Top PDF A three-pillar approach to assessing climate impacts on low flows

A three-pillar approach to assessing climate impacts on low flows

A three-pillar approach to assessing climate impacts on low flows

Four runs from the regional climate model COSMO in CLi- mate Mode (COSMO-CLM) provided by the reclip:century1 project (Loibl et al., 2011) were used. The runs had been ob- tained from ECHAM5 and HADCM3 GCMs forced by three IPCC emission scenarios (A1B, B1 and A2). These scenarios were selected for consistency with other ongoing studies in Austria (e.g. Parajka et al., 2016). In order to check their real- ism with respect to droughts and low flows, the Standardized Precipitation Evaporation Index (SPEI; Vicente-Serrano et al., 2010) was evaluated, which is the Gaussian-transformed standardised monthly difference of precipitation and evap- oration. Values below zero indicate deficits in the climatic water balance, and values below −1 indicate drought condi- tions. The SPEI has been adopted here for its simplicity and because it can be calculated from the HISTALP data (Auer et al., 2007) back to the year 1800. Haslinger et al. (2014) demonstrated that the SPEI is correlated well with summer low flows in the study region. In the winter (Fig. 1, bottom panels), the simulations (light red lines) for Hoalp and Muhlv seem to be more consistent with decadal observed fluctua- tions from the HISTALP data set (red lines) than for Gurk and Buwe. Note that the comparison should focus on the long-term (decadal) dynamics rather than individual years due to the nature of the climate simulations. Overall, SPEI remains rather stable, which is due to little change in winter precipitation. In the summer (Fig. 1, top panels), the simula- tions are somewhat less consistent with the observations than for the winter, in particular for Buwe where the simulations show a decreasing trend in the overlapping period (1961– 2003), while the observations show little change. Overall, the summer SPEI projections show a decreasing trend indicating a dryer future and the trend tends to steepen beyond 2050. This is mainly due to the precipitation characteristics of the ECHAM5 simulations used and not reflected in the other models or ECHAM5 runs. The extremely negative trends in the summer SPEI should therefore be treated with caution.
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A three-pillar approach to assessing climate impacts on low flows

A three-pillar approach to assessing climate impacts on low flows

and melt have a dominant effect on the hydrologic regime, as they affect the timing of low flow periods in winter and flood events in summer. In contrast, the lowest model ef- ficiency is found for Buwe. The shape of most hydrographs is very flashy and thus very difficult to model on a daily time step. Additionally, there are only two climate stations in the catchments, which makes it difficult to capture local precipitation events such

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Assessing the biodiversity impacts of policies related to REDD+

Assessing the biodiversity impacts of policies related to REDD+

circumstances. These can range from implementing new laws and regulations and increasing the enforcement of existing ones (command and control measures) to providing payments for ecosystem services preservation (incentive based measures). The most effective measure depends on the national context. For example, where the main drivers of deforestation and forest degradation are subsistence agriculture and fuelwood collection approaches could include supporting alternative livelihoods or provision of fuel efficient stoves. In assessing the biodiversity impacts of REDD+ policies it is important to consider what REDD+ policies are likely to be implemented in that country. For example, Brazil, as outlined in section 2.1, has already had significant success with reducing deforestation, in a large part by increasing command and control actions. Policies on climate change mitigation within the forest sector in Brazil are likely, on the one hand, to build on the country’s previous success in limiting deforestation through improved monitoring and enforcement, and on the other, to develop at least some component of transmitting financial benefit to landowners, through some form of payment for environmental services, building on pilot schemes in operation in the Atlantic Forest. It is possible to approach the development of scenarios for REDD+ based on these two main axes, with scenarios of high and low levels of command and control and high and low levels of incentives.
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Assessing climate model software quality: a defect density analysis of three models

Assessing climate model software quality: a defect density analysis of three models

