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03:20 Institute of Physics (IOP) English 2018

Climate effects of non-compliant Volkswagen diesel cars

On-road operations of Volkswagen light-duty diesel vehicles equipped with defeat devices cause emissions of NOx up to 40 times above emission standards. Higher on-road NOx emissions are a widespread problem not limited to Volkswagen vehicles, but the Volkswagen violations brought this issue under the spotlight. While several studies investigated the health impacts of high NOx emissions, the climatic impacts have not been quantified. Here we show that such diesel cars generate a larger warming on the time scale of several years but a smaller warming on the decadal time scale during actual on-road operations than in vehicle certification tests. The difference in longer-term warming levels, however, depends on underlying driving conditions. Furthermore, in the presence of defeat devices, the climatic advantage of 'clean diesel' cars over gasoline cars, in terms of global-mean temperature change, is in our view not necessarily the case.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
02:17 Institute of Physics (IOP) English 2018

Feed conversion efficiency in aquaculture: do we measure it correctly?

Globally, demand for food animal products is rising. At the same time, we face mounting, related pressures including limited natural resources, negative environmental externalities, climate disruption, and population growth. Governments and other stakeholders are seeking strategies to boost food production efficiency and food system resiliency, and aquaculture (farmed seafood) is commonly viewed as having a major role in improving global food security based on longstanding measures of animal production efficiency. The most widely used measurement is called the 'feed conversion ratio' (FCR), which is the weight of feed administered over the lifetime of an animal divided by weight gained. By this measure, fed aquaculture and chickens are similarly efficient at converting feed into animal biomass, and both are more efficient compared to pigs and cattle. FCR does not account for differences in feed content, edible portion of an animal, or nutritional quality of the final product. Given these limitations, we searched the literature for alternative efficiency measures and identified 'nutrient retention', which can be used to compare protein and calories in feed (inputs) and edible portions of animals (outputs). Protein and calorie retention have not been calculated for most aquaculture species. Focusing on commercial production, we collected data on feed composition, feed conversion ratios, edible portions (i.e. yield), and nutritional content of edible flesh for nine aquatic and three terrestrial farmed animal species. We estimate that 19% of protein and 10% of calories in feed for aquatic species are ultimately made available in the human food supply, with significant variation between species. Comparing all terrestrial and aquatic animals in the study, chickens are most efficient using these measures, followed by Atlantic salmon. Despite lower FCRs in aquaculture, protein and calorie retention for aquaculture production is comparable to livestock production. This is, in part, due to farmed fish and shrimp requiring higher levels of protein and calories in feed compared to chickens, pigs, and cattle. Strategies to address global food security should consider these alternative efficiency measures.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
02:38 Institute of Physics (IOP) English 2018

The asymmetric response of Yangtze river basin summer rainfall to El Niño/La Niña

The Yangtze river basin, in South East China, experiences anomalously high precipitation in summers following El Niño. This can lead to extensive flooding and loss of life. However, the response following La Niña has not been well documented. In this study, the response of Yangtze summer rainfall to El Niño/La Niña is found to be asymmetric, with no significant response following La Niña. The nature of this asymmetric response is found to be in good agreement with that simulated by the Met Office seasonal forecast system. Yangtze summer rainfall correlates positively with spring sea surface temperatures in the Indian Ocean and northwest Pacific. Indian Ocean sea surface temperatures are found to respond linearly to El Niño/La Niña, and to have a linear impact on Yangtze summer rainfall. However, northwest Pacific sea surface temperatures respond much more strongly following El Niño and, further, correlate more strongly with positive rainfall years. It is concluded that, whilst delayed Indian Ocean signals may influence summer Yangtze rainfall, it is likely that they do not lead to the asymmetric nature of the rainfall response to El Niño/La Niña.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:55 Institute of Physics (IOP) English 2018

Impact of cutting meat intake on hidden greenhouse gas emissions in an import-reliant city

Greenhouse gas emissions embodied in trade is a growing concern for the international community. Multiple studies have highlighted drawbacks in the territorial and production-based accounting of greenhouse gas emissions because it neglects emissions from the consumption of goods in trade. This creates weak carbon leakage and complicates international agreements on emissions regulations. Therefore, we estimated consumption-based emissions using input-output analysis and life cycle assessment to calculate the greenhouse gas emissions hidden in meat and dairy products in Hong Kong, a city predominately reliant on imports. We found that emissions solely from meat and dairy consumption were higher than the city's total greenhouse gas emissions using conventional production-based calculation. This implies that government reports underestimate more than half of the emissions, as 62% of emissions are embodied in international trade. The discrepancy emphasizes the need of transitioning climate targets and policy to consumption-based accounting. Furthermore, we have shown that dietary change from a meat-heavy diet to a diet in accordance with governmental nutrition guidelines could achieve a 67% reduction in livestock-related emissions, allowing Hong Kong to achieve the Paris Agreement targets for 2030. Consequently, we concluded that consumption-based accounting for greenhouse gas emissions is crucial to target the areas where emissions reduction is realistically achievable, especially for import-reliant cities like Hong Kong.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
01:26 Institute of Physics (IOP) English 2018

Saharan dust plume charging observed over the UK

A plume of Saharan dust and Iberian smoke was carried across the southern UK on 16th October 2017, entrained into an Atlantic cyclone which had originated as Hurricane Ophelia. The dust plume aloft was widely noticed as it was sufficiently dense to redden the visual appearance of the sun. Time series of backscatter from ceilometers at Reading and Chilbolton show two plumes: one carried upwards to 2.5 km, and another below 800 m into the boundary layer, with a clear slot between. Steady descent of particles at about 50 cm s−1 continued throughout the morning, and coarse mode particles reached the surface. Plumes containing dust are frequently observed to be strongly charged, often through frictional effects. This plume passed over atmospheric electric field sensors at Bristol, Chilbolton and Reading. Consistent measurements at these three sites indicated negative plume charge. The lower edge plume charge density was (−8.0 ± 3.3) nC m−2, which is several times greater than that typical for stratiform water clouds, implying an active in situ charge generation mechanism such as turbulent triboelectrification. A meteorological radiosonde measuring temperature and humidity was launched into the plume at 1412 UTC, specially instrumented with charge and turbulence sensors. This detected charge in the boundary layer and in the upper plume region, and strong turbulent mixing was observed throughout the atmosphere's lowest 4 km. The clear slot region, through which particles sedimented, was anomalously dry compared with modelled values, with water clouds forming intermittently in the air beneath. Electrical aspects of dust should be included in numerical models, particularly the charge-related effects on cloud microphysical properties, to accurately represent particle behaviour and transport.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:44 Institute of Physics (IOP) No linguistic content; Not applicable 2018

Monitoring multi-year macro ocean litter dynamics and backward-tracking simulation of litter origins on a remote island in the South China Sea

