scholarly journals ‘Tales of Symphonia ’: extinction dynamics in response to past climate change in Madagascan rainforests

2009 ◽  
Vol 5 (6) ◽  
pp. 821-825 ◽  
Author(s):  
Malika Virah-Sawmy ◽  
Michael B. Bonsall ◽  
Katherine J. Willis
Keyword(s):  
Climate Change ◽  
Climatic Variability ◽  
Regional Climate ◽  
Population Level ◽  
Valuable Insight ◽  
Important Species ◽  
Model Predictions ◽  
Past Climate Change ◽  
Regional Fluctuations ◽  
Insight Into

Madagascar's rainforests are among the most biodiverse in the world. Understanding the population dynamics of important species within these forests in response to past climatic variability provides valuable insight into current and future species composition. Here, we use a population-level approach to analyse palaeoecological records over the last 5300 years to understand how populations of Symphonia cf. verrucosa became locally extinct in some rainforest fragments along the southeast coast of Madagascar in response to rapid climate change, yet persisted in others. Our results indicate that regional (climate) variability contributed to synchronous decline of S . cf. verrucosa populations in these forests. Superimposed on regional fluctuations were local processes that could have contributed or mitigated extinction. Specifically, in the forest with low soil nutrients, population model predictions indicated that there was coexistence between S . cf. verrucosa and Erica spp., but in the nutrient-rich forest, interspecific effects between Symphonia and Erica spp. may have pushed Symphonia to extinction at the peak of climatic change. We also demonstrate that Symphonia is a good indicator of a threshold event, exhibiting erratic fluctuations prior to and long after the critical climatic point has passed.

scholarly journals Climate change enhances disease processes in crustaceans: case studies in lobsters, crabs, and shrimps

2019 ◽  
Author(s):  
Jeffrey D Shields
Keyword(s):  
Climate Change ◽  
Multiple Stressors ◽  
Population Level ◽  
Microbial Pathogens ◽  
Important Species ◽  
Immunological Responses ◽  
Developmental Rates ◽  
Commercially Important ◽  
Physiological Demands ◽  
Increasing Temperature

Abstract Climate change has resulted in increasing temperature and acidification in marine systems. Rising temperature and acidification act as stressors that negatively affect host barriers to infection, thus enhancing disease processes and influencing the emergence of pathogens in ecologically and commercially important species. Given that crustaceans are ectotherms, changes in temperature dominate their physiological and immunological responses to microbial pathogens and parasites. Because of this, the thermal ranges of several crustacean hosts and their pathogens can be used to project the outcomes of infections. Host factors such as molting, maturation, respiration, and immune function are strongly influenced by temperature, which in turn alter the host’s susceptibility to pathogens, further amplifying morbidity and mortality. Microbial pathogens are also strongly influenced by temperature, arguably more so than their crustacean hosts. Microbial pathogens, with higher thermal optima than their hosts, grow rapidly and overcome host immune defenses, which have been weakened by increased temperatures. Pathogen factors such as metabolic rates, growth rates, virulence factors, and developmental rates are often enhanced by rising temperature, which translates into increased transmission, dispersal, and proliferation at the population level, and ultimately emergence of outbreaks in host populations. Less well known are the effects of acidification and salinity intrusion on host-pathogen processes, but they operate alongside temperature, as multiple stressors, that impose significant metabolic and physiological demands on host homeostasis.

Probabilistic projection of the regional climate as the basis for the development of adaptation programs in the economy of Russia

2021 ◽  
Author(s):  
Yuliya Rudakova ◽  
Igor Shkolnik ◽  
Elena Khlebnikova ◽  
Vladimir Kattsov
Keyword(s):  
Climate Change ◽  
Boundary Conditions ◽  
Thermal Regime ◽  
Initial Conditions ◽  
Climatic Variability ◽  
Regional Climate ◽  
Cmip5 Models ◽  
Northern Eurasia ◽  
Climate Projections ◽  
Russian Science

