Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CLIMATE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMed1994

Sensitivity of the terrestrial biosphere to climatic changes: impact on the carbon cycle.

The biosphere is a major pool in the global carbon cycle; its response to climatic change is therefore of great importance. We developed a 5 degrees x 5 degrees longitude-latitude resolution model of the biosphere in which the global distributions of the major biospheric variables, i.e. the vegetation types and the main carbon pools and fluxes, are determined from climatic variables. We defined nine major broad vegetation types: perennial ice, desert and semi-desert, tundra, coniferous forest, temperate deciduous forest, grassland and shrubland, savannah, seasonal tropical forest and evergreen tropical forest. Their geographical repartition is parameterized using correlations between observed vegetation type, precipitation and biotemperature distributions. The model computes as a function of climate and vegetation type, the variables related to the continental biospheric carbon cycle, i.e. the carbon pools such as the phytomass, the litter and the soil organic carbon; and carbon fluxes such as net primary production, litter production and heterotrophic respiration. The modeled present-day biosphere is in good agreement with observation. The model is used to investigate the response of the terrestrial biosphere to climatic changes as predicted by different General Circulation Models (GCM). In particular, the impact on the biosphere of climatic conditions corresponding to the last glacial climate (LGM), 18 000 years ago, is investigated. Comparison with results from present-day climate simulations shows the high sensitivity of the geographical distribution of vegetation types and carbon content as well as biospheric trace gases emissions to climatic changes. The general trend for LGM compared to the present is an increase in low density vegetation types (tundra, desert, grassland) to the detriment of forested areas, in tropical as well as in other regions. Consequently, the biospheric activity (carbon fluxes and trace gases emissions) was reduced.

Journal Article↗
PubMed1995

Sensitivity of a forest ecosystem model to climate parametrization schemes.

An analysis of the climate parametrization scheme adopted by conventional forest gap models revealed that most models assume a constant climate and are difficult to calibrate consistently. Tree growth showed unrealistically sensitive threshold effects along ecological gradients of temperature and precipitation. A new parametrization was compared with its predecessors in terms of the model's capability to predict realistic steady state species compositions at three test sites in the Alps. Applying the new model variant ForClim to some climate-change scenarios suggests that forest gap models are highly sensitive to climate pametrizations, regardless of the realism with which they simulate forests for the current climate. Moreover, the precision of climate scenarios based on General Circulation Models (GCM), for example, falls short of ForClim's sensitivity. Climate-dependent processes in forest gap models should be rehearsed before these models are used in impact studies of climatic change.

Journal Article↗
PubMed2002

Potential effect of population and climate changes on global distribution of dengue fever: an empirical model.

BACKGROUND: Existing theoretical models of the potential effects of climate change on vector-borne diseases do not account for social factors such as population increase, or interactions between climate variables. Our aim was to investigate the potential effects of global climate change on human health, and in particular, on the transmission of vector-borne diseases. METHODS: We modelled the reported global distribution of dengue fever on the basis of vapour pressure, which is a measure of humidity. We assessed changes in the geographical limits of dengue fever transmission, and in the number of people at risk of dengue by incorporating future climate change and human population projections into our model. FINDINGS: We showed that the current geographical limits of dengue fever transmission can be modelled with 89% accuracy on the basis of long-term average vapour pressure. In 1990, almost 30% of the world population, 1.5 billion people, lived in regions where the estimated risk of dengue transmission was greater than 50%. With population and climate change projections for 2085, we estimate that about 5-6 billion people (50-60% of the projected global population) would be at risk of dengue transmission, compared with 3.5 billion people, or 35% of the population, if climate change did not happen. INTERPRETATION: We conclude that climate change is likely to increase the area of land with a climate suitable for dengue fever transmission, and that if no other contributing factors were to change, a large proportion of the human population would then be put at risk.

Aedes↗
PubMed2001

The emotional climate of care-giving in home-care services.

The emotional aspects of the care-giving relationship in home-care services are studied, starting from the home-care recipients' and the home-care workers' perception of the emotional climate. Their experiences of the care-giving relationship and the influence from different aspects of the care-giving situation and social processes in the work organisation are explored. Two hundred and twenty-two recipients and their home-care workers in three typical Swedish municipalities were studied. The emotional climate is described with the help of a scale of 85 adjectives. Results show that home-care workers are more likely to experience the climate with a higher degree of emotionality. There is symmetry between the parties in the perception of a negative climate. However, if one party perceives the climate as close the other party is more likely to perceive it as rational or instrumental. The organisational processes, especially the group climate of the work team, principally influence the home-care recipients' perceptions. The workers' perceptions are principally influenced by age and gender of the recipients and the workers' own age. The emotional climate is constructed in a process between the parties, depending on their responses to each other. Tendencies to perceive a specific climate are strengthened or weakened by context variables and this in turn changes the care-giving interaction.

