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Abstract. The development of small, high-performance instruments to receive Global Positioning System (GPS) signals has created an opportunity for active remote sounding of the Earth's atmosphere by radio occultation techniques. A prototype demonstration of this capability has been provided by the GPS Meteorology (GPS/MET) experiment. Although it was shown that high vertical resolution profiles of atmospheric refractivity, temperature, and geopotential height of constant pressure levels can be derived from the GPS measurements, with high accuracy under many circumstances, many issues remain. These include the existence of multipath propagation, the ambiguity between water vapor and temperature in moist regions of the atmosphere, and the difficulty in retrieving an accurate refractivity profile from the GPS refraction angle measurements over regions where the horizontal gradient of the refractivity is large. The aim of this paper is to begin the development of a methodology for incorporating the GPS "raw" measurements (refraction angles) directly into numerical weather analysis and/or prediction systems in order to alleviate the above mentioned problems. First, a ray-tracing observation operator that links the atmospheric state to the GPS refraction •rngle measurements is developed, the physics and numerics involved are described, and the simulated refraction angles, based on the NOAA National Centers for Environmental Prediction (NCEP) global analysis, are compared with the observed GPS/MET refraction angle measurements. Second, the tangent linear and adjoint of the ray-tracing operator are developed. These three operators are required for the direct use of GPS refraction angle measurements in a variational data analysis system. A single observation experiment reveals that the direct use of GPS refraction angles in a variational analysis causes changes in the temperature and specific humidity fields that are not limited to the occultation location but in an elongated band of _+300 km in its occultation plane. On o--levels, changes from the use of one GPS occultation occur in an area of about 600 km x 600 km large which is centered around the ray perigee point. Finally, the advantages and disadvantages are discussed for the use of the GPS refractivities versus refraction angles. Errors made by using local estimates of refractivity are also assessed.

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PurposeTravellers who love to try different foods and who frequently follow up on food-related news and topics consider themselves to be “foodies”. The main aim of this research was to identify the relationships among food consumption motivations, experiential values and well-being of foodies.Design/methodology/approachA questionnaire survey was distributed to foodies from the Chinese mainland, Hong Kong and Macao in March–May 2019 who were aged 18 and above and who had visited Taiwan within the prior two years. Some 480 valid responses were received based on intercepts at airports and the data, based on a conceptual model, were analysed through structural equation modelling (SEM).FindingsThree paths among the key variables showed significant and positive relationships. Additionally, the mediating effect of food experiential values on emotions and well-being was identified.Research limitations/implicationsThe findings provide insights for food and hospitality scholars and the related literature since “foodie” is a rather new concept that is lacking in sufficient empirical and conceptual research. The research examines the relationships among experiential values, motivations and emotions and their influences on the well-being of foodies. In past studies on food consumption motivations and emotions, food experiential values were not included as a variable of potential influence. The research subjects were confined to foodies from the Chinese mainland (including Hong Kong and Macao) who were in Taiwan. Hence, the generalisation based on the sample may be limited.Practical implicationsThis research produces useful information on the behaviour of Chinese foodies when they are travelling. Preparers of food and beverages and tourism retailers should supply food that represents local cultural characteristics and design relevant local food souvenirs with the appropriate packaging.Social implicationsCommunities need to realise that not all visitors are alike and that some have a deeper interest in local foods and their historical and cultural roots.Originality/valueAlthough numerous studies on the behaviours of Chinese tourists have been conducted, the research on their food consumption characteristics is limited. To date, no empirical studies have examined the relationships among foodies, food consumption motivations, food experiential values, emotions and well-being of mainland Chinese tourists, which is a knowledge gap in understanding this important market segment.

