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Variations in leaf area index (LAI) are critical to research on forest ecosystem structure and function, especially carbon and water cycle, and their responses to climate change. Using the ensemble empirical mode decomposition (EEMD) method and global inventory modeling and mapping studies (GIMMS) LAI3g dataset from 1982 to 2010, we analyzed the nonlinear feature and spatial difference of forest LAI variability over China for the past 29 years in this paper. Results indicated that the national-averaged forest LAI was characterized by quasi-3- and quasi-7-year oscillations, which generally exhibited a rising trend with an increasing rate. When compared with 1982, forest LAI change by 2010 was more evident than that by 1990 and 2000. The largest increment of forest LAI occurred in Central and South China, while along the southeastern coastal areas LAI increased at the fastest pace. During the study period, forest LAI experienced from decrease to increase or vice versa across much of China and varied monotonically for only a few areas. Focusing on regional-averaged trend processes, almost all eco-geographical regions showed continuously increasing trends in forest LAI with different magnitudes and speeds, other than tropical humid region and temperate humid/subhumid region, where LAI decreased initially and increased afterwards. [ABSTRACT FROM AUTHOR]

The impact of climatic changes on life cycles by re-scheduling the timing of reproduction is an important topic in studies of biodiversity. Global warming causes and will probably cause in the future not only raising temperatures but also an increasing frequency of extreme weather events. In 2013, the winter in central and north Europe ended late, with low temperatures and long-retained snow cover-this extreme weather phenomenon acted in opposition to the increasing temperature trend. In 2013, thermal conditions measured by the warmth sum in the period 15 March-15 April, a critical time for early breeding passerines, went far beyond the range of the warmth sums for at least 40 preceding years. Regardless of what was the reason for the extreme early spring 2013 and assuming that there is a potential for more atypical years because of climate change, we should look closely at every extreme phenomenon and its consequences for the phenology of organisms. In this paper, we report that the prolonged occurrence of winter conditions during the time that is crucial for Blue Tit ( Cyanistes caeruleus) and Great Tit ( Parus major) reproduction caused a substantial delay in the onset of egg laying in comparison with typical springs. [ABSTRACT FROM AUTHOR]

The Murray dairy region produces approximately 1.85 billion litres of milk each year, representing about 20 % of Australia's total annual milk production. An ongoing production challenge in this region is the management of the impacts of heat stress during spring and summer. An increase in the frequency and severity of extreme temperature events due to climate change may result in additional heat stress and production losses. This paper assesses the changing nature of heat stress now, and into the future, using historical data and climate change projections for the region using the temperature humidity index (THI). Projected temperature and relative humidity changes from two global climate models (GCMs), CSIRO MK3.5 and CCR-MIROC-H, have been used to calculate THI values for 2025 and 2050, and summarized as mean occurrence of, and mean length of consecutive high heat stress periods. The future climate scenarios explored show that by 2025 an additional 12-15 days (compared to 1971 to 2000 baseline data) of moderate to severe heat stress are likely across much of the study region. By 2050, larger increases in severity and occurrence of heat stress are likely (i.e. an additional 31-42 moderate to severe heat stress days compared with baseline data). This increasing trend will have a negative impact on milk production among dairy cattle in the region. The results from this study provide useful insights on the trends in THI in the region. Dairy farmers and the dairy industry could use these results to devise and prioritise adaptation options to deal with projected increases in heat stress frequency and severity. [ABSTRACT FROM AUTHOR]