Aged↗
PubMed2005

Climatic unpredictability and parasitism of caterpillars: implications of global warming.

Insect outbreaks are expected to increase in frequency and intensity with projected changes in global climate through direct effects of climate change on insect populations and through disruption of community interactions. Although there is much concern about mean changes in global climate, the impact of climatic variability itself on species interactions has been little explored. Here, we compare caterpillar-parasitoid interactions across a broad gradient of climatic variability and find that the combined data in 15 geographically dispersed databases show a decrease in levels of parasitism as climatic variability increases. The dominant contribution to this pattern by relatively specialized parasitoid wasps suggests that climatic variability impairs the ability of parasitoids to track host populations. Given the important role of parasitoids in regulating insect herbivore populations in natural and managed systems, we predict an increase in the frequency and intensity of herbivore outbreaks through a disruption of enemy-herbivore dynamics as climates become more variable.

Animals↗
PubMed1998

Perceived motivational climate and cognitive and affective correlates among Norwegian athletes.

Based on Ames' conception of situational goal structures, the present study investigated whether achievement-related cognitions and affect were related to specific motivational climates. The participants were 148 experienced students in team sport at a Norwegian university who responded to a questionnaire on their perceptions of the motivational climate in their sport, use of learning strategies, satisfaction, sources of satisfaction and perceived purposes of participating in sport. Canonical correlation analysis revealed that the perception of the motivational climate as either mastery- or performance-involving was related to reporting of affect, achievement strategies and perceived purposes of sport in a conceptually consistent manner. Controlling for dispositional goals, regression analyses, in which the athletes' dispositional achievement goals were controlled, showed that perception of a performance-oriented climate emerged as a negative and unique predictor of satisfaction or interest in addition to the variance accounted for by ego orientation. Athletes who perceived the motivational climate as mastery-oriented endorsed mastery as a source of satisfaction, and were less inclined to report avoiding practice. In addition, athletes who perceived the climate as mastery-oriented believed that sport may develop lifetime skills. In contrast, perceiving the climate as performance-oriented was positively related to status as a perceived purpose of team sport. Our findings suggest that, when athletes perceive the sport climate as task-involving, it facilitates the adoption of adaptive learning strategies, the use of controllable criteria to determine satisfaction, and enhances perception of sport as being important for developing lifetime skills.

Achievement↗
PubMed1998

The relationship between competitive anxiety, achievement goals, and motivational climates.

The purpose of this study was to examine the relationships of achievement goal orientations and perceived motivational climate to perceptions of the intensity and direction of competitive state anxiety in a sample of university athletes representing various team sports. Although some studies have demonstrated that task orientation and mastery climate are associated with adaptive emotional patterns and ego orientation and performance climate are linked to less adaptive emotions, others have not verified these findings. In the present study, structural equation modeling was used to test these links. The results showed that perceptions of a performance climate were associated with ego orientation, whereas perceptions of a mastery climate were linked to task orientation. Furthermore, no significant links were found between task orientation and direction of competitive anxiety, while it was shown that the impact of ego orientation on the intensity and direction of cognitive and somatic anxiety was exerted through self-confidence. No significant direct links were found between motivational climates and competitive anxiety, thus implying that motivational climates may have an indirect impact on affective responses through the different goal orientations. The findings of the present study are discussed along with suggestions for examining situational and individual difference variables that may explain the relationships between intensity and direction of competitive anxiety and achievement goals and motivational climates.

Achievement↗
PubMed2005

Modeling climate change effects on the potential production of French plains forests at the sub-regional level.

