ALBERT

Description: Detrital provenance analyses in orogenic settings, in which sediments are collected at the outlet of a catchment, have become an important tool to es-timate how erosion varies in space and time. Here we present how Raman Spectroscopy on Carbonaceous Material (RSCM) can be used for provenance analysis. RSCM provides an estimate of the peak temperature (RSCM-T) experienced during metamorphism. We show that we can infer modern ero-sion patterns in a catchment by combining new measurements on detrital sands with previously acquired bedrock data. We focus on the Whataroa catch-ment in the Southern Alps of New Zealand and exploit the metamorphic gra-dient that runs parallel to the main drainage direction. To account for po-tential sampling biases, we also quantify abrasion properties using flume ex-periments and measure the total organic carbon content in the bedrock that produced the collected sands. Finally, we integrate these parameters into a mass-conservative model. Our results fist demonstrate that RSCM-T can be used for detrital studies. Second, we finnd that spatial variations in tracer concentration and erosion have a rst-order control on the RSCM-T distri-butions, even though our flume experiments reveal that weak lithologies pro-duce substantially more ne particles than do more durable lithologies. This result implies that sand specimens are good proxies for mapping spatial vari-ations in erosion when the bedrock concentration of the target mineral is quan-tied. The modeling suggests highest present-day erosion rates (in Whataroa catchment) are not situated at the range front, but around 10 km into the mountain belt.

Description: Europe experienced a pronounced winter cooling of about –0.37 °C/decade in the period 1989-2012, in contrast to the strong warming simulated by the CMIP5 multi-model average during the same period. Even more pronounced discrepancies between observed and simulated short-term trends are found at the local scale, e.g. , a strong winter cooling over Switzerland and a pronounced reduction in precipitation along the coast of Norway. We show that monthly sea level pressure variability accounts for much of the short-term variations of temperature over most of the domain and of precipitation in certain regions. Removing the effect of atmospheric circulation through a regression approach reconciles the observed temperature trends over Europe and Switzerland and the precipitation trend along the coast of Norway with the corresponding multi-model mean trends.

Description: [1]  The Madden–Julian oscillation (MJO) is the dominant mode of intraseasonal variability in tropical rainfall on the large scale, but its signal is often obscured in individual station data, where effects are most directly felt at the local level. The Fly River system, Papua New Guinea, is one of the wettest regions on Earth and is at the heart of the MJO envelope. 16-year time series of daily precipitation at 15 stations along the river system exhibit strong MJO modulation in rainfall. At each station, the difference in rainfall rate between active and suppressed MJO conditions is typically 40% of the station mean. The spread of rainfall between individual MJO events was small enough such that the rainfall distributions between wet and dry phases of the MJO were clearly separated, at the catchment level. This implies that successful prediction of the large-scale MJO envelope will have a practical use for forecasting local rainfall. In the steep topography of the New Guinea Highlands, the mean and MJO signal in station precipitation is twice that in the satellite TRMM 3B42HQ product, emphasising the need for ground truthing satellite-based precipitation measurements. A clear MJO signal is also present in the river level, which peaks simultaneously with MJO precipitation input in its upper reaches, but lags the precipitation by approximately 18 days on the flood plains.

Description: Most herbivorous insect species are restricted to a narrow taxonomic range of host plant species. Herbivore species that feed on mustard plants and their relatives in the Brassicales have evolved highly efficient detoxification mechanisms that actually prevent toxic mustard oils from forming in the bodies of the animals. However, these mechanisms likely were not present during the initial stages of specialization on mustard plants ~100 million years ago. The herbivorous fly Scaptomyza nigrita (Drosophilidae) is a specialist on a single mustard species, bittercress ( Cardamine cordifolia ; Brassicaceae) and is in a fly lineage that evolved to feed on mustards only in the past 10–20 million years. In contrast to many mustard specialists, S. nigrita does not prevent formation of toxic breakdown products (mustard oils) arising from glucosinolates (GLS), the primary defensive compounds in mustard plants. Therefore, it is an appealing model for dissecting the early stages of host specialization. Because mustard oils actually form in the bodies of S. nigrita, we hypothesized that in lieu of a specialized detoxification mechanism, S. nigrita may mitigate exposure to high GLS levels within plant tissues using behavioral avoidance. Here, we report that jasmonic acid (JA) treatment increased GLS biosynthesis in bittercress, repelled adult female flies, and reduced larval growth. S. nigrita larval damage also induced foliar GLS, especially in apical leaves, which correspondingly displayed the least S. nigrita damage in controlled feeding trials and field surveys. Paradoxically, flies preferred to feed and oviposit on GLS-producing Arabidopsis thaliana despite larvae performing worse in these plants versus non-GLS-producing mutants. GLS may be feeding cues for S. nigrita despite their deterrent and defensive properties, which underscores the diverse relationship a mustard specialist has with its host when lacking a specialized means of mustard oil detoxification. Many specialists herbivores can subvert host plant defensive chemistry, allowing them to “feed with impunity” on plant tissues. But despite being a specialist herbivore, Scaptomyza nigrita lacks a specialized means of overcoming the toxic mustard oils of its Brassicacea host. Here, we show that this herbivore exhibits a behavioral strategy for mitigating host plant toxicity by avoiding high concentrations of mustard oil precursors where possible, even though these compounds themselves may be important for initiating host feeding.

