Effects of precipitation type on crash relative risk estimates in Kansas.

Crash relative risk estimates (CRREs) during rain, snow, sleet (i.e., ice pellets), and freezing rain are estimated using a matched-pair analysis in Kansas for the years 1995-2014.

Confronting the Challenge of Modeling Cloud and Precipitation Microphysics.

In the atmosphere, refers to the microscale processes that affect cloud and precipitation particles and is a key linkage among the various components of Earth's atmospheric water and energy cycles. The representation of microphysical processes in models continues to pose a major challenge leading to uncertainty in numerical weather forecasts and climate simulations. In this paper, the problem of treating microphysics in models is divided into two parts: (i) how to represent the population of cloud and precipitation particles, given the impossibility of simulating all particles individually within a cloud, and (ii) uncertainties in the microphysical process rates owing to fundamental gaps in knowledge of cloud physics.