We modeled the effects of climate change and two forest management scenarios on wood production and forest carbon balance in French forests using process-based models of forest growth. We combined data from the national forest inventory and soil network survey, which were aggregated over a 50 x 50-km grid, i.e., the spatial resolution of the climate scenario data. We predicted and analyzed the climate impact on potential forest production over the period 1960-2100. All models predicted a slight increase in potential forest yield until 2030-2050, followed by a plateau or a decline around 2070-2100, with overall, a greater increase in yield in northern France than in the south. Gross and net primary productivities were more negatively affected by soil water and atmospheric water vapor saturation deficits in western France because of a more pronounced shift in seasonal rainfall from summer to winter. The rotation-averaged values of carbon flux and production for different forest management options were estimated during four years (1980, 2015, 2045 and 2080). Predictions were made using a two-dimensional matrix covering the range of local soil and climate conditions. The changes in ecosystem fluxes and forest production were explained by the counterbalancing effect of rising CO2 concentration and increasing water deficit. The effect of climate change decreased with rotation length from short rotations with high production rates and low standing biomasses to long rotations with low productivities and greater standing biomasses. Climate effects on productivity, both negative and positive, were greatest on high fertility sites. Forest productivity in northern France was enhanced by climate change, increasingly from west to east, whereas in the southwestern Atlantic region, productivity was reduced by climate change to an increasing degree from west to east.

Biomass↗
PubMed2001

A framework to guide thinking and analysis regarding climate change policies.

The potential impacts from climate change, and climate change policies, are massive. Careful thinking about what we want climate change policies to achieve is a crucial first step for analysts to help governments make wise policy choices to address these concerns. This article presents an adaptive framework to help guide comparative analysis of climate change policies. The framework recognizes the inability to forecast long-term impacts (due in part to path dependance) as a constraint on the use of standard policy analysis, and stresses learning over time as a fundamental concern. The framework focuses on the objectives relevant for climate change policy in North America over the near term (e.g., the next 20 years). For planning and evaluating current climate policy alternatives, a combination of fundamental objectives for the near term and proxy objectives for characterizing the state of the climate problem and the ability to address it at the end of that term is suggested. Broad uses of the framework are discussed, along with some concrete examples. The framework is intended to provide a basis for policy analysis that explicitly considers the benefits of learning over time to improve climate change policies.

Journal Article↗
PubMed2006

Climate change and disaster management.

Climate change, although a natural phenomenon, is accelerated by human activities. Disaster policy response to climate change is dependent on a number of factors, such as readiness to accept the reality of climate change, institutions and capacity, as well as willingness to embed climate change risk assessment and management in development strategies. These conditions do not yet exist universally. A focus that neglects to enhance capacity-building and resilience as a prerequisite for managing climate change risks will, in all likelihood, do little to reduce vulnerability to those risks. Reducing vulnerability is a key aspect of reducing climate change risk. To do so requires a new approach to climate change risk and a change in institutional structures and relationships. A focus on development that neglects to enhance governance and resilience as a prerequisite for managing climate change risks will, in all likelihood, do little to reduce vulnerability to those risks.

Disaster Planning↗
PubMed2005

Eliciting information from experts on the likelihood of rapid climate change.

The threat of so-called rapid or abrupt climate change has generated considerable public interest because of its potentially significant impacts. The collapse of the North Atlantic Thermohaline Circulation or the West Antarctic Ice Sheet, for example, would have potentially catastrophic effects on temperatures and sea level, respectively. But how likely are such extreme climatic changes? Is it possible actually to estimate likelihoods? This article reviews the societal demand for the likelihoods of rapid or abrupt climate change, and different methods for estimating likelihoods: past experience, model simulation, or through the elicitation of expert judgments. The article describes a survey to estimate the likelihoods of two characterizations of rapid climate change, and explores the issues associated with such surveys and the value of information produced. The surveys were based on key scientists chosen for their expertise in the climate science of abrupt climate change. Most survey respondents ascribed low likelihoods to rapid climate change, due either to the collapse of the Thermohaline Circulation or increased positive feedbacks. In each case one assessment was an order of magnitude higher than the others. We explore a high rate of refusal to participate in this expert survey: many scientists prefer to rely on output from future climate model simulations.

Journal Article↗
PubMedDate not supplied

Global climate changes, natural disasters, and travel health risks.