Later on, he states that “individual metric measurements are of little use and [instead] combinations of metrics and some way of comparing their values against each other or against other populations is vital”. His proposal is to perform a demographic analysis – a comparison over a large popula- tion of codes – of software metrics in order to learn about the discriminating power of the measure in a real-world context. While an important future step, mining our arsenal of met- rics for strong correlations with our implicit notions of soft- ware quality, which we believe this approach boils down to, cannot define the entire research program. There is a deeper problem which must be addressed first: our notion of soft- ware quality with respect to climate models is theoretically and conceptually vague. It is not clear to us what differen- tiates high from low quality software, nor is it clear which aspects of the models or modelling processes we might reli- ably look to make to that assessment. If we do not get clear on what we mean by software quality first, then we have no way to assess what any empirical test is measuring, and so we will have no way to accept or reject measures as truly indicative of quality. We will not be doing science.
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Rev. adm. empres.  vol.56 número2

Rev. adm. empres. vol.56 número2

Green microinance is a new research ield that has emerged from the combination of two a priori distinct concepts: microinance (MF) and climate change (CC). For many decades, climate change seemed a luxury that the microinance industry could not aford or dream of (McKee, 2008, p. 2). However, the last decade witnessed a growing perception that “incorporating a climate change lens to microinance is essential and urgent […] as well as critical to the future of the sector” (McKee, 2008). In fact, due to their low adaptive ability, the millions of microinance clients globally are the most vulnerable to climate variability and their “plight is linked to the ability of microinance institutions (MFIs) to adapt to the consequences arising from climate change” (Dowla, 2009, p. 1). It is then in this a priori alien terrain that green microinance comes to light as an attempt to supplement microinanced products and services with tailored pro-poor climate change strategies with a view to enhancing the adaptive capacity of millions of MF clients worldwide. But should microinance or, more broadly, inclusive inancial services really be used to achieve such purposes? In other words, why should microinance actors care about weather extremes and CC at all, and what can they do to alleviate the climatic burden on the poor, which are after all their main target?
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Rev. Bras. Econ.  vol.64 número4

Rev. Bras. Econ. vol.64 número4

The least benefited sector was Leather and shoes and its performance can be explained by the fall of quantity produced, basically due to decline in exports and consumption. The effects on Coffee and Sugar industries are understood by a similar explanation. The effects on Steel industry and Retail/Wholesale trade are explained in a different way. These two sectors were benefited in the taxation reform by paying lower indirect taxes amounts that reduced their production prices. Besides this price decrease, the Steel industry also presented fall of output due to the reduction of its domestic sales and exports. In the case of the Retail/Wholesale trade the increase in output was not strong enough to offset the effects on prices.
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A modeling approach to determine the impacts of land use and climate change scenarios on the water flux of the upper Mara River

A modeling approach to determine the impacts of land use and climate change scenarios on the water flux of the upper Mara River

values were taken as a fairly good accuracy considering the heterogeneity of the study area that may pose significant difficulties using different classification methods. The error matrix indicated that there was substantial confusion between bushland, forest and grassland which was attributed to the selection of training data and also the fact that use of spectral and texture data alone were not capable of accurately distinguishing

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Climate impacts research: beyond patchwork

Climate impacts research: beyond patchwork

Cescatti, A., Chen, J., de Jeu, R., Dolman, A. J., Eugster, W., Gerten, D., Gianelle, D., Gobron, N., Heinke, J., Kimball, J., Law, B. E., Montagnani, L., Mu, Q., Mueller, B., Oleson, K., Papale, D., Richardson, A. D., Roupsard, O., Running, S., Tomelleri, E., Viovy, N., Weber, U., Williams, C., Wood, E., Zaehle, S., and Zhang, K.: Recent decline in the global land evapotranspiration trend due to limited moisture supply, Nature, 467, 951–954, 2010.

