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  • 1.
    Azua-Bustos, Armando
    et al.
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain. Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.
    González-Silva, Carlos
    Facultad de Ciencias, Universidad de Tarapacá, Arica, Chile.
    Fernández-Martínez, Miguel Ángel
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Arenas-Fajardo, Cristián
    Atacama Biotech, Santiago, Chile.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Armilla, Granada, Spain.
    Fernández-Sampedro, Maite
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Fairén, Alberto G.
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain. Department of Astronomy, Cornell University, Ithaca, NY, USA.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Aeolian transport of viable microbial life across the Atacama Desert, Chile: Implications for Mars2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 11024Article in journal (Refereed)
    Abstract [en]

    Here we inspect whether microbial life may disperse using dust transported by wind in the Atacama Desert in northern Chile, a well-known Mars analog model. By setting a simple experiment across the hyperarid core of the Atacama we found that a number of viable bacteria and fungi are in fact able to traverse the driest and most UV irradiated desert on Earth unscathed using wind-transported dust, particularly in the later afternoon hours. This finding suggests that microbial life on Mars, extant or past, may have similarly benefited from aeolian transport to move across the planet and find suitable habitats to thrive and evolve.

  • 2.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Institut für Kartographie, Technische Universität Dresden.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, Maria-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martian slope streaks as plausible indicators of transient water activity2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, no 1, article id 7074Article in journal (Refereed)
    Abstract [en]

    Slope streaks have been frequently observed in the equatorial, low thermal inertia and dusty regions of Mars. The reason behind their formation remains unclear with proposed hypotheses for both dry and wet mechanisms. Here, we report an up-to-date distribution and morphometric investigation of Martian slope streaks. We find: (i) a remarkable coexistence of the slope streak distribution with the regions on Mars with high abundances of water-equivalent hydrogen, chlorine, and iron; (ii) favourable thermodynamic conditions for transient deliquescence and brine development in the slope streak regions; (iii) a significant concurrence of slope streak distribution with the regions of enhanced atmospheric water vapour concentration, thus suggestive of a present-day regolith-atmosphere water cycle; and (iv) terrain preferences and flow patterns supporting a wet mechanism for slope streaks. These results suggest a strong local regolith-atmosphere water coupling in the slope streak regions that leads to the formation of these fluidised features. Our conclusions can have profound astrobiological, habitability, environmental, and planetary protection implications

  • 3.
    Durán, Pablo
    et al.
    Norwegian University of Life Sciences, Ås, Norway.WindSim AS, Tønsberg, Norway.
    Meißner, Cathérine
    WindSim AS, Tønsberg, Norway.
    Rutledge, Kendall
    Novia University of Applied Sciences, Vasa, Finland.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Adaramola, Muyiwa S.
    Norwegian University of Life Sciences, Ås, Norway.
    Meso-microscale coupling for wind resource assessment using averaged atmospheric stability conditions2019In: Meteorologische Zeitschrift, ISSN 0941-2948, E-ISSN 1610-1227, Vol. 28, no 4, p. 273-291Article in journal (Refereed)
    Abstract [en]

    A methodology to couple Numerical Weather Prediction (NWP) models with steady-state Computational Fluid Dynamic (CFD) models for wind resource assessment applications is proposed. NWP simulations are averaged according to their atmospheric stability and wind direction. The averaged NWP simulations are used to generate the initial and boundary conditions of the CFD model. The method is applied using one year of Weather Research and Forecasting (WRF) simulations at the Honkajoki wind farm in Finland and validated by Sonic Detection and Ranging (SODAR) measurements at the site. It is shown that coupled simulations reproduce a more realistic shear for heights above 150 m. In terms of estimated energy production, there is not a big difference between coupled and standalone models. Nevertheless, a considerable difference in the horizontal wind speed patterns can be seen between the coupled and non-coupled approaches. The WRF model resolution has only a small influence on the coupled CFD results.

