Collaborative Research: Maritime to Inland Transitions Towards ENvironments for Convection Initiation (MITTEN CI)

The goal of the Maritime to Inland Transitions Towards ENvironments for Convection Initiation (MITTEN-CI) campaign is to develop the most thorough understanding to date of transitions in near-surface thermodynamic and wind profile structure due to inland movement of marine air in the Great Lakes coastal environment, and resultant impacts on thunderstorm development. Understanding such transitions and their implications for thunderstorms has substantial broader impacts, given the significant portion of the human population that lives in coastal areas. Hypotheses are developed to target novel aspects of near-shore thunderstorm development and evolution of near-surface profiles of temperature, humidity, and wind that have received relatively little attention and enable operations under a wide range of background weather patterns, resulting in a high probability of success in the campaign’s goals. The MITTEN-CI campaign will result in an extensive dataset that characterizes the temporal evolution of over-lake thermodynamic and kinematic profiles using Uncrewed Aircraft Systems (UAS), in addition to thorough sampling of boundary layer spatial and temporal variability over land using instrumentation along a 120 km shore-perpendicular transect with six flux towers, two mobile mesonets, multiple radiosonde launch sites, a Doppler LiDAR, and two mobile Ka-band Doppler radars. These data will enable hypothesis testing that will result in new knowledge of processes across a range of scales that result in convection initiation (CI) or failure thereof in midlatitude coastal regions. Specific aspects of coastal convective environments and CI to be investigated include development of lake-breeze MAHTEs (mesoscale airmasses with high theta-e), i.e., instability maxima on the cool side of lake-breeze fronts (LBFs), the potential for diffuse LBFs to exist embedded within synoptic-scale onshore flow and influence CI, LBF misovortex influence on CI both independently and through interactions with horizontal convective rolls, RKW theory’s relation to LBF CI, and the influence of entrainment on LBF thermodynamics, structure, and propagation. Significant new knowledge of processes related to MAHTE development is expected and will inform broader research on MAHTE development in other types of frontal boundaries which are more difficult to study without a nomadic campaign. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.