Abstract  Previous assessments of the impacts of climate change on heat-related mortality use the “delta method” to create temperature projection time series that are applied to temperature–mortality models to estimate future mortality impacts. The delta method means that climate model bias in the modelled present does not influence the temperature projection time series and impacts. However, the delta method assumes that climate change will result only in a change in the mean temperature but there is evidence that there will also be changes in the variability of temperature with climate change. The aim of this paper is to demonstrate the importance of considering changes in temperature variability with climate change in impacts assessments of future heat-related mortality. We investigate future heat-related mortality impacts in six cities (Boston, Budapest, Dallas, Lisbon, London and Sydney) by applying temperature projections from the UK Meteorological Office HadCM3 climate model to the temperature–mortality models constructed and validated in Part 1. We investigate the impacts for four cases based on various combinations of mean and variability changes in temperature with climate change. The results demonstrate that higher mortality is attributed to increases in the mean and variability of temperature with climate change rather than with the change in mean temperature alone. This has implications for interpreting existing impacts estimates that have used the delta method. We present a novel method for the creation of temperature projection time series that includes changes in the mean and variability of temperature with climate change and is not influenced by climate model bias in the modelled present. The method should be useful for future impacts assessments. Few studies consider the implications that the limitations of the climate model may have on the heat-related mortality impacts. Here, we demonstrate the importance of considering this by conducting an evaluation of the daily and extreme temperatures from HadCM3, which demonstrates that the estimates of future heat-related mortality for Dallas and Lisbon may be overestimated due to positive climate model bias. Likewise, estimates for Boston and London may be underestimated due to negative climate model bias. Finally, we briefly consider uncertainties in the impacts associated with greenhouse gas emissions and acclimatisation. The uncertainties in the mortality impacts due to different emissions scenarios of greenhouse gases in the future varied considerably by location. Allowing for acclimatisation to an extra 2°C in mean temperatures reduced future heat-related mortality by approximately half that of no acclimatisation in each city. [ABSTRACT FROM AUTHOR]

Abstract  This paper is a portrayal of aspects of weather and climate as front-page news in Europe’s rainiest city, Bergen, Norway. It descriptively explores the coverage and different contextualization of weather and climate. By asking the simple question of what actually constitutes a good or bad weather day in Bergen, short-lived weather descriptions in the news are compared with climatological data. The study reveals a complex picture with different annotations of good and bad weather depending on the season. It is found that, while the amount of sunshine is important for defining a good weather day during winter, it is temperature that determines a good summer day. In spring, holidays and the anticipation of the summer result in a lower sunshine threshold for what to call a good weather day. The conspicuousness of rainfall is shown by both the number of articles and the various contexts in which bad weather is presented in the newspaper. It is suggested here that it is not the amount of rainfall that creates headlines, but rather the context of the surrounding event, as well as the weather of the previous period. Human perceptions cannot be read off meteorological stations. Nevertheless, they can strengthen measurements and, therefore, have a value in themselves. As a result, perceptions of seasonal or daily weather anomalies may well play a role in how society in Bergen will think about and experience a probable climate change with a projected increase in rainfall. [ABSTRACT FROM AUTHOR]

The spawning and well-being of fish in an ecosystem are closely linked to climatic cues, viz., temperature and rainfall. Reduced fitness can affect the reproductive performance and lead to skipped spawning. Benchmarking the threshold fitness required for a fish population to achieve readiness for spawning, and understanding how climatic parameters influence the fitness will aid in predicting the fate of its reproductive success in future climatic conditions. This study determined the threshold condition factor pre-spawning fitness (Kspawn50) at which 50% of the female Channa punctata population can be deemed fit for spawning. The optimal climate within which pre-spawning fitness is attained by this species under Indian climatic conditions was also identified. The study was conducted from June 2015 to September 2016, covering two spawning seasons (June–August) in a Gangetic floodplain wetland of West Bengal, India. The non-parametric Kaplan–Meier method (survival fit) was used for estimation of pre-spawning fitness. "Ready to spawn" females were classified based on binary coding of the gonadal maturity stages. The thermal and precipitation range within which spawning fitness is achieved was identified by using the locally weighted smoothing technique. Female C. punctata pre-spawning fitness (Kspawn50) ranged from 1.26 to 1.39 with an estimated median of 1.29 units. Temperatures between 29 and 32 °C and rainfall above 100 mm were conducive to attaining the requisite pre-spawning fitness in C. punctata. This is the first study benchmarking the pre-spawning fitness and optimal climate for C. punctata. Understanding spawning requirements can inform the climate change–induced impacts on reproductive plasticity and evolutionary adaptations of snakeheads in the Ganga river basin. [ABSTRACT FROM AUTHOR]

