Variability of the winter wind waves and swell in the North Atlantic and North Pacific as revealed by the Voluntary Observing Ship data

This paper analyses secular changes and interannual variability in the wind wave, swell, and significant wave height (SWH) characteristics over the North Atlantic and North Pacific on the basis of wind wave climatology derived from the visual wave observations of voluntary observing ship (VOS) officers. These data are available from the International Comprehensive Ocean–Atmosphere Data Set (ICOADS) collection of surface meteorological observations for 1958–2002, but require much more complicated preprocessing than standard meteorological variables such as sea level pressure, temperature, and wind. Visual VOS data allow for separate analysis of changes in wind sea and swell, as well as in significant wave height, which has been derived from wind sea and swell estimates. In both North Atlantic and North Pacific midlatitudes winter significant wave height shows a secular increase from 10 to 40 cm decade−1 during the last 45 yr. However, in the North Atlantic the patterns of trend changes for wind sea and swell are quite different from each other, showing opposite signs of changes in the northeast Atlantic. Trend patterns of wind sea, swell, and SWH in the North Pacific are more consistent with each other. Qualitatively the same conclusions hold for the analysis of interannual variability whose leading modes demonstrate noticeable differences for wind sea and swell. Statistical analysis shows that variability in wind sea is closely associated with the local wind speed, while swell changes can be driven by the variations in the cyclone counts, implying the importance of forcing frequency for the resulting changes in significant wave height. This mechanism of differences in variability patterns of wind sea and swell is likely more realistic than the northeastward propagation of swells from the regions from which the wind sea signal originates

Advancing High-Speed Rail Policy in the United States, Research Report 11-18

This report builds on a review of international experience with high-speed rail projects to develop recommendations for a High-speed rail policy framework for the United States. The international review looked at the experience of Korea, Taiwan, China, and several countries in Europe. Countries in Asia and Europe have pursued high-speed rail (HSR) to achieve various goals, which include relieving congestion on highway networks, freeing up capacity on rail network for freight train operations, and reducing travel time for travelers. Some of the key rationales do not work well in the US context. As an example, in the US, freight companies own most of the rail network and, hence, do not need government intervention to free up capacity for their operations. We concluded the potential to reduce travel times coupled with improved travel time reliability and safety will be the strongest selling points for HSR in the US. HSR lines work best in high-density, economically active corridors. Given that there are a limited number of such corridors in the US, our study recommends the US HSR project funding mix be skewed heavily toward state bonds guaranteed by the federal government. This will ensure that the states that benefit directly from the projects pay most of the costs, making it more palatable to states that may not have HSR projects. For the projects that span multiple states, member states may have to negotiate the level of financial responsibility they will bear, and this will require detailed negotiations and financial setups that are not addressed in this report. Other measures the federal government needs to put in place include designating a key agency and dedicated funding source, and developing regulations and specifications for HSR design and construction. States that embark on HSR projects should start with formal legislation and put in place structures to ensure sustained political support throughout the planning and construction of the project. The federal government also needs to move quickly to foster educational and training centers to build up the HSR workforce in the country

Recent blackouts in US and continental Europe: is liberalisation to blame?

The paper starts with a detailed technical overview of recent blackouts in the US, Sweden/Denmark and Italy in order to analyse common threads and lessons to be learnt. The blackouts have exposed a number of challenges facing utilities worldwide. Increased liberalisation of electricity supply industry has resulted in a significant increase in inter-area (or cross-border) trades which often are not properly accounted for when assessing system security. The traditional decentralised way of operating systems by TSOs, with each TSO looking after its own control area and little information exchange, resulted in inadequate and slow response to contingencies. A new mode of coordinated operation for real-time security assessment and control is needed in order to maintain system security. This new mode of operation requires overcoming a number of organisational, psychological, legal and technical challenges but the alternative is either to risk another blackout or run the interconnected system very conservatively, maintaining large security margin at a high cost to everyone. The paper also includes technical appendices explaining engineering power system concepts to non-engineering audience

