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The Mesosphere and Lower Thermosphere (MLT) is a critical atmospheric region ranging from 80–140 km in altitude. A main driver of momentum transport, density perturbations, temperature variations, and background winds in this region are atmospheric gravity waves which are not well accounted for in many models of the thermosphere and near-space region. Additionally, global circulation models that do include GWs fail to resolve small-scale activity ( $<$200 km). We utilize a hydroxyl (OH) airglow imager located in Poker Flat, Alaska (65°N 147°W) to leverage our active citizen science initiative, the Gravity Wave Zoo, expanding the breadth of available GW, aurora, and instability data over multiple seasons. We focus on a short-term study between 27 December 2023 and 4 February 2024 to statistically validate a subsample of this multi-year dataset, and report on recent Gravity Wave Zoo progress and accuracy, presenting a summary of overall participation and citizen classifications of GW, instability, and auroral events. We find citizen scientist classifications indicate GWs in 54.5%, aurora in 40.1%, and instabilities in 23.4% of subjects. We further propose future research directions enabled by this work and highlight the advantages of high temporal resolution data on the scale of weeks, months, and seasons. 

Equatorial Plasma Bubbles (EPBs) are a region of depleted ionospheric densities. EPBs are known to fluctuate both seasonally and day to day, and have been linked to changes in solar activity, geomagnetic activity, and seeding resulting from dynamics occurring at lower altitudes. Here, EPB activity is investigated over a 15-day period with overlapping coincident ground-based 630 nm oxygen airglow measurements, near-infrared hydroxyl mesospheric temperature mapper (MTM) measurements, and Rate Of change of Total Electron Content Index (ROTI) values. The data are compared with the Navy Global Environmental Model (NAVGEM) reanalysis over the same time period. It is found that several days with strong EPB activity coincided with the positive/northward meridional wind phase of the quasi-two-day wave (QTDW) in the mesosphere. These initial observations indicate correlations of the QTDW phase and the occurrence rates of EPBs, and suggest a need for further investigations to assess potential causal relationships that may affect the variability and prevalence of EPBs. 

School closures may reduce the size of social networks among children, potentially limiting infectious disease transmission. To estimate the impact of K–12 closures and reopening policies on children's social interactions and COVID-19 incidence in California's Bay Area, we collected data on children's social contacts and assessed implications for transmission using an individual-based model. Elementary and Hispanic children had more contacts during closures than high school and non-Hispanic children, respectively. We estimated that spring 2020 closures of elementary schools averted 2167 cases in the Bay Area (95% CI: −985, 5572), fewer than middle (5884; 95% CI: 1478, 11.550), high school (8650; 95% CI: 3054, 15 940) and workplace (15 813; 95% CI: 9963, 22 617) closures. Under assumptions of moderate community transmission, we estimated that reopening for a four-month semester without any precautions will increase symptomatic illness among high school teachers (an additional 40.7% expected to experience symptomatic infection, 95% CI: 1.9, 61.1), middle school teachers (37.2%, 95% CI: 4.6, 58.1) and elementary school teachers (4.1%, 95% CI: −1.7, 12.0). However, we found that reopening policies for elementary schools that combine universal masking with classroom cohorts could result in few within-school transmissions, while high schools may require masking plus a staggered hybrid schedule. Stronger community interventions (e.g. remote work, social distancing) decreased the risk of within-school transmission across all measures studied, with the influence of community transmission minimized as the effectiveness of the within-school measures increased.