  • 4.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Earth Observatory of Singapore, Nanyang Technological University, Singapore.
    Koh, Tieh-Yong
    Earth Observatory of Singapore, Nanyang Technological University, Singapore; UC, Singapore University of Social Sciences, Singapore.
    Teo, Chee-Kiat
    UC, Singapore University of Social Sciences, Singapore; Centre for Climate Research Singapore, Meteorological Services Singapore, Singapore.
    Multi-scale interactions in a high-resolution tropical-belt experiment and observations2019In: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 52, no 5-6, p. 3503-3532Article in journal (Refereed)
    Abstract [en]

    The Weather Research and Forecasting (WRF) model is used to dynamically downscale 27 years of the Climate Forecast System Reanalysis (CFSR) in a tropical belt configuration at 36 km horizontal grid spacing. WRF is found to give a good rainfall climatology as observed by the Tropical Rainfall Measuring Mission (TRMM) and to reproduce well the large-scale circulation and surface radiation fluxes. The impact of conventional and Modoki-type El Niño–Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) are confirmed by linear regression. Madden–Julian Oscillation (MJO) and Boreal Summer Intra-seasonal Oscillation (BSISO) are also well-simulated. The WRF simulation shows that conventional El Niño increases (La Niña decreases) the MJO amplitude in the boreal summer while Modoki-type ENSO and IOD impacts are MJO-phase dependent. While WRF is found to perform well on seasonal to sub-seasonal timescales, it does not capture well the diurnal cycle of precipitation over the Maritime Continent. For the investigation of multi-scale interactions through the local diurnal cycle, TRMM data is used instead. In the Maritime Continent, moderate El Niño and La Niña causes anti-symmetric enhancement/reduction of the MJO’s influence on the diurnal cycle amplitudes with little change in the diurnal phase. Non-linear impacts on the diurnal amplitude with changes in diurnal phase manifest during strong ENSO. Given that the simulation does not employ data assimilation, this modified version of WRF submitted to the model developers is a suitable downscaling tool of CFSR for sub-seasonal to seasonal tropical atmospheric research.

  • 5.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada.
    Andersson, Kent
    Swedish Space Corporation, Esrange Space Center, Kiruna.
    Wind Forecasts for Rocket and Balloon Launches at the Esrange Space Center Using the WRF Model2018In: Weather and forecasting, ISSN 0882-8156, E-ISSN 1520-0434, Vol. 33, no 3, p. 813-833Article in journal (Refereed)
    Abstract [en]

    High-altitude balloons and rockets are regularly launched at the Esrange Space Center (ESC) in Kiruna, Sweden, with the aim of retrieving atmospheric data for meteorological and space studies in the Arctic region. Meteorological conditions, particularly wind direction and speed, play a critical role in the decision of whether to go ahead with or postpone a planned launch. Given the lack of high-resolution wind forecasts for this remote region, the Weather Research and Forecasting (WRF) Model is used to downscale short-term forecasts given by the Global Forecast System (GFS) for the ESC for six 5-day periods in the warm, cold, and transition seasons. Three planetary boundary layer (PBL) schemes are considered: the local Mellor-Yamada-Janjic' (MYJ), the nonlocal Yonsei University (YSU), and the hybrid local-nonlocal Asymmetric Convective Model 2 (ACM2). The ACM2 scheme is found to provide the most skillful forecasts. An analysis of the WRF Model output against the launch criteria for two of the most commonly launched vehicles, the sounding rockets Veículo de Sondagem Booster-30 (VSB-30) and Improved Orion, reveals probability of detection (POD) values that always exceeds 60% with the false alarm rate (FAR) generally below 50%. It is concluded that the WRF Model, in its present configuration, can be used to generate useful 5-day wind forecasts for the launches of these two rockets. The conclusions reached here are applicable to similar sites in the Arctic and Antarctic regions.

  • 6.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martín-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), 18100 Granada, Spain.
    High-Resolution Dynamical Downscaling of Re-Analysis Data over the Kerguelen Islands using the WRF Model2019In: Journal of Theoretical and Applied Climatology, ISSN 0177-798X, E-ISSN 1434-4483, Vol. 135, no 3-4, p. 1259-1277Article in journal (Refereed)
    Abstract [en]

