many regions, there are a host of mechanisms at work in producing diurnal rainfall processes, no one of which can be used to explain the entire process. Instead, it appears that for a given region, a mixture of mechanisms are often at play, whose individual components control smaller-scale diurnal modes, ultimately working together to describe the mean global process. The topic of this special collection is the diurnal variability of precipitation, cast in the framework of "Understanding Diurnal Variability of Precipitation through Observations and Models" (UDVPOM). Since the advent of high-quality, multiyear, and globally distributed observations of precipitation from spaceborne sensors, there has yet to be a focused study concerning the topic of the diurnal variability of precipitation. This special collection of the Journal of Climate contains 11 papers that seek to bring about this focus. The full collection preface can be viewed here.
Song Yang and Eric A. Smith