Description: Potentially active faults are exposed in the steep glaciated topography of the central Southern Alps, New Zealand, immediately adjacent to the Alpine Fault plate boundary. Four major faults exposed along the flanks of three of the highest mountain ranges strike 10–23 km (potentially 40 km) NNE oblique to the Alpine Fault, dipping 57° ± 12° NW in the opposite direction. Youngest discernable motions were reverse dip-slip, accommodating both margin-perpendicular shortening and dextral margin-parallel components of plate motion. Kinematic analysis yields a compression axis (295/10° ± 9° trend or plunge) equivalent to the contemporary shortening determined from seismological and geodetic studies, suggesting the faults may be active, although definitive evidence for recent movement or single event displacements is lacking. There are 106 other potentially active faults mapped in central Southern Alps with strike lengths 4–73 km. Earthquake parameters were assigned from fault trace lengths and historical earthquake statistics, indicating potential for MW 5.5–7.4 earthquakes at recurrence intervals of 1000–10,000 years. Such long recurrence intervals are consistent with the faults having little surface expression, with rapid erosion of these seismically agitated mountains erasing any evidence of surface rupture during periods between earthquakes. The central Southern Alps faults exemplify the difficulty in fully deciphering long-term (e.g., Holocene or Quaternary) records of seismicity in tectonically active regions with rapidly evolving landscapes. Although there may be little evidence of surface ruptures remaining in the landscape, the faults are still an important potential source of earthquakes and seismic hazard.

Description: We present a climate analysis of nine unique Swiss Alpine new snow series that have been newly digitized. The stations cover different altitudes (450–1860 m asl) and all time series cover more than 100 years (one from 1864 to 2009). In addition, data from 71 stations for the last 50–80 years for new snow and snow depth are analysed to get a more complete picture of the Swiss Alpine snow variability. Important snow climate indicators such as new snow sums (NSS), maximum new snow (MAXNS) and days with snowfall (DWSF) are calculated and variability and trends analysed. Series of days with snow pack (DWSP) ≥ 1 cm are reconstructed with useful quality for six stations using the daily new snow, local temperature and precipitation data. Our results reveal large decadal variability with phases of low and high values for NSS, DWSF and DWSP. For most stations NSS, DWSF and DWSP show the lowest values recorded and unprecedented negative trends in the late 1980s and 1990s. For MAXNS, however, no clear trends and smaller decadal variability are found but very large MAXNS values (〉60 cm) are missing since the year 2000. The fraction of NSS and DWSP in different seasons (autumn, winter and spring) has changed only slightly over the ∼150 year record. Some decreases most likely attributable to temperature changes in the last 50 years are found for spring, especially for NSS at low stations. Both the NSS and DWSP snow indicators show a trend reversal in most recent years (since 2000), especially at low and medium altitudes. This is consistent with the recent ‘plateauing’ (i.e. slight relative decrease) of mean winter temperature in Switzerland and illustrates how important decadal variability is in understanding the trends in key snow indicators. Copyright © 2012 Royal Meteorological Society

Description: ABSTRACT Quantifying precipitation variability and trends is difficult and merits regular reassessment. In the present study, the seasonal homogenized precipitation series in Switzerland is investigated for the period 1901–2013 in terms of trends, inter-annual variability and the influence of large-scale flow. An objective clustering is applied, resulting in 32 distinct precipitation regions. Trends are analysed for all 32 regions with moving trend windows, and statistical significance ( p  〈 0.05) is assessed with Theil–Sen trend estimates and nonparametric Mann–Kendall trend tests. Inter-annual precipitation varies considerably regionally and seasonally. Of 2720 analysed trend windows of 33–113 years in length, 194 (7.1%) show a significantly positive trend and 10 (0.4%) a significantly negative trend. Most of the significantly positive trends are found for 50+ year series for winter, autumn and the year. 81% of the annual and 72% of the winter series show positive trends (0–3% per decade) for the 1901–2013 period. The trends are significant for 34% (22%) of the annual (winter) series. Long-term trends are generally in line with earlier estimates in literature considering somewhat shorter time periods. Significantly negative trends are only found for winter in the most recent decades. No significant trends are found for inter-annual variability and changes in the 10th and 90th percentile seasonal extreme precipitation thresholds. The influence of large-scale flow on precipitation variability is strongest in winter. The leading pattern for northern Switzerland (nS) is the Euro-Atlantic blocking pattern. For southern Switzerland (sS), the Eastern Atlantic (Scandinavian) pattern is dominant in winter (autumn). In nS, wet (dry) seasons are linked to south-westerly (north-easterly) flow. In sS, wet (dry) seasons are linked to southerly (northerly) flow. Strong evidence for imprints of atmospheric blocking on seasonal precipitation variability is found in winter and autumn. In spring, a high pressure anomaly stretching from the mid-Atlantic to central Europe is indicative of dryness in nS.

