Aufbereitung meteorologischer Daten zur Unterstützung einer globalen agrarmeteorologischen Beratung

<p>Im Rahmen einer agrarmeteorologischen Beratung ist die Berechnung der Verdunstung für spezifische Agrarkulturen mit geeigneten Modellen möglichst auf einer stündlichen Zeitskala erforderlich. Im DWD ist hierzu das Modell AMBAV (Agrarmeteorologisches Modell zur Berechnung der aktuellen Verdunstung) entwickelt worden und wird für die nationale agrarmeteorologische Beratung operationell mit Vorhersagedaten und für Wirkanalysen auch mit Klimadaten verwendet. Insbesondere hinsichtlich globaler Anwendungen liegen gemessene oder mit Klimamodellen berechnete meteorologische Datenzeitreihen häufig nur für eine tägliche Zeitskala, oder als Modelldaten für ausgewählte Elemente bestenfalls in einer 6-stündigen Zeitskala, vor. Dies sind Tagesmittel oder Tagessummen (z.B. Wind bzw. Globalstrahlung und Niederschlag) sowie gegebenenfalls tägliche Extremwerte (Minimum und Maximum der Lufttemperatur, stärkste Tagesböe).</p> <p>Zur Bereitstellung stündlicher Daten aus Tagesdaten wurde daher ein Präprozessor entwickelt, der gemessene Stationsdaten (Modus „Station“) oder modellierte Daten globaler Modelle (Modus „Gitter“) verwendet. Dabei wurde vorausgesetzt, dass im Vorfeld einer Erarbeitung von zeitlichen Disaggregierungsverfahren keine umfangreichen Klimaanalysen durchgeführt werden müssen sondern weitestgehend auf Erfahrung zurückgegriffen werden kann. Vorhandene Programme (z.B. MELODIST) konnten jedoch wegen teilweise anderer Zielstellung oder Datenanforderungen nicht ohne weiteres verwendet werden. So wurde z.B. für die Tagessumme der Globalstrahlung auf das Angström-Verfahren (FAO, 1998), für den Niederschlag auf das Kaskadenverfahren nach Olsson (1998), für die Lufttemperatur auf den „sin-exp-Ansatz“ nach Parton und Logan (1981) und für den Wind auf die „normierte Böen­geschwindigkeit“ (Verkaik, 2000) zurückgegriffen. Für erforderliche Interpolationen werden das Newton-Verfahren und das „cubic hermite spline“ verwendet.</p> <p>Die vorgestellten Verfahren werden mit Stationsdaten des ZAMF und beispielhaft mit Modelldaten des GFCS für Madagaskar angewendet.</p> <p><strong>Literatur</strong></p> <p>FAO (Food and Agriculture Organization), 1998: Crop evaporation – Guidelines for computing crop water requirements. Irrigation and Drainage Paper 56, 300 p.</p> <p>Olsson, J., 1998: Evaluation of a scaling cascade model for temporal rainfall disaggregation. Hydrology and Earth System Sciences, 2, p.19-30.</p> <p>Parton, W.J. and J.A. Logan, 1981: A model for diurnal variation in soil and air temperature. Agricultural Meteorology, 23, p.205-216.</p> <p>Verkaik, J.W., 2000: Evaluation of two gustiness models for exposure correction calculations. Journal of Applied Meteorology, 39, p.1613-1626.</p>

Characterizing large-scale circulation triggering heavy precipitation amounts over the northern French Alps

<p><span>Large-scale circulations (LSCs) explain a significant part of Alpine precipitations. Characterizing circulations triggering heavy precipitation is usually done using weather-type classifications. A different characterization is implemented here, based on analogy using the atmospheric descriptors proposed in Blanchet et al 2018, 2019. These descriptors are both related to the dynamics of LSC and to their relative position in the atmospheric space. </span><span>This work is applied to the Isère river catchment for the 1950-2011 period, considering a 3-</span><span>day time step. The 500 hPa and 1000 hPa geopotential heights covering part of the western Europe are used separately to represent LSC. Two analogy criteria are investigated for constructing the atmospheric descriptors, namely TWS and RMSE.</span></p><p>Our results reveal that LSCs triggering heavy precipitation amounts correspond to strong geostrophic wind with quasi constant direction during the three days, corresponding to blocking situations in altitude. Moreover, those patterns of circulation are among the least singulars, and they show the highest degree of clustering in the atmospheric space. We interpret the latest results by the fact that heavy precipitation LSCs feature twin circulation patterns. In addition, the 500 hPa geopotential height appears to discriminate better heavy precipitation situations than the 1000 hPa one. Finally, our work points out the benefit of a combined use of TWS and RMSE. TWS gives information about the direction of geostrophic wind, while RMSE -combined with TWS- informs about its strength.</p><p>References:</p><p>Blanchet, J., Stalla, S., and Creutin, J.-D. (2018). Analogy of multi-day sequences of atmospheric circulation favoring large rainfall accumulation over the French Alps. Atmospheric Science Letters.</p><p>Blanchet, J., Creutin, J-D. <span>(2019). Modelling rainfall accumulations over several days in the French Alps using low-dimensional atmospheric predictors based on analogy. Journal of Applied Meteorology and Climatology.</span></p>