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Senstitivity of water balance components to environmental changes in a mountainous watershed: uncertainty assessment based on models comparison

Senstitivity of water balance components to environmental changes in a mountainous watershed: uncertainty assessment based on models comparison

can introduce further error. Testing of model estimates against measured evapotranspi- ration data across a range of vegetation types would be required to determine whether or not the additional physiological realism in RHESSys actually produces more accu- rate estimates, relative to SWAT. Regarding snow, both models simulate a decrease of SWE when climate scenarios are considered, and this seems to be the main cause for

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Climate model based consensus on the hydrologic impacts of climate change to the Rio Lempa basin of Central America

Climate model based consensus on the hydrologic impacts of climate change to the Rio Lempa basin of Central America

effects have been estimated to be of approximately equal magnitude, effectively can- celing each other and leaving the net effect equal to that of warming alone (Levis et al., 2000), though local impacts could be debated (Leipprand and Gerten, 2006). Thus, the results obtained here are plausibly representative of the sensitivity of the hydrologic system to climate change. An additional study with a biophysical model for this specific

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Impacts of climate change on the global potential distribution of two notorious invasive crayfishes

Impacts of climate change on the global potential distribution of two notorious invasive crayfishes

Our results have important implications for the management of both invasive species. Under global warming, the distribution of P. leniuscu- lus and P. clarkii is predicted to expand northward in Europe where this species already occurs. Early monitoring programmes and preventative measures should be considered to control spread of the two invasive species in Europe. In this sense, the European Union (EU) is committed with this environmental problem and has regulated a set of measures across the EU that includes prevention, early detection–eradication, and management of invasive species, as well as the financial support systems to implement such measures (European Parliament, 2014). However, the implementation of such measures depends on societal and political issues in each EU member country, which can reduce their effective- ness. Early detection of alien crayfish species may be performed using environmental DNA (eDNA) techniques (Muha, Rodríguez-Rey, Rolla, & Tricarico, 2017). Species-specific eDNA primers are available for both P. leniusculus (Larson et al., 2017) and P. clarkii (Tréguier et al., 2014). In areas where the dispersal of invasive crayfish species seems unavoid- able, mitigation management strategies to conserve vulnerable wildlife may also be planned prior to the arrival of the invaders. For example, both P leniusculus and P. clarkii have been reported to displace native crayfish through predation, competitive exclusion or transmission of dis- eases in Japan and Europe. In such areas, captive populations of native crayfish may be established before extirpation by crayfish invaders.
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Análise do risco de ocorrência da monilíase em cacaueiro no Brasil face às mudanças climáticas globais

Análise do risco de ocorrência da monilíase em cacaueiro no Brasil face às mudanças climáticas globais

The Ministry of Agriculture, Livestock and Food Supply (MAPA) developed a contingency plan of moniliasis. The aim of this program is to prevent the entry and spread of moniliasis in Brazil, and hold fast action to eradicate foci after detection (9). In the states with high risk of introduction this disease (Acre, Amazonas, Roraima and Rondônia), the contingency plan of moniliasis determines at least one prospecting per year in areas of species of Theobroma and Herrania wild and cultivated (9). Additionally, the MAPA and Agency of Agricultural Defense of Bahia (Adab) founded in 2011 the Technical Committee of Prevention Moniliasis of Cocoa (CTPMC). The CTPMC aims to develop actions to prevent the entry and establishment of moniliasis of cacao in the state Bahia, through integrated activities of research, technical assistance, education and plant health protection. Currently, moniliasis has widespread distribution in Peru, which in dicates good adaptation of th e path ogen and host to those environmental conditions. These conditions favored the wide spread of the disease, which affected the entire country in a short period of time (27). A similar situation occurred in Costa Rica, where moniliasis spread rapidly between 1978 and 1981 (11). Therefore, given the lack of efficient management methods to control moniliasis and the existence of risk areas in Brazil, this disease presents a serious threat to the national cocoa crop. In addition to these factors, the absence of pathogens antagonists to moniliasis in Brazil may compound losses from the onset of this disease in the country.
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Assessing the impacts of mining activities on zooplankton functional diversity

