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Far infrared (FIR) emission from the Earth's polar regions has become an area of increasing scientific interest and value. FIR emission is important for understanding Earth's radiative balance and improving global climate models, especially in rapidly changing Arctic conditions. Far‐infrared emission from Earth is not currently being monitored from space, except as part of broadband emission channels of Earth radiation budget measurements like those from the CERES project, and only limited measurements in the FIR spectrum exist. The Absolute Radiance Interferometer (ARI), developed as a prototype of the infrared spectrometer for CLARREO at the University of Wisconsin‐Madison, Space Science and Engineering Center, measures absolute spectrally resolved infrared (IR) radiance from 200 to 2,000 cm−1 (or 5–50 μm) at 0.5 cm−1 resolution with high accuracy (<0.1 K 3‐sigma brightness temperature at scene temperature). This instrument was taken into the field in Madison, Wisconsin, USA, during the winters of 2021 and 2022, where the weather can reach polar‐like conditions to measure high spectral resolution radiances of various sample types. Sample materials included water, snow, ice, evergreen leaves, dry grass, and sand, all characteristic of high latitude regions. Radiances collected from both a sky view and the sample view in clear‐sky conditions were used to retrieve FIR emissivity. This paper describes the ARI instrument configuration and capability for ground‐based measurements in the FIR region, and documents retrieved emissivities of various analyzed samples. The retrieved emissivity results are publicly available, and comparisons are made to simulated emissivity estimates. Key Points: Absolute Radiance Interferometer used to obtain high spectral resolution far infrared radiation measurements in semi‐controlled environmentsRadiation measurements of the sky and samples, including snow, water, ice, sand, and vegetation, allowed for retrieval of sample emissivityThe retrieved far infrared emissivity spectra and radiance measurements are available for model intercomparisons and other uses [ABSTRACT FROM AUTHOR]

High spectral resolution infrared sounders are an integral component of the global observing system and are used in a broad range of applications. This is enabled by their high accuracies which are ensured by rigorous calibration/validation activities. One of these activities is the post‐launch intercomparison with other high spectral resolution infrared sounders using simultaneous nadir overpasses (SNOs). This paper introduces a novel application of the previously developed SNO methodology by including time difference histogram symmetrization and a spatial sampling uncertainty. Where possible, radiometric measurement uncertainties are included and propagated through the statistics. Comparisons of Atmospheric Infrared Sounder (AIRS), METOP‐A/B/C Infrared Atmospheric Sounding Interferometer (IASI), and Cross‐track Infrared Sounder (CrIS) from 1 October 2019, to 1 October 2020, are analyzed. Results show AIRS and IASI differences as well as CrIS and AIRS differences are generally less than 0.4 K across the spectrum, and CrIS and IASI differences are generally less than 0.25 K. Comparison of the Suomi National Polar‐Orbiting Partnership and NOAA‐20 CrIS instruments via IASI and AIRS shows differences are generally less than 0.1 K across all bands and that the two CrIS instruments statistically agree within their radiometric uncertainties except for the narrow 2,370 cm−1 region where artifacts due to brightness temperature conversion are prone to occur. Plain Language Summary: One of the primary sources of information used to monitor Earth's weather patterns are satellite based meteorological instruments that measure radiation in the infrared region with high spectral resolution. Agencies worldwide use data from these types of instruments to provide input into weather prediction models. The long term data sets are also very valuable for multi‐decadal climate studies. To ensure the value of these data, the instruments need to be properly calibrated using external references. This paper details and expands upon the previously established methodology of one commonly used calibration technique—called SNOs. This method compares nadir‐viewing data from different instruments measuring radiation coming from the same mass of atmosphere in time and space. Introduced in this paper are two additions to the methodology: (a) a symmetrization of the time differences between when the instruments measure the specific air mass, and (b) an uncertainty estimate on the comparison based on the spatial coincidence of the measurements. Results from this methodology demonstration show how well the current suite of satellite‐based instrumentation measuring infrared radiation at high spectral resolution agree with each other. Key Points: Simultaneous nadir overpass comparisons include time difference symmetrization, spatial sampling uncertainty, and Cross‐track Infrared Sounder (CrIS) radiometric uncertaintyDifferences between Suomi National Polar‐Orbiting Partnership (SNPP) CrIS and NOAA‐20 CrIS are generally less than 0.1 K and within combined radiometric measurement uncertaintiesDifferences between Atmospheric Infrared Sounder (AIRS) and CrIS or AIRS and Infrared Atmospheric Sounding Interferometer (IASI) generally less than 0.4 K, differences between CrIS and IASI generally less than 0.25 K [ABSTRACT FROM AUTHOR]

A study was conducted to analyze the influence of postdeposition annealing with an d without a magnetic field on the crystallographic texture of Terfenol-D thin films. It was forecast that the (111) textured films would enhance magnetostrictive strains attainable for device applications. Experimental results indicated that the presence of magnetic field parallel to the film plane during annealing of samples on terbium substrates supports in-plane orientation of (220) planes of RFe2 phase.

The annealing behavior of amorphous terfenol-D thin films is examined in this work. Amorphous thin films were prepared by DC magnetron sputter deposition from alloy targets. Differential scanning calorimetry of these films was performed in the temperature range 100-800 [degrees] C. Based on DSC data annealing experiments were performed at 400, 550, 575, 600 and 650 [degrees] C. X-ray diffraction shows R[Fe.sub.2] phase is formed when samples are annealed at 575-600 [degrees] C. Other phases observed are Fe and rare earth oxide.