Ocean litter has accumulated rapidly and is becoming a major environmental concern, yet quantitative and regular observations and exploration that track litter origins are limited. By implementing monthly sample collections over five years (2012–2016) at Dongsha Island, a remote island in the northern South China Sea (SCS), we assessed macro ocean litter dynamics, identified source countries of individual plastic bottles, and analyzed the origins of the litter by a backward-tracking model simulation considering both the effects of current velocity and windage. The results showed that large amounts of litter, which varied monthly and annually in weight and quantity, reached the island during the study years, and there were spatial differences in accumulation patterns between the north and south coasts. Styrofoam and plastic bottles were the two primary sources of macro ocean litter both annually and monthly, and most of the litter collected on the island originated from China and Vietnam, which were collectively responsible for approximately 47.5%–63.7% per month. The simulation indicated that current advection at the near-surface depths and low windage at the sea surface showed similar patterns, while medium to high windage exhibited comparable expression patterns in response to potential source regions and drifting time experiments. At either the surface with low windage or current advection at depths of 0.5 m and 1 m, macro ocean litter in the Western Philippine Sea, i.e. through the Luzon Strait between Taiwan and the Philippines, was an important contributor to the litter bulk from October to March, whereas the litter was predicted to mainly originate from the southwestern SCS from April to September. With an increasing windage effect, litter in the Taiwan Strait was predicted to be an additional major potential source. Surprisingly, a small proportion of the macro ocean litter was predicted to continuously travel in the northern SCS for a long duration (> 2 years) before drifting onto Dongsha Island. The estimated drifting time of macro ocean litter also showed monthly and directional variability. This study demonstrated that a tremendous quantity of macro ocean litter, which may cause great damage to the marine ecosystem, drifts in the ocean surface layer and is finally pushed onto beaches. Therefore, we proposed an action plan for effective ocean litter management development at regional and global spatial scales, which is vital for improving and restoring the health and sustainability of the oceanic environment.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: No linguistic content; Not applicable
02:24 Institute of Physics (IOP) English 2018

Global predictability of temperature extremes

Extreme temperatures are one of the leading causes of death and disease in both developed and developing countries, and heat extremes are projected to rise in many regions. To reduce risk, heatwave plans and cold weather plans have been effectively implemented around the world. However, much of the world's population is not yet protected by such systems, including many data-scarce but also highly vulnerable regions. In this study, we assess at a global level where such systems have the potential to be effective at reducing risk from temperature extremes, characterizing (1) long-term average occurrence of heatwaves and coldwaves, (2) seasonality of these extremes, and (3) short-term predictability of these extreme events three to ten days in advance. Using both the NOAA and ECMWF weather forecast models, we develop global maps indicating a first approximation of the locations that are likely to benefit from the development of seasonal preparedness plans and/or short-term early warning systems for extreme temperature. The extratropics generally show both short-term skill as well as strong seasonality; in the tropics, most locations do also demonstrate one or both. In fact, almost 5 billion people live in regions that have seasonality and predictability of heatwaves and/or coldwaves. Climate adaptation investments in these regions can take advantage of seasonality and predictability to reduce risks to vulnerable populations.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:48 Institute of Physics (IOP) English 2018

A decade of remotely sensed observations highlight complex processes linked to coastal permafrost bluff erosion in the Arctic

Eroding permafrost coasts are likely indicators and integrators of changes in the Arctic System as they are susceptible to the combined effects of declining sea ice extent, increases in open water duration, more frequent and impactful storms, sea-level rise, and warming permafrost. However, few observation sites in the Arctic have yet to link decadal-scale erosion rates with changing environmental conditions due to temporal data gaps. This study increases the temporal fidelity of coastal permafrost bluff observations using near-annual high spatial resolution (<1 m) satellite imagery acquired between 2008–2017 for a 9 km segment of coastline at Drew Point, Beaufort Sea coast, Alaska. Our results show that mean annual erosion for the 2007–2016 decade was 17.2 m yr−1, which is 2.5 times faster than historic rates, indicating that bluff erosion at this site is likely responding to changes in the Arctic System. In spite of a sustained increase in decadal-scale mean annual erosion rates, mean open water season erosion varied from 6.7 m yr−1 in 2010 to more than 22.0 m yr−1 in 2007, 2012, and 2016. This variability provided a range of coastal responses through which we explored the different roles of potential environmental drivers. The lack of significant correlations between mean open water season erosion and the environmental variables compiled in this study indicates that we may not be adequately capturing the environmental forcing factors, that the system is conditioned by long-term transient effects or extreme weather events rather than annual variability, or that other not yet considered factors may be responsible for the increased erosion occurring at Drew Point. Our results highlight an increase in erosion at Drew Point in the 21st century as well as the complexities associated with unraveling the factors responsible for changing coastal permafrost bluffs in the Arctic.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:15 Institute of Physics (IOP) English 2018

Deconstructing climate misinformation to identify reasoning errors

Misinformation can have significant societal consequences. For example, misinformation about climate change has confused the public and stalled support for mitigation policies. When people lack the expertise and skill to evaluate the science behind a claim, they typically rely on heuristics such as substituting judgment about something complex (i.e. climate science) with judgment about something simple (i.e. the character of people who speak about climate science) and are therefore vulnerable to misleading information. Inoculation theory offers one approach to effectively neutralize the influence of misinformation. Typically, inoculations convey resistance by providing people with information that counters misinformation. In contrast, we propose inoculating against misinformation by explaining the fallacious reasoning within misleading denialist claims. We offer a strategy based on critical thinking methods to analyse and detect poor reasoning within denialist claims. This strategy includes detailing argument structure, determining the truth of the premises, and checking for validity, hidden premises, or ambiguous language. Focusing on argument structure also facilitates the identification of reasoning fallacies by locating them in the reasoning process. Because this reason-based form of inoculation is based on general critical thinking methods, it offers the distinct advantage of being accessible to those who lack expertise in climate science. We applied this approach to 42 common denialist claims and find that they all demonstrate fallacious reasoning and fail to refute the scientific consensus regarding anthropogenic global warming. This comprehensive deconstruction and refutation of the most common denialist claims about climate change is designed to act as a resource for communicators and educators who teach climate science and/or critical thinking.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:02 Institute of Physics (IOP) English 2018

How big is the energy efficiency resource?