100 Years of Progress in Applied Meteorology. Part III: Additional Applications

Applied meteorology is an important and rapidly growing field. This chapter concludes the three-chapter series of this monograph describing how meteorological information can be used to serve society’s needs while at the same time advancing our understanding of the basics of the science. This chapter continues along the lines of Part II of this series by discussing ways that meteorological and climate information can help to improve the output of the agriculture and food-security sector. It also discusses how agriculture alters climate and its long-term implications. It finally pulls together several of the applications discussed by treating the food–energy–water nexus. The remaining topics of this chapter are those that are advancing rapidly with more opportunities for observation and needs for prediction. The study of space weather is advancing our understanding of how the barrage of particles from other planetary bodies in the solar system impacts Earth’s atmosphere. Our ability to predict wildland fires by coupling atmospheric and fire-behavior models is beginning to impact decision-support systems for firefighters. Last, we examine how artificial intelligence is changing the way we predict, emulate, and optimize our meteorological variables and its potential to amplify our capabilities. Many of these advances are directly due to the rapid increase in observational data and computer power. The applications reviewed in this series of chapters are not comprehensive, but they will whet the reader’s appetite for learning more about how meteorology can make a concrete impact on the world’s population by enhancing access to resources, preserving the environment, and feeding back into a better understanding how the pieces of the environmental system interact.

100 Years of Progress in Applied Meteorology. Part II: Applications that Address Growing Populations

The human population on Earth has increased by a factor of 4.6 in the last 100 years and has become more centered in urban environments. This expansion and migration pattern has resulted in stresses on the environment. Meteorological applications have helped to understand and mitigate those stresses. This chapter describes several applications that enable the population to interact with the environment in more sustainable ways. The first topic treated is urbanization itself and the types of stresses exerted by population growth and its attendant growth in urban landscapes—buildings and pavement—and how they modify airflow and create a local climate. We describe environmental impacts of these changes and implications for the future. The growing population uses increasing amounts of energy. Traditional sources of energy have taxed the environment, but the increase in renewable energy has used the atmosphere and hydrosphere as its fuel. Utilizing these variable renewable resources requires meteorological information to operate electric systems efficiently and economically while providing reliable power and minimizing environmental impacts. The growing human population also pollutes the environment. Thus, understanding and modeling the transport and dispersion of atmospheric contaminants are important steps toward regulating the pollution and mitigating impacts. This chapter describes how weather information can help to make surface transportation more safe and efficient. It is explained how these applications naturally require transdisciplinary collaboration to address these challenges caused by the expanding population.

Comparison of TRMM Derived Rainfall Products for Extreme Rains over Maritime Continent

Sekaranom AB, Masunaga H. Comparison of TRMM-Derived Rainfall Products for General and Extreme Rains over the Maritime Continent. Journal of Applied Meteorology and Climatology. 2017 Jul;56(7):1867-81. https://doi.org/10.1175/JAMC-D-16-0272.1

100 Years of Progress in Applied Meteorology. Part I: Basic Applications

The field of atmospheric science has been enhanced by its long-standing collaboration with entities with specific needs. This chapter and the two subsequent ones describe how applications have worked to advance the science at the same time that the science has served the needs of society. This chapter briefly reviews the synergy between the applications and advancing the science. It specifically describes progress in weather modification, aviation weather, and applications for security. Each of these applications has resulted in enhanced understanding of the physics and dynamics of the atmosphere, new and improved observing equipment, better models, and a push for greater computing power.