Assessing the impacts of mining activities on zooplankton functional diversity

In aquatic ecosystems, the availability and quality of food are considered to be crucial biotic constraints on the life history and survival of zooplankton, especially small freshwater herbivores (Romanovsky, 1985; De Mott, 1988; Elser, 2000; Czerniawski & Domagala, 2014). Several studies indicate that suspended sediments may affect the abundance of cladocerans, by decreasing their survival and fecundity (Hart, 1987; McCabe & O’Brien, 1983). In other tropical systems with high turbidity, small cladocerans such as Bosmina and Bosminopsis can reach significant densities (Zettler & Carter, 1986). The feeding mode of these crustaceans may be the key to their survival in these restrictive environments. These small cladocerans ingest suspended sediment particles as well as particles in a size range of 1-15 μm, with equal efficiencies, and their ingestion of sediments is associated with decreased ingestion of phytoplankton cells (De Mott, 1982). Inorganic particles may be an alternative food source for cladocerans, which under natural conditions of low algal productivity and large amounts of suspended particles, can use the organic substrate adsorbed by mineral particles, since these particles are within the size range of the normally consumed algae particles (Arruda et al., 1983; Kirk, 1991).
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Potential impacts of climate change on insect communities: a transplant experiment.

Potential impacts of climate change on insect communities: a transplant experiment.

We found that when differences in guild structure occurred, they were mainly driven by a reduction of sapsuckers and an increase of predators and scavengers at the warm sites (see Fig. 2). This suggests that predators and scavengers may benefit from warmer temperatures in the future. Similarly, increased temper- ature in an old-field experiment led to a distinct shift in guild structure, where numbers of predators significantly increased [24]. Coleoptera and Hemiptera feeding guild structure showed little consistency between the control site and W2, with seven of the eight plant species supporting significantly different proportions of feeding guilds. These differences were mainly driven by either higher numbers of fungivores (D. corymbosa, A. hispida and C. pinifolius) or fewer sapsuckers (A. obtusata, A. parvipinnula, L. squarrosum, H. gibbosa and T. speciosissima) at W2. The most likely factors contributing to these differences include the differences in structural complexity and plant species composition at W2. It has been shown previously that variations in structural complexity of sward, located at field margins in Great Britain, had a significant effect on the arthropod community structure [82], with phytoph- agous groups responding differently to an increase of structural complexity than predatory groups.
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This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives

This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives

according to the LAEP perspective, given the existence of growing inter- national competition and increasing cross-border capital flows, the adoption of RFBs for “consumption rights” in countries eager to promote social justice by drastically and quickly expanding the enjoyment of ESCRs may take a toll on the ability of the local economy to compete internationally.63 Thus reforms in the policy areas concerning “produc- tion rights” should require that the M’ component of RFBs must be pegged to an interest rate index that compounds selected yields of finan- cial markets (e.g., markets for financial derivatives) and capital markets (stock exchanges).64 This results from the fact that, in the context of open economies, a persistent lag between the return to productive invest- ment and interest rates may negatively affect capital formation and even cause disinvestment and capital flight. According to the LAEP approach, the contractual architectonics of the national economy must “balance” the protection of consumption rights with the ability of commercial property holders to keep a competitive edge in the global economy. For this reason, an index or “basket” of interest rates taken from the most important financial markets around the world must remain an impor- tant reference for the formulation of RFBs applied to the enjoyment of “production rights” and for the conduct of international commercial or monetary cooperation. Moreover, in the reform efforts oriented to enhance the protection of consumption rights, interest rates prevailing in relevant public finance arrangements attendant to such reforms must also be considered in legal analysis.
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Projected climate change impacts on North Sea and Baltic Sea:   CMIP3 and CMIP5 model based scenarios

Projected climate change impacts on North Sea and Baltic Sea: CMIP3 and CMIP5 model based scenarios

sistent than that of SST and sea ice extend. The ensemble means show a reduction in salinity for the North Sea and the Baltic Sea for both, the CMIP3 and CMIP5 sce- narios (Fig. 7a and b), A two-sample T test is used on the annual averages from the 30 years time periods to determine the significance (at the 5 % level). However, the pro- jected changes vary strongly with the parent ESM forcing, and an exceptional increase