Most economic theorists assume that energy efficiency—the biggest global provider of energy services—is a limited and dwindling resource whose price- and policy-driven adoption will inevitably deplete its potential and raise its cost. Influenced by that theoretical construct, most traditional analysts and deployers of energy efficiency see and exploit only a modest fraction of the worthwhile efficiency resource, saving less and paying more than they should. Yet empirically, modern energy efficiency is, and shows every sign of durably remaining, an expanding-quantity, declining-cost resource. Its adoption is constrained by major but correctable market failures and increasingly motivated by positive externalities. Most importantly, in both newbuild and retrofit applications, its quantity is severalfold larger and its cost lower than most in the energy and climate communities realize. The efficiency resource far exceeds the sum of savings by individual technologies because artfully choosing, combining, sequencing, and timing fewer and simpler technologies can save more energy at lower cost than deploying more and fancier but dis-integrated and randomly timed technologies. Such 'integrative design' is not yet widely known or applied, and can seem difficult because it is simple, but is well proven, rapidly evolving, and gradually spreading. Yet the same economic models that could not predict the renewable energy revolution also ignore integrative design and hence cannot recognize most of the efficiency resource or reserves. This analytic gap makes climate-change mitigation look harder and costlier than it really is, diverting attention and investment to inferior options. With energy efficiency as its cornerstone and needing its pace redoubled, climate protection depends critically on seeing and deploying the entire efficiency resource. This requires focusing less on individual technologies than on whole systems (buildings, factories, vehicles, and the larger systems embedding them), and replacing theoretical assumptions about efficiency's diminishing returns with practitioners' empirical evidence of expanding returns.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:52 Institute of Physics (IOP) English 2018

Estimates of present and future flood risk in the conterminous United States

Past attempts to estimate rainfall-driven flood risk across the US either have incomplete coverage, coarse resolution or use overly simplified models of the flooding process. In this paper, we use a new 30 m resolution model of the entire conterminous US with a 2D representation of flood physics to produce estimates of flood hazard, which match to within 90% accuracy the skill of local models built with detailed data. These flood depths are combined with exposure datasets of commensurate resolution to calculate current and future flood risk. Our data show that the total US population exposed to serious flooding is 2.6–3.1 times higher than previous estimates, and that nearly 41 million Americans live within the 1% annual exceedance probability floodplain (compared to only 13 million when calculated using FEMA flood maps). We find that population and GDP growth alone are expected to lead to significant future increases in exposure, and this change may be exacerbated in the future by climate change.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:02 Institute of Physics (IOP) English 2018

Are Scots pine forest edges particularly prone to drought-induced mortality?

Climate change is expected to exacerbate the frequency of drought-induced tree mortality world-wide. To better predict the associated change of species composition and forest dynamics on various scales and develop adequate adaptation strategies, more information on the mechanisms driving the often observed patchiness of tree die-back is needed. Although forest-edge effects may play an important role within the given context, only few corresponding studies exist. Here, we investigate the regional die-back of Scots pine in Franconia, Germany, after a hot and dry summer in 2015, thereby emphasizing possible differences in mortality between forest edge and interior. By means of dendroecological investigations and close-range remote sensing, we assess long-term growth performance and current tree vitality along five different forest-edge distance gradients. Our results clearly indicate a differing growth performance between edge and interior trees, associated with a higher vulnerability to drought, increased mortality rates, and lower tree vitality at the forest edge. Prior long-lasting growth decline of dead trees compared to live trees suggests depletion of carbon reserves in course of a long-term drought persisting since the 1990s to be the cause of regional Scots pine die-back. These findings highlight the forest edge as a potential focal point of forest management adaptation strategies in the context of drought-induced mortality.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:32 Institute of Physics (IOP) English 2018

Phenological mismatch in coastal western Alaska may increase summer season greenhouse gas uptake

High latitude ecosystems are prone to phenological mismatches due to climate change- driven advances in the growing season and changing arrival times of migratory herbivores. These changes have the potential to alter biogeochemical cycling and contribute to feedbacks on climate change by altering greenhouse gas (GHG) emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) through large regions of the Arctic. Yet the effects of phenological mismatches on gas fluxes are currently unexplored. We used a three-year field experiment that altered the start of the growing season and timing of grazing to investigate how phenological mismatch affects GHG exchange. We found early grazing increased mean GHG emission to the atmosphere despite lower CH4 emissions due to grazing-induced changes in vegetation structure that increased uptake of CO2. In contrast, late grazing reduced GHG emissions because greater plant productivity led to an increase in CO2 uptake that overcame the increase in CH4 emission. Timing of grazing was an important control on both CO2 and CH4 emissions, and net GHG exchange was the result of opposing fluxes of CO2 and CH4. N2O played a negligible role in GHG flux. Advancing the growing season had a smaller effect on GHG emissions than changes to timing of grazing in this study. Our results suggest that a phenological mismatch that delays timing of grazing relative to the growing season, a change which is already developing along in western coastal Alaska, will reduce GHG emissions to the atmosphere through increased CO2 uptake despite greater CH4 emissions.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:03 Institute of Physics (IOP) English 2018

Greenhouse gas emissions and energy use associated with production of individual self-selected US diets

Human food systems are a key contributor to climate change and other environmental concerns. While the environmental impacts of diets have been evaluated at the aggregate level, few studies, and none for the US, have focused on individual self-selected diets. Such work is essential for estimating a distribution of impacts, which, in turn, is key to recommending policies for driving consumer demand towards lower environmental impacts. To estimate the impact of US dietary choices on greenhouse gas emissions (GHGE) and energy demand, we built a food impacts database from an exhaustive review of food life cycle assessment (LCA) studies and linked it to over 6000 as-consumed foods and dishes from 1 day dietary recall data on adults (N = 16 800) in the nationally representative 2005–2010 National Health and Nutrition Examination Survey. Food production impacts of US self-selected diets averaged 4.7 kg CO2 eq. person−1 day−1 (95% CI: 4.6–4.8) and 25.2 MJ non-renewable energy demand person−1 day−1 (95% CI: 24.6–25.8). As has been observed previously, meats and dairy contribute the most to GHGE and energy demand of US diets; however, beverages also emerge in this study as a notable contributor. Although linking impacts to diets required the use of many substitutions for foods with no available LCA studies, such proxy substitutions accounted for only 3% of diet-level GHGE. Variability across LCA studies introduced a ±19% range on the mean diet GHGE, but much of this variability is expected to be due to differences in food production locations and practices that can not currently be traced to individual dietary choices. When ranked by GHGE, diets from the top quintile accounted for 7.9 times the GHGE as those from the bottom quintile of diets. Our analyses highlight the importance of utilizing individual dietary behaviors rather than just population means when considering diet shift scenarios.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:08 Institute of Physics (IOP) English 2018

A new NDVI measure that overcomes data sparsity in cloud-covered regions predicts annual variation in ground-based estimates of high arctic plant productivity

Efforts to estimate plant productivity using satellite data can be frustrated by the presence of cloud cover. We developed a new method to overcome this problem, focussing on the high-arctic archipelago of Svalbard where extensive cloud cover during the growing season can prevent plant productivity from being estimated over large areas. We used a field-based time-series (2000−2009) of live aboveground vascular plant biomass data and a recently processed cloud-free MODIS-Normalised Difference Vegetation Index (NDVI) data set (2000−2014) to estimate, on a pixel-by-pixel basis, the onset of plant growth. We then summed NDVI values from onset of spring to the average time of peak NDVI to give an estimate of annual plant productivity. This remotely sensed productivity measure was then compared, at two different spatial scales, with the peak plant biomass field data. At both the local scale, surrounding the field data site, and the larger regional scale, our NDVI measure was found to predict plant biomass (adjusted R 2 = 0.51 and 0.44, respectively). The commonly used 'maximum NDVI' plant productivity index showed no relationship with plant biomass, likely due to some years having very few cloud-free images available during the peak plant growing season. Thus, we propose this new summed NDVI from onset of spring to time of peak NDVI as a proxy of large-scale plant productivity for regions such as the Arctic where climatic conditions restrict the availability of cloud-free images.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:07 Institute of Physics (IOP) English 2018