<p>The prospects of using the probabilistic regional climate projection technique for adaptation to climate change in the territory of Russia are considered. The analysis focuses on future changes in the climatic indicators of the thermal regime and humidification which play a significant role in the evaluation of the reliability of the functioning of construction and technical systems as well as transport and energy infrastructure.</p><p>The analysis is based on the output of the 50-member ensemble of high-resolution climate projections using an RCM developed at the Main Geophysical Observatory (MGO). The RCM grid has a horizontal resolution of 25 km across Russia. Modeling projections have been recently used to assess the impacts of regional climate change on hydropower facilities (Shkolnik et al., 2018).</p><p>Numerical experiments are carried out from different (random) initial conditions for the baseline 1990-1999 and future periods 2050-2059 and 2090-2099 using the IPCC RCP8.5 scenario (Kattsov et al., 2020). The boundary conditions on the ocean surface are derived from the output of the five CMIP5 models. For each ocean state trajectory, ten experiments from the different initial conditions are conducted. Lateral boundary conditions for the RCM ensemble are provided by MGO AGCM under an identical experimental setup.</p><p>To study the future impacts of the thermal regime, several universal indicators are used, particularly, the annual and seasonal extremes of temperature for a given averaging period as well as the characteristics of intra-annual periods with the temperature above/below the thresholds. The thresholds ​​are selected to meet the needs of construction, land transport, and the energy sector. Besides, the indicators of the precipitation regime are considered (seasonal maxima of daily amounts and characteristics of dry/wet periods).</p><p>Along with obtaining median ensemble estimates of changes in mean values, an analysis of future changes in the indicators in the probabilistic aspect is conducted. Using the temperature of the hottest 30-day period and the maximum duration of the dry period, the regional features of their projected changes are demonstrated accounting for the contribution of internal climatic variability. In agreement with observations, significant differences in the changes between the European part of Russia and certain regions of its Asian part are revealed.</p><p>The study is supported by the Russian Science Foundation (grant 16-17-00063).</p><p><strong>References</strong></p><p>Kattsov V., E. Khlebnikova, I. Shkolnik, and Yu. Rudakova: Probabilistic Regional Climate Projecting as a Basis for the Development of Adaptation Programs for the Economy of the Russian Federation. Russian Meteorology and Hydrology, 2020, Vol. 45, No. 5, pp. 330–338. Allerton Press, Inc., 2020.</p><p>Shkolnik, I., Pavlova, T., Efimov, S. et al. Future changes in peak river flows across northern Eurasia as inferred from an ensemble of regional climate projections under the IPCC RCP8.5 scenario. Clim Dyn 50<strong>, </strong>215–230 (2018). https://doi.org/10.1007/s00382-017-3600</p>

scholarly journals A Multivariate Approach to Determine the Dimensionality of Human Facial Asymmetry

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 348
Author(s):  
Omid Ekrami ◽  
Peter Claes ◽  
Julie D. White ◽  
Seth M. Weinberg ◽  
Mary L. Marazita ◽  
...  
Keyword(s):  
Individual Variation ◽  
Facial Asymmetry ◽  
Population Level ◽  
Directional Asymmetry ◽  
Main Step ◽  
Valuable Insight ◽  
Biological Processes ◽  
Measure Of Asymmetry ◽  
Different Dimensions ◽  
Insight Into

Many studies have suggested that developmental instability (DI) could lead to asymmetric development, otherwise known as fluctuating asymmetry (FA). Several attempts to unravel the biological meaning of FA have been made, yet the main step in estimating FA is to remove the effects of directional asymmetry (DA), which is defined as the average bilateral asymmetry at the population level. Here, we demonstrate in a multivariate context that the conventional method of DA correction does not adequately compensate for the effects of DA in other dimensions of asymmetry. This appears to be due to the presence of between-individual variation along the DA dimension. Consequently, we propose to decompose asymmetry into its different orthogonal dimensions, where we introduce a new measure of asymmetry, namely fluctuating directional asymmetry (F-DA). This measure describes individual variation in the dimension of DA, and can be used to adequately correct the asymmetry measurements for the presence of DA. We provide evidence that this measure can be useful in disentangling the different dimensions of asymmetry, and further studies on this measure can provide valuable insight into the underlying biological processes leading to these different asymmetry dimensions.

scholarly journals Looking for evidence of climate change impacts in the eastern Irish Sea

