Progress and Challenges in Short to Medium Range Coupled Prediction

The availability of GODAE Oceanview-type ocean forecast systems provides the opportunity to develop high-resolution, short- to medium-range coupled prediction systems. Several groups have undertaken the first experiments based on relatively unsophisticated approaches. Progress is being driven at the institutional level targeting a range of applications that represent their respective national interests with clear overlaps and opportunities for information exchange and collaboration. These include general circulation, hurricanes, extra-tropical storms, high-latitude weather and sea-ice forecasting as well as coastal air-sea interaction. In some cases, research has moved beyond case and sensitivity studies to controlled experiments to obtain statistically significant metrics

Observational needs for improving ocean and coupled reanalysis, S2S prediction, and decadal prediction

Developments in observing system technologies and ocean data assimilation (DA) are symbiotic. New observation types lead to new DA methods and new DA methods, such as coupled DA, can change the value of existing observations or indicate where new observations can have greater utility for monitoring and prediction. Practitioners of DA are encouraged to make better use of observations that are already available, for example, taking advantage of strongly coupled DA so that ocean observations can be used to improve atmospheric analyses and vice versa. Ocean reanalyses are useful for the analysis of climate as well as the initialization of operational long-range prediction models. There are many remaining challenges for ocean reanalyses due to biases and abrupt changes in the ocean-observing system throughout its history, the presence of biases and drifts in models, and the simplifying assumptions made in DA solution methods. From a governance point of view, more support is needed to bring the ocean-observing and DA communities together. For prediction applications, there is wide agreement that protocols are needed for rapid communication of ocean-observing data on numerical weather prediction (NWP) timescales. There is potential for new observation types to enhance the observing system by supporting prediction on multiple timescales, ranging from the typical timescale of NWP, covering hours to weeks, out to multiple decades. Better communication between DA and observation communities is encouraged in order to allow operational prediction centers the ability to provide guidance for the design of a sustained and adaptive observing network

An ocean reanalysis of the western Coral Sea and Great Barrier Reef

This article describes a 10 year regional ocean reanalysis of the western Coral Sea and Great Barrier Reef (GBR) from 2006-2015. Here we use the Regional Ocean Modelling System (ROMS) at 4 km resolution andEnOI (Ensemble Optimal Interpolation) data assimilation. We also account for river freshwater discharge at the coast using hydrological stream gauge observations. The system appears to constrain features of the deep ocean circulation that are important for cross-shelf exchanges such as the spatio-temporal locations of mesoscaleeddies and boundary currents. Accuracy is evaluated with forecast innovation errors respecting available observations. A four-dimensional climatological atlas of water mass properties and currents, representing 10 years of synthesis between model and data is then presented. This illustrates seasonal and climatic processes driving changes in the region, such as the El-Nino Southern Oscillation (ENSO) and its influence on sea temperature and freshwater flux to the shelf from rivers. On the shelf where dense observation coverage is limited to satellite sea surface temperature (SST), we find where SST forecast errors are low and correlations between SST and bottom temperatures are significant and take this as a reliable predictor ofbottom temperatures. Differences and correlations outside these parameters suggest areas where measurement of bottom temperature is likely to be important for a long-term and comprehensive monitoring and prediction system. The reanalysis provides a realistic physical and dynamic picture of the ocean at its given resolution that may be amenable to a variety of marine and environmental studies

Identification of the E3900 family, a second family of rye B chromosome specific repeated sequences

A second family of highly repeated sequences has been identified on the B chromosome of rye (Secale cereale). The E3900 family was detected as a variant band in EcoRI digests of +B DNA. A clone of the basic repeat of the family was obtained, and the organization of the family was investigated by genomic hybridization. The E3900 family has no apparent homology to the A chromosome sequences of rye or other members of the Gramineae. The family has been localized by in situ hybridization to the end of the long arm of the rye B chromosome. The previously characterized E1100 sequence shows in situ hybridization to the same location as the E3900 family. These results are discussed in light of current theories of the origin of B chromosomes

Applications of Satellite-Derived Ocean Measurements to Tropical Cyclone Intensity Forecasting

Sudden tropical cyclone (TC) intensification has been linked with high values of upper ocean heat content contained in mesoscale features, particularly warm ocean eddies, provided that atmospheric conditions are also favorable. Although understanding of air-sea interaction for TCs is evolving, this manuscript summarizes some of the current work being carried out to investigate the role that the upper ocean plays in TC intensification and the use of ocean parameters in forecasting TC intensity

The Marine Virtual Laboratory (version 2.1): Enabling efficient ocean model configuration

The technical steps involved in configuring a regional ocean model are analogous for all community models. All require the generation of a model grid, preparation and interpolation of topography, initial conditions, and forcing fields. Each task in configuring a regional ocean model is straightforward - but the process of downloading and reformatting data can be time-consuming. For an experienced modeller, the configuration of a new model domain can take as little as a few hours - but for an inexperienced modeller, it can take much longer. In pursuit of technical efficiency, the Australian ocean modelling community has developed the Web-based MARine Virtual Laboratory (WebMARVL). WebMARVL allows a user to quickly and easily configure an ocean general circulation or wave model through a simple interface, reducing the time to configure a regional model to a few minutes. Through WebMARVL, a user is prompted to define the basic options needed for a model configuration, including the model, run duration, spatial extent, and input data. Once all aspects of the configuration are selected, a series of data extraction, reprocessing, and repackaging services are run, and a "take-away bundle" is prepared for download. Building on the capabilities developed under Australia's Integrated Marine Observing System, WebMARVL also extracts all of the available observations for the chosen time-space domain. The user is able to download the take-away bundle and use it to run the model of his or her choice. Models supported by WebMARVL include three community ocean general circulation models and two community wave models. The model configuration from the take-away bundle is intended to be a starting point for scientific research. The user may subsequently refine the details of the model set-up to improve the model performance for the given application. In this study, WebMARVL is described along with a series of results from test cases comparing WebMARVL-configured models to observations and manually configured models. It is shown that the automatically configured model configurations produce a good starting point for scientific research

Air-sea interface and oceanic influences

International audienceCommunication about Air-sea interface and oceanic influence