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© Author(s) 2014. CC Attribution 3.0 License. The proposal for this special issue has been initiated within the CIRCE (EU-fp6 project, contract number 036961) and supported by the MedCLIVAR network (www.medclivar.eu)., There is an increasing interest of scientists on climate extremes. A progressively larger number of papers dealing with climate issues have been produced in the past 15 yr, and those dealing with extremes have increased at an even faster pace. The number of papers on extremes in the Mediterranean follows this overall trend and confirms how extremes are perceived to be important by the scientific community and by society. This special issue (which is mainly related to activities of the MedCLIVAR (Mediterranean CLImate VARiability and Predictability) and CIRCE (Climate Change and Impact Research: the Mediterranean Environment) projects), contains thirteen papers that are representative of current research on extremes in the Mediterranean region. Five have precipitation as its main target, four temperature (one paper addresses both variables), and two droughts; the remaining papers consider sea level, winds and impacts on society. Results are quite clear concerning climate evolution toward progressively hotter temperature extremes, but more controversial for precipitation, though in the published literature there are indications for a future increasing intensity of hydrological extremes (intense precipitation events and droughts). Scenario simulations suggest an attenuation of extreme storms, winds, waves and surges, but more results are requested for confirming this future change., MedCLIVAR Project (Mediterranean Climate Variability and Predictability), Unión Europea (UE), CIRCE (Climate change and impact research project), UE, Sixth Framework Programme (FP6), UE, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

The Antarctic Peninsula (AP) is a climate change hotspot, in which any alterations to the atmospheric circulation can lead to significant impacts on the cryosphere. Even though substantial evidence has been found on the effects of human-related greenhouse gas emissions on the climate of the AP, less studies have analyzed the effect of variations in stratospheric ozone concentrations on the regional climate, and that is the focus of this paper. Results show significant links between the concentration of stratospheric ozone and the regional circulation, as well as with variations on the frequency and intensity of cold air snaps east of the AP. Significant relationships are found between changes in ozone concentrations and minimum/maximum temperature distributions over AP weather stations over most of the seasons. A strong link is also found with the location, depth and intensity of the Amundsen Sea Low west of the AP, which is in most cases responsible for the temperature anomalies identified in this study., The authors would like to thank the anonymous reviewer and the Editor whose comments and suggestions helped to improve the paper. The research leading to this article was partly funded by Grant PICT2020-SerieA-03172 from the Agencia Nacional de Promoción de la Investigación, el Desarrollo Tecnológico y la Innovación (Ministry of Science and Technology of Argentina) to the University of Buenos Aires. The authors would like to acknowledge François Massonnet and Kyle Clem for fruitful discussions on an earlier version of this manuscript, as well as the European Centre for Medium-Range Weather Forecasts (ECMWF) for constructing and making available the ERA-5489 reanalysis dataset., Peer Reviewed, Postprint (author's final draft)

Climate change is pushing organisms closer to their physiological limits. Animals can reduce heat exposure – and the associated risks of lethal hyperthermia and dehydration – by retreating into thermal refuges. Refuge use nonetheless reduces foraging and reproductive activities, and thereby potentially fitness. Behavioural responses to heat thus define the selection pressures to which individuals are exposed. However, whether and why such behavioural responses vary between individuals remains largely unknown. Here, we tested whether early-life experience generates inter-individual differences in behavioural responses to heat at adulthood. In the arid-adapted zebra finch, parents incubating at high temperatures emit “heat-calls,” which adaptively alter offspring growth. We experimentally manipulated individual early life acoustic and thermal experience. At adulthood, across two summers, we then repeatedly recorded individual panting behaviour, microsite use, activity (N = 2,402 observations for 184 birds), and (for a small subset, N = 23 birds) body temperature, over a gradient of air temperatures (26–38°C), in outdoor aviaries. We found consistent inter-individual variation in behavioural thermoregulation, and show for the first time in endotherms that early-life experience contributes to such variation. Birds exposed prenatally to heat-calls started panting at lower temperatures than controls but panted less at high temperatures. It is possible that this corresponds to a heat-regulation strategy to improve water saving at high temperature extremes, and/or, allow maintaining high activity levels, since heat-call birds were also more active across the temperature gradient. In addition, microsite use varied with the interaction between early acoustic and thermal experiences, control-call birds from cooler nests using the cooler microsite more than their hot-nest counterpart

