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Using the data of CloudSat satellite, FY series satellite, CMORPH hourly precipitation, and ERA-interim reanalysis products, this paper aims to reveal the cloud features of Tibetan Plateau Vortex (TPV) category cloud clusters over its eastward-moving regions. 107 cases of eastward-moving TPV category that occurred in the summer half-year (April to September) are picked out, and then the cloud features of them are further analyzed by statistics. The results show that the eastward-moving TPV category occurs mostly in May and June, but leastly in July and September. With consecutive enhancement of precipitation intensity and convection intensity, an increasing trend is found in the proportions of deep convection clouds and multiple layer clouds during the TPV category eastward movement. In order to reveal the inner connection among the precipitation intensity, the convection intensity, and the microphysical characteristics of TPV category cloud clusters, the TPV category cloud clusters are classified into different categories by the criteria of the precipitation intensity and the convection intensity separately. Consequently, the two different criteria share the commonality that the number concentration of both ice crystal and cloud droplets increases obviously with the enhancement of precipitation intensity or convection intensity. However, the discrepancy of conclusions also exists between the two classification criteria. A notable stretching upward trend is found in the number concentration distribution of the ice crystal and downward trend in the number concentration distribution of the cloud droplet. The same increasing trend is also discovered in the effective average radius of the ice crystal and cloud droplet. But the TPV category cloud clusters with severe convection do not present the similar variation trend both in the number concentration and the effective average radius. Hence, although the above findings confirm that the precipitation intensity, the convection intensity, and the distribution of cloud hydrometers are associated and interacting mutually, the closed function relationship among them cannot be established, and other meteorology factors related to the ambient conditions should also be taken into consideration as a complete cloud microphysical system. [ABSTRACT FROM AUTHOR]

Six C-band weather radars located in Europe (Finland, Netherlands, and Switzerland) have been used to monitor the slowly varying solar emission, which is an oscillation with an amplitude of several decibels and a period of approximately 27 days. It is caused by the fact that the number of active regions that enhance the solar radio emission with respect to the quiet component, as seen from Earth, varies because of the Sun’s rotation about its axis. The analysis is based on solar signals contained in the polar volume data produced during the operational weather scan strategy. This paper presents hundreds of daily comparisons between radar estimates and the Sun’s reference signal, during the current active Sun period (year 2014). The Sun’s reference values are accurately measured by the Dominion Radio Astrophysical Observatory (DRAO) at S-band and converted to C-band using a standard DRAO formula. Vertical and horizontal polarization receivers are able to capture the monthly oscillation of the solar microwave signal: the standard deviation of the log-transformed ratio between radars and the DRAO reference ranges from 0.26 to 0.4 dB. A larger coefficient (and a different value for the quiet Sun component) in the standard formula improves the agreement. [ABSTRACT FROM AUTHOR]

California state is among the leading producers of strawberries in the world. The value of the California strawberry crop is approximately $2.6 billion, which makes it one of the most valuable fruit crops for the state and nation’s economy. California’s weather provides ideal conditions for strawberry production and changes in weather pattern could have a significant impact on strawberry fruit production. Evaluating relationships between meteorological parameters and strawberry yield can provide valuable information and early indications of yield forecasts that growers can utilize to their advantage. Objectives of this paper were to evaluate correlations of meteorological parameters on strawberry yield for Santa Maria region and to develop meteorology based empirical yield forecasting models for strawberries. Results showed significant correlation between meteorological parameters and strawberry yield and provided a basis for yield forecasting with lead time. Results from empirical models showed that cross-validated yields were closely associated with observed yield with lead time of 2 to 5 months. Overall, this study showed great potential in developing meteorology based yield forecast using principal components. This study only looked at meteorology based yield forecasts. Skills of these models can be further improved by adding physiological parameters of strawberry to existing models for strawberry. [ABSTRACT FROM AUTHOR]

Providing a reliable, accurate, and fully informative storm surge forecast is of paramount importance for managing the hazards threatening coastal environments. Specifically, a reliable probabilistic forecast is crucial for the management of the movable barriers that are planned to become operational in 2018 for the protection of Venice and its lagoon. However, a probabilistic forecast requires multiple simulations and a considerable computational time, which makes it expensive in real-time applications. This paper describes the ensemble dressing method, a cheap operational flood prediction system that includes information about the uncertainty of the ensemble members by computing it directly from the meteorological input and the local spread distribution, without requiring multiple forecasts. Here, a sophisticated error distribution form is developed, which includes the superposition of the uncertainty caused by inaccuracies of the ensemble prediction system, which depends on surge level and lead time, and the uncertainty of the meteorological forcing, which is described using a combination of cross-basin pressure gradients. The ensemble dressing is validated over a 3-month-long period in the year 2010, during which an exceptional sequence of storm surges occurred. Results demonstrate that this computationally cheap method can provide an acceptably realistic estimate of the uncertainty. [ABSTRACT FROM AUTHOR]

This paper investigates reference evapotranspiration (ET0) changes, sensitivities to and contributions of meteorological factors in the Heihe River Basin (arid and inland region). Results show that annual ET0 over the whole basin has increasing trend (2.01 mm·10 yr−2) and there are significant increasing spatial variations from the upper (753 mm yr−1) to the lower (1553 mm yr−1) regions. Sensitivity analysis indicates that relative humidity is the most sensitive factor for seasonal and annual ET0 change, and the influence is negative. The sensitivity of minimum temperature is the weakest and negative. Contribution analysis shows that the main contributors to ET0 changes are aerodynamic factors rather than radiative factors. This study could be helpful to understand the response of ecoenvironment to the meteorological factors changes in the Heihe River Basin. [ABSTRACT FROM AUTHOR]

In this paper we present one year of meteorological and flux measurements obtained near Ny-Ålesund, Spitsbergen. Fluxes are derived by the eddy covariance method and by a hydrodynamic model approach (HMA) as well. Both methods are compared and analyzed with respect to season and mean wind direction. Concerning the wind field we find a clear distinction between 3 prevailing regimes (which have influence on the flux behavior) mainly caused by the topography at the measurement site. Concerning the fluxes we find a good agreement between the HMA and the eddy covariance method in cases of turbulent mixing in summer but deviations at stable conditions, when the HMA almost always shows negative fluxes. Part of the deviation is based on a dependence of HMA fluxes on friction velocity and the influence of the molecular boundary layer. Moreover, the flagging system of the eddy covariance software package TK3 is briefly revised. A new quality criterion for the use of fluxes obtained by the eddy covariance method, which is based on integral turbulence characteristics, is proposed. [ABSTRACT FROM AUTHOR]