    We have used the Weather Research and Forecasting (WRF) model to simulate the climate of the Kerguelen Islands (49° S, 69° E) and investigate its inter-annual variability. Here, we have dynamically downscaled 30 years of the Climate Forecast System Reanalysis (CFSR) over these islands at 3-km horizontal resolution. The model output is found to agree well with the station and radiosonde data at the Port-aux-Français station, the only location in the islands for which observational data is available. An analysis of the seasonal mean WRF data showed a general increase in precipitation and decrease in temperature with elevation. The largest seasonal rainfall amounts occur at the highest elevations of the Cook Ice Cap in winter where the summer mean temperature is around 0 °C. Five modes of variability are considered: conventional and Modoki El Niño-Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), Subtropical IOD (SIOD) and Southern Annular Mode (SAM). It is concluded that a key mechanism by which these modes impact the local climate is through interaction with the diurnal cycle in particular in the summer season when it has a larger magnitude. One of the most affected regions is the area just to the east of the Cook Ice Cap extending into the lower elevations between the Gallieni and Courbet Peninsulas. The WRF simulation shows that despite the small annual variability, the atmospheric flow in the Kerguelen Islands is rather complex which may also be the case for the other islands located in the Southern Hemisphere at similar latitudes.

  • 7.
    Fonseca, Ricardo Morais
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    MARSWRF Prediction of Entry Descent Landing Profiles: Applications to Mars Exploration2019In: Earth and Space Science, E-ISSN 2333-5084, Vol. 6, no 8, p. 1440-1459Article in journal (Refereed)
    Abstract [en]

    In this paper we use the Mars implementation of the Planet Weather Research and Forecasting model, MarsWRF, to simulate the Entry, Descent and Landing (EDL) vertical profiles from six past missions: Pathfinder, Mars Exploration Rovers Opportunity and SpiritPhoenix, Mars Science Laboratory Curiosity rover and ExoMars 2016 (Schiaparelli), and compare the results with observed data. In order to investigate the sensitivity of the model predictions to the atmospheric dust distribution, MarsWRF is run with two prescribed dust scenarios. It is concluded that the MarsWRF EDL predictions can be used for guidance into the design and planning stage of future missions to the planet, as it generally captures the observed EDL profiles, although it has a tendency to underestimate the temperature and overestimate the density for heights above 15 km. This could be attributed to an incorrect representation of the observed dust loading. We have used the model to predict the EDL conditions that may be encountered by two future missions: ExoMars 2020 and Mars 2020. When run for Oxia Planum and Jezero Crater for the expected landing time, MarsWRF predicts a large sensitivity to the dust loading in particular for the horizontal wind speed above 10‐15 km with maximum differences of up to ±30 m s‐1 for the former and ±15 m s‐1 for the latter site. For both sites, the best time for EDL, i.e. when the wind speed is generally the weakest with smaller shifts in direction, is predicted to be in the late morning and early afternoon.

  • 8.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Azu-Bustos, Armando
    Centro de Astrobiología (INTA-CSIC), Madrid, Spain. Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.
    González-Silva, Carlos
    Facultad de Ciencias, Universidad de Tarapacá, Iquique, Chile.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Granada, Spain.
    A surface temperature and moisture intercomparison study of the Weather Research and Forecasting model, in‐situ measurements and satellite observations over the Atacama Desert2019In: Quarterly Journal of the Royal Meteorological Society, ISSN 0035-9009, E-ISSN 1477-870X, Vol. 145, no 722, p. 2202-2220Article in journal (Refereed)
    Abstract [en]

    Good knowledge of the environmental conditions of deserts on Earth is relevant forclimate studies. The Atacama Desert is of particular interest as it is considered tobe the driest region on Earth. We have performed simulations using the WeatherResearch and Forecasting (WRF) model over the Atacama Desert for two week-longperiods in the austral winter season coincident with surface temperature and relativehumidity in-situ observations at three sites. We found that the WRF model generallyoverestimates the daytime surface temperature, with biases of up to 11◦C, despitegiving a good simulation of the relative humidity. In order to improve the agree-ment with observed measurements, we conducted sensitivity experiments in whichthe surface albedo, soil moisture content and five tuneable parameters in the NoahLand Surface Model (namely soil porosity, soil suction, saturated soil hydraulic con-ductivity, thebparameter used in hydraulic functions and the quartz fraction) areperturbed. We concluded that an accurate simulation is not possible, most likelybecause the Noah Land Surface Model does not have a groundwater table that maybe shallow in desert regions. The WRF-predicted land surface temperature is alsoevaluated against that estimated from the Moderate Resolution Imaging Spectrora-diometer (MODIS) instrument. While at night the satellite-derived and ground-basedmeasurements are generally in agreement, during the day MODIS estimates aretypically lower by as much as 17◦C. This is attributed to the large uncertainty inthe MODIS-estimated land surface temperatures in arid and semi-arid regions. Thefindings of this work highlight the need for ground-based observational networksin remote regions such as the Atacama Desert where satellite-derived and modelproducts may not be very accurate.

