The coverage and quality of remotely sensed upper-tropospheric moisture parameters have improved considerably with the deployment of a new generation of operational geostationary meteorological satellites: GOES-8/9 and GMS-5. The GOES-8/9 water vapor imaging capabilities have increased as a result of improved radiometric sensitivity and higher spatial resolution. The addition of a water vapor sensing channel on the latest GMS permits nearly global viewing of upper-tropospheric water vapor (when joined with GOES and Meteosat) and enhances the commonality of geostationary meteorological satellite observing capabilities. Upper-tropospheric motions derived from sequential water vapor imagery provided by these satellites can be objectively extracted by automated techniques. Wind fields can be deduced in both cloudy and cloud-free environments. In addition to the spatially coherent nature of these vector fields, the GOES-8/9 multispectral water vapor sensing capabilities allow for determination of wind fields over multiple tropospheric layers in cloud-free environments. This article provides an update on the latest efforts to extract water vapor motion displacements over meteorological scales ranging from subsynoptic to global. The potential applications of these data to impact operations, numerical assimilation and prediction, and research studies are discussed.

A recursive filter objective analysis method is described. It is a "successive approximation" system with the particular feature of locally varying scaling, making it especially appropriate for dealing with inhomogeneous data. Attention is given to proper treatment of lateral boundaries, which permit its use in limited domains. Thissystem provides estimates of input data quality that can be used for editing datasets before their distribution and for the weighting of data in application by other users, Two- and three-dimensional versions of the analysis operating on a Cartesian grid are used operationally at the National Environmental Satellite and Data InformationService. They are used both in the production of data and for quality control prior to dissemination. Examplesof these applications are given.

Cloud-drift winds have been produced from geostationary satellite data in the Western Hemisphere since the early 1970s. During the early years, winds were used as an aid for the short-term forecaster in an era when numerical forecasts were often of questionable quality, especially over oceanic regions. Increased computing resources over the last two decades have led to significant advances in the performance of numerical forecast models. As a result, continental forecasts now stand to gain little from the inspection or assimilation of cloud-drift wind fields. However, the oceanic data void remains, and although numerical forecasts in such areas have improved, they still suffer from a lack of in situ observations. During the same two decades, the quality of geostationary satellite data has improved considerably, and the cloud-drift wind production process has also benefited from increased computing power. As a result, fully automated wind production is now possible, yielding cloud-drift winds whose quality and quantity is sufficient to add useful information to numerical model forecasts in oceanic and coastal regions. This article will detail the automated cloud-drift wind production process, as operated by the National Environmental Satellite Data and Information Service within the National Oceanic and Atmospheric Administration.

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Dynamic software updating (DSU) systems patch programs on the fly without incurring downtime.To avoid failures due to the updating process itself, many DSU systems employ timing restrictions.However, timing restrictions are theoretically imperfect, and their practical effectiveness is an open question. This paper presents the first significant empirical evaluation of three popular timing restrictions: activeness safety (AS), which prevents updates to active functions; con-freeness safety (CFS), which only allows modifications to active functions when doing so is provably type-safe; and manual selection, which permits updates at developer chosen program points.We evaluated these timing restrictions using a series of DSU patches to three programs: OpenSSH, vsftpd, and ngIRCd. We systematically applied updates at each distinct update point reached during execution of a suite of system tests for these programs to determine which updates pass and which fail.We found that all three timing restrictions prevented most failures, but only manual selection allowed none. Further, although CFS and AS allowed many more update points, manual selection still supported updates with minimal delay. Finally, we found that manual selection required the least developer effort.Overall, we conclude that manual selection is most effective.