New England Overview: A Guide to Large-Scale Energy Infrastructure Issues in 2015

The report outlines how regional electricity and natural gas infrastructure decisions are made. It examines the current proposals to expand electricity transmission lines and natural gas pipelines into New England, as solutions to electricity and gas price and reliability issues, and briefly discusses the major implications of both

Regional assessment of groundwater recharge in the lower Mekong Basin

Groundwater recharge remains almost totally unknown across the Mekong River Basin, hindering the evaluation of groundwater potential for irrigation. A regional regression model was developed to map groundwater recharge across the Lower Mekong Basin where agricultural water demand is increasing, especially during the dry season. The model was calibrated with baseflow computed with the local-minimum flow separation method applied to streamflow recorded in 65 unregulated sub-catchments since 1951. Our results, in agreement with previous local studies, indicate that spatial variations in groundwater recharge are predominantly controlled by the climate (rainfall and evapotranspiration) while aquifer characteristics seem to play a secondary role at this regional scale. While this analysis suggests large scope for expanding agricultural groundwater use, the map derived from this study provides a simple way to assess the limits of groundwater-fed irrigation development. Further data measurements to capture local variations in hydrogeology will be required to refine the evaluation of recharge rates to support practical implementations

Recent blackouts in US and continental Europe: is liberalisation to blame?

The paper starts with a detailed technical overview of recent blackouts in the US, Sweden/Denmark and Italy in order to analyse common threads and lessons to be learnt. The blackouts have exposed a number of challenges facing utilities worldwide. Increased liberalisation of electricity supply industry has resulted in a significant increase in inter-area (or cross-border) trades which often are not properly accounted for when assessing system security. The traditional decentralised way of operating systems by TSOs, with each TSO looking after its own control area and little information exchange, resulted in inadequate and slow response to contingencies. A new mode of coordinated operation for real-time security assessment and control is needed in order to maintain system security. This new mode of operation requires overcoming a number of organisational, psychological, legal and technical challenges but the alternative is either to risk another blackout or run the interconnected system very conservatively, maintaining large security margin at a high cost to everyone. The paper also includes technical appendices explaining engineering power system concepts to non-engineering audience.electricity, USA, Sweden, Denmark

Investing in Mobility: Freight Transport in the Hudson Region

Proposes a framework for assessing alternative investments in freight rail, highway, and transit capacity that would increase the ability to improve mobility and air quality in the New York metropolitan area

Civil tiltrotor missions and applications. Phase 2: The commercial passenger market

The commercial passenger market for the civil tiltrotor was examined in phase 2. A market responsive commercial tiltrotor was found to be technically feasible, and a significant worldwide market potential was found to exist for such an aircraft, especially for relieving congestion in urban area-to-urban area service and for providing cost effective hub airport feeder service. Potential technical obstacles of community noise, vertiport area navigation, surveillance, and control, and the pilot/aircraft interface were determined to be surmountable. Nontechnical obstacles relating to national commitment and leadership and development of ground and air infrastructure were determined to be more difficult to resolve; an innovative public/private partnership is suggested to allow coordinated development of an initial commercial tiltrotor network to relieve congestion in the crowded US Northeast corridor by the year 2000

Policies and Measures to Mitigate Potential Environmental Impacts of Cross Border Infrastructure Projects in Asia

While bringing positive impacts and benefits, cross-border infrastructure projects face additional challenges relative to national projects. Moreover, such projects involve a variety of technical, regulatory, institutional, and legal factors, and their obstacles constrain the development of cross-border infrastructure projects. This paper argues that proper technical specifications and well-functioning regulatory, institutional and legislative/legal frameworks with clearer lines of oversight are crucial to getting such projects off the ground in the first place and to ensure that they operate properly and reliably while minimizing their environmental impacts. It is pointed out that many issues in theses areas need to be addressed at the national level. The paper concludes that such domestic efforts, coupled with regional frameworks and arrangements wherever necessary, will promote the further development of cross-border infrastructure projects.asia cross-border infrastructure; environmental impact; asia regional integration