Anthropogenic warming's effects on phenology across environmental and temporal gradients are well recognized. Long-term phenological monitoring data are often limited in duration and geographic scope, but recent efforts to digitize herbaria collections make it possible to reliably reconstruct historic flowering phenology across broad geographic scales and multiple species, lending to an increased understanding of community response to climate change. In this study, we examined collection dates (1901 to 2015) of 8540 flowering specimens from 39 native species in the Pacific Northwest (PNW) region of North America. We hypothesized that flowering phenology would be sensitive to temperature but that sensitivity would vary depending on blooming season and geographic range position. As expected, we found that early-season bloomers are more sensitive to temperature than later-season bloomers. Sensitivity to temperature was significantly greater at low elevations and in the maritime (western) portion of the PNW than at higher elevations and in the eastern interior, respectively. The elevational and longitudinal effects on flowering sensitivity reflect spring "arriving" earlier at low elevations and in the maritime portion of the PNW. These results demonstrate that phenological responses to warming vary substantially across climatically diverse regions, warranting careful and nuanced consideration of climate warming's effects on plant phenology. [ABSTRACT FROM AUTHOR]

The history of climate is crucially important for any part of the world to understand the nature of climate change. In this context, precipitation reconstruction is still lacking in northern Kazakhstan. The purpose of this study is to present a reconstruction for the total precipitation of October of the previous year to July of the current year in northern Kazakhstan. Pinus sylvestris L. (Scots pine) forests in Burabai Region are quite important to collect samples to study the climate history. A regional chronology, covering the years of 1702–2014 of Pinus sylvestris constructed by using 289/466 trees/cores was used in the reconstruction. The gridded climate data for the years of 1950–2014 were used in the calibration and verification process. High and significant correlations were obtained between tree-ring widths and October to July precipitation in Burabai Region. Based on this significant relationship, reconstruction was performed for the years of 1744–2014. Adjusted R2, F-value, sign test, and r value were found as 0.38, 39.7 (P ≤ 0.001), 47+/17, and 0.62 for reconstruction, respectively. The reconstruction showed that 43 dry and 42 wet years occurred during the years of 1744–2014. Only a one-time four-year duration of the wet period was determined covering the years 1978–1981. However, three of six very dry years occurred after the 1950s. As a conclusion, extremity in recent decades is getting an increase in Burabai region. [ABSTRACT FROM AUTHOR]

This study investigated impacts of climate variability on mosquito survival at Obafemi Awolowo University Campus, Ile-Ife, south-western Nigeria, and determined the regional climate suitability level for malaria transmission between 1996 and 2015. It employed some established climate-dependent models to simulate daily mosquito survival probabilities, p and a fuzzy logic suitability (FLS) model to determine the suitability conditions for malaria transmission across seasons. Multivariate regression analysis and lag correlation up to 4 months were performed to examine contributions of climate variation to the reported malaria cases. Results revealed that mosquitoes could survive all-year round with p values ranging between 0.40 and 0.96 under the prevailing mean climate. However, the climate suitability level for transmission of malaria was 'moderate' (0.45 < p ≤ 0.60) in the dry season but 'very high' (0.75 < p ≤ 0.96) in the wet. Rainfall was found to be the best predictor (r = 0.7, R2 = 0.448, p < 0.05) and no significant time-delay effect was noticed between climatic variables and malaria occurrence except for wind speed at 1-month lag. About 61% (multiple R2= 0.613 at p = 0.1) of monthly variations in reported malaria cases were accounted for by climate variability. Further probe revealed that non-climatic factors such as behavioural and socio-cultural status of the students' population played a very important role in malaria transmission and occurrence. The findings suggested that effective malaria control and interventions must integrate the crucial roles of both climatic and non-climatic factors in the study area. [ABSTRACT FROM AUTHOR]

Vegetation growth and phenology are largely regulated by base temperature (Tb) and thermal accumulation. Hence, the growing degree-days (GDD) and growing season (GS) calculated based on Tb have primary effects on terrestrial ecosystems, and could be changed by the significant warming during the last century. By choosing 0, 5, and 10 °C, three key Tb for vegetation growth, the GDD and GS in China during 1960–2011 were developed based on 536 meteorological stations with homogenized daily mean temperatures. Results show that both the GDD and GS showed positive sensitivity to the annual mean temperature. The start of the growing season (SOS) has advanced by 4.86–6.71 days, and the end of the growing season (EOS) has been delayed by 4.32–6.19 days, lengthening the GS by 10.76–11.02 days in China as a whole during 1960–2011, depending on the Tb chosen. Consistently, the GDD has totally increased 218.92–339.40 °C days during the 52 years, with trends more pronounced in those based on a lower Tb. The GDD increase was significant (Mann–Kendall test, p < 0.01) over China except for the north of Southwest China, while the significant GS extension only scattered over China. Whereas the extensions of GS0 and GS5 were dominated by the advance in SOS, the GS10 extension was closely linked to the delay in EOS. Regionally, the GS extension in the eastern monsoon zone and northwest arid/semi-arid zone was driven by the advance in SOS and delay in EOS, respectively. Moreover, each variation has a substantial acceleration mostly in 1987 or 1996, and a speed reduction or even a trend reversal in the early 2000s. Changes in the thermal growing degree-days and season are expected to have great implications for biological phenology, agricultural production, and terrestrial carbon cycle in the future. [ABSTRACT FROM AUTHOR]