Abstract. With a ray-tracing procedure and variational data assimilation techniques, it is now possible to make direct use of radio occultation bending angles, rather than their derived temperature and moisture retrievals, in atmospheric data analysis and assimilation. This paper describes results obtained from including more than 800 GPS/MET bending angle profiles, available over an l 1-day period, 20-30 June 1995, into the National Centers for Environmental Prediction spectral statistical interpolation analyses. The methodology for assimilating the bending angles (including an impact parameter offset correction) is briefly summarized. Verified with 56 collocated radiosonde profiles, the assimilation of only GPS/MET bending angles improves the temperature and specific humidity analysis above 850 mbar. Even though the number of GPS/MET soundings is still far less than conventional data and operational satellite soundings, our results from two continuous l 1-day data assimilation cycles demonstrate a closer fit of both GPS/MET and conventional observations to the analyses between 850 and 200 hPa when the bending angles are incorporated. Including the bending angles also results in a small but consistent improvement in the short-range (6 hours) and medium-range (1-5 days) forecast skills, especially in the Southern Hemisphere. IntroductionAs shown by the Global Positioning System Meteorology (GPS/MET) experiment [Kursinski et al., 1996; Ware et al., 1996], the availability of Global Positioning System (GPS) satellites and the development of GPS receivers carried on a Low Earth Orbiting (LEO) satellite create an opportunity for active remote sounding of the Earth's atmosphere by radio occultation technology. Phase delay measurements of GPS radio signals as they are occulted by Earth's atmosphere depend on the atmospheric refractivity, which is determined by the atmospheric temperature and humidity distributions. Atmospheric profiles of bending angle and refractivity can be provided globally in all weather conditions. At temperatures below 250 K (above 5-7 km), where the effects of water vapor are negligible, vertical profiles of temperature (dry-temperature retrieval), density, and geopotential height may be obtained using the GPS limb-sounding technique. At temperatures above 250 K in the troposphere (below 5-7 km) the contribution of water vapor to the refractivity is significant, and the accuracy of the dry temperature retrieval (which assumes water vapor is negligible) is degraded [Ware et al., 1996; Kursinski et al., 1996, 1997]. It is generally impossible to compute both temperature and moisture variables from an occultation sounding using a traditional retrieval method, an underdetermined problem.

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Challenging Minisatellite Payload (CHAMP) radio occultation (RO) observations during a two-week period are assimilated into global analyses using the National Center for Environmental Prediction (NCEP) three-dimensional variational (3D-Var) system with a recently improved observation operator for assimilating GPS bending angle data. The NCEP 3D-Var system used in this research is suboptimal since Advanced Microwave Unit (AMSU) radiances are not included in our experiments. Analyses with and without CHAMP observations are compared with each other and with collocated conventional radiosonde and dropsonde data, which are excluded from both experiments. Zonal mean temperature, humidity and surface pressure differences between the GPS analyses and NO-GPS analyses are examined. The GPS analyses in the Southern Hemisphere show higher temperatures than the NO-GPS analyses, particularly in the mid-and high latitudes. The GPS analyses show drier air in the lower troposphere and more moist air in the middle troposphere compared to the NO-GPS analyses. The surface pressure is slightly increased (maximum 0.8 hPa) in the Southern Hemisphere and decreased (maximum 0.25 hPa)Corresponding author: Xiaolei Zou, Department of Meteorology, Florida State University, 404, Love Bldg, Tallahassee, Florida, 32306-4520, USA. E-mail: zou@met.fsu.edu ( 2004, Meteorological Society of Japan in the Northern Hemisphere due to the inclusion of GPS observations. Compared with the collocated independent soundings, the large cold bias (as large as 2.5 K) in the NCEP Southern Hemisphere analyses produced without CHAMP observations is significantly reduced. On average, a 20% mean error reduction in the temperature analysis is obtained in the Southern Hemisphere when CHAMP data are included. Degradations in the surface pressure analysis found from previous the GPS/Meteorology data assimilation studies are greatly reduced. The differences between the surface pressure analysis errors with and without CHAMP data are less than 0.8 G 1.5 hPa. Comparisons of numerical forecasts initialized with analyses produced with and without CHAMP occultations display a small improvement in the forecasts in the tropics and the Southern Hemisphere associated with the use of the CHAMP observations.