Description: Simulations using density functional theory were carried out to investigate the defect properties of zirconium diboride (ZrB 2 ) and also the solution and diffusion of He and Li. Schottky and Frenkel intrinsic defect processes were all high energy as were mechanisms giving rise to nonstoichiometry; this has implications for high-temperature performance. Li and He species, formed by the transmutation of a 10 B, should therefore mostly be accommodated at the resulting vacant B sites or interstitial sites. Because Li is considerably more stable at the vacant B sites, He will be accommodated interstitially. Furthermore, He was found to diffuse as an interstitial species through the lattice with a low activation energy. This would be consistent with He being lost from the ZrB 2 but with Li being retained to a much greater extent.

Description: Abstract Eelgrass (Zostera marina) coverage and height were evaluated in 16 estuaries in the Southern Gulf of St. Lawrence, Canada, using boat‐based sonar surveys to determine the dominant factors in the decline of eelgrass in the region. Eelgrass coverage was modeled from the sonar surveys and quantified as the percentage of available habitat occupied—with habitat being defined by salinity limits (〉 10 PSU) and depth (〈 3 m). Estuaries showed a marked variation in eelgrass coverage ranging between 6% and 57% of available habitat, with eelgrass absent in the upper estuary of estuaries with the highest nitrate loading. The Dunk River estuary showed a decline in eelgrass coverage between 1967 and 2014, a period of increasing nitrogen loading. Measures of eelgrass height were not related to coverage endpoints, suggesting that height variables are not suitable endpoints for overall eelgrass health. Analysis of the influence of environmental factors showed that the factor that consistently correlated to eelgrass coverage was nitrate‐N loading while the factor most influencing eelgrass height was light attenuation. A nonlinear logistic loading‐effect model relating eelgrass coverage to nitrate‐N loading indicated that 10%, 25%, 50%, 75%, and 90% decline in eelgrass would be expected to occur in response to estuarine nitrate‐N loads of 1.3 kg ha−1 yr−1, 8.0 kg ha−1 yr−1, 50.0 kg ha−1 yr−1, 312 kg ha−1 yr−1, and 1947 kg ha−1 yr−1, respectively. These results suggest that inorganic nitrogen loading is the most significant factor to be addressed by environmental managers when addressing eelgrass declines in estuaries similar to those studied.

Description: Abstract New contingency policy plans are expected to be published by the United Kingdom government to set out urgent actions, such as carbon capture and storage, greenhouse gas removal, and the use of sustainable bioenergy to meet the greenhouse gas reduction targets of the 4th and 5th carbon budgets. In this study, we identify two plausible bioenergy production pathways for bioenergy with carbon capture and storage (BECCS) based on centralized and distributed energy systems to show what BECCS could look like if deployed by 2050 in Great Britain. The extent of agricultural land available to sustainably produce biomass feedstock in the centralized and distributed energy systems is about 0.39 and 0.5 Mha, providing approximately 5.7 and 7.3 MtDM yr−1 of biomass, respectively. If this land‐use change occurred, bioenergy crops would contribute to reduced agricultural soil GHG emission by 9 and 11 MtCO2eq yr−1 in the centralized and distributed energy systems, respectively. In addition, bioenergy crops can contribute to reduce agricultural soil ammonia emissions, water pollution from soil nitrate leaching, and to increase soil organic carbon stocks. The technical mitigation potentials from BECCS lead to projected CO2 reductions of approximately 18 and 23 MtCO2 yr−1 from the centralized and distributed energy systems, respectively. This suggests that the domestic supply of sustainable biomass would not allow the emission reduction target of 50 MtCO2 yr−1 from BECCS to be met. To meet that target, it would be necessary to produce solid biomass from forest systems on 0.59 or 0.49 Mha, or alternatively to import 8 or 6.6 MtDM yr−1 of biomass for the centralized and distributed energy system, respectively. The spatially explicit results of this study can serve to identify the regional differences in the potential capture of CO2 from BECCS, providing the basis for the development of onshore CO2 transport infrastructures. This article is protected by copyright. All rights reserved.