Global warming is considered as a phenomenon having a negative effect on animals living in cold climate. However, herbivorous species inhabiting cold zones may potentially benefit from increase of temperature as this influence duration of vegetation period and increase food resources. In this study, we analyze the impact of climate factors on the long-term dynamics of an isolated and unhunted population of the Tatra chamois Rupicapra rupicapra tatrica. The population growth rate, based on autumnal chamois counting carried out from 1957 to 2016, were correlated with a set of climatic variables. We tested the hypothesis that high temperatures in summer could have a positive impact on the population, since they influence vegetation growth, which ensure food resources. On the other hand, heavy falls of snow and long-lasting and deep snow cover could adversely affect the population by reducing population survival during the winter. The results of this study indicate that climatic variables best explaining the autoregressed population growth rate (from the autumn of year t-1 to the autumn of year t) were the mean summer temperature of year t-1: the population increase was greater following a warmer summer in year t-1 and, in lower extent, the total precipitation during winter: the population decrease was greater following a winter with heavy snowfall. Duration and thickness of snow cover have no negative effect on population growth rate. The results indicate that the population dynamic of the Tatra chamois is determined in the long term by weather conditions, mainly by temperature, when kids are birthing and growing. The results of this work highlight that climatic changes may be responsible for the population dynamic of high-mountain species. Climate warming may lead to increase in duration of vegetation period in cold climatic zones, what may in turn have positive effect on herbivorous species, which relay upon food resources limited by low temperatures within vegetation period. [ABSTRACT FROM AUTHOR]

Variation in ambient temperature affects various life stages of organisms. It has been suggested that climate change not only implies higher global temperatures but also more unpredictable weather and more frequent extreme weather events. Temperature has a major influence on the optimal laying-incubation-hatching dates of insectivorous passerines, because it poses energetic constraints and affects the timing of food abundance. We have been studying breeding characteristics of great tits Parus major and blue tits Cyanistes caeruleus in two areas, an urban parkland and a deciduous forest, around the city of Łódź since 2002. During the egg-laying period in 2017, both tit species at both study areas faced an unusual cold spell as reflected by a sudden decrease in the mean ambient temperature to ca. 2-3 °C for about 5 days, which caused mean hatching delays of up to 6 days. Since flexibility of behavior plays a major role in adjusting to unpredictable weather conditions, examining its limits may be an important goal for future research. [ABSTRACT FROM AUTHOR]

A national biodiversity and climate change adaptation plan is being developed for Ireland by the Department of Communications, Climate Action, and Environment. In order to inform such a plan, it was necessary to review and synthesize some of the recent literature pertaining to the impact of climate change on biodiversity in Ireland. Published research on this topic fell within three broad categories: (i) changes in the timing of life-cycle events (phenology) of plants, birds, and insects; (ii) changes in the geographic range of some bird species; and (iii) changes in the suitable climatic zones of key habitats and species. The synthesis revealed evidence of (i) a trend towards earlier spring activity of plants, birds, and insects which may result in a change in ecosystem function; (ii) an increase in the number of bird species; and (iii) both increases and decreases in the suitable climatic area of key habitats and species, all of which are expected to impact Ireland’s future biodiversity. This process identified data gaps and limitations in available information both of which could be used to inform a focused research strategy. In addition, it raises awareness of the potential implications of climate change for biodiversity in Ireland and elsewhere and demonstrates the need for biodiversity conservation plans to factor climate change into future designs. [ABSTRACT FROM AUTHOR]