2011 ◽  
Vol 11 (6) ◽  
pp. 1641-1656 ◽  
Author(s):  
L. S. Esteves ◽  
J. J. Williams ◽  
J. M. Brown
Keyword(s):  
Climate Change ◽  
Wind Speed ◽  
Climate Models ◽  
Objective Assessment ◽  
Climatic Variability ◽  
Regional Climate ◽  
Shoreline Change ◽  
Irish Sea ◽  
Erosion Risk

Abstract. Although storminess is often cited as a driver of long-term coastal erosion, a lack of suitable datasets has only allowed objective assessment of this claim in a handful of case studies. This reduces our ability to understand and predict how the coastline may respond to an increase in "storminess" as suggested by global and regional climate models. With focus on 16 km of the Sefton coastline bordering the eastern Irish Sea (UK), this paper analyses available measured datasets of water level, surge level, wave height, wind speed and barometric pressure with the objective of finding trends in metocean climate that are consistent with predictions. The paper then examines rates of change in shoreline position over the period 1894 to 2005 with the aim of establishing relationships with climatic variability using a range of measured and modelled metocean parameters (with time spans varying from two to eight decades). With the exception of the mean monthly wind speed, available metocean data do not indicate any statistically significant changes outside seasonal and decadal cycles. No clear relationship was found between changes in metocean conditions and rates of shoreline change along the Sefton coast. High interannual variability and the lack of long-term measurements make unambiguous correlations between climate change and shoreline evolution problematic. However, comparison between the North Atlantic Oscillation winter index (NAOw) and coastline changes suggest increased erosion at times of decreasing NAOw values and reduced erosion at times of increasing NAOw values. Erosion tends to be more pronounced when decreasing NAOw values lead to a strong negative NAO phase. At present, anthropogenic changes in the local sediment budget and the short-term impact of extreme events are still the largest threat likely to affect coastal flooding and erosion risk in the short- and medium-term. Nevertheless, the potential impacts of climate change in the long-term should not be ignored.

Novel Approach to Model Static Recrystallization of Austenite during Hot-Rolling of Nb-Microalloyed Steel: Effect of Precipitates

2013 ◽  
Vol 753 ◽  
pp. 417-422 ◽  
Author(s):  
Kashif Rehman ◽  
Hatem S. Zurob
Keyword(s):  
Size Control ◽  
Quantitative Agreement ◽  
Valuable Insight ◽  
Physically Based Model ◽  
Novel Approach ◽  
Model Predictions ◽  
Physically Based ◽  
Grain Size Control ◽  
Nb Microalloyed Steel ◽  
Insight Into

Microalloying additions are critical for grain size control during thermo-mechanical processing. The addition of niobium is known to delay the onset and growth of recrystallization. A physically-based model for the interaction of strain-induced precipitation, recovery and recrystallization is presented. A key feature of the model is the incorporation of the effect of precipitation on the nucleation of recrystallization. Quantitative agreement between the experimental measurements and the model predictions has also been demonstrated. The model offers valuable insight into the relative contributions of solute and precipitate Nb as well as the optimum conditions for strain accumulation.

scholarly journals The World Heritage Naracoorte Caves beyond 500 ka: U-Pb dating and charcoal analysis from speleothems with implications for Pleistocene vertebrate fossil deposits

2021 ◽  
Author(s):  
Rieneke Weij ◽  
Jon Woodhead ◽  
Liz Reed ◽  
Kale Sniderman ◽  
John Hellstrom ◽  
...  
Keyword(s):  
Climate Change ◽  
World Heritage ◽  
Charcoal Analysis ◽  
Past Climate ◽  
The Past ◽  
Spin Resonance ◽  
The World ◽  
Past Climate Change ◽  
First Time ◽  
Insight Into