  • 9.
    Fonseca, Ricardo
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC).
    Martín-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Planetary Boundary Layer and Circulation Dynamics at Gale Crater, Mars2018In: Icarus (New York, N.Y. 1962), ISSN 0019-1035, E-ISSN 1090-2643, Vol. 302, p. 537-559Article in journal (Refereed)
    Abstract [en]

    The Mars implementation of the Planet Weather Research and Forecasting (PlanetWRF) model, MarsWRF, is used here to simulate the atmospheric conditions at Gale Crater for different seasons during a period coincident with the Curiosity rover operations. The model is first evaluated with the existing single-point observations from the Rover Environmental Monitoring Station (REMS), and is then used to provide a larger scale interpretation of these unique measurements as well as to give complementary information where there are gaps in the measurements.

    The variability of the planetary boundary layer depth may be a driver of the changes in the local dust and trace gas content within the crater. Our results show that the average time when the PBL height is deeper than the crater rim increases and decreases with the same rate and pattern as Curiosity's observations of the line-of-sight of dust within the crater and that the season when maximal (minimal) mixing is produced is Ls 225°-315° (Ls 90°-110°). Thus the diurnal and seasonal variability of the PBL depth seems to be the driver of the changes in the local dust content within the crater. A comparison with the available methane measurements suggests that changes in the PBL depth may also be one of the factors that accounts for the observed variability, with the model results pointing towards a local source to the north of the MSL site.

    The interaction between regional and local flows at Gale crater is also investigated assuming that the meridional wind, the dynamically important component of the horizontal wind at Gale, anomalies with respect to the daily mean can be approximated by a sinusoidal function as they typically oscillate between positive (south to north) and negative (north to south) values that correspond to upslope/downslope or downslope/upslope regimes along the crater rim and Mount Sharp slopes and the dichotomy boundary. The smallest magnitudes are found in the northern crater floor in a region that comprises Bradbury Landing, in particular at Ls 90° when they are less than 1 m s−1, indicating very little lateral mixing with outside air. The largest amplitudes occur in the south-western portions of the crater where they can exceed 20 m s−1. Should the slope flows along the crater rims interact with the dichotomy boundary flow, which is more likely at Ls 270° and very unlikely at Ls 90°, they are likely to interact constructively for a few hours from late evening to nighttime (∼17-23 LMST) and from pre-dawn early morning (∼5-11 LMST) hours at the norther crater rim and destructively at night (∼22-23 LMST) and in the morning (∼10-11 LMST) at the southern crater rim.

    We conclude that a better understanding of the PBL and circulation dynamics has important implications for the variability of the concentration of dust, non-condensable and trace gases at the bottom of other craters on Mars as mixing with outside air can be achieved vertically, through changes in the PBL depth, and laterally, by the transport of air into and out of the crater.

  • 10.
    Hoskins, Brian
    et al.
    Department of Meteorology, University of Reading, Reading, UK Grantham Institute—Climate Change and the environment, Imperial College, London, U.
    Yang, G.Y
    Department of Meteorology, University of Reading, Reading, UK. Climate Directorate, National Centre for Atmospheric Science, University of Reading, Reading, UK.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates.
    The detailed dynamics of the June–August Hadley Cell2020In: Quarterly Journal of the Royal Meteorological Society, E-ISSN 1477-870X, Vol. 146, no 727, p. 557-575Article in journal (Refereed)
    Abstract [en]