Quantifying long-term changes in carbon stocks and forest structure from Amazon forest degradation

Despite sustained declines in Amazon deforestation, forest degradation from logging and fire continues to threaten carbon stocks, habitat, and biodiversity in frontier forests along the Amazon arc of deforestation. Limited data on the magnitude of carbon losses and rates of carbon recovery following forest degradation have hindered carbon accounting efforts and contributed to incomplete national reporting to reduce emissions from deforestation and forest degradation (REDD+). We combined annual time series of Landsat imagery and high-density airborne lidar data to characterize the variability, magnitude, and persistence of Amazon forest degradation impacts on aboveground carbon density (ACD) and canopy structure. On average, degraded forests contained 45.1% of the carbon stocks in intact forests, and differences persisted even after 15 years of regrowth. In comparison to logging, understory fires resulted in the largest and longest-lasting differences in ACD. Heterogeneity in burned forest structure varied by fire severity and frequency. Forests with a history of one, two, and three or more fires retained only 54.4%, 25.2%, and 7.6% of intact ACD, respectively, when measured after a year of regrowth. Unlike the additive impact of successive fires, selective logging before burning did not explain additional variability in modeled ACD loss and recovery of burned forests. Airborne lidar also provides quantitative measures of habitat structure that can aid the estimation of co-benefits of avoided degradation. Notably, forest carbon stocks recovered faster than attributes of canopy structure that are critical for biodiversity in tropical forests, including the abundance of tall trees. We provide the first comprehensive look-up table of emissions factors for specific degradation pathways at standard reporting intervals in the Amazon. Estimated carbon loss and recovery trajectories provide an important foundation for assessing the long-term contributions from forest degradation to regional carbon cycling and advance our understanding of the current state of frontier forests.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:02 Institute of Physics (IOP) English 2018

Global sea-level contribution from Arctic land ice: 1971–2017

The Arctic Monitoring and Assessment Program (AMAP 2017) report identifies the Arctic as the largest regional source of land ice to global sea-level rise in the 2003–2014 period. Yet, this contextualization ignores the longer perspective from in situ records of glacier mass balance. Here, using 17 (>55 °N latitude) glacier and ice cap mass balance series in the 1971–2017 period, we develop a semi-empirical estimate of annual sea-level contribution from seven Arctic regions by scaling the in situ records to GRACE averages. We contend that our estimate represents the most accurate Arctic land ice mass balance assessment so far available before the 1992 start of satellite altimetry. We estimate the 1971–2017 eustatic sea-level contribution from land ice north of ~55 °N to be 23.0 ± 12.3 mm sea-level equivalent (SLE). In all regions, the cumulative sea-level rise curves exhibit an acceleration, starting especially after 1988. Greenland is the source of 46% of the Arctic sea-level rise contribution (10.6 ± 7.3 mm), followed by Alaska (5.7 ± 2.2 mm), Arctic Canada (3.2 ± 0.7 mm) and the Russian High Arctic (1.5 ± 0.4 mm). Our annual results exhibit co-variability over a 43 year overlap (1971–2013) with the alternative dataset of Marzeion et al (2015 Cryosphere 9 2399–404) (M15). However, we find a 1.36× lower sea-level contribution, in agreement with satellite gravimetry. The IPCC Fifth Assessment report identified constraining the pre-satellite era sea-level budget as a topic of low scientific understanding that we address and specify sea-level contributions coinciding with IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) 'present day' (2005–2015) and 'recent past' (1986–2005) reference periods. We assess an Arctic land ice loss of 8.3 mm SLE during the recent past and 12.4 mm SLE during the present day. The seven regional sea-level rise contribution time series of this study are available from AMAP.no.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:03 Institute of Physics (IOP) English 2018

Not carbon neutral: Assessing the net emissions impact of residues burned for bioenergy

Climate mitigation requires emissions to peak then decline within two decades, but many mitigation models include 100 EJ or more of bioenergy, ignoring emissions from biomass oxidation. Treatment of bioenergy as 'low carbon' or carbon neutral often assumes fuels are agricultural or forestry residues that will decompose and emit CO2 if not burned for energy. However, for 'low carbon' assumptions about residues to be reasonable, two conditions must be met: biomass must genuinely be material left over from some other process; and cumulative net emissions, the additional CO2 emitted by burning biomass compared to its alternative fate, must be low or negligible in a timeframe meaningful for climate mitigation. This study assesses biomass use and net emissions from the US bioenergy and wood pellet manufacturing sectors. It defines the ratio of cumulative net emissions to combustion, manufacturing and transport emissions as the net emissions impact (NEI), and evaluates the NEI at year 10 and beyond for a variety of scenarios. The analysis indicates the US industrial bioenergy sector mostly burns black liquor and has an NEI of 20% at year 10, while the NEI for plants burning forest residues ranges from 41%–95%. Wood pellets have a NEI of 55%–79% at year 10, with net CO2 emissions of 14–20 tonnes for every tonne of pellets; by year 40, the NEI is 26%–54%. Net emissions may be ten times higher at year 40 if whole trees are harvested for feedstock. Projected global pellet use would generate around 1% of world bioenergy with cumulative net emissions of 2 Gt of CO2 by 2050. Using the NEI to weight biogenic CO2 for inclusion in carbon trading programs and to qualify bioenergy for renewable energy subsidies would reduce emissions more effectively than the current assumption of carbon neutrality.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:44 Institute of Physics (IOP) English 2018

Assessing the evolution of power sector carbon intensity in the United States

In the United States, the electricity sector is a major focus for implementing policies to meet national, state, or local mandatory or voluntary CO2 emissions reductions goals. Thus, it is important to have timely and available information on greenhouse gas emissions generated by the power sector to ensure that the policies implemented achieve intended emissions reductions. This work is the first to develop a transparent method to compute the emissions intensity for the US electricity section from 2001 through 2017 at different temporal (annual, quarterly, monthly) and regional (US, NERC, and state) levels. We find that between 2001 and 2017 the average annual CO2 emissions intensity of electricity production in the United States decreased by 30%, from 630 g CO2 kWh−1 to 439 g CO2 kWh−1. This change in CO2 intensity is attributable to an increase in generation from natural gas and wind accompanied by a reduction in coal-fired power generation. The decline in carbon intensity varies across regions, with the largest reduction between 2001 and 2017 from power plants in the Northeast (58%) and the smallest reduction from power plants in the Texas region (27%). In absolute terms the South-central region saw the largest decrease in emissions intensity (358 g CO2 kWh−1) and Texas saw the smallest (164 g CO2 kWh−1). We also find that replacing coal generation with natural gas or renewables has increased the monthly correlation of CO2 intensity between regions. At the state level, Delaware saw the largest decrease in CO2 intensity (466 g CO2 kWh−1), and Idaho is the only state that has not decreased CO2 intensity since 2001.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:52 Institute of Physics (IOP) English 2018

