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Threats from climate change are increasing for Natural World Heritage Sites
No full textThe aim of the paper is to analyse the occurrence and intensity of threats to Natural World Heritage Sites from climate change as assessed by IUCN experts. The data comes from the Conservation Outlook Assessment database, which covers 250 sites for three time periods (2014, 2017 and 2020). The threat of climate change is broadly defined and includes temperature extremes, rapidly disappearing glaciers, coral bleaching, droughts, desertification, rising temperatures and rising sea levels. Simultaneous probit and ordered models with individual site effects are used to analyse the occurrence and intensity of both a perceived actual and a potential threat.
The estimates show that both the occurrence of a current climate change threat and its intensity increase significantly over time when site characteristics and location are taken into account. An important finding of the study is that the likelihood of a climate change threat not only increases over time, but also depends on the type and characteristics of the location. The probability of a current climate threat is highest in marine and coastal areas and lowest in desert areas. The probability of an actual climate threat is significantly lower for locations in Africa, while the probability of a potential climate threat is highest in Latin America.
Keywords: Climate Change, threats, expert assessment, marine and coastal sites, Natural World Heritage sites, Probit and ordered probit model
104. I-69 ORX Section 3: Completing the Connection
Get PDFThe I-69 Ohio River Crossing (ORX) will be a key, final connection of I-69 between Evansville, Indiana and Henderson, Kentucky. The transformational project includes three contracts, two states and one much-anticipated new river crossing. In this session, you will hear an update on the ORX project as a whole and learn about I-69 ORX Section 3
Compressed Natural Gas and How It Works
Get PDFJoin us for a discussion about compressed natural gas (CNG) and how it works. Attendees will learn safety measures, where CNG works and where it doesn’t, cost and operation comparisons, fuel efficiency, infrastructure, emissions, and garage modifications
It Starts with You: Effective Team Building Strategies
Get PDFThis presentation will provide strategies to build effective teams. Transportation projects require effective collaboration, which is accomplished through team building and trust. To successfully manage and work in a team made up of diverse people with different perspectives and experiences, we must first look inward to build self-awareness and emotional intelligence. In doing so, we can connect with others by being our authentic selves and listening to understand
Runway 1-19: Greensburg Municipal Airport’s New 5,405-ft Runway:
Get PDFThe Greensburg Municipal Airport completed the construction of Runway 1-19 on a new alignment in 2022. Runway 1-19 is 5,405-ft long × 100-ft wide and replaced the existing Runway 18-36 that was 3,430-ft long × 40-ft wide. This was a multi-year construction project with a broad scope that included land acquisition; construction in a flood-way; grading and drainage; paving and electrical; and extensive FAA coordination. Challenges and successes will be discussed
Evaluation of critical weed-free period for three sweetpotato (Ipomoea batatas) cultivars
Get PDFSweetpotato [Ipomoea batatas (L.) Lam.] is a staple crop that provides nutritional benefits to humans globally, but it is subject to yield loss when competing with weeds, especially during the early stage of establishment. Yield loss can vary widely based on the cultivar, production environment, weed species, and management techniques. To address this challenge, we conducted field research at the Samuel G. Meigs Horticulture Research Farm, Lafayette, IN, and at the Southwest Purdue Agricultural Center, Vincennes, IN, in 2022 to determine the effect of sweetpotato cultivar on the critical weed-free period. The experiment was a split-plot design, with weed-free interval treatments as the main plot factor and cultivar as the subplot factor. The three cultivars used were ‘Covington’, ‘Monaco’, and ‘Murasaki’. Weeds were removed by hand and allowed to establish and compete with the crop beginning at 0, 14, 21, 28, 35, or 42 d after transplanting (DAP). As the weed-free interval increased from 0 to 42 DAP, predicted total yield increased from 19 kg ha−1 to 20,540 kg ha−1 for Covington, 3 kg ha−1 to 11,407 kg ha−1 for Monaco, and 125 kg ha−1 to 13,460 kg ha−1 for Murasaki at the Lafayette location. At Vincennes, as the weed-free interval increased from 0 to 42 DAP, predicted total yield increased from 14,664 kg ha−1 to 33,905 kg ha−1 for Covington, 4,817 kg ha−1 to 18,059 kg ha−1 for Monaco, and 12,735 kg ha−1 to 21,105 kg ha−1 for Murasaki. A threshold of ≤10% total yield reduction was achieved by maintaining sweetpotatoes weed-free 24 DAP for Covington, 20 DAP for Murasaki, and 33 DAP for Monaco
The Acoustics of Absorbers Comprising a Flexible Perforated Membrane Backed by a Stack of Granular Material
Get PDFIt has been found that when a layer of activated carbon partially fills the space behind a finite, edge-constrained, tensioned impermeable membrane, the absorption peaks due to the modal response of the membrane can be significantly enhanced in the low frequency range. In the present work, the modeling aspects of the latter work have been extended to allow the membrane to be both tensioned and flexurally-stiff, and further, to be micro-perforated, thus expanding the treatment design space. Secondly, the particle layer behind the membrane is modeled by using a two-dimensional finite difference implementation of the Biot poro-elastic theory which then accounts for the interaction of the particle layer and walls that contain it: i.e., the solid phase of the particle stack itself is allowed to exhibit modal behavior in the radial direction. The interaction of the membrane nearfield and the particle stack, which creates a nearfield damping effect, is also fully captured. Finally, the model accounts for the hierarchical porosity of activated carbon. The model has been verified by comparison with measurements and it has been found that strikingly high levels of low frequency absorption can be realized by appropriate optimization of the membrane and particle stack properties and geometry
Dynamics of an Airplane Wheel at Touchdown
Get PDFThe dynamics of tire skidding and wear of a commercial airplane during touchdown is discussed, and a simple analytical model is presented. It is suggested that prespinning of the wheels prior to touchdown is not only possible but also practical to prevent tire wear and damage to the runway and the ensuing environmental issues