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In Defense of Snow Days

March 27, 2015 Comments off

In Defense of Snow Days
Source: Education Next

This study provides a fresh look at the impact of instructional time lost due to weather-related student absences, as well as to school closings. Using student-level data from Massachusetts, I find that each one-day increase in the student absence rate driven by bad weather reduces math achievement by up to 5 percent of a standard deviation, suggesting that differences in average student attendance may account for as much as one-quarter of the income-based achievement gap in the state. Conversely, instructional time lost to weather-related school closings has no impact on student test scores.

What could explain these apparently conflicting results? It appears that teachers and schools are well prepared to deal with coordinated disruptions of instructional time like snow days but not with absences of different students at different times. In short, individual absences and not school closings are responsible for the achievement impacts of bad weather.

The UN World Water Development Report 2015, Water for a Sustainable World

March 27, 2015 Comments off

The UN World Water Development Report 2015, Water for a Sustainable World
Source: United Nations

The 2015 edition of the United Nations World Water Development Report (WWDR 2015), titled Water for a Sustainable World, will be launched at the official celebration of the World Water Day, on March 20.

The WWDR 2015 demonstrates how water resources and services are essential to achieving global sustainability. Taking account of economic growth, social equity and environmental sustainability, the report’s forward-looking narrative describes how major challenges and change factors in the modern world will affect – and can be affected by – water resources, services and related benefits. The report provides a comprehensive overview of major and emerging trends from around the world, with examples of how some of the trend‐related challenges have been addressed, their implications for policy‐makers, and further actions that can be taken by stakeholders and the international community.

Mitigating Reptile Road Mortality: Fence Failures Compromise Ecopassage Effectiveness

March 27, 2015 Comments off

Mitigating Reptile Road Mortality: Fence Failures Compromise Ecopassage Effectiveness
Source: PLoS ONE

Roadways pose serious threats to animal populations. The installation of roadway mitigation measures is becoming increasingly common, yet studies that rigorously evaluate the effectiveness of these conservation tools remain rare. A highway expansion project in Ontario, Canada included exclusion fencing and ecopassages as mitigation measures designed to offset detrimental effects to one of the most imperial groups of vertebrates, reptiles. Taking a multispecies approach, we used a Before-After-Control-Impact study design to compare reptile abundance on the highway before and after mitigation at an Impact site and a Control site from 1 May to 31 August in 2012 and 2013. During this time, radio telemetry, wildlife cameras, and an automated PIT-tag reading system were used to monitor reptile movements and use of ecopassages. Additionally, a willingness to utilize experiment was conducted to quantify turtle behavioral responses to ecopassages. We found no difference in abundance of turtles on the road between the un-mitigated and mitigated highways, and an increase in the percentage of both snakes and turtles detected dead on the road post-mitigation, suggesting that the fencing was not effective. Although ecopassages were used by reptiles, the number of crossings through ecopassages was lower than road-surface crossings. Furthermore, turtle willingness to use ecopassages was lower than that reported in previous arena studies, suggesting that effectiveness of ecopassages may be compromised when alternative crossing options are available (e.g., through holes in exclusion structures). Our rigorous evaluation of reptile roadway mitigation demonstrated that when exclusion structures fail, the effectiveness of population connectivity structures is compromised. Our project emphasizes the need to design mitigation measures with the biology and behavior of the target species in mind, to implement mitigation designs in a rigorous fashion, and quantitatively evaluate road mitigation to ensure allow for adaptive management and optimization of these increasingly important conservation tools.

See: Mitigating reptile road mortality

CRS — Federal Research and Development Funding: FY2016 (March 18, 2015)

March 25, 2015 Comments off

Federal Research and Development Funding: FY2016 (PDF)
Source: Congressional Research Service (via Federation of American Scientists)

President Obama’s budget request for FY2016 includes $145.694 billion for R&D in FY2016, an increase of $7.625 billion (5.5%) over the estimated FY2015 R&D funding level of $138.069 billion. The request represents the President’s R&D priorities; Congress may opt to agree with part or all of the request, or it may express different priorities through the appropriations process. In particular, Congress will play a central role in determining the growth rate and allocation of the federal R&D investment in a period of intense pressure on discretionary spending. Budget caps may limit overall R&D funding and may require movement of resources across disciplines, programs, or agencies to address priorities.

PJM Interconnection Economic Analysis of the EPA Clean Power Plan Proposal

March 24, 2015 Comments off

PJM Interconnection Economic Analysis of the EPA Clean Power Plan Proposal (PDF)
Source: PJM Interconnection

At the request of the Organization of PJM States, Inc., PJM Interconnection has analyzed potential economic impacts on electric power generation in the PJM footprint resulting from the U.S. Environmental Protection Agency’s Clean Power Plan. The plan, proposed by EPA in June 2014, seeks a 30-percent reduction in carbon dioxide emissions from the electricity sector by 2030 (compared to 2005 levels). PJM does not take positions for or against pending regulations but does provide independent expert analysis on the potential economic and reliability impacts of proposed regulatory rules and legislation.