    The seminal theory for the Hadley Cells has demonstrated that their existence is necessary for the reduction of tropical temperature gradients to a value such that the implied zonal winds are realisable. At the heart of the theory is the notion of angular momentum conservation in the upper branch of the Hadley Cells. Eddy mixing associated with extra‐tropical systems is invoked to give continuity at the edge of the Hadley Cell and to reduce the subtropical jet by a factor of 3 or more to those observed. In this paper a detailed view is presented of the dynamics of the June–August Hadley Cell, as given by ERA data for the period 1981–2010, with an emphasis on the dynamics of the upper branch. The steady and transient northward fluxes of angular momentum have a very similar structure, both having a maximum on the equator and a reversal in sign near 12°S, with the transient flux merging into that associated with eddies on the winter sub‐tropical jet. In the northward absolute vorticity flux, the Coriolis torque is balanced by both the steady and transient fluxes. The overturning circulations that average to give the Hadley Cell are confined to specific longitudinal regions, as are the steady and transient momentum fluxes. In these regions, both intra‐seasonal and synoptic variations are important. The dominant contributor to the Hadley Cell is from the Indian Ocean and W Pacific regions, and the maxima in OLR variability and meridional wind in these regions have a characteristic structure associated with the Westward‐moving Mixed Rossby‐Gravity wave. Much of the upper tropospheric motion into the winter hemisphere occurs in filaments of air from the summer equatorial region. These filaments can reach the winter sub‐tropical jet, leading to the strengthening of it and of the eddies on it, implying strong tropical‐extratropical interaction.

  • 11.
    Wang, Jianfeng
    et al.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Rutledge, Kendall
    Novia University of Applied Sciences, Vaasa, Finland.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra, Granada, Spain The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University at Misasa, Tottori, Japan.
    Yu, Jun
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    A Hybrid Statistical-Dynamical Downscaling of Air Temperature over Scandinavia Using the WRF Model2020In: Advances in Atmospheric Sciences, ISSN 0256-1530, E-ISSN 1861-9533, Vol. 37, no 1, p. 57-74Article in journal (Refereed)
    Abstract [en]

    An accurate simulation of air temperature at local scales is crucial for the vast majority of weather and climate applications. In this work, a hybrid statistical–dynamical downscaling method and a high-resolution dynamical-only downscaling method are applied to daily mean, minimum and maximum air temperatures to investigate the quality of localscale estimates produced by downscaling. These two downscaling approaches are evaluated using station observation data obtained from the Finnish Meteorological Institute over a near-coastal region of western Finland. The dynamical downscaling is performed with the Weather Research and Forecasting (WRF) model, and the statistical downscaling method implemented is the Cumulative Distribution Function-transform (CDF-t). The CDF-t is trained using 20 years of WRF-downscaled Climate Forecast System Reanalysis data over the region at a 3-km spatial resolution for the central month of each season. The performance of the two methods is assessed qualitatively, by inspection of quantile-quantile plots, and quantitatively, through the Cramer-von Mises, mean absolute error, and root-mean-square error diagnostics. The hybrid approach is found to provide significantly more skillful forecasts of the observed daily mean and maximum air temperatures than those of the dynamical-only downscaling (for all seasons). The hybrid method proves to be less computationally expensive, and also to give more skillful temperature forecasts (at least for the Finnish near-coastal region).

  • 12.
    Wang, Jianfeng
    et al.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Fonseca, Ricardo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Rutledge, Kendall
    Novia University of Applied Sciences, Vaasa, Finland.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Granada, Spain.
    Yu, Jun
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Weather Simulation Uncertainty Estimation Using Bayesian Hierarchical Models2019In: Journal of Applied Meteorology and Climatology, ISSN 1558-8424, E-ISSN 1558-8432, Vol. 58, no 3, p. 585-603Article in journal (Refereed)
    Abstract [en]

    Estimates of the uncertainty of model output fields (e.g., 2-m temperature, surface radiation fluxes, or wind speed) are of great value to the weather and climate communities. The traditional approach for the uncertainty estimation is to conduct an ensemble of simulations where the model configuration is perturbed and/or different models are considered. This procedure is very computationally expensive and may not be feasible, in particular for higher-resolution experiments. In this paper, a new method based on Bayesian hierarchical models (BHMs) that requires just one model run is proposed. It is applied to the Weather Research and Forecasting (WRF) Model’s 2-m temperature in the Botnia–Atlantica region in Scandinavia for a 10-day period in the winter and summer seasons. For both seasons, the estimated uncertainty using the BHM is found to be comparable to that obtained from an ensemble of experiments in which different planetary boundary layer (PBL) schemes are employed. While WRF-BHM is not capable of generating the full set of products obtained from an ensemble of simulations, it can be used to extract commonly used diagnostics including the uncertainty estimation that is the focus of this work. The methodology proposed here is fully general and can easily be extended to any other output variable and numerical model.

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