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Many STEM disciplines rely on experiential or applied-learning courses, camps, workshops, etc. to recruit and engage students. Field-based experiences are particularly important for those disciplines focused on readily observable Earth [...]

This paper describes a new severe weather laboratory exercise for an Introductory Weather and Climate class, appropriate for first and second year college students (including nonscience majors), that incorporates inquiry-based learning techniques. In the lab, students play the role of meteorologists making forecasts for severe weather. The exercise is designed to teach students how to identify the atmospheric conditions that promote severe weather and how to prepare a severe weather forecast. We utilize collaborative learning in the lab exercise where students are encouraged to work in teams to accomplish the class assignment. Working in teams teaches students about how modern interdisciplinary science is conducted, as well as creates accountability for students to learn the material and complete their share of the work. Our results show that important content knowledge is maintained in comparison with a traditional lab and that students found the new lab more engaging.

In the Southeastern U. S. there are Concentrated Animal Feeding Operations (CAFOs) that emit a variety of gases, including SO2. Sulfur is emitted as reduced sulfur compounds and can react in the atmosphere to produce SO2. It is expected that the concentration and spread of SO2 emissions from these sources would differ between wet and dry periods. In this research, SO2 emissions from locations representing CAFOs and its dispersion over the southeastern U.S. were simulated through sensitivity experiments using the Weather Research and Forecasting-Chemistry (WRF- Chem) model. Simulations were performed for dry periods and precipitation events that occurred over western Kentucky between July 7 and 13 July 2012. The study found that spatial coverage of SO2 dispersion originating from these locations was reduced during precipitation events and expanded during dry periods. The average concentration of SO2 over the study area was also higher during the breaks between precipitation events than during precipitation. The highest concentrations of SO2 exceeding 1,000 pptv remained within close range of the emission locations for the majority of the simulations, except for when local surface wind speeds were high. Most emissions from the locations remained limited to the surface and lower levels of the atmosphere (850 mb). [ABSTRACT FROM AUTHOR]

This study investigates convective and non‐convective high‐wind events (CWEs and NCWEs) across the eastern U.S. during a 43‐year climatological period (1973–2015) for spatial and temporal variations in wind speed and direction. Hourly surface wind observations were gathered from the National Centers for Environmental Information Data Center Integrated Surface Database (NCEI‐ISD). This dataset includes quality‐controlled wind observations from 391 first‐order weather stations in the eastern U.S. Findings show that high‐wind events (HWEs) meeting established National Weather Service criteria were most concentrated in the West North Central and South regions (High Plains) and fewer CWEs occurred during the study period compared to NCWEs. Gust CWEs increased significantly (1.95 days year−1) while sustained NCWEs decreased significantly (−0.58 days year−1). Mean wind directions were observed primarily in the southwest and northwest quadrants. Mean wind speed decreased at a statistically significant level for sustained CWEs, gust CWEs, and sustained NCWEs. Developing an extensive climatological understanding of convective and non‐convective high‐wind events is beneficial to mitigate damage and fatalities caused by these events. [ABSTRACT FROM AUTHOR]

This study examines the spatial and temporal characteristics of high‐wind events (HWEs) based on the National Weather Service high‐wind criteria for 391 first‐order weather stations in the eastern United States from 1973 to 2015. A geographical analysis on the frequency of sustained and gust HWEs shows that the highest occurrences were reported in the Great Plains and Great Lakes, while the lowest number of observations occurred in the Mid‐South and Southeast. Linear trends show that the yearly frequency of sustained and gust HWEs are significantly decreasing (−0.579 days/year) and increasing (0.943 days/year) respectively during the 43‐year study period. These trends do not persist when the HWE data are normalized (long‐term mean is removed from the yearly count), but shows a cyclical anomaly pattern for both sustained and gust winds. Overall, 90 and 82% of all sustained and gust HWEs occur from the northwest or southwest quadrant, but when interpreted from a spatial perspective the mean wind direction of HWEs can be classified into specific regional wind groupings. However, this persistent southwesterly wind direction has gradually shifted to a more southerly (northerly) orientation for sustained (gust) HWEs over the study period. [ABSTRACT FROM AUTHOR]

The purpose of this research is to investigate near surface mesoscale equivalent temperatures (TE) in Kentucky (located in east central USA) and potential land cover influences. TE is a measure of the moist enthalpy composed of the dry bulb temperature, T, and absolute humidity. Kentucky presents a unique opportunity to perform a study of this kind because of the observational infrastructure provided by the Kentucky Mesonet (www.kymesonet.org). This network maintains 69 research-grade, in-situ weather and climate observing stations across the Commonwealth. Equivalent temperatures were calculated utilizing high-quality observations from 33 of these stations. In addition, the Kentucky Mesonet offers higher spatial and temporal resolution than previous research on this topic. As expected, the differences (TE − T) were greatest in the summer (smallest in the winter), with an average of 35 °C (5 °C). In general, the differences were found to be the largest in the western climate division. This is attributed to agricultural land use and poorly drained land. These differences are smaller during periods of drought, signifying less influence of moisture. [ABSTRACT FROM AUTHOR]

The article presents an analysis of warm-season mesoscale convective complexes (MCCs) in subtropical South America (SSA). It investigates MCCs of the said area by illustrating their physical properties during the austral warm season of 1998-2007 in SSA. It reveals that MCCs in the region are long-lasting events with great potential for contributing to precipitation totals across the zone.