Displaced Ensemble variational assimilation method to incorporate microwave imager brightness temperatures into a cloud-resolving model

نویسنده

  • Kazumasa AONASHI
چکیده

We developed a data assimilation method that incorporates the microwave imager (MWI) brightness temperatures (TBs) into the cloud-resolving model (CRM) developed by the Japan Meteorological Agency (JMANHM). This method consisted of a displacement error correction scheme and an Ensemble-based variational assimilation scheme. In the displacement error correction scheme, we obtained the optimum displacement that maximized the conditional probability of TB observation given the displaced CRM variables. In the assimilation scheme, we derived a cost function in the displaced Ensemble forecast error subspace. Then, we obtained the analyses of CRM variables by non-linear minimization of the cost function. We applied this method to assimilate TMI (TRMM Microwave Imager) low-frequency TBs (10, 19, and 21 GHz with vertical polarization) for a Typhoon case around Okinawa (9 June 2004). The results of the assimilation experiments showed that the assimilation of TMI TBs alleviated the large-scale displacement errors and improved the CRM forecasts.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Direct assimilation of AMSR - E brightness temperatures for estimating sea - ice concentration

In this paper a method to directly assimilate brightness temperatures from the Advanced Microwave Scanning Radiometer (AMSR-E) to produce ice concentration analyses within a three-dimensional variational data assimilation system is investigated. To assimilate the brightness temperatures a simple radiative transfer model is used as the forward model which maps the state vector to the observation...

متن کامل

Evaluation of radiative transfer schemes for mesoscale model data assimilation: a case study

The assimilation of Special Sensor Microwave Imager (SSM/I) data into the Mesoscale Model 5 (MM5) allows for improving the weather forecast. However the results suggested an update the Radiative Transfer Equation (RTE) within the three-dimensional variational (3DVAR) algorithm which is tailored for non rainy conditions only. To this purpose, a new RTE algorithm is tested, in order to account fo...

متن کامل

A dual-pass variational data assimilation framework for estimating soil moisture profiles from AMSR-E microwave brightness temperature

[1] To overcome the difficulties in determining the optimal parameters needed for a radiative transfer model (RTM), which acts as the observational operator in a land data assimilation system, we have designed a dual-pass assimilation (DP-En4DVar) framework to optimize the model state (volumetric soil moisture content) and model parameters simultaneously using the gridded Advanced Microwave Sca...

متن کامل

Combined Radar and Radiometer Analysis of Precipitation Profiles for a Parametric Retrieval Algorithm

A methodology to analyze precipitation profiles using the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) and precipitation radar (PR) is proposed. Rainfall profiles are retrieved from PR measurements, defined as the best-fit solution selected from precalculated profiles by cloud-resolving models (CRMs), under explicitly defined assumptions of drop size distribution (DSD) and ...

متن کامل

Use of the Ocean Surface Wind Direction Signal in Microwave Radiance Assimilation

We developed an empirical relative wind direction (RWD) model function to represent azimuthal variations of oceanic microwave brightness temperatures of vertical and horizontal polarizations. The RWD model function was based on brightness temperature measurements from the Advanced Microwave Scanning Radiometer and Special Sensor Microwave Imager Sounder (SSMIS). Ocean surface wind vector data f...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2010