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The need for high precision measurements of vertical winds with uncertainties on the scale of 3–5 m ${\text{s}}^{-1}$and a temporal cadence of 1–2 min to achieve detection of gravity wave (GW) structure has made it exceedingly difficult to study the response of the thermosphere to the propagation of GW activity. Herein we present subauroral, midlatitude thermospheric wind and temperature observations using redline 630 nm measurements obtained with a 15 cm narrow field Fabry-Pérot Interferometer (FPI), named the Hot Oxygen Doppler Imager (HODI). These measurements were obtained in a first light campaign at Jeffer Observatory ( $41.03°$N, $74.83°$W) located in Jenny Jump State Forest in northwestern New Jersey. The heightened sensitivity of HODI enables analysis of observations with uncertainties of approximately 3–5 m ${\text{s}}^{-1}$for vertical wind speeds and 10–15 K for temperatures for 2-min exposures. Data was collected during periods of both geomagnetically quiet and active conditions, and GW structures were seen in both data sets. One detailed observation, taken the night of 25 July 2022, enabled the $\approx 90°$phase shift between vertical winds and temperatures to be inferred, as per standard GW polarization relations with weak viscous dissipation. However, most other observations are found to have little correlation between the two series of temperature and vertical wind. We interpret this to be a result of the propagation and interaction of multiple GW events superimposed upon one another. Wave-like structures in the ionosphere observed in differential total electron count maps, or traveling ionospheric disturbances (TIDs), are often related to GW induced processes, and we provide comparisons of selected wave events observed by HODI to TIDs. These results suggest in a general sense that a relationship may exist between wave fluctuations seen in both the neutral atmosphere and the ionosphere. However, we suggest that the 35–70 km vertical extent of the 630 nm nightglow layer combined with an environment of multiple GW events with differing propagation speeds and vertical wavelengths may have the effect of diminishing or eliminating possible existing temperature and vertical wind correlation. 

Abstract. Light transmission into bare glacial ice affects surfaceenergy balance, biophotochemistry, and light detection and ranging (lidar)laser elevation measurements but has not previously been reported for theGreenland Ice Sheet. We present measurements of spectral transmittance at350–900 nm in bare glacial ice collected at a field site in the westernGreenland ablation zone (67.15∘ N, 50.02∘ W). Empirical irradianceattenuation coefficients at 350–750 nm are ∼ 0.9–8.0 m−1 for ice at 12–124 cm depth. The absorption minimum is at∼ 390–397 nm, in agreement with snow transmissionmeasurements in Antarctica and optical mapping of deep ice at the SouthPole. From 350–530 nm, our empirical attenuation coefficients are nearly1 order of magnitude larger than theoretical values for optically pureice. The estimated absorption coefficient at 400 nm suggests the ice volumecontained a light-absorbing particle concentration equivalent to∼ 1–2 parts per billion (ppb) of black carbon, which is similar topre-industrial values found in remote polar snow. The equivalent mineraldust concentration is ∼ 300–600 ppb, which is similar to values forNorthern Hemisphere warm periods with low aeolian activity inferred from icecores. For a layer of quasi-granular white ice (weathering crust)extending from the surface to ∼ 10 cm depth, attenuationcoefficients are 1.5 to 4 times larger than for deeper bubbly ice. Owing tohigher attenuation in this layer of near-surface granular ice, opticalpenetration depth at 532 nm is 14 cm (20 %) lower than asymptoticattenuation lengths for optically pure bubbly ice. In addition to thetraditional concept of light scattering on air bubbles, our results implythat the granular near-surface ice microstructure of weathering crust isan important control on radiative transfer in bare ice on the Greenland IceSheet ablation zone, and we provide new values of flux attenuation,absorption, and scattering coefficients to support model development andvalidation. 

Process safety is at the heart of operation of many chemical processing companies. However, the Chemical Safety Board (CSB) has still documented over 800 investigations of process safety failures since the year 2000. While not all of these incidents were severe, some did lead to employee injuries or death and environmental harm. As a result, chemical engineering companies are increasingly dedicated to process safety through training programs and detailed vigilance as part of their operations practice. AIChE and OSHA also offer courses in process safety to help support the industry. These efforts illustrate the paramount importance that chemical engineering graduates have an appreciation and understanding of process safety as they transition from their degree program into industrial positions. Previous studies have shown that despite difficulties due to course load constraints, process safety has been incorporated into chemical engineering curriculum through either the addition of new courses, incorporation of the content within existing classes, or a combination of the two methods. A review performed in Process Safety Progress suggested that a key step for departments moving forward is to perform an assessment of the process safety culture within their institution in order to determine how faculty and students view process safety. An issue with completing this task is the lack of assessment tools that can be used to determine how students are developing their understanding of process safety decision making. This observation led to the development of the Engineering Process Safety Research Instrument (EPSRI). This instrument is modeled after the Defining Issues Test version 2 (DIT2) and the Engineering Ethical Reasoning Instrument (EERI). Similar to these instruments, the EPSRI provides dilemmas, three decisions, and 12 additional considerations that individuals must rate based on their relative importance to their decision making process. The dilemmas developed in the EPSRI are based on case studies and investigations from process safety failures that have occurred in industry to provide a realistic context for the decision making decisions that engineers may be faced with upon employment. The considerations provided after the scenario are derived to reflect pre-conventional, conventional, and post-conventional decision making thinking as described by Kohlberg’s Moral Development Theory. Pre-conventional decision making thinking focuses particularly on what is right/wrong or good/bad from an individual level, whereas post-conventional thinking seeks to determine what is correct from moral and value perspectives at the society level. This WIP paper describes the content validity study conducted while developing the EPSRI. Dilemmas were examined by context experts including professionals in the process industry, chemical engineering departments, and learning sciences field. Content experts reviewed the dilemmas and determined whether they represented accurate examples of process safety decision making that individuals may face in real-world engineering settings. The experts also reviewed the 12 considerations for each dilemma for their accuracy in capturing pre-conventional, conventional and post-conventional thinking. This work represents the first step in the overall instrument validation that will take place over the next academic year.