Abstract This study demonstrates the added benefits of assimilating Advanced Technology Microwave Sounder (ATMS) radiances in Hurricane Weather Research and Forecasting (HWRF) system to forecasts four Atlantic hurricane cases that made landfall 2012. In National Centers for Environmental Prediction (NCEP) Gridpoint Statistical Interpolation data assimilation system, HWRF model top is raised ~0.5 hPa cold start embedded changed a warm start. The ATMS quality control (QC) procedure examined...

We have used Hinode X-Ray Telescope observations and RHESSI upper limits together to characterize the differential emission measure (DEM) from a quiescent active region. find relatively smooth DEM curve with expected region peak at log T = 6.4. also high-temperature component significant ≳ 7. This is consistent previous of regions in that it does not produce observable Fe xix lines. It different generated (XRT) data alone—RHESSI rules out possibility separate approximately 7.4. The strength...

Abstract Remotely sensed soil moisture data are typically incorporated into numerical weather models under a framework of weakly coupled assimilation (WCDA), with land surface analysis scheme independent from the atmospheric component. In contrast, strongly (SCDA) allows simultaneous correction and states but has not been sufficiently explored assimilation. This study implemented variational approach to assimilate Soil Moisture Active Passive (SMAP) 9-km enhanced retrievals Noah model...

Abstract Strongly coupled land–atmosphere data assimilation has not yet been implemented into operational numerical weather prediction (NWP) systems. Up to now, upper-air measurements have assimilated mainly in atmospheric analyses, while land and near-surface surface models. Thus, this study aims explore the benefits of assimilating observations within framework strongly assimilation. Specifically, we added soil moisture as a control state ensemble Kalman filter (EnKF)-based Gridpoint...

Abstract Initialization methods are needed for geophysical components of Earth system prediction models. These from medium-range to decadal predictions and also short-range forecasts in support safety (e.g., severe weather), economic energy), other applications. Strongly coupled land–atmosphere data assimilation (SCDA), producing balanced initial conditions across the components, has not yet been introduced operational numerical weather (NWP) systems. Most NWP systems have evolved separate...

Abstract Estimates of soil moisture from two National Oceanic and Atmospheric Administration (NOAA) models are compared to in situ observations. The estimates a high-resolution atmospheric model with land surface [High-Resolution Rapid Refresh (HRRR) model] hydrologic the NOAA Climate Prediction Center (CPC). Both produce wetter soils dry regions drier wet regions, as These differences occur at most depths but larger deeper below (100 cm). Comparisons variability also assessed function...

Abstract This study characterizes the space‐time structure of soil moisture background error covariance and paves way for development a variational data assimilation system Noah land surface model coupled to Weather Research Forecasting (WRF) model. The over contiguous United States exhibits strong seasonal regional variability with largest values occurring in uppermost layer during summer. Large biases were identified, particularly southeastern States, caused mainly by discrepancy between...

Abstract The objective of this study is to develop a framework for dynamically downscaling spaceborne precipitation products using the Weather Research and Forecasting (WRF) Model with four-dimensional variational data assimilation (4D-Var). Numerical experiments have been conducted 1) understand sensitivity through point-scale 2) investigate impact seasonality associated changes in precipitation-generating mechanisms on quality spatiotemporal precipitation. experiment suggests that...

This paper presents a framework that enables simultaneous assimilation of satellite precipitation and soil moisture observations into the coupled Weather Research Forecasting (WRF) Noah land surface model through variational approaches. The authors tested by assimilating data from Tropical Rainfall Measuring Mission (TRMM) Soil Moisture Ocean Salinity (SMOS) satellite. results show both TRMM SMOS can effectively improve forecast skills precipitation, top 10-cm moisture, 2-m temperature...

Parker's model is one of the most discussed mechanisms for coronal heating and has generated much debate. We have recently obtained new scaling results in a two-dimensional (2D) version this problem suggesting that rate becomes independent resistivity statistical steady state [Ng Bhattacharjee, Astrophys. J., 675, 899 (2008)]. Our numerical work now been extended to 3D by means large-scale simulations. Random photospheric footpoint motion applied time longer than correlation obtain converged...

Abstract Hydrological applications rely on the availability and quality of precipitation products, especially model- satellite-based products for use in areas without ground measurements. It is known that complementary: model-based exhibit high during cold seasons while are better warm seasons. To explore complementary behavior this study uses 2-m air temperature as auxiliary information to evaluate high-resolution (0.1°/hourly) estimates from Weather Research Forecasting (WRF) Model version...

Abstract This study characterizes the spatial and temporal variability of background error covariance between land surface soil moisture atmospheric states for a better understanding potentials assimilating satellite data under framework strongly coupled land–atmosphere assimilation. The uses Noah model with Weather Research Forecasting (WRF) Model National Meteorological Center (NMC) method computing from 2015 to 2017 over contiguous United States. results show that forecast errors in...

Checkpointing and rollback-recovery algorithms in distributed object-based systems are presented. By utilizing the structure of objects operation invocations, authors have derived efficient that involve fewer participants than when invocations treated as messages existing for message-based used. It is planned to implement these evaluate their performance context Clouds project at Georgia Tech.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

AB Dor, Speedy Mic and Rst137B are in their early post-T Tauri evolutionary phase (<100Myr), at the age of fastest rotation life late-type stars. They straddle coronal saturation-supersaturation boundary first defined by young stars open clusters. High resolution Chandra X-ray spectra have been analysed to study properties as a function activity parameters Rossby number, $L_X/L_{bol}$ temperature index. Plasma emission measure distributions show broad peaks T~10e7K. Differences between...

We present an analysis of Chandra High Energy Transmission Grating (HETG) spectra the corona critical intermediate-activity, quadruple stellar system ξ UMa. Using maximum A/B subsystem separation in 2001, we attempted to resolve for first time X-rays two components using HETG Medium (MEG). found Aa component be at least 2 orders magnitude fainter than Bb component. used Markov Chain Monte Carlo method reconstruct differential emission measures (DEMs) and abundances discuss ionization...

Abstract Satellite and model precipitation such as the Global Precipitation Measurement (GPM) data are valuable in hydrometeorological applications. This study investigates performance of various satellite products Taiwan from 2015 to 2017, including derived Integrated Multi-satellitE Retrievals for GPM Early Final Runs (IMERG_E IMERG_F), Mapping Precipitation_near-real-time (GSMaP_NRT), Weather Research Forecasting (WRF) model. We assess these by comparing them against collected 304 surface...

A checkpointing scheme can be used to ensure forward progress of a computation (program) even when failures occur. In distributed system, many autonomous programs execute concurrently and obtain services from set shared servers. such it is desirable restrict checkpoint or rollback operation single program localize the effects failures, processes different communicate with This achieved by based on message logging consistent checkpoints system deterministic. When (communication network...

Precipitation estimates from numerical weather prediction (NWP) models are uncertain. The uncertainties can be reduced by integrating precipitation observations into NWP models. This study assimilates Version 04 Integrated Multi-satellite Retrievals for the Global Measurement (GPM) (IMERG) Final Run Weather Research and Forecasting (WRF) model data assimilation (WRFDA) system using a four-dimensional variational (4D-Var) method. Three synoptic-scale convective events over central United...

We have recently carried out a computational campaign to investigate model of coronal heating in three-dimensions using reduced magnetohydrodynamics (RMHD). Our code is built on conventional scheme the pseudo-spectral method, and parallelized MPI. The current investigation requires very long time integrations high Lundquist numbers, where formation fine layers challenge resolutions achievable even massively parallel machines. present here results port Nvidia CUDA (Compute Unified Device...