816 research outputs found

    The Saharan heat low and moisture transport pathways in the central Sahara-multiaircraft observations and Africa-LAM evaluation

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    We present a characterization of the Saharan heat low (SHL) based on dropsonde observations made on 22 June 2011 by two simultaneously flying aircraft during the Fennec project. The observations are used to identify moisture transport pathways and to validate the UK Met Office limited area model for northern Africa (Africa-LAM). The observations capture the SHL, harmattan, and monsoon surge. The SHL has a northeast-southwest orientated elongated shape centered over northern Mauritania. The SHL core is associated with a 950 hPa temperature minimum (36.4°C) in the morning caused by the monsoon surge and a maximum (42.6°C) in the afternoon. The monsoon surge east of the SHL core splits into two transport pathways: (a) curving around the SHL core in the north, especially pronounced in a morning near-surface layer, and (b) northeastward transport within the ~2km deep monsoon surge (afternoon observations only). In the morning the model forecasts the harmattan, monsoon surge, and the SHL geographic location and northeast-southwest orientation well but the model represents the SHL flatter and more spatially extended and overestimates the convective boundary layer (CBL) by up to ~0.3 km. The simulated afternoon SHL location appears shifted westward by up to ~1°. The model overestimates the shallow afternoon monsoon surge CBL depth of ~1.8km by >2kmresulting in southwestward transport of vertically mixed moisture above ~2.5km contrasting observed northeastward-only transport at lower levels. This moisture distribution model error is likely to have consequences for simulations of Saharan thermodynamics and dust emissions caused by convection-driven cold pools

    Assessing the Impact of a Geospatial Data Collection App on Student Engagement in Environmental Education

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    A critical component of environmental education is to ensure student understanding and use of available technologies to better experience and analyze spatially distributed features of the environment. Combining mobile technologies with geographic information systems in field data collection may provide a unique opportunity for students to feel engaged in what they are learning and take ownership of their learning process. We customized an open access data collection application using Collector for ArcGIS and investigated its impacts on student engagement and perception of the incorporation of technology within an environmental science curriculum. Analyses of pre- and post-surveys indicate that the inclusion of geospatial technologies as a part of environmental curricula allows students to take the lead on their own research, view field data interactively as opposed to looking at a database in hindsight and analyze multiscale data as it is presented during field data collection. The findings of this study are consistent with previous studies, suggesting a strong association between the inclusion of geospatial technologies as a part of curricula and student engagement

    Human Powered Vehicle Capstone

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    In the ASME Human Powered Vehicle Challenge (HPVC), students design, develop, construct, and test different designs of human-powered vehicles. The design utilizes two wheels, the rear of which is responsible for power transmission from a pedal crank and braking through a disc and caliper. The design also utilizes the front wheel fork wheel for steering. Steering and braking are controlled by two levers on the handlebars. To determine whether the design was sufficient, it was compared to the standards set by ASME, including maximum weight, minimum speed, minimum turning radius, minimum ride distance, load testing, harness verification, and a complete rollover protection system. Assembling the design consisted of welding the unique frame and attaching all parts which includes wheels, gears, chains, a seat, and a harness. Testing the design was done by applying the specified loads after assembly, which was not able to be completed at the time of the report. Speed testing was done by using a GPS spedometer while riding the bike, and the vehicle met speed standards. Testing of the brakes was done similarly and braking distance was measured once the bicycle met the desired speed, which the vehicle passed. Sustained travel testing was done by attempting to ride the bike without assistance, but this failed. All other testing was done by inspection of the vehicle, including turning radius, harness, and proper functioning of the rollover protection system. Overall, the vehicle would have failed to compete in the HPVC due to its inability to travel without assistance

    Rodeo: The Greatest Show on Earth

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    Talk by UW History Professor Emeritus Mike Allen in conjunction with the annual Ellensburg Rodeo.https://digitalcommons.cwu.edu/libraryevents/1165/thumbnail.jp

    Mt. Apo Natural Park in the Southern Philippines Using Terrestrial LiDAR System

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    Extraction of plot-level field measurements entails a rigid and time-consuming task. Fine resolution remote sensing technology offers an objective and consistent method for estimation of forest vertical structures. We explored the development of algorithms for estimating above ground biomass (AGB) at the plot level using terrestrial LiDAR system (TLS). This research follows IPCC Tier 2 approach, by combining field and remote sensing data, in estimating forest carbon stocks. Permanent plots (30 × 30 m diameter) were established inside Mt. Apo Natural Park. Forest inventory was conducted in July 2013, recording tree heights and stem diameters for all hardwood species with diameter at breast height (DBH) ≄ 5 cm in three management zones: multiple use, strict protection, and restoration. Quadratic mean stem diameter was employed for large DBH intervals for deriving midpoint biomass. Three tropical allometric equations were used to derive referenced biomass values. Regressions results showed satisfactory modeling fit in relating plot-level AGB to DBH class size: 80%–89%. Mean tree heights from field and TLS data were related showing R2 = 88%. TLS variables derived include percentile heights and normalized height bins at 5-m intervals. The generalized linear model is a more robust model for percentile heights, while stepwise regression showed a better regression performance for normalized height bins. Strict protection zone contained the highest carbon storage. This study demonstrated the significant TLS-derived metrics to assess plot-level biomass. TLS scanning is also the first work to be done in this ASEAN Natural Heritage Park, which is constrained with local insurgency problems. Biomass in plot-level can be used to extrapolate to landscape-level using available multispectral or radar imagery

    Monitoring Vegetation Dynamics and Carbon Stock Density in Miombo Woodlands

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    Background The United Nation’s Program for Reducing Emissions from Deforestation and Forest Degradation (REDD+) aims to reduce the 20% contribution to global emissions of greenhouse gases from the forest sector, offering a financial value of the carbon stored in forests as an incentive for local communities. The pre-requisite for the setup of a participatory REDD + Program is the monitoring, reporting and verification (MRV) of baseline carbon stocks and their changes over time. In this study, we investigated miombo woodland’s dynamics in terms of composition, structure and biomass over a 4-year period (2005–2009), and the Carbon Stock Density (CSD) for the year 2009. The study was conducted in the Niassa National Reserve (NNR) in northern Mozambique, which is the 14th largest protected area in the world. Results Mean tree density distributed across 79 species increased slightly between 2005 and 2009, respectively, from 548 to 587 trees ha-1. Julbernardia globiflora (Benth.) was the most important species in this area [importance value index (IVI2005= 61 and IVI2009 = 54)]. The woodlands presented an inverted J-shaped diametric curve, with 69% of the individuals representing the young cohort. Woody biomass had a net increase of 3 Mg ha-1 with the highest growth observed in Dyplorhynchus condilocarpon (MĂŒll.Arg.) Pichon (0.54 Mg ha-1). J. globiflora had a net decrease in biomass of 0.09 Mg ha-1. Total CSD density was estimated at ca. 67 MgC ha-1 ± 24.85 with soils (average 34.72 ± 17.93 MgC ha-1) and woody vegetation (average 29.8 MgC ha-1 ± 13.07) representing the major carbon pools. The results point to a relatively stable ecosystem, but they call for the need to refocus management activities. Conclusions The miombo woodlands in NNR are representative of the woodlands in the eco-region in terms of vegetation structure and composition. They experienced net increase in woody biomass, a considerable recruitment level and low mortality. According to our results, NNR may present good potential for carbon sequestration especially in soils and woody biomass, representing an important potential carbon sink. However, further investigations are needed in order to address the contribution of this area to MRV REDD + initiatives

    Stakeholder Voice in Water Resource Planning

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    Stakeholder engagement for natural resource management at the state and local levels has become an important governance practice. This study examines the association of individual traits (aggressive communication, comfort with technology, and argumentativeness) with stakeholder participant voice in a water basin planning virtual meeting setting. Individual participants of the Edisto River Basin Council (RBC) meetings are the subject of the study. South Carolina decentralized water planning to the river basin level, creating RBCs and appointing interested and relevant stakeholders as members. While the river basin planning process did not envisage virtual (Zoom) meetings for the regular meetings of the RBC, the COVID pandemic required this to begin the planning process. Moreover, meeting participants possess diverse interests, powers, and individual traits that may affect the use of voice and engagement. There is well-established literature on stakeholder participation in resource planning. However, there are gaps in the literature regarding use of voice in virtual meeting settings in water resources planning, especially in settings like water-abundant areas in the Southeastern United States. Using the Edisto RBC as a pilot basin and quantitative surveys, preliminary results found that while RBC participants were on average comfortable with technology, they generally avoided conflict, they exhibited average communication apprehension in a meeting environment, and virtual meetings appear to limit participant’s use of voice. Consequently, meeting planners must recognize that not all participants express themselves optimally in virtual meeting settings. In this vein, planners must work to develop opportunities for as much active engagement and sharing as possible
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