In this project warm extreme temperature events in the Arctic region during the spring months March, April and May were identified and analysed. In the analysis daily average NCEP reanalysis data from NOAA/OAR/ESRL PSL format was used. The extreme events were retrieved as the highest positive temperature anomalies from the climatological mean, and the synoptic scale plots for the 50 most extreme events were created to identify what patterns caused the extreme warming over the Polar region. By contouring the areas of statistical significance, the regions with a reoccuring pattern were identified. The results conclude that cyclonic activity over the high Arctic extending down over Greenland and northern Canada combined with anomalously high geopotential height over the north Pacific ocean, over the Arctic, and towards Siberia cause the high temperatures over the pole. A weaker Polar Vortex causes perturbations in the jet stream, ridges in these Rossby waves can act as a pathway for warm and moist air from the oceanic regions which has a warming effect in the Arctic. Further analysis can be done to investigate what teleconnections these spring-time extreme events have on a global scale., Under detta projekt har extremt varma temperaturevent i Arktisområdet under vårmånaderna Mars, April och Maj identifierats samt analyserats, genom att använda daglig medelvärdes NCEP reanalys data från NOAA/OAR/ESRL PSL i NetCDF format. De extrema händelserna identifierades genom att ta de största positiva temperaturavvikelserna från ett klimatologiskt medelvärde, storskaliga avvikelseplottar skapades för de 50 mest extrema händelserna för att kunna identifiera meteorologiska mönster som ovanligt varma Arktisdagar. De områden med mest återkommande mönsterna var statistiskt signifikanta och markerades med svarta konturer. Resultaten visar att lågtrycksaktivitet i Arktis som sträcker sig ner över Grönland samt norra Kanada kombinerat med höga geopotentialhöjdavvikelser över Stilla havet och Sibirien som sträcker sig upp mot Nordpolen orsakar ovanligt höga temperaturer i Arktis. En svag polarvirvel orsakar störningar i jetströmmen, dessa ryggar i jetströmmen kan transportera varm fuktig luft från haven mot polen vilket kan ha en värmande effekt. Vidare forskning kan utföras för att identifiera de exakta kopplingarna och konsekvenserna som dessa varma extrema Arktishändelser har globalt.

Temperature extremes have a crucial impact on agricultural, economic, health and energy sectors due to the occurrence of climate extreme events such as heat waves and cold waves. Limpopo province is among the hottest provinces of South Africa and experiences little rainfall which affect the water availabil ity, food production and biodiversity. In the Limpopo province, temperature extremes are expected to become more frequent as a result of climate change. The aim of this study was to model temperature extremes in the Limpopo province of South Africa using extreme value theory (EVT). The stationarity of the data was tested using augmented Dickey-Fuller (ADF), Phillips-Peron (PP) and Kwiatkowski-Phillips-Schmit-Shin (KPSS). Four candidate parent distri butions: normal, log-normal, gamma and Weibull distributions, were fitted to the average monthly maximum and minimum daily temperatures. Prior to the selection of the parent distributions, the data set at each station was subjected to normality test using the Shapiro-Wilk (SW) and Jarque-Bera (JB) tests. The stationarity and normality tests revealed that the maximum and minimum temperature data series at all the stations are neither stationary nor normally distributed. Akaike information criterion (AIC) and Bayesian information cri terion (BIC) were used to select the best fitting distribution at a particular site. The findings revealed that both maximum and minimum temperatures series at all the stations belong to the Weibull domain of attraction. The findings from the Mann-Kendall (M-K) test and time series plots trend analyses showed that there is a monotonic downward and upward long-term trend in minimum and maximum temperature data, respectively. Two fundamental approaches of EVT, block maxima and peaks-over-threshold (POT), were used in this dissertation. The generalised extreme value (GEV), generalised Pareto (GP) and Poisson point process distributions were fitted to the data set for each station. In order to a, DST National Research Foundation (NRF)

Approximately 25% of mammals are currently threatened with extinction, a risk that is amplified under climate change. Species persistence under climate change is determined by the combined effects of climatic factors on multiple demographic rates (survival, development and reproduction), and hence, population dynamics. Thus, to quantify which species and regions on Earth are most vulnerable to climate‐driven extinction, a global understanding of how different demographic rates respond to climate is urgently needed.Here, we perform a systematic review of literature on demographic responses to climate, focusing on terrestrial mammals, for which extensive demographic data are available.To assess the full spectrum of responses, we synthesize information from studies that quantitatively link climate to multiple demographic rates. We find only 106 such studies, corresponding to 87 mammal species. These 87 species constitute <1% of all terrestrial mammals.Our synthesis reveals a strong mismatch between the locations of demographic studies and the regions and taxa currently recognized as most vulnerable to climate change. Surprisingly, for most mammals and regions sensitive to climate change, holistic demographic responses to climate remain unknown. At the same time, we reveal that filling this knowledge gap is critical as the effects of climate change will operate via complex demographic mechanisms: a vast majority of mammal populations display projected increases in some demographic rates but declines in others, often depending on the specific environmental context, complicating simple projections of population fates.Assessments of population viability under climate change are in critical need to gather data that account for multiple demographic responses, and coordinated actions to assess demography holistically should be prioritized for mammals and other taxa.

Wintertime warm extremes in the high Arