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In November 2022 the OASIS measurement system (Observations of Airglow with Spectrometer and Imager Systems) for airglow observations was set up right next to ESO's Very Large Telescope (VLT) in Chile. It aims for observing OH nightglow with high temporal resolution in order to investigate natural hazards emitting waves (e.g. tsunamis, earthquakes, storms). Furthermore, general middle atmospheric dynamics are studied in greater detail above the Andes region, among others to develop precise methods for providing valuable near-real time data about the airglow variability for the astronomic observation scheduling of the VLT. The OASIS system consists of three airglow instruments, one spectrometer with a pan-tilt mechanism to observe selected events at any direction on the nightsky on demand, and two imager systems, an allsky camera and a narrower field-of-view camera. All three instruments have a high temporal resolution of (15s, 2s, and 1.5s, respectively) and observe the short-wave infrared part of OH nightglow around 1.5µm to 1.6µm. The good observation conditions at the astronomic site with clear sky conditions throughout the entire year give a very good data coverage allowing for unique analyses on a statistical basis as well as on specific case studies e.g. of waves emitted by natural hazard events propagating up to the mesosphere and lower thermosphere. We present the OASIS measurement system, its mission objectives, and first results from the first nine months of observations concerning general gravity wave activity above the Andes, stunning gravity wave events, and extraordinary variations of airglow intensity., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Adaptive Force (AF) characterizes the capability of the neuromuscular system to adapt to external forces. The aim was to measure the effects of different olfactory inputs on the AF of the hip and elbow flexors, respectively. The AF of 10 subjects was examined manually by experienced testers while smelling at sniffing sticks with neutral, pleasant or disgusting odors. The reaction force and the position of the tested limb were recorded by a handheld device. The results show, inter alia, a significantly lower maximal isometric AF and a significantly higher AF at the onset of oscillations with disgusting odor compared to pleasant or neutral odors (p

Thermal infrared (TIR) spectra of Earth surface materials are used in a wide variety of applications. These applications can fall into either of two groups: (a) where the TIR emissivity spectra themselves are the primary interest, and are used to determine the chemical/physical parameters of minerals and rocks, soil, vegetation and man-made materials, or (b) where the primary interest is in the temperature of the objects under study, and where emissivity spectra are required inorder to best determine kinetic from radiant temperature. Unlike visible-near infrared (VNIR) and shortwave infrared (SWIR) instruments, TIR spectroscopy instrumentation often requires customization in order to acquire reliable and reproducible data, making thermal spectroscopy a potentially complex process. Within this chapter we intend to provide a simple starting point for the new user of thermal infrared spectroscopy, and a synoptic overview of the technique for the more experienced practitioner. We discuss the theoretical background, give examples of instrument setups and provide typical measurement scenarios for a number of land applications.

This is a case example of mineral mapping of unaltered and altered rocks at the Cuprite mining district, southwestern Nevada using the Spatially Enhanced Broadband Array Spectrograph System (SEBASS), a thermal infrared hyperspectral sensor that collects radiance measurements in the mid-wave infrared and thermal infrared portions of the electromagnetic spectrum. Cuprite, Nevada has been a test bed for a variety of multispectral and hyperspectral sensors that have predominantly covered the visible through short-wave infrared portion of the electromagnetic spectrum. In 2008, 20 SEBASS flight lines were collected at an average altitude of 4,735 m yielding an average 3.35 m ground sample distance (GSD).

Vegetation cover is one of the key parameters for monitoring the state and dynamics of ecosystems. African semi-arid landscapes are especially prone to degradation due to climate change and increased anthropogenic impact on different spatial and temporal scales. In this study, a multiscale method is applied to monitor vegetation cover by deriving sub-pixel percentages of woody vegetation, herbaceous vegetation and soil. The approach is comparatively applied to two semi-arid savannas, one in Namibia and one in Kenya. The results in eastern and southern Africa demonstrate the applicability of the method to different semiarid ecosystems and to different types of remote sensing data. The presented analysis could show that continuous cover mapping is a highly suitable concept for semi-arid ecosystems, as these show gradual transitions rather than distinct borders between land cover types. Different spatial patterns of vegetation cover depending on land use practices and intensities could be revealed.

Uncertainties in the carbon budget of high latitude ecosystems are partly due to difficulties in assessing the spatially and temporally highly variable methane emissions of permafrost soils. CH4 contributes significantly to global warming. Arctic regions are most critically influenced by a changing climate. Modeling approaches are important tools to determine CH4 fluxes of arctic environments. We present two process-based models to calculate methane emission from permafrost soils. Model forcing consists of ECMWF (European Center for Medium-Range Weather Forecasts) meteorological data which are validated against field measurements. Auxiliary input data is derived from satellite imagery and field measurements. A MERIS-FR land classification scheme is used to upscale emissions. Model results are validated using methane flux measurements on the landscape and small scale carried out in 2006 in the Lena Delta (72°N, 126°E) by Alfred Wegener Institute for Polar and Marine Research. The study site is characterized by arctic tundra ecosystems and continuous permafrost.

Airborne imaging spectrometers have a history of about 20 years starting with the operation of AIS in 1982. During the following years, many other instruments were built and successfully operated, e.g., AVIRIS, CASI, DAIS-7915, and HyMap. Since imaging spectrometers cover a spectral region with a large number of narrow contiguous bands they are able to retrieve the spectral reflectance signature of the earth allowing tasks such as mineral identification and abundance mapping, monitoring of vegetation properties, and assessment of water constituents. An essential prerequisite for the evaluation of imaging spectrometer data is a stable spectral and radiometric calibration. Although a considerable progress has been achieved in this respect over the last two decades, this issue is still technically challenging today, especially for low-to-medium cost instruments. This paper introduces a new airborne imaging spectrometer, the ARES (Airborne Reflective Emissive Spectrometer) to be built by Integrated Spectronics, Sydney, Australia, and co-financed by DLR German Aerospace Center and the GFZ GeoResearch Center Potsdam, Germany. The instrument shall feature a high performance over the entire optical wavelength range and will be available to the scientific community from 2006 on. The ARES sensor will provide 150 channels in the solar reflective region (0.47-2.42 µm) and the thermal region (8.1-12.1 µm). It will consist of two co-registered optical systems for the reflective and thermal part of the spectrum. The spectral resolution is intended to be between 12 and 16 nm in the solar wavelength range and should reach 150 nm in the thermal range. ARES will be used mainly for environmental applications in terrestrial ecosystems. The thematic focus is thought to be on soil sciences, geology, agriculture and" forestry. Limnologic applications should be possible but will not play a key role in the thematic applications. For all above mentioned key application scenarios, the spectral response of soils, rocks, and vegetation as well as their mixtures contain the valuable information to be extracted and quantified. The radiometric requirements for the instrument have been modeled based on realistic application scenarios and account for the most demanding requirements of the three application fields: a spectral bandwidth of 16 nm in the 0.47-1.8 (µm region, and 12 nm in the 2.02 - 2.42 µm region. The required noise equivalent radiance is 0.05, 0.03, and 0.02 Wm-2 sr-1µm-1 for the spectral regions 0.47- 0.89 µm, 0.89 - 1.8 µm, and 2.02 - 2.42 µm, respectively. In the thermal region similar simulations have been carried out. Results suggest a required noise equivalent temperature of 0.05 K for the retrieval of emissivity spectra in the desired accuracy. Nevertheless, due to system restrictions these requirements might have to be reduced to 0.1 K in the wavelength range between 8.1 and 10 µm and 0.1-0.2 K from 10 to 12.1 µm.