<p>Under the current rapid global warming, studying how environments responded to past climate change becomes increasingly important to better understand what impact climate variability has on regional flora and fauna. Our new multi-proxy study to the World Heritage Naracoorte Caves in southern Australia provides a unique window into the past climate as they are heavily decorated with speleothems but also contain in-fill deposits rich in Pleistocene vertebrate fossils including the extinct Australian megafauna. Until now, these speleothems have been dated using U-Th series and the fossil-bearing sediments with Optical Stimulated Luminescence and Electro Spin Resonance techniques, but only up to ca. 500 ka. We have U-Pb dated speleothems from the Naracoorte Caves for the first time and extended the record beyond 500 ka. We combined precise chronology with analyses of pollen and charcoal within the speleothems which allows us to better understand how southern Australia’s climate and its vegetation changed during the Quaternary. It also provides a unique insight into the timing and extent of cave opening with important potential for much older vertebrate fossil deposits than previously thought.</p>

scholarly journals Why Analyze Mental Models of Local Climate Change? A Case from Southern Mozambique

2011 ◽  
Vol 3 (4) ◽  
pp. 223-237 ◽  
Author(s):  
L. Jen Shaffer ◽  
Leocadia Naiene
Keyword(s):  
Climate Change ◽  
Mental Models ◽  
Climate Models ◽  
Environmental Changes ◽  
Regional Climate ◽  
Regional Climate Models ◽  
Fruit Production ◽  
Local Climate ◽  
Local Climate Change ◽  
Insight Into

Abstract People construct mental models of local climate change based on their observations and experiences of past climate events and changes. These mental models offer critical insight into locally important factors that trigger responses to new climate conditions and can be used to ground-truth regional climate models. In this paper, the authors explore mental models of changes to local climate patterns and climate-associated environmental changes over the past 45 years (1963–2008) in two rural communities in Matutúine District, Mozambique. Interview results are compared to data from a regional weather station. Residents discuss temperature increases, short-term and long-term precipitation changes, and altered seasonal timing. Measurable climate change in this region includes increasing temperatures and more erratic rainfall leading to drought and altered season timing. The climate-associated environmental changes residents observed draw attention to links between local livelihood practices and climate, as well as emphasize changes that would not necessarily appear in regional climate models. Such changes include reduced crop and wild fruit production, fewer cattle, variable forest size, increased wildfires and elephant conflict, drying up of water sources, poor health, and cultural change. Differences between adjacent communities highlight the potential interaction of landscape and vegetation variability, gender, and livelihoods in observations and experiences of climate change and demonstrate how mental models can provide insight into local ecological patterns and processes.

scholarly journals SDG 13 and the entwining of climate and sustainability metagovernance: an archaeological–genealogical analysis of goals-based climate governance

2020 ◽  
Vol 33 (7) ◽  
pp. 1731-1759
Author(s):  
Robert Charnock ◽  
Keith Hoskin
Keyword(s):  
Climate Change ◽  
Sustainable Development ◽  
Network Governance ◽  
Recent Measurement ◽  
Valuable Insight ◽  
Content Type ◽  
Truth Claims ◽  
Combat Climate Change ◽  
Insight Into ◽  
Urgent Action

PurposeThis paper brings insights from accounting scholarship to the measurement and reporting challenges of metagovernance approaches to sustainable development. Where scholarship on metagovernance—the combination of market, hierarchical and network governance—proposes deductive approaches to such challenges, we contend that a historically informed “abductive” approach offers valuable insight into the realpolitik of intergovernmental frameworks.Design/methodology/approachThe paper adopts a Foucauldian “archaeological–genealogical” method to investigate the inclusion of climate change as a Sustainable Development Goal (SDG). It analyses more than 100 documents and texts, tracking the statement forms that crystallise prevailing truth claims across the development of climate and SDG metagovernance.FindingsWe show how the truth claims now enshrined in the Paris Agreement on Climate Change constrained the conceptualisation and operationalisation of SDG 13: Take urgent action to combat climate change and its impacts. The paper thereby reframes recent measurement and reporting challenges as outcomes of conceptual conflicts between the technicist emphasis of divisions within the United Nations and the truth claims enshrined in intergovernmental agreements.Originality/valueThis paper demonstrates how an archaeological–genealogical approach may start to address the measurement and reporting challenges facing climate and SDG metagovernance. It also highlights that the two degrees target on climate change has a manifest variability of interpretation and shows how this characteristic has become pivotal to operationalising climate metagovernance in a manner that respects the sovereignty of developing nations.

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