The Executive Board of the International Society of Biometeorology (ISB) founded the Commission on Climate, Tourism and Recreation (CCTR) at the 15th International Congress of Biometeorology in Sydney, Australia in 1999. The aims of the CCTR are to bring together researchers from around the world to critically review the current state of knowledge in tourism and recreation climatology and explore possibilities for future research. Almost two decades on, research in tourism climatology has developed and expanded due in large part to the initiatives and activities of the CCTR and several collaborative research projects run under the auspices of the CCTR. This work is reviewed here. Recent CCTR meeting highlighted the fact that, although climate is an essential part of the resource base for tourism, which is one of the world's biggest and fastest growing industries, relatively little is known about the effects of climate on tourist choices and broad demand patterns or the influence climate has on the commercial prospects and sustainability of tourism operators and destinations. The work here reviews what has been done, its conceptual underpinnings and current research frontiers. [ABSTRACT FROM AUTHOR]

Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival. [ABSTRACT FROM AUTHOR]

Models that predict the timing of deciduous tree leaf emergence are typically very sensitive to temperature. However, many temperature data products, including those from climate models, have been developed at a very coarse spatial resolution. Such coarse-resolution temperature products can lead to highly biased predictions of leaf emergence. This study investigates how dynamical downscaling of climate models impacts simulations of deciduous tree leaf emergence in California. Models for leaf emergence are forced with temperatures simulated by a general circulation model (GCM) at ~200-km resolution for 1981-2000 and 2031-2050 conditions. GCM simulations are then dynamically downscaled to 32- and 8-km resolution, and leaf emergence is again simulated. For 1981-2000, the regional average leaf emergence date is 30.8 days earlier in 32-km simulations than in ~200-km simulations. Differences between the 32 and 8 km simulations are small and mostly local. The impact of downscaling from 200 to 8 km is ~15 % smaller in 2031-2050 than in 1981-2000, indicating that the impacts of downscaling are unlikely to be stationary. [ABSTRACT FROM AUTHOR]

The impact of climate change on crop yield is compounded by cultivar shifts and agronomic management practices. To determine the relative contributions of climate change, cultivar shift, and management practice to changes in maize ( Zea mays L.) yield in the past three decades, detailed field data for 1981-2009 from four representative experimental stations in North China Plain (NCP) were analyzed via model simulation. The four representative experimental stations are geographically and climatologically different, represent the typical cropping system in the study area, and have more complete weather/crop records for the period of 1981-2009. The results showed that while the shift from traditional to modern cultivar increased yield by 23.9-40.3 %, new fertilizer management increased yield by 3.3-8.6 %. However, the trends in climate variables for 1981-2009 reduced maize yield by 15-30 % in the study area. Among the main climate variables, solar radiation had the largest effect on maize yield, followed by temperature and then precipitation. While a significant decline in solar radiation in 1981-2009 (maybe due to air pollution) reduced yield by 12-24 %, a significant increase in temperature reduced yield by 3-9 %. In contrast, a non-significant increase in precipitation during the maize growth period increased yield by 0.9-3 % at three of the four investigated stations. However, a decline in precipitation reduced yield by 3 % in the remaining station. The study revealed that although the shift from traditional to modern cultivars and agronomic management practices contributed most to the increase in maize yield, the negative impact of climate change was large enough to offset 46-67 % of the trend in the observed yields in the past three decades in NCP. The reduction in solar radiation, especially in the most critical period of maize growth, limited the process of photosynthesis and thereby further reduced maize yield. [ABSTRACT FROM AUTHOR]

The goal of this research is to transpose the unprecedented 2003 European excessive heat event to six Korean cities and to develop meteorological analogs for each. Since this heat episode is not a model but an actual event, we can use a plausible analog to assess the risk of increasing heat on these cities instead of an analog that is dependent on general circulation (GCM) modeling or the development of arbitrary scenarios. Initially, the 2003 summer meteorological conditions from Paris are characterized statistically and these characteristics are transferred to the Korean cites. Next, the new meteorological dataset for each Korean city is converted into a daily air mass calendar. We can then determine the frequency and character of 'offensive' air masses in the Korean cities that are historically associated with elevated heat-related mortality. One unexpected result is the comparative severity of the very hot summer of 1994 in Korea, which actually eclipsed the 2003 analog. The persistence of the offensive air masses is considerably greater for the summer of 1994, as were dew point temperatures for a majority of the Korean cities. For all the Korean cities but one, the summer of 1994 is associated with more heat-related deaths than the analog summer, in some cases yielding a sixfold increase over deaths in an average summer. The Korean cities appear less sensitive to heat-related mortality problems during very hot summers than do large eastern and Midwestern US cities, possibly due to a lesser summer climate variation and efficient social services available during extreme heat episodes. [ABSTRACT FROM AUTHOR]