Competition for shrinking window of low salinity groundwater

Groundwater resources are being stressed from the top down and bottom up. Declining water tables and near-surface contamination are driving groundwater users to construct deeper wells in many US aquifer systems. This has been a successful short-term mitigation measure where deep groundwater is fresh and free of contaminants. Nevertheless, vertical salinity profiles are not well-constrained at continental-scales. In many regions, oil and gas activities use pore spaces for energy production and waste disposal. Here we quantify depths that aquifer systems transition from fresh-to-brackish and where oil and gas activities are widespread in sedimentary basins across the United States. Fresh-brackish transitions occur at relatively shallow depths of just a few hundred meters, particularly in eastern US basins. We conclude that fresh groundwater is less abundant in several key US basins than previously thought; therefore drilling deeper wells to access fresh groundwater resources is not feasible extensively across the continent. Our findings illustrate that groundwater stores are being depleted not only by excessive withdrawals, but due to injection, and potentially contamination, from the oil and gas industry in areas of deep fresh and brackish groundwater.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
02:18 Institute of Physics (IOP) English 2018

Grasslands may be more reliable carbon sinks than forests in California

Although natural terrestrial ecosystems have sequestered ~25% of anthropogenic CO2 emissions, the long-term sustainability of this key ecosystem service is under question. Forests have traditionally been viewed as robust carbon (C) sinks; however, extreme heat-waves, drought and wildfire have increased tree mortality, particularly in widespread semi-arid regions, which account for ~41% of Earth's land surface. Using a set of modeling experiments, we show that California grasslands are a more resilient C sink than forests in response to 21st century changes in climate, with implications for designing climate-smart Cap and Trade offset policies. The resilience of grasslands to rising temperatures, drought and fire, coupled with the preferential banking of C to belowground sinks, helps to preserve sequestered terrestrial C and prevent it from re-entering the atmosphere. In contrast, California forests appear unable to cope with unmitigated global changes in the climate, switching from substantial C sinks to C sources by at least the mid-21st century. These results highlight the inherent risk of relying on forest C offsets in the absence of management interventions to avoid substantial fire-driven C emissions. On the other hand, since grassland environments, including tree-sparse rangelands, appear more capable of maintaining C sinks in 21st century, such ecosystems should be considered as an alternative C offset to climate-vulnerable forests. The further development of climate-smart approaches in California's carbon marketplace could serve as an example to offset programs around the world, particularly those expanding into widespread arid and semi-arid regions.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
02:02 Institute of Physics (IOP) No linguistic content; Not applicable 2018

Climate-informed environmental inflows to revive a drying lake facing meteorological and anthropogenic droughts

The rapid shrinkage of Lake Urmia, one of the world's largest saline lakes located in northwestern Iran, is a tragic wake-up call to revisit the principles of water resources management based on the socio-economic and environmental dimensions of sustainable development. The overarching goal of this paper is to set a framework for deriving dynamic, climate-informed environmental inflows for drying lakes considering both meteorological/climatic and anthropogenic conditions. We report on the compounding effects of meteorological drought and unsustainable water resource management that contributed to Lake Urmia's contemporary environmental catastrophe. Using rich datasets of hydrologic attributes, water demands and withdrawals, as well as water management infrastructure (i.e. reservoir capacity and operating policies), we provide a quantitative assessment of the basin's water resources, demonstrating that Lake Urmia reached a tipping point in the early 2000s. The lake level failed to rebound to its designated ecological threshold (1274 m above sea level) during a relatively normal hydro-period immediately after the drought of record (1998–2002). The collapse was caused by a marked overshoot of the basin's hydrologic capacity due to growing anthropogenic drought in the face of extreme climatological stressors. We offer a dynamic environmental inflow plan for different climate conditions (dry, wet and near normal), combined with three representative water withdrawal scenarios. Assuming effective implementation of the proposed 40% reduction in the current water withdrawals, the required environmental inflows range from 2900 million cubic meters per year (mcm yr−1) during dry conditions to 5400 mcm yr−1 during wet periods with the average being 4100 mcm yr−1. Finally, for different environmental inflow scenarios, we estimate the expected recovery time for re-establishing the ecological level of Lake Urmia.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: No linguistic content; Not applicable
03:15 Institute of Physics (IOP) English 2018

Implications of a shrinking Great Salt Lake for dust on snow deposition in the Wasatch Mountains, UT, as informed by a source to sink case study from the 13–14 April 2017 dust event

The deposition of dust on snow accelerates melt by perturbing snow albedo, directly by darkening the snow surface and indirectly by enhancing snow grain growth. The snow darkening process impacts hydrology by shifting runoff timing and magnitude. Dust on snow deposition has been documented in the Wasatch Mountains, snowmelt from which accounts for up to 80% of surface water supply for Salt Lake City, UT, but the impact on snow melt has not yet been investigated. Here, we present a case study of a dust event observed in the Wasatch (13–14th April, 2017), sampled coincidentally in the air and at the snow surface at an instrumented high elevation site (Atwater Study Plot, Alta, UT). Atmospheric backtrajectory modeling, the results of which were supported by measurements, showed that dust originated predominantly from the west: the Great Salt Lake Desert and the Great Salt Lake (GSL) dry lake bed. The deposited dust mass accounted for ~50% of the season total dust loading in snow, and daily mean radiative forcing of 20–50 W m−2 accelerated snow melt by approximately 25%. This has important implications for The Greatest Snow on Earth®, and snow water resources; the water level of the GSL has been declining, exposing dry lake beds, and there are no legal water rights or protections to maintain lake levels or mitigate dust emission.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:24 Institute of Physics (IOP) English 2018

Global impacts of the meat trade on in-stream organic river pollution: the importance of spatially distributed hydrological conditions

In many regions of the world, intensive livestock farming has become a significant source of organic river pollution. As the international meat trade is growing rapidly, the environmental impacts of meat production within one country can occur either domestically or internationally. The goal of this paper is to quantify the impacts of the international meat trade on global organic river pollution at multiple scales (national, regional and gridded). Using the biological oxygen demand (BOD) as an overall indicator of organic river pollution, we compute the spatially distributed organic pollution in global river networks with and without a meat trade, where the without-trade scenario assumes that meat imports are replaced by local production. Our analysis reveals a reduction in the livestock population and production of organic pollutants at the global scale as a result of the international meat trade. However, the actual environmental impact of trade, as quantified by in-stream BOD concentrations, is negative; i.e. we find a slight increase in polluted river segments. More importantly, our results show large spatial variability in local (grid-scale) impacts that do not correlate with local changes in BOD loading, which illustrates: (1) the significance of accounting for the spatial heterogeneity of hydrological processes along river networks, and (2) the limited value of looking at country-level or global averages when estimating the actual impacts of trade on the environment.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:42 Institute of Physics (IOP) English 2018

