Bridgette's Title/Abstract:
Improving the Usability of Soil Temperature Information to Support Agricultural Decision Making
Soil temperature plays a major role in the agriculture industry as it affects management practices including planting and harvesting, soil and water conservation decisions, and crop rotations. Despite its importance to agriculture, there remains a dearth of soil temperature information in the United States. Soil temperature is monitored by multiple local- and state-level networks; however, few studies have attempted to use these observations to build a usable soil temperature climatology and prediction tool. We address this information gap in Illinois by developing a comprehensive, data-driven soil temperature climatology using decades’ worth of in situ observations from 19 sites that are part of the Illinois Climate Network and Water & Atmospheric Resources Monitoring (WARM) Program. In particular, we develop publicly available maps and figures of soil temperature averages and extremes, including probabilistic expectations of reaching critical temperature thresholds for agriculture, such as 50- and 60-degrees Fahrenheit. We also test a variety of spatial interpolation techniques to fill in data gaps between the 19 WARM stations in Illinois. Additionally, we construct a soil temperature prediction tool to produce subseasonal-to-seasonal forecasts. The soil temperature climatology and prediction tools will support agricultural decision making on seasonal to multi-year timescales in Illinois.
Sophia's Title/Abstract:
Use of Airborne Lidar For Boundary Layer Entrainment Zone Observations
Entrainment processes in the cloud-topped convective boundary layer are known to lead to boundary layer heating, most often drying, and changing concentrations of constituent gases and particles. However, such entrainment processes are notoriously difficult to observe and to accurately simulate. During lake effect snow events, the clouds fill the upper layers of the convective boundary layer; therefore, it might be anticipated that entrainment processes could have large impacts on lake effect formation and snowfall production overall. Using data taken during the Ontario Winter Lake Effect Systems (OWLeS) project provided by the University of Wyoming Cloud LIDAR (WCL) on 17 intensive operations periods (IOPs), we have documented spatial variations in the top of the lake-effect clouds, indicative of the boundary layer top, over Lake Ontario and surrounding land areas. The WCL cannot penetrate thick lake effect clouds, resulting in a thin layer of high backscatter with markedly lower backscatter values below. The backscatter variability is used to determine how cloud tops vary spatially along the flight leg, which gives an idea of the depth of the entrainment zone. 264 one-minute observations of the boundary layer top observations were identified when the UWKA flew mostly horizontal above the lake-effect cloud top. For each, average boundary layer top height and its variability have been calculated, with the intent of relating these factors to environmental conditions within and above the entrainment zone. Results indicate that the boundary layer top behaves much like is expected for convective boundary layers (CBL). Surprisingly, the lake effect cloud tops only penetrate the base of the entrainment zone.
