ENSO suppression due to weakening of the North Atlantic thermohaline circulation

Changes of the North Atlantic thermohaline circulation (THC) excite wave patterns that readjust the thermocline globally. This paper examines the impact of a freshwater-induced THC shutdown on the depth of the Pacific thermocline and its subsequent modification of the El Niño–Southern Oscillation (ENSO) variability using an intermediate-complexity global coupled atmosphere–ocean–sea ice model and an intermediate ENSO model, respectively. It is shown by performing a numerical eigenanalysis and transient simulations that a THC shutdown in the North Atlantic goes along with reduced ENSO variability because of a deepening of the zonal mean tropical Pacific thermocline. A transient simulation also exhibits abrupt changes of ENSO behavior, depending on the rate of THC change. The global oceanic wave adjustment mechanism is shown to play a key role also on multidecadal time scales. Simulated multidecadal global sea surface temperature (SST) patterns show a large degree of similarity with previous climate reconstructions, suggesting that the observed pan-oceanic variability on these time scales is brought about by oceanic waves and by atmospheric teleconnections

Progress in paleoclimate modeling

International audienceThis paper briefly surveys areas of paleoclimate modeling notable for recent progress. New ideas, including hypotheses giving a pivotal role to sea ice, have revitalized the low-order models used to simulate the time evolution of glacial cycles through the Pleistocene, a prohibitive length of time for comprehensive general circulation models (GCMs). In a recent breakthrough, however, GCMs have succeeded in simulating the onset of glaciations. This occurs at times (most recently, 115 kyr B.P.) when high northern latitudes are cold enough to maintain a snow cover and tropical latitudes are warm, enhancing the moisture source. More generally, the improvement in models has allowed simulations of key periods such as the Last Glacial Maximum and the mid-Holocene that compare more favorably and in more detail with paleoproxy data. These models now simulate ENSO cycles, and some of them have been shown to reproduce the reduction of ENSO activity observed in the early to middle Holocene. Modeling studies have demonstrated that the reduction is a response to the altered orbital configuration at that time. An urgent challenge for paleoclimate modeling is to explain and to simulate the abrupt changes observed during glacial epochs (i.e., Dansgaard-Oescher cycles, Heinrich events, and the Younger Dryas). Efforts have begun to simulate the last millennium. Over this time the forcing due to orbital variations is less important than the radiance changes due to volcanic eruptions and variations in solar output. Simulations of these natural variations test the models relied on for future climate change projections. They provide better estimates of the internal and naturally forced variability at centennial time scales, elucidating how unusual the recent global temperature trends are

Reducing respiratory syncytial virus (RSV) hospitalization in a lower-income country by vaccinating mothers-to-be and their households

Respiratory syncytial virus is the leading cause of lower respiratory tract infection among infants. RSV is a priority for vaccine development. In this study, we investigate the potential effectiveness of a two-vaccine strategy aimed at mothers-to-be, thereby boosting maternally acquired antibodies of infants, and their household cohabitants, further cocooning infants against infection. We use a dynamic RSV transmission model which captures transmission both within households and communities, adapted to the changing demographics and RSV seasonality of a low-income country. Model parameters were inferred from past RSV hospitalisations, and forecasts made over a 10-year horizon. We find that a 50% reduction in RSV hospitalisations is possible if the maternal vaccine effectiveness can achieve 75 days of additional protection for newborns combined with a 75% coverage of their birth household co-inhabitants (∼7.5% population coverage)

Prop-Based Haptic Interaction with Co-location and Immersion: an Automotive Application

Most research on 3D user interfaces aims at providing only a single sensory modality. One challenge is to integrate several sensory modalities into a seamless system while preserving each modality's immersion and performance factors. This paper concerns manipulation tasks and proposes a visuo-haptic system integrating immersive visualization, tactile force and tactile feedback with co-location. An industrial application is presented

EX-ANTE EVALUATION OF THE ECONOMIC IMPACT OF AGRICULTURAL BIOTECHNOLOGY IN THE EUROPEAN UNION: THE CASE OF TRANSGENIC SUGARBEETS

We develop a theoretical welfare framework, which explicitly recognizes that research protected by intellectual property rights generates monopoly profits. The result is a simulation model, shaped to the European sugar sector, and enabling to assess the size and distribution of the benefits of transgenic sugarbeet adoption in the European Union and the Rest of the World.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Global welfare effects of transgenic sugar beet

Although the EU is still in a quasi moratorium stage concerning GM crops, doors for GM crops in the sugar industry seem to open. Herbicide tolerant sugar beet could mean a boost for the sugar beet sector. The ex ante impact assessment shows a created welfare of 15 billion during 1996-2014. The rule of thumb found in ex post impact studies of a sharing out between downstream and upstream sector of 2/3 versus 1/3 is seems to be applicable to this case as well. The sugar beet sector and consumers worldwide are the winners while cane growers lose due to technology eroded world prices. The reform of the EU Common market organization for sugar in 2006 seems to create an incentive for innovation to efficient European sugar producers. Crowding out of inefficient producers could take place as was one of the goals of the reform.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

An approach to valuing ponds within farming systems for aquaculture

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