The Guiana Shield rainforests—overlooked guardians of South American climate

Tropical forests are global climate regulators through their interaction with hydrological and biogeochemical cycles. Despite extensive research on deforestation in South America and its global impact, the role of the largely intact Guiana Shield forests, north of the Amazon, has not yet been considered as part of this climate system. We use a regional climate model with a realistic deforestation scenario to test the impact of deforestation in the Guiana Shield on climate throughout South America. We show that replacing ~28% of the current Guiana Shield rainforest with savannah leads to multi-scale impacts across South America, through vegetation-land-atmosphere interactions that disrupt the initial phase of two major 'atmospheric rivers': the Caribbean low-level Jet and the South American low-level jet (SALLJ). Our climate simulations suggest that following deforestation, locally, precipitation and runoff would more than double in lowland forests, whilst mean annual temperatures would increase by up to 2.2 °C in savannahs. Regionally, significant wetting is simulated in northern South America (April−September) and the western Amazon (October–March), while temperatures increase up to 2 °C in central and eastern Amazon, causing more dry months in up to 64% of the Amazon basin. Reduction of moisture transfer by the SALLJ of 2.2% of total annual flow causes noticeable and highly diverse spatial changes in simulated monthly rainfall in la plata basin (LPB). These results highlight the potential consequences of land cover change in a sensitive hot-spot with hydro-climatic impacts 1000 km west and 4000 km south. Such multi-scale perturbations can severely impact biodiversity and ecosystem services across South America, including agriculture in LPB. Recognition of the far field effects of localised deforestation in key areas is urgently needed to improve development plans for a sustainable future.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
02:26 Institute of Physics (IOP) English 2018

Committed emissions from existing and planned power plants and asset stranding required to meet the Paris Agreement

Over the coming decade, the power sector is expected to invest ~7.2 trillion USD in power plants and grids globally, much of it into CO2-emitting coal and gas plants. These assets typically have long lifetimes and commit large amounts of (future) CO2 emissions. Here, we analyze the historic development of emission commitments from power plants and compare the emissions committed by current and planned plants with remaining carbon budgets. Based on this comparison we derive the likely amount of stranded assets that would be required to meet the 1.5 °C–2 °C global warming goal. We find that even though the growth of emission commitments has slowed down in recent years, currently operating generators still commit us to emissions (~300 GtCO2) above the levels compatible with the average 1.5 °C–2 °C scenario (~240 GtCO2). Furthermore, the current pipeline of power plants would add almost the same amount of additional commitments (~270 GtCO2). Even if the entire pipeline was cancelled, therefore, ~20% of global capacity would need to be stranded to meet the climate goals set out in the Paris Agreement. Our results can help companies and investors re-assess their investments in fossil-fuel power plants, and policymakers strengthen their policies to avoid further carbon lock-in.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
03:19 Institute of Physics (IOP) English 2018

Implications of a decrease in the precipitation area for the past and the future

The total area with 24 hrs precipitation has shrunk by 7% between 50°S–50°N over the period 1998–2016, according to the satellite-based Tropical Rain Measurement Mission data. A decrease in the daily precipitation area is an indication of profound changes in the hydrological cycle, where the global rate of precipitation is balanced by the global rate of evaporation. This decrease was accompanied by increases in total precipitation, evaporation, and wet-day mean precipitation. If these trends are real, then they suggest increased drought frequencies and more intense rainfall. Satellite records, however, may be inhomogeneous because they are synthesised from a number of individual missions with improved technology over time. A linear dependency was also found between the global mean temperature and the 50°S–50°N daily precipitation area with a slope value of −17 × 106 km 2∕°C. This dependency was used with climate model simulations to make future projections which suggested a continued decrease that will strengthen in the future. The precipitation area evolves differently when the precipitation is accumulated over short and long time scales, however, and there has been a slight increase in the monthly precipitation area while the daily precipitation area decreased. An increase on monthly scale may indicate more pronounced variations in the rainfall patterns due to migrating rain-producing phenomena.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
04:05 Institute of Physics (IOP) English 2018

Global exposure and vulnerability to multi-sector development and climate change hotspots

Understanding the interplay between multiple climate change risks and socioeconomic development is increasingly required to inform effective actions to manage these risks and pursue sustainable development. We calculate a set of 14 impact indicators at different levels of global mean temperature (GMT) change and socioeconomic development covering water, energy and land sectors from an ensemble of global climate, integrated assessment and impact models. The analysis includes changes in drought intensity and water stress index, cooling demand change and heat event exposure, habitat degradation and crop yield, amongst others. To investigate exposure to multi-sector climate impacts, these are combined with gridded socioeconomic projections of population and those 'vulnerable to poverty' from three Shared Socioeconomic Pathways (SSP) (income <10/day, currently 4.2 billion people). We show that global exposure to multi-sector risks approximately doubles between 1.5 °C and 2 °C GMT change, doubles again with 3 °C GMT change and is ~6x between the best and worst cases (SSP1/1.5 °C vs SSP3/3 °C, 0.8–4.7bi). For populations vulnerable to poverty, the exposure is an order of magnitude greater (8–32x) in the high poverty and inequality scenarios (SSP3) compared to sustainable socioeconomic development (SSP1). Whilst 85%–95% of global exposure falls to Asian and African regions, they have 91%–98% of the exposed and vulnerable population (depending on SSP/GMT combination), approximately half of which in South Asia. In higher warming scenarios, African regions have growing proportion of the global exposed and vulnerable population, ranging from 7%–17% at 1.5 °C, doubling to 14%–30% at 2 °C and again to 27%–51% at 3 °C. Finally, beyond 2 °C and at higher risk thresholds, the world's poorest are disproportionately impacted, particularly in cases (SSP3) of high inequality in Africa and southern Asia. Sustainable development that reduces poverty, mitigates emissions and meets targets in the water, energy and land sectors has the potential for order-of-magnitude scale reductions in multi-sector climate risk for the most vulnerable.
  • Published: 2018
  • Publisher: Institute of Physics (IOP)
  • Language: English
49:11 Bibcast German 2017

