1,326 research outputs found
Addressing risks to biodiversity arising from a changing climate: the need for ecosystem restoration in the Tana River Basin, Kenya
Climate change is projected to have significant effects on the distribution of species globally, but research into the implications in parts of Africa has been limited. Using species distribution modelling, this study models climate change-related risks to the terrestrial biodiversity (birds, mammals, reptiles, amphibians and plants) of Kenyaâs economically-important and ecologically diverse Tana River Basin. Large reductions in species richness are projected with just 2°C warming (relative to preindustrial levels) with birds and plants seeing the greatest impact. Potential climate refugia for biodiversity are identified within the basin, but often overlap with areas already converted to agriculture or set aside for agricultural expansion, and the majority are outside protected areas. Similarly, some protected areas contain no projected refugia at higher levels of global warming, showing they may be insufficient to protect the basinâs biodiversity as climate changes. However, risks to biodiversity are much smaller if the Paris Agreementâs goal of limiting global warming to âwell below 2°Câ warming, rather than 2°C only, is met. The potential for refugia for plants and animals decreases strongly with warming. For example, 82% of the basin remaining climatically suitable for at least 75% of the plants currently present at 1.5°C warming, as compared with 23% at 2°C and 3% at 4.5°C. This research provides the first assessment of the combined effects of development plans and climate change on biodiversity of the Tana River Basin, including identifying potential areas for restoration, and contributes to a greater understanding of biodiversity protection and adaptation options in Kenya
Quantifying the impact of climate change on drought regimes using the Standardised Precipitation Index
The study presents a methodology to characterise short- or long-term drought events, designed to aid understanding of how climate change may affect future risk. An indicator of drought magnitude, combining parameters of duration, spatial extent and intensity, is presented based on the Standardised Precipitation Index (SPI). The SPI is applied to observed (1955â2003) and projected (2003â2050) precipitation data from the Community Integrated Assessment System (CIAS). Potential consequences of climate change on drought regimes in Australia, Brazil, China, Ethiopia, India, Spain, Portugal and the USA are quantified. Uncertainty is assessed by emulating a range of global circulation models to project climate change. Further uncertainty is addressed through the use of a high-emission scenario and a low stabilisation scenario representing a stringent mitigation policy. Climate change was shown to have a larger effect on the duration and magnitude of long-term droughts, and Australia, Brazil, Spain, Portugal and the USA were highlighted as being particularly vulnerable to multi-year drought events, with the potential for drought magnitude to exceed historical experience. The study highlights the characteristics of drought which may be more sensitive under climate change. For example, on average, short-term droughts in the USA do not become more intense but are projected to increase in duration. Importantly, the stringent mitigation scenario had limited effect on drought regimes in the first half of the twenty-first century, showing that adaptation to drought risk will be vital in these regions
Advancing national climate change risk assessment to deliver national adaptation plans
A wide range of climate vulnerability and risk assessments have been implemented using different approaches at different scales, some with a broad multi-sectoral scope and others focused on single risks or sectors. This paper describes the novel approach to vulnerability and risk assessment which was designed and put into practice in the United Kingdom's Second Climate Change Risk Assessment (CCRA2) so as to build upon its earlier assessment (CCRA1). First, we summarize and critique the CCRA1 approach, and second describe the steps taken in the CCRA2 approach in detail, providing examples of how each was applied in practice. Novel elements of the approach include assessment of both present day and future vulnerability, a focus on the urgency of adaptation action, and a structure focused around systems of receptors rather than conventional sectors. Both stakeholders and reviewers generally regarded the approach as successful in providing advice on current risks and future opportunities to the UK from climate change, and the fulfilment of statutory duty. The need for a well-supported and open suite of impact indicators going forward is highlighted
Qatar-2: A K dwarf orbited by a transiting hot Jupiter and a more massive companion in an outer orbit
We report the discovery and initial characterization of Qatar-2b, a hot
Jupiter transiting a V = 13.3 mag K dwarf in a circular orbit with a short
period, P_ b = 1.34 days. The mass and radius of Qatar-2b are M_p = 2.49 M_j
and R_p = 1.14 R_j, respectively. Radial-velocity monitoring of Qatar-2 over a
span of 153 days revealed the presence of a second companion in an outer orbit.
The Systemic Console yielded plausible orbits for the outer companion, with
periods on the order of a year and a companion mass of at least several M_j.