The Organization of PJM States, which represents state utility regulators in the region served by PJM, requested analyses of several scenarios including a comparison of regional compliance versus state-by-state compliance. PJM included additional scenarios with different assumptions in the analysis to provide modeled results covering a wide range of possible outcomes. In total PJM analyzed 17 distinct scenarios – each was evaluated with and without the implementation of the Clean Power Plan. The scenarios covered varying combinations and levels of renewable resources, energy efficiency, natural gas prices, nuclear generation and new entry of natural gas combined-cycle resources.

High-level insights from the economic analysis include:

• Fossil steam unit retirements (coal, oil and gas) probably will occur gradually. As the CO2 emission limits decline over time, the financial positions of high-emitting resources should become increasingly less favorable, with lower-emitting resources displacing them more often in the competitive energy market.
• Electricity production costs are likely to increase with compliance because larger amounts of higher-cost, cleaner generation will be used to meet emissions targets.
• The price of natural gas likely will be a primary driver of the cost of reducing CO2 emissions if natural gas combined-cycle units become a significant source of replacement generation for coal and other fossil steam units.
• Adding more energy efficiency and renewable energy and retaining more nuclear generation would likely lead to lower CO2 prices; this could result in fewer megawatts of fossil steam resources at risk of retirement because lower CO2 prices may reduce the financial stress on fossil steam resources under this scenario.
• State-by-state compliance options, compared to regional compliance options, likely would result in higher compliance costs for most PJM states. This is because there are fewer low-cost options available within state boundaries than across the entire region. However, results will vary by state given differing state targets and generation mixes. PJM modeled regional versus individual state compliance only under a mass-based approach.
• State-by-state compliance options would increase the amount of capacity at risk for retirement because some states likely would face higher CO2 prices in an individual compliance approach.

See also: State-Level Detail (PDF)
See also: FAQs (PDF)

Measuring Research and Development Expenditures in the U.S. Nonprofit Sector: Conceptual and Design Issues: Summary of a Workshop (2015)

March 24, 2015 Comments off

Measuring Research and Development Expenditures in the U.S. Nonprofit Sector: Conceptual and Design Issues: Summary of a Workshop (2015)
Source: National Research Council

National Center for Science and Engineering Statistics (NCSES) of the National Science Foundation is responsible for national reporting of the research and development (R&D) activities that occur in all sectors of the United States economy. For most sectors, including the business and higher education sectors, NCSES collects data on these activities on a regular basis. However, data on R&D within the nonprofit sector have not been collected in 18 years, a time period which has seen dynamic and rapid growth of the sector. NCSES decided to design and implement a new survey of nonprofits, and commissioned this workshop to provide a forum to discuss conceptual and design issues and methods.

Measuring Research and Development Expenditures in the U.S. Nonprofit Sector: Conceptual and Design Issues summarizes the presentations and discussion of the workshop. This report identifies concepts and issues for the design of a survey of R&D expenditures made by nonprofit organizations, considering the goals, content, statistical methodology, data quality, and data products associated with this data collection. The report also considers the broader usefulness of the data for understanding the nature of the nonprofit sector and their R&D activities. Measuring Research and Development Expenditures in the U. S. Nonprofit Sector will help readers understand the role of nonprofit sector given its enormous size and scope as well as its contribution to identifying new forms of R&D beyond production processes and new technology.

Solar panels reduce both global warming and urban heat island

March 24, 2015 Comments off

Solar panels reduce both global warming and urban heat island
Source: Frontiers in Environmental Science

The production of solar energy in cities is clearly a way to diminish our dependency to fossil fuels, and is a good way to mitigate global warming by lowering the emission of greenhouse gases. However, what are the impacts of solar panels locally? To evaluate their influence on urban weather, it is necessary to parameterize their effects within the surface schemes that are coupled to atmospheric models. The present paper presents a way to implement solar panels in the Town Energy Balance scheme, taking account of the energy production (for thermal and photovoltaic panels), the impact on the building below and feedback toward the urban micro-climate through radiative and convective fluxes. A scenario of large but realistic deployment of solar panels on the Paris metropolitan area is then simulated. It is shown that solar panels, by shading the roofs, slightly increases the need for domestic heating (3%). In summer, however, the solar panels reduce the energy needed for air-conditioning (by 12%) and also the Urban Heat Island (UHI): 0.2 K by day and up to 0.3 K at night. These impacts are larger than those found in previous works, because of the use of thermal panels (that are more efficient than photovoltaic panels) and the geographical position of Paris, which is relatively far from the sea. This means that it is not influenced by sea breezes, and hence that its UHI is stronger than for a coastal city of the same size. But this also means that local adaptation strategies aiming to decrease the UHI will have more potent effects. In summary, the deployment of solar panels is good both globally, to produce renewable energy (and hence to limit the warming of the climate) and locally, to decrease the UHI, especially in summer, when it can constitute a health threat.

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