Mobile Makerspaces in kleineren Bibliotheken: Bericht zu einem Forschungsprojekt

Makerspaces haben sich als Thema in der bibliothekarischen Literatur etabliert, in vielen Fällen haben Bibliotheken solche inden letzten Jahren aufgebaut oder betreffende Veranstaltungen durchgeführt. Es scheint, dass es Zeit ist, über die reine Frage, ob sie für Bibliotheken möglich wären (das sind sie) hinauszugehen. Während viele Makerspaces in grösseren Bibliotheken eingerichtet wurde, untersuchte ein Projekt an der HTW Chur, ob und wie sich Makerspaces für kleine und kleinste (schweizerische) Bibliotheken umsetzen lassen. Hierbei ging es vor allem darum, funktionierende Techniken zufinden, die sich in den Arbeitsalltag der Kolleginnen und Kollegen in kleinen Bibliotheken, die wenig Zeit zum „Lernen“ von Technik für Makerspaces und wenig Ressourcen für den Kauf dieser Techniken aufbringen können, integrieren lassen. Das Projekt wurde Ende 2016 in vier schweizerischen Gemeindebibliotheken durchgeführt. Es zeigte sich, dass die Idee, was ein Makerspace ist und können soll, in den Bibliotheken unterschiedlich interpretiert wird und am Ende wenig mit dem, was in der Literatur vorhergesagt wird, zu tun hat; aber auch, das grundsätzlich in kleinen Bibliotheken Veranstaltungen dieser Art durchgeführt werden können, wenn diese Zugang zu den betreffenden Technologien haben. Prägend für die Veranstaltungen war immer der lokale Rahmen, gleichzeitig liessen sich Gemeinsamkeiten beobachten. Makerspaces werden z.B. nicht als feste, sondern als temporäre Angebote gut geheissen; es geht eher um kurzfristige interessante Veranstaltungen als um direkte langfristige Wirkungen. Die Potentiale der Technologien werden nur z.T. genutzt. Im Vortrag werden die Ergebnisse des Projektes berichtet und sowohl in die Beiträge zu Makerspaces in Bibliotheken eingeordnet als auch die mögliche Umsetzung in anderen Bibliotheken diskutiert.
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
46:41 Bibcast German 2017

Ein umfassendes Verzeichnis deutscher Informationseinrichtungen

Ein umfassendes Verzeichnis von Bibliotheken und verwandten Einrichtungen in Deutschland - das hat es bisher nicht gegeben. Zwar existieren zwei umfangreiche Verzeichnisse bibliothekarischer Einrichtungen: das Sigelverzeichnis mit Fokus auf den Bereich "Wissenschaftliche Bibliotheken" und die Deutsche Bibliotheksstatistik (DBS), deren Stammdatenbank hauptsächlich Beschreibungen Öffentlicher Bibliotheken umfasst. Es war bisher aber nicht möglich, beide Verzeichnisse gemeinsam abzufragen. Das Hochschulbibliothekszentrum des Landes Nordrhein-Westfalen (hbz) hat durch eine Zusammenführung beider Verzeichnisse ein umfassendes Organisationsverzeichnis hergestellt und im Web verfügbar gemacht. Seit 2010 bietet das hbz mit dem Dienst "lobid" verschiedene bibliothekarisch relevante Informationen als Linked Data an. Mitte 2014 begann das lobid-Team damit, durch die Integration der Stammdaten der Deutschen Bibliotheksstatistik (DBS) ein umfassendes Verzeichnis deutscher Bibliotheken bereitszustellen. Der Vortrag stellt das Ergebnis vor: http://lobid.org/organisations, eine webbasierte Programmierschnittstelle mit intuitiver Benutzeroberfläche. Die lobid-organisations-API leistet einen nützlichen Beitrag für die deutschlandweite Informationsinfrastruktur, indem sie strukturierte Beschreibungen von knapp 30.000 Organisationen bereitstellt und vielfältige Datenabfragen ermöglicht. Beispiele für Anwendungen, die auf der API aufsetzen (können), sind etwa einfache Statistiken, die u. a. eine Antwort auf folgende Fragen bieten: Wie viele Bibliotheken eines bestimmten Typs gibt es in Deutschland oder in einem bestimmten Bundesland oder Landkreis? Aufsetzend auf der API bietet das hbz eine Rechercheoberfläche an, die zum Entdecken von Informationseinrichtungen in Deutschland einlädt. Filterung von Suchergebnissen nach Standort ist über eine Kartenansicht möglich, mit verschiedenen weiteren Facetten lässt sich nach Bibliothekstyp oder Unterhaltsträger filtern.
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
1:02:44 Bibcast German 2017

FWB-Online - Die Erschließung eines Wörterbuchschatzes

Die Akademie der Wissenschaften zu Göttingen (AdWG) ist eine traditionsreiche Gelehrtengesellschaft und eine außeruniversitäre Forschungseinrichtung. Als Forschungseinrichtung betreut sie in einer schnelllebigen Zeit wissenschaftliche Langzeitprojekte. Die niedersächsische Staats- und Universitätsbibliothek Göttingen (SUB) ist eine der größten wissenschaftlichen Bibliotheken in Deutschland und führend in der Forschung und Entwicklung von Forschungsinfrastrukturen im Bereich eResearch. Die AdWG und die SUB haben ihre Kooperation intensiviert und bieten gemeinsam eine Digitale Bibliothek für die AdWG an. Im Rahmen dieser Kooperation wird eine Online-Version des Frühneuhochdeutschen Wörterbuchs (FWB) FWB-online umgesetzt. Das FWB beschreibt den Wortschatz der hochdeutschen Sprache von etwa 1350 bis 1650. Für FWB-online wurden die typographisch ausgezeichneten Satzdaten der Buchproduktion in ein semantisch tiefstrukturiertes TEI-XML transformiert. Über einen Suchindex wird es den Nutzern ermöglicht, Abfragen zu formulieren, die das FWB in einem völlig neuen Ausmaß erschließen. FWB-online bietet die Wahl zwischen einer Standardsuche, die alle Teile der Artikel einbezieht und einer erweiterten Suche, welche die Tiefenstruktur des Wörterbuchs gezielt abfragen kann. So kann der Nutzende beispielsweise eine exakte Suche, eine unscharfe Suche, die Suche nach exotischen Unicode-Zeichen oder eine Suche nur in frühneuhochdeutschen Zitaten anstoßen. Bei der Softwareentwicklung wurden aktuelle Entwicklungsmethoden und ein agiles Projektmanagement eingesetzt, um die Anforderungen der Nutzenden an den Dienst als auch an die Usability zu gewährleisten. Die Entwicklung erfolgt mit Scrum: In kurzen Iterationsschritten werden jeweils Zwischenergebnisse klar definiert und vorgestellt. Der Vortrag geht neben der technischen Umsetzung eines solchen Projektes vor allem auf die inhaltlichen Funktionen des FWB-online ein und gibt einen Einblick in die vielfältigen Funktionen des Wörterbuchs.
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
1:03:20 Bibcast German 2017