Climate projection data were applied to two commonly used pome fruit flowering models to investigate potential differences in predicted full bloom timing. The two methods, fixed thermal time and sequential chill-growth, produced different results for seven apple and pear varieties at two Australian locations. The fixed thermal time model predicted incremental advancement of full bloom, while results were mixed from the sequential chill-growth model. To further investigate how the sequential chill-growth model reacts under climate perturbed conditions, four simulations were created to represent a wider range of species physiological requirements. These were applied to five Australian locations covering varied climates. Lengthening of the chill period and contraction of the growth period was common to most results. The relative dominance of the chill or growth component tended to predict whether full bloom advanced, remained similar or was delayed with climate warming. The simplistic structure of the fixed thermal time model and the exclusion of winter chill conditions in this method indicate it is unlikely to be suitable for projection analyses. The sequential chill-growth model includes greater complexity; however, reservations in using this model for impact analyses remain. The results demonstrate that appropriate representation of physiological processes is essential to adequately predict changes to full bloom under climate perturbed conditions with greater model development needed. [ABSTRACT FROM AUTHOR]

Most trees from temperate climates require the accumulation of winter chill and subsequent heat during their dormant phase to resume growth and initiate flowering in the following spring. Global warming could reduce chill and hence hamper the cultivation of high-chill species such as cherries. Yet determining chilling and heat requirements requires large-scale controlled-forcing experiments, and estimates are thus often unavailable. Where long-term phenology datasets exist, partial least squares (PLS) regression can be used as an alternative, to determine climatic requirements statistically. Bloom dates of cherry cv. 'Schneiders späte Knorpelkirsche' trees in Klein-Altendorf, Germany, from 24 growing seasons were correlated with 11-day running means of daily mean temperature. Based on the output of the PLS regression, five candidate chilling periods ranging in length from 17 to 102 days, and one forcing phase of 66 days were delineated. Among three common chill models used to quantify chill, the Dynamic Model showed the lowest variation in chill, indicating that it may be more accurate than the Utah and Chilling Hours Models. Based on the longest candidate chilling phase with the earliest starting date, cv. 'Schneiders späte Knorpelkirsche' cherries at Bonn exhibited a chilling requirement of 68.6 ± 5.7 chill portions (or 1,375 ± 178 chilling hours or 1,410 ± 238 Utah chill units) and a heat requirement of 3,473 ± 1,236 growing degree hours. Closer investigation of the distinct chilling phases detected by PLS regression could contribute to our understanding of dormancy processes and thus help fruit and nut growers identify suitable tree cultivars for a future in which static climatic conditions can no longer be assumed. All procedures used in this study were bundled in an R package ('chillR') and are provided as Supplementary materials. The procedure was also applied to leaf emergence dates of walnut (cv. 'Payne') at Davis, California. [ABSTRACT FROM AUTHOR]

Increases in temperature as a result of anthropogenically generated greenhouse gas (GHG) emissions are likely to impact key aspects of horticultural production. The potential effect of higher temperatures on fruit and nut trees' ability to break winter dormancy, which requires exposure to winter chilling temperatures, was considered. Three chill models (the 0-7.2°C, Modified Utah, and Dynamic models) were used to investigate changes in chill accumulation at 13 sites across Australia according to localised temperature change related to 1, 2 and 3°C increases in global average temperatures. This methodology avoids reliance on outcomes of future GHG emission pathways, which vary and are likely to change. Regional impacts and rates of decline in chilling differ among the chill models, with the 0-7.2°C model indicating the greatest reduction and the Dynamic model the slowest rate of decline. Elevated and high latitude eastern Australian sites were the least affected while the three more maritime, less elevated Western Australian locations were shown to bear the greatest impact from future warming. [ABSTRACT FROM AUTHOR]

