Here, we investigated the impact of assimilating satellite-based product Global Positioning System (GPS) radio occultation (RO) refractivity profiles data on simulation selected extreme rainfall events in three states southern India: Tamil Nadu, Telangana, and Kerala. We assimilated GPS RO into weather research forecasting model using a 3DVar assimilation technique evaluated results against una...

40 The ARPS 3DVAR system is enhanced to include the analysis of radar-derived 41 refractivity measurements. These refractivity data are most sensitive to atmospheric moisture 42 content and provide high-resolution information on near-surface moisture that is important to 43 convective initiation (CI) and precipitation forecasting. Observing system simulation 44 experiments (OSSEs) are performed...

This paper investigates the impacts of assimilating measurements of different state variables, which can be potentially available from various observational platforms, on the cycled analysis and short-range forecast of supercell thunderstorms by performing a set of observing system simulation experiments (OSSEs) using a storm-scale three-dimensional variational data assimilation (3DVAR) method....

[1] In this paper, electron densities during 25–28 September 2000 observed by the Millstone Hill incoherent scatter radar (ISR) are assimilated into a one-dimensional midlatitude ionospheric theoretical model by using an ensemble Kalman filter (EnKF) technique. It is found that (1) the derived vertical correlation coefficients of electron density show obvious altitude dependence. These variatio...

The present paper aims to provide a brief review on several deterministic ensemble Kalman filtering (EnKF) methods and the related practical techniques to prevent filter divergence. Since Evensen (1994), several formulations of EnKF have been proposed, and Whitaker and Hamill (2002) suggested that a deterministic method, a.k.a. an ensemble square root filter (EnSRF, Andrews 1968), is expected t...

The impact of assimilating Argo data into an initial field on the short-term forecasting accuracy of temperature and salinity is quantitatively estimated by using a forecasting system of the western North Pacific, on the base of the Princeton ocean model with a generalized coordinate system (POMgcs). This system uses a sequential multigrid three-dimensional variational (3DVAR) analysis scheme t...

Abstract In this work we show how it is possible to derive a new set of nudging equations, tool still used in many data assimilation problems, starting from statistical physics considerations and availing ourselves stochastic parameterizations that take into account unresolved interactions. The fluctuations are thought as Gaussian white noise with zero mean. derivation based on the conditioned ...

Mechanisms controlling the heat budget of North Sea are investigated based on a combination satellite sea surface temperature measurements and numerical model simulations. Lateral fluxes across shelf edge into Baltic as well vertical ocean-atmosphere exchange considered. A 3-D variational (3DVAR) data assimilation (DA) scheme is applied, which contains assumed error correlations that depend mix...