Offene Lernskripte mit Gitbook - Erfahrungsbericht aus einem Seminar

Viele Skripte zu Seminaren und Vorlesungen liegen versteckt in Lernplattformen, die genauso gut frei im Netz veröffentlicht werden könnten. Dann wären Sie auch für Selbstlernende und als Vorlage für andere Lehrende zugänglich. Der Aufwand für die Erstellung von Open Educational Resources schreckt aber wohl viele ab. Abhilfe versprechen aktuelle Publikationswerkzeuge wie die kostenfreie Software Gitbook. Im Seminar „Wir bauen uns einen Bibliothekskatalog“ im Studiengang Bibliotheks- und Informationsmanagement der HAW Hamburg haben wir Erfahrungen mit der Software Gitbook gesammelt. Das Skript [1] steht als HTML mit Suchfunktion sowie als PDF und ePub zur Verfügung und kann vom Dozenten schnell und leicht editiert werden. Andere Lehrende können es über Github kopieren und anpassen. Im Vortrag erwarten Sie eine Live-Demo der Software, ein Erfahrungsbericht und Empfehlungen zur Nachnutzung. Außerdem werden die offenen Lerntagebücher [2] der Studierenden vorgestellt, die sie mit WordPress angelegt haben. [1] https://www.gitbook.com/read/book/felixlohmeier/seminar-wir-bauen-uns-einen-bibliothekskatalog [2] https://felixlohmeier.gitbooks.io/seminar-wir-bauen-uns-einen-bibliothekskatalog/content/lerntagebucher.html
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
52:00 Bibcast German 2017

Einführung zum NMC Horizon Report 2017 Library Edition

Einführungsvortrag zum NMC Horizon Report 2017 Library Edition. Der Vortrag dient der Vorbereitung auf das Hands-On-Lab „Ausblick auf Bibliotheken im Jahr 2027: Keytrends aus dem NMC Horizon Report 2017 Library Edition weiter gedacht" auf dem Bibliothekartag 2017.
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
37:20 Bibcast German 2017

Open Library of Humanities- Konsortiale Förderung von Open Access in den Geisteswissenschaften

Der Vortrag stellt die Open Library of Humanities (OLH) vor, ein alternatives, qualitativ hochwertiges und nachhaltiges Publikationsmodell für Open Access in den Geisteswissenschaften. Das Modell stellt im Open-Access-Umfeld, in dem in den letzten Jahren APC-Modelle die Diskussion dominieren, von denen insbesondere die Großverlage profitieren, einen echten Lichtblick dar. Die OLH ist eine gemeinnützige und von Wissenschaftler/innen gegründete Plattform für Open-Access-Zeitschriften im Bereich der Geisteswissenschaften und betreibt ein gleichnamiges Megajournal. Die OLH verzichtet auf die Zahlungvon Autorengebühren (APC´s) und finanziert sich über Konsortialzahlungen von Bibliotheken sowie die Andrew W. Mellon Stiftung. Über 200 Bibliotheken unterstützen das Modell bereits. Zum jetzigen Zeitpunkt werden 18 Open-Access-Journale betrieben und die Bewerberliste der interessierten Zeitschriften ist lang. Ein zentraler Aspekt der OLH ist, dass hier bestehende Subskriptionsjournale in Open-Access-Zeitschriften umgewandelt werden. Ein sehr erfolgreiches Beispiel ist die Elsevier-Zeitschrift Lingua deren gesamtes Editorial Board zurückgetreten und mit Unterstützung der OLH die Open-Access-Zeitschrift Glossa gegründet hat. In den nächsten Jahren soll eine Ausweitung der OLH auf andere Disziplinen erfolgen. Nach dem sehr erfolgreichen Start der englischsprachigen Plattform, gibt es nun auch eine deutsch- und französischsprachige Oberfläche sowie deutsch- und französischsprachige Editorenteams. Während das Modell insbesondere im anglo-amerikanischen Raum viel Zuspruch findet, beteiligen sich bislang nur wenige deutschsprachige Bibliotheken. Für Österreich hat die dortige Förderorganisation FWF ihre Unterstützung für die OLH im Namen aller Bibliotheken für fünf Jahre zugesichert. Die Universität Konstanz ist seit August 2016 Mitglied im Partnerprogramm für Bibliotheken und unterstützt die OLH neben dem Aufbau der deutschsprachigen Oberfläche der Plattform dabei, weitere Unterstützer im deutschsprachigen Raumzu gewinnen. Je nach Größe zahlen Bibliotheken zwischen 800 und 2000 Euro im Jahr für eine Mitgliedschaft.
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
54:55 Bibcast German 2017

E-Books - Versprechen vs. Realität

Wo stehen wir in Bezug auf E-Books allgemein und spezifisch in Bibliotheken im deutschen Sprachraum? Angekündigt war vor ein paar Jahren die baldige Ablösung von Büchern durch ihre elektronische Version. Doch stellt man neuerdings fest, dass auch die Verkaufszahlen von E-Books tendenziell wieder rückläufig sind, jedenfalls im Publikumsmarkt. Im Vortrag wird aufgezeigt, was E-Books im Prinzip leisten könnten und was sie heute nur in sehr beschränktem Mass tun. Es werden die aktuellen Konzepte, Formate und Geschäftsmodelle von Verlagen, Aggregatoren, Bibliotheken unter die Lupe genommen. Es wird weiter gezeigt, wie sich die Situation in Öffentlichen und Wissenschaftlichen Bibliotheken gestaltet. Insbesondere soll dargestellt werden, inwiefern sich die Wünsche und Erwartungen der Nutzerinnen und Nutzer in den aktuellen Angeboten wiederfinden – oder eben nicht.
  • Published: 2017
  • Publisher: Bibcast
  • Language: German
04:01 Institute of Physics (IOP) English 2017

General framework for fluctuating dynamic density functional theory

We introduce a versatile bottom-up derivation of a formal theoretical framework to describe (passive) soft-matter systems out of equilibrium subject to fluctuations. We provide a unique connection between the constituent-particle dynamics of real systems and the time evolution equation of their measurable (coarse-grained) quantities, such as local density and velocity. The starting point is the full Hamiltonian description of a system of colloidal particles immersed in a fluid of identical bath particles. Then, we average out the bath via Zwanzig's projection-operator techniques and obtain the stochastic Langevin equations governing the colloidal-particle dynamics. Introducing the appropriate definition of the local number and momentum density fields yields a generalisation of the Dean–Kawasaki (DK) model, which resembles the stochastic Navier–Stokes description of a fluid. Nevertheless, the DK equation still contains all the microscopic information and, for that reason, does not represent the dynamical law of observable quantities. We address this controversial feature of the DK description by carrying out a nonequilibrium ensemble average. Adopting a natural decomposition into local-equilibrium and nonequilibrium contribution, where the former is related to a generalised version of the canonical distribution, we finally obtain the fluctuating-hydrodynamic equation governing the time-evolution of the mesoscopic density and momentum fields. Along the way, we outline the connection between the ad hoc energy functional introduced in previous DK derivations and the free-energy functional from classical density-functional theory. The resultant equation has the structure of a dynamical density-functional theory (DDFT) with an additional fluctuating force coming from the random interactions with the bath. We show that our fluctuating DDFT formalism corresponds to a particular version of the fluctuating Navier–Stokes equations, originally derived by Landau and Lifshitz. Our framework thus provides the formal apparatus for ab initio derivations of fluctuating DDFT equations capable of describing the dynamics of soft-matter systems in and out of equilibrium.
  • Published: 2017
  • Publisher: Institute of Physics (IOP)
  • Language: English
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