Whether the result of cyclical atmospheric changes, anthropogenic activities, or combinations of both, authorities now agree that the earth is warming from a variety of climatic effects, including the cascading effects of greenhouse gas emissions to support human activities. To date, most reports of the public health outcomes of global warming have been anecdotal and retrospective in design and have focused on heat stroke deaths following heat waves, drowning deaths in floods and tsunamis, and mosquito-borne infectious disease outbreaks following tropical storms and cyclones. Accurate predictions of the true public health outcomes of global climate change are confounded by several effect modifiers including human acclimatization and adaptation, the contributions of natural climatic changes, and many conflicting atmospheric models of climate change. Nevertheless, temporal relationships between environmental factors and human health outcomes have been identified and may be used as criteria to judge the causality of associations between the human health outcomes of climate changes and climate-driven natural disasters. Travel medicine physicians are obligated to educate their patients about the known public health outcomes of climate changes, about the disease and injury risk factors their patients may face from climate-spawned natural disasters, and about the best preventive measures to reduce infectious diseases and injuries following natural disasters throughout the world.

Disasters↗
PubMed2004

Probabilistic integrated assessment of "dangerous" climate change.

Climate policy decisions are being made despite layers of uncertainty. Such decisions directly influence the potential for "dangerous anthropogenic interference with the climate system." We mapped a metric for this concept, based on Intergovernmental Panel on Climate Change assessment of climate impacts, onto probability distributions of future climate change produced from uncertainty in key parameters of the coupled social-natural system-climate sensitivity, climate damages, and discount rate. Analyses with a simple integrated assessment model found that, under midrange assumptions, endogenously calculated, optimal climate policy controls can reduce the probability of dangerous anthropogenic interference from approximately 45% under minimal controls to near zero.

Journal Article↗
PubMed2005

The effect of executive walk rounds on nurse safety climate attitudes: a randomized trial of clinical units[ISRCTN85147255] [corrected].

BACKGROUND: Executive walk rounds (EWRs) are a widely used but unstudied activity designed to improve safety culture in hospitals. Therefore, we measured the impact of EWRs on one important part of safety culture -- provider attitudes about the safety climate in the institution. METHODS: Randomized study of EWRs for 23 clinical units in a tertiary care teaching hospital. All providers except physicians participated. EWRs were conducted at each unit by one of six hospital executives once every four weeks for three visits. Providers were asked about their concerns regarding patient safety and what could be done to improve patient safety. Suggestions were tabulated and when possible, changes were made. Provider attitudes about safety climate measured by the Safety Climate Survey before and after EWRs. We report mean scores, percent positive scores (percentage of providers who responded four or higher on a five point scale (agree slightly or agree strongly), and the odds of EWR participants agreeing with individual survey items when compared to non-participants. RESULTS: Before EWRs the mean safety climate scores for nurses were similar in the control units and EWR units (78.97 and 76.78, P = 0.458) as were percent positive scores (64.6% positive and 61.1% positive). After EWRs the mean safety climate scores were not significantly different for all providers nor for nurses in the control units and EWR units (77.93 and 78.33, P = 0.854) and (56.5% positive and 62.7% positive). However, when analyzed by exposure to EWRs, nurses in the control group who did not participate in EWRs (n = 198) had lower safety climate scores than nurses in the intervention group who did participate in an EWR session (n = 85) (74.88 versus 81.01, P = 0.02; 52.5% positive versus 72.9% positive). Compared to nurses who did not participate, nurses in the experimental group who reported participating in EWRs also responded more favorably to a majority of items on the survey. CONCLUSION: EWRs have a positive effect on the safety climate attitudes of nurses who participate in the walk rounds sessions. EWRs are a promising tool to improve safety climate and the broader construct of safety culture.

Adult↗
PubMed2006

Spatio-temporal analysis of the role of climate in inter-annual variation of malaria incidence in Zimbabwe.

BACKGROUND: On the fringes of endemic zones climate is a major determinant of inter-annual variation in malaria incidence. Quantitative description of the space-time effect of this association has practical implications for the development of operational malaria early warning system (MEWS) and malaria control. We used Bayesian negative binomial models for spatio-temporal analysis of the relationship between annual malaria incidence and selected climatic covariates at a district level in Zimbabwe from 1988-1999. RESULTS: Considerable inter-annual variations were observed in the timing and intensity of malaria incidence. Annual mean values of average temperature, rainfall and vapour pressure were strong positive predictors of increased annual incidence whereas maximum and minimum temperature had the opposite effects. Our modelling approach adjusted for unmeasured space-time varying risk factors and showed that while year to year variation in malaria incidence is driven mainly by climate, the resultant spatial risk pattern may to large extent be influenced by other risk factors except during high and low risk years following the occurrence of extremely wet and dry conditions, respectively. CONCLUSION: Our model revealed a spatially varying risk pattern that is not attributable only to climate. We postulate that only years characterized by extreme climatic conditions may be important for developing climate based MEWS and for delineating areas prone to climate driven epidemics. However, the predictive value of climatic risk factors identified in this study still needs to be evaluated.

Bayes Theorem↗
PubMed2005

Assessment of nurses' work climate at Alexandria Main University Hospital.

Work climate is indicative of how well the organization is realizing its full potential. An accurate assessment of work climate can identify the unnecessary obstacles to nurses interfering with their best performance. The present study aims to assess nurses' work climate at Alexandria Main University Hospital. The study sample included all nurses (N=400) who were working in inpatient medical and surgical units at the Alexandria Main University Hospital who were available at the time of data collection. A structured questionnaire was developed to assess nurses' perceptions regarding the dimensions of work climate. Data was collected by individual interview using the structured questionnaire. Results indicated that the highest percentages of nurses in medical and surgical units perceived that their work climate is characterized by good way of performance management, feeling of responsibility, warmth and supportive relationships, quality of communication, morale, organizational clarity and feeling of identity and belongness to the hospital. Nurses perceived that they are lacking work climate conducive to conflict resolution, participation in decision making, opportunity for training and development, fair rewards and recognition, calculated risks, sufficient resources, effective leadership and teamwork. There were no significant difference between nurses perceptions in medical and surgical units regarding all dimensions of work climate. The highest percentage of nurses in all units were satisfied only with the feeling of responsibility, way of performance management, and quality of communication. Conflict and identity were perceived as the most important areas that need improvement in the hospital. Based on the results recommendations were given to enhance work climate through designing compensation and recognition systems, and negotiate their requirements and accomplishment based on established standards and outcomes measures. Also, encouragement of and planning for participative decision making, teamwork, in-service training program and open communication are recommended to be present in the work units.

Adult↗
PubMed2004

Regional climate shifts caused by gradual global cooling in the Pliocene epoch.

The Earth's climate has undergone a global transition over the past four million years, from warm conditions with global surface temperatures about 3 degrees C warmer than today, smaller ice sheets and higher sea levels to the current cooler conditions. Tectonic changes and their influence on ocean heat transport have been suggested as forcing factors for that transition, including the onset of significant Northern Hemisphere glaciation approximately 2.75 million years ago, but the ultimate causes for the climatic changes are still under debate. Here we compare climate records from high latitudes, subtropical regions and the tropics, indicating that the onset of large glacial/interglacial cycles did not coincide with a specific climate reorganization event at lower latitudes. The regional differences in the timing of cooling imply that global cooling was a gradual process, rather than the response to a single threshold or episodic event as previously suggested. We also find that high-latitude climate sensitivity to variations in solar heating increased gradually, culminating after cool tropical and subtropical upwelling conditions were established two million years ago. Our results suggest that mean low-latitude climate conditions can significantly influence global climate feedbacks.

Animals↗
PubMed2025

Harnessing Landscape Genomics to Evaluate Genomic Vulnerability and Future Climate Resilience in an East Asia Perennial.

In this era of rapid climate change, understanding the adaptive potential of organisms is imperative for buffering biodiversity loss. Genomic forecasting provides invaluable insights into population vulnerability and adaptive potential under diverse climatic conditions, thereby facilitating management interventions and bolstering shaping species-specific germplasm conservation strategies. We primarily employed landscape genomics approaches, leveraging single-nucleotide polymorphisms obtained through whole-genome resequencing of 201 individuals across 43 Rheum palmatum complex populations, to pinpoint adaptive variation and its significance in the context of future climates, delineate seed zones, and establish guidelines for ex situ germplasm conservation. The species complex exhibited strong signatures of local adaptation and differential genomic vulnerabilities across its distribution range, with eastern lineage populations facing significant maladaptation risks under future climate scenarios. Using diverse datasets of putatively adaptive loci and climate change scenarios, we delineated three distinct seed zones within the species' range, estimated varying sample sizes per zone to capture most adaptive diversity, and predicted shifts in seed zone centroids ranging from 48.3 to 359.3 km from historical distributions to mitigate climate change impacts. Collectively, our findings underscore the importance of integrating genomic and environmental data to forecast the adaptive trajectory of an East Asian perennial under anticipated climate changes, guide seed zone delineation for germplasm conservation and enhance population resilience. These results provide a blueprint for designing targeted conservation strategies and restoration plans in other imperilled species.

Climate Change↗