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Assessing the ability of three land ecosystem models to simulate gross carbon uptake of forests from boreal to Mediterranean climate in Europe

Assessing the ability of three land ecosystem models to simulate gross carbon uptake of forests from boreal to Mediterranean climate in Europe

Our primary goal is to assess the general correspondence of European scale simulations and eddy covariance based GPP along the MAT gradient. Thus we used the same driver data as previous modelling studies of Carboeurope-IP (Jung et al., 2007; Vetter et al., 2007). This approach has the ad- vantage that model evaluation is facilitated at their scale of application, i.e. continental to global including all uncertain- ties involved in large scale modelling. However, it trades-off to some extent with the identification of model structural un- certainties and unambiguous identification of which model performs best since input data effects can not be separated. Substantial deviation between the rather coarse soil and me- teo input data and in situ conditions at the measurement sites can be expected due to small scale variability (esp. convec- tive rainfall, cloudiness, soil structure and depth) and general uncertainties regarding the quality of the coarse scale model input. Considering input data effects and uncertainties of the GPP estimates from Carboeurope sites, the absolute simu- lated GPP values may be considered to be in the range of the uncertainty of our approach. Complementary, to this ex- tensive data-model comparison study that covers well large climate gradients of Europe, we are currently undertaking effort to better understand real and model world controls of GPP variations for a few selected sites using in-situ measured model driver data.
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Augusto Sousa Miranda1 , Felipe Nogueira Domingues2 , Bruno Spacek Godoy3 , Ricardo Pedroso Oaigen

Augusto Sousa Miranda1 , Felipe Nogueira Domingues2 , Bruno Spacek Godoy3 , Ricardo Pedroso Oaigen

ABSTRACT - The objective of this study was to evaluate the chemical composition and yield of three sugarcane cultivars grown under Af climate conditions. Three sugarcane cultivars were examined, namely, IACSP93-6006, RB83-5486, and SP79-1011, in a randomized block design with three treatments, four blocks, and two replicates per block; means were compared using Tukey’s test at 5% probability level. Significant differences were observed for dry matter, ether extract, crude protein, acid detergent fiber, lignin (LIG), cellulose, neutral detergent fiber corrected for ash and protein (NDFap), total carbohydrates, carbohydrate fractions B2 and C, and dry matter yield. The fiber components (NDFap, LIG, and fraction C) displayed low values. The cultivars produced high dry matter yields, especially IACSP93-6006 and SP79-1011. There were no differences among sucrose (Pol) values and the NDF/Pol ratios. The low Pol values indicate that sugarcane grown under Af climate conditions does not produce high levels of sucrose. The three sugarcane cultivars grown under the Af climate conditions produce high yields of DM/ha but low concentrations of the fiber components, as well as low Pol concentrations.
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The impacts of future climate change and sulphur emission reductions on acidification recovery at Plastic Lake, Ontario

The impacts of future climate change and sulphur emission reductions on acidification recovery at Plastic Lake, Ontario

proach is similar to previous linked model systems that use hydrochemical effects mod- els (Forsius et al., 1997; Kaste et al., 2006). The ultimate goal of the model chain was to provide high-resolution inputs of climate and catchment discharge to drive aquatic DOC inputs and redox processes within MAGIC. The National Centre for Environmen- tal Prediction (NCEP) re-analysis data set (Kalnay et al., 1996) were used in conjunc-

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Climate change impacts on river discharge in West Africa: a review

Climate change impacts on river discharge in West Africa: a review

River discharge is affected by several drivers such as land use changes, water with- drawals and climate variations. As underlined by the above example, variability in cli- mate, and especially in rainfall, plays a significant role in flow variation in WA. In view of global warming, which will affect key climate variables such as rainfall and tempera- ture, changes in hydrological regimes could become even more important in the future.

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