Effect of Landscape Modification on the Synoptic and Inland Patterns of Atmospheric River (AR) Events in the Western United States: Observational and Modeling Analysis.

This study addresses the following two important science questions: 1)" Have long term trends in landscape change modified the inland patterns of ARs that are responsible for occurrence of storms and flooding in the western US?", and 2)" What are the relative sensitivities of landscape modifications, particularly in the form of human-induced land-use/land cover (LULC) change, on the synoptic and inland patterns of atmospheric river (AR) events?" The first question was addressed through observational analysis of AR-related storms that occurred from 1970 to 2000. Thirty years (1970-2000) of daily precipitation data from the Global Historical Climatology Network (GHCN) were analyzed to obtain the highest intensity storm event for each decade. For each station and decade, anomalies of precipitable water and integrated vapor transport (IVT) were evaluated as first-hand indicators of the interdecadal synoptic …