Thus Qatar-2 joins the short but growing list of systems with a transiting hot
Jupiter and an outer companion with a much longer period. This system
architecture is in sharp contrast to that found by Kepler for multi-transiting
systems, which are dominated by objects smaller than Neptune, usually with
tightly spaced orbits that must be nearly coplanar
On the Importance of the Flare's Late Phase for the Solar Extreme Ultraviolet Irradiance
The new solar extreme ultraviolet (EUV) irradiance observations from NASA Solar Dynamics Observatory (SDO) have revealed a new class of solar flares that are referred to as late phase flares. These flares are characterized by the hot 2-5 MK coronal emissions (e.g., Fe XVI 33.5 nm) showing large secondary peaks that appear many minutes to hours after an eruptive flare event. In contrast, the cool 0.7-1.5 MK coronal emissions (e.g., Fe IX 17.1 nm) usually dim immediately after the flare onset and do not recover until after the delayed second peak of the hot coronal emissions. We refer to this period of 1-5 hours after the fl amrea sin phase as the late phase, and this late phase is uniquely different than long duration flares associated with 2-ribbon flares or large filament eruptions. Our analysis of the late phase flare events indicates that the late phase involves hot coronal loops near the flaring region, not directly related to the original flaring loop system but rather with the higher post-eruption fields. Another finding is that space weather applications concerning Earth s ionosphere and thermosphere need to consider these late phase flares because they can enhance the total EUV irradiance flare variation by a factor of 2 when the late phase contribution is included
Projected risks associated with heat stress in the UK Climate Projections (UKCP18)
Summer heat extremes in the UK pose a risk to health (amongst other sectors) and this is exacerbated by localised socio-economic factors that contribute to vulnerability. Here, regional climate model simulations from the UK Climate Projections are used to assess how different elements of extreme heat will vary across the UK in the future under global mean surface temperature warming levels of +1.5 °C, +2.0 °C and +3.0 °C above pre-industrial. Heat stress metrics incorporating daily maximum and minimum temperature, temperature variability and vapour pressure are included. These show qualitatively similar spatial patterns for the recent past, with the most pronounced heat hazards found in south-eastern regions of the UK. Projected heat hazard changes across the UK are not homogeneous, with southern regions (e.g. Greater London, South East) showing greater increases in maximum temperatures and northern regions (e.g. Scotland and Northern Ireland) showing greater increases in humidity. With +3.0 °C warming, the relative change in combined heat hazards is found to be greatest in the south-western UK, however, in absolute terms, south-eastern regions will still experience the greatest hazards. When combined with socio-economic factors, hotspots of high heat stress risk emerge in parts of London, the Midlands and eastern England along with southern and eastern coastal regions. Weighting of different heat risk factors is subjective and to this end we have developed and made available an interactive app which allows users to assess sensitivities and uncertainties in the projected UK heat risk
Environmental influences on human innovation and behavioural diversity in southern Africa 92â80 thousand years ago
Attitudes toward Precision Treatment of Smoking in the Southern Community Cohort Study
Background: Precision interventions using biological data may enhance smoking treatment, yet are understudied among smokers who are disproportionately burdened by smoking-related disease. Methods: We surveyed smokers in the NCI-sponsored Southern Community Cohort Study, consisting primarily of African-American, low-income adults. Seven items assessed attitudes toward aspects of precision smoking treatment, from undergoing tests to acting on results. Items were dichotomized as favorable (5 = strongly agree/4 = agree) versus less favorable (1 = strongly disagree/2 = disagree/3 = neutral); a summary score reflecting generalized attitudes was also computed. Multivariable logistic regression tested independent associations of motivation (precontemplation, contemplation, and preparation) and confidence in quitting (low, medium, and high) with generalized attitudes, controlling for sociodemographic factors and nicotine dependence. Results: More than 70% of respondents endorsed favorable generalized attitudes toward precision medicine, with individual item favorability ranging from 64% to 83%. Smokers holding favorable generalized attitudes reported higher income and education (P \u3c 0.05). Predicted probabilities of favorable generalized attitudes ranged from 63% to 75% across motivation levels [contemplation vs. precontemplation: adjusted odds ratio (AOR) = 2.10, 95% confidence interval (CI), 1.36â3.25, P = 0.001; preparation vs. precontemplation: AOR = 1.83, 95% CI, 1.20â2.78, P = 0.005; contemplation vs. preparation: AOR = 1.15, 95% CI, 0.75â1.77, P = 0.52] and from 59% to 78% across confidence (medium vs. low: AOR = 1.91, 95% CI, 1.19â3.07, P = 0.007; high vs. low: AOR = 2.62, 95% CI, 1.68â4.10, P \u3c 0.001; medium vs. high: AOR = 0.73, 95% CI, 0.48â1.11, P = 0.14). Conclusions: Among disproportionately burdened community smokers, most hold favorable attitudes toward precision smoking treatment. Individuals with lower motivation and confidence to quit may benefit from additional intervention to engage with precision smoking treatment. Impact: Predominantly favorable attitudes toward precision smoking treatment suggest promise for future research testing their effectiveness and implementation
Predicting the Impact of Climate Change on Threatened Species in UK Waters
Global climate change is affecting the distribution of marine species and is thought to represent a threat to biodiversity. Previous studies project expansion of species range for some species and local extinction elsewhere under climate change. Such range shifts raise concern for species whose long-term persistence is already threatened by other human disturbances such as fishing. However, few studies have attempted to assess the effects of future climate change on threatened vertebrate marine species using a multi-model approach. There has also been a recent surge of interest in climate change impacts on protected areas. This study applies three species distribution models and two sets of climate model projections to explore the potential impacts of climate change on marine species by 2050. A set of species in the North Sea, including seven threatened and ten major commercial species were used as a case study. Changes in habitat suitability in selected candidate protected areas around the UK under future climatic scenarios were assessed for these species. Moreover, change in the degree of overlap between commercial and threatened species ranges was calculated as a proxy of the potential threat posed by overfishing through bycatch. The ensemble projections suggest northward shifts in species at an average rate of 27 km per decade, resulting in small average changes in range overlap between threatened and commercially exploited species. Furthermore, the adverse consequences of climate change on the habitat suitability of protected areas were projected to be small. Although the models show large variation in the predicted consequences of climate change, the multi-model approach helps identify the potential risk of increased exposure to human stressors of critically endangered species such as common skate (Dipturus batis) and angelshark (Squatina squatina)
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