In the next ten years, forecasting of aerosol ground concentrations of PM_2.5 and ozone are expected to become part of the US weather forecasting system. It will be important to verify that the forecast models of these species are accurate in both the temporal and spatial domain. Unlike validation of meteorological parameters where radiosoundings and satellite retrievals of these variables are common, there are no routine observations of PM_2.5 and ozone profiles in the troposphere available at this time. Surface observations of aerosols and ozone are particularly sensitive to the PBL vertical structure and model validation can be especially challenging when only surface data are available. Along with an number of collaborators, the authors have described a new network, the Regional East Atmospheric Lidar Mesonet (REALM), which has potential to address data requirements for validation of these model developments.

This presentation will describe the available lidars in the network, the species that they will be capable of profiling and the current status of the systems in terms of comparibility between sites. Examples of coincident data taken in Greenbelt, MD and Baltimore MD within the Washington-Baltimore urban corridor will be shown which indicate the capability of the network to address issues of timing of arrival of aerosol events and their spatial scale.