The aim of this study was to select a phenological model that is able to calculate the beginning of egg laying of Great Tit ( Parus major) for both current and future climate conditions. Four models (M1-M4) were optimised on long-term phenological observations from the Ecological Research Centre Schlüchtern (Hessen/Germany). Model M1 was a common thermal time model that accumulates growing degree days (GDD) on an optimised starting date t. Since egg laying of Great Tit is influenced not only by air temperature but also by photoperiod, model M1 was extended by a daylength term to give M2. The other two models, M3 and M4, correspond to M1 and M2, but t was intentionally set to 1 January, in order to consider already rising temperatures at the beginning of the year. A comparison of the four models led to following results: model M1 had a relatively high root mean square error at verification (RMSE) of more than 4 days and can be used only to calculate the start of egg laying for current climate conditions because of the relatively late starting date for GDD calculation. The model failed completely if the starting date was set to 1 January (M3). Consideration of a daylength term in models M2 and M4 improved the performance of both models strongly (RMSE of only 3 days or less), increased the credibility of parameter estimation, and was a precondition to calculate reliable projections in the timing of egg laying in birds for the future. These results confirm that the start of egg laying of Great Tit is influenced not only by air temperature, but also by photoperiod. Although models M2 and M4 both provide comparably good results for current climate conditions, we recommend model M4-with a starting date of temperature accumulation on 1 January-for calculating possible future shifts in the commencement of egg laying. Our regional projections in the start of egg laying, based on five regional climate models (RCMs: REMO-UBA, ECHAM5-CLM, HadCM3-CLM, WETTREG-0, WETTREG-1, GHG emission scenario A1B), indicate that in the near future (2011-2040) no significant change will take place. However, in the mid- (2041-2070) and long-term (2071-2100) range the beginning of egg laying could be advanced significantly by up to 11 days on average of all five RCMs. This result corresponds to the already observed shift in the timing of egg laying by about 1 week, due mainly to an abrupt increase in air temperature at the end of the 1980s by 1.2 K between April and May. The use of five regional climate scenarios additionally allowed to estimate uncertainties among the RCMs. [ABSTRACT FROM AUTHOR]

Abstract  Data series for bud burst, beginning of flowering and petal fall for 20 species of deciduous trees and conifers at four sites in different regions of southern Norway have been analysed and related to temperature series. On average, the spring phenophases occurred 7 days earlier during the period 1971–2005. The most significant linear trends were observed for the earliest phases. The trends in this period were compared with trends in other periods, the longest one starting in 1927. Those starting in cold decades and ending in 2005 were in most instances statistically significant, whereas hardly any significant trend appeared for series starting in warm decades. This fact showed that the results of trend studies are very sensitive to the choice of starting year. There were significant decadal variations in 40% of the series. The dates of occurrence of the phenophases, varying from the first days of May to the first days of June, correlated with seasonal temperature series, in most cases strongest to mean temperatures for the seasons March–May and April–May. The North Atlantic Oscillation Index (NAOI) for January and February appeared to have some predictive power for the date of occurrence of the recorded phases. The basis for this may be that the oscillations described by the index are of importance for the fulfilment of physiological chilling requirements needed to break bud dormancy. The same genotypes of the trees were grown in region West Norway and in Central Norwegian region; during the period 1965–2005 the trends towards earlier bud burst were more pronounced and steeper at the western site. [ABSTRACT FROM AUTHOR]

Abstract  The purpose of this research was to explore the latent dimensions that underlie people’s use of adjectives that can describe weather and climate conditions. A sample of 1,011 university undergraduate students residing the southeastern United States evaluated the weather and climate of that region using 143 English language adjectives. Data were collected over a two-year period during various weather and seasonally related climatic conditions. Polychoric correlations among the adjective ratings were calculated; the matrix of correlations was factor analyzed. Twelve underlying factors related to weather and climate perceptions were observed: 1. threatening, severe, violent, 2. dismal, drab, dark, 3. cold and wintry, 4. hot and summery, 5. tranquil and pleasant, 6. stormy and wet, 7. bright and clear, 8. blowing and blustery, 9. damp and moist, 10. cloudy and cool, 11. predictable and unchanging, and 12. hazy and dusty. A second-order factor analysis revealed two factors pertaining to weather valence: 1. bad or extreme and 2. good or routine conditions. The study results were noteworthy in revealing some of the basic linguistic dimensions along which people perceive and experience weather and climate at the current time in the southeastern United States. The study also represents the use of a new technique for biometeorologists to use in assessing climate perceptions in culturally and climatically diverse regions. [ABSTRACT FROM AUTHOR]