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The accurate characterization of seasonal and inter-annual site-level wind energy variability is essential during wind project development. Understanding the features and probability of low-wind years is of particular interest to developers and financers. However, a dearth of long-term, hub-height wind observations makes these characterizations challenging, and thus techniques to improve these characterizations are of great value. To improve resource characterization, we explicitly link wind resource variability (at hub-height, and at specific sites) to regional and synoptic scale wind regimes. Our approach involves statistical clustering of high-resolution modeled wind data, and is applied to California for a period covering 1980–2015. With this approach, we investigate the unique meteorological patterns driving low and high wind years at five separate wind project sites. We also find wind regime changes over the 36-year period consistent with global warming: wind regimes associated with anomalously hot summer days increased at half a day per year and stagnant conditions increased at one-third days per year. Despite these changes, the average annual resource potential remained constant at all project sites. Additionally, we identify correlations between climate modes and wind regime frequency, a linkage valuable for resource characterization and forecasting. Our general approach can be applied in any location and may benefit many aspects of wind energy resource evaluation and forecasting.

The Teacher Assessment in Primary Science project is funded by the Primary Science Teaching Trust and based at Bath Spa University. The study aims to develop a whole-school model of valid, reliable and manageable teacher assessment to inform practice and make a positive impact on primary-aged children's learning in science. The model is based on a data-flow "pyramid" (analogous to the flow of energy through an ecosystem), whereby the rich formative assessment evidence gathered in the classroom is summarised for monitoring, reporting and evaluation purposes [Nuffield Foundation. (2012). "Developing policy, principles and practice in primary school science assessment." London: Nuffield Foundation]. Using a design-based research (DBR) methodology, the authors worked in collaboration with teachers from project schools and other expert groups to refine, elaborate, validate and operationalise the data-flow "pyramid" model, resulting in the development of a whole-school self-evaluation tool. In this paper, we argue that a DBR approach to theory-building and school improvement drawing upon teacher expertise has led to the identification, adaptation and successful scaling up of a promising approach to school self-evaluation in relation to assessment in science.

In April-July 2008, intensive measurements were made of atmospheric composition and chemistry in Sabah, Malaysia, as part of the "Oxidant and particle photochemical processes above a South-East Asian tropical rainforest" (OP3) project. Fluxes and concentrations of trace gases and particles were made from and above the rainforest canopy at the Bukit Atur Global Atmosphere Watch station and at the nearby Sabahmas oil palm plantation, using both ground-based and airborne measurements. Here, the measurement and modelling strategies used, the characteristics of the sites and an overview of data obtained are described. Composition measurements show that the rainforest site was not significantly impacted by anthropogenic pollution, and this is confirmed by satellite retrievals of NO2 and HCHO. The dominant modulators of atmospheric chemistry at the rainforest site were therefore emissions of BVOCs and soil emissions of reactive nitrogen oxides. At the observed BVOC:NOx volume mixing ratio (∼100 pptv/pptv), current chemical models suggest that daytime maximum OH concentrations should be ca. 105 radicals cm-3, but observed OH concentrations were an order of magnitude greater than this. We confirm, therefore, previous measurements that suggest that an unexplained source of OH must exist above tropical rainforest and we continue to interrogate the data to find explanations for this.

The Gulf of Carpentaria and Torres Strait in north‐eastern Australia support globally significant seagrass ecosystems that underpin fishing and cultural heritage of the region. Reliable data on seagrass distribution are critical to understanding how these ecosystems are changing, while managing for resilience. Spatial data on seagrass have been collected since the early 1980s, but the early data were poorly curated. Some was not publicly available, and some already lost. We validated and synthesized historical seagrass spatial data to create a publicly available database. We include a site layer of 48,612 geolocated data points including information on seagrass presence/absence, sediment, collection date, and data custodian. We include a polygon layer with 641 individual seagrass meadows. Thirteen seagrass species are identified in depths ranging from intertidal to 38 m below mean sea level. Our synthesis includes scientific survey data from 1983 to 2022 and provides an important evidence base for marine resource management. [ABSTRACT FROM AUTHOR]

Many students in general and advanced chemistry courses have difficulty understanding differences in solubility by inspecting changing values of the solubility product constants for sparingly soluble salts. In this demonstration, the concepts involved in understanding the solubility of sparingly soluble salts are illustrated visually. Utilizing bathocuproinedisulfonic acid in a mixed reducing reagent to complex copper(I), we are able to demonstrate to the naked eye copper(I) and copper(II) concentrations resulting from the dissolution of a variety of sparingly soluble copper compounds. The actual concentration of copper in solution can be determined using this visual demonstration in combination with a spectrophotometer. This demonstration visually confirms copper concentrations in the range of 1 x 10[superscript -3] to 1 x 10[superscript -6] M. Calculated solubilities based on a simple algorithm, neglecting secondary equilibria, ion-pair formation, and ionic effects, are in reasonable agreement with the measured solubilities. (Contains 1 table and 1 figure.)

Infants increasingly generalize deferred imitation across environmental contexts between 6 and 18 months of age. In three experiments with 126 6-, 9-, 12-, 15-, and 18-month-olds, we examined the role of the social context in deferred imitation. One experimenter demonstrated target actions on a hand puppet, and a second experimenter tested imitation 24h later. When the second experimenter was novel, infants did not exhibit deferred imitation at any age; when infants were preexposed to the second experimenter, all of them did. Imitating immediately after the demonstration also facilitated deferred imitation in a novel social context at all ages but 6 months. Infants' pervasive failure to exhibit deferred imitation in a novel social context may reflect evolutionary selection pressures that favored conservative behavior in social animals.

Increased atmospheric carbon dioxide leads to ocean acidification and carbon dioxide (CO.sub.2) enrichment of seawater. Given the important ecological functions of seagrass meadows, understanding their responses to CO.sub.2 will be critical for the management of coastal ecosystems. This study examined the physiological responses of three tropical seagrasses to a range of seawater pCO.sub.2 levels in a laboratory. Cymodocea serrulata, Halodule uninervis and Thalassia hemprichii were exposed to four different pCO.sub.2 treatments (442-1204 μatm) for 2 weeks, approximating the range of end-of-century emission scenarios. Photosynthetic responses were quantified using optode-based oxygen flux measurements. Across all three species, net productivity and energetic surplus (P.sub.G:R) significantly increased with a rise in pCO.sub.2 (linear models, P < 0.05). Photosynthesis-irradiance curve-derived photosynthetic parameters-maximum photosynthetic rates (P.sub.max) and efficiency (α)-also increased as pCO.sub.2 increased (linear models, P < 0.05). The response for productivity measures was similar across species, i.e. similar slopes in linear models. A decrease in compensation light requirement (E.sub.c) with increasing pCO.sub.2 was evident in C. serrulata and H. uninervis, but not in T. hemprichii. Despite higher productivity with pCO.sub.2 enrichment, leaf growth rates in C. serrulata did not increase, while those in H. uninervis and T. hemprichii significantly increased with increasing pCO.sub.2 levels. While seagrasses can be carbon-limited and productivity can respond positively to CO.sub.2 enrichment, varying carbon allocation strategies amongst species suggest differential growth response between species. Thus, future increase in seawater CO.sub.2 concentration may lead to an overall increase in seagrass biomass and productivity, as well as community changes in seagrass meadows., Author(s): Y. X. Ow[sup.1] [sup.2] , C. J. Collier[sup.1] [sup.3] , S. Uthicke[sup.2] Author Affiliations: (1) College of Marine and Environmental Science, James Cook University, 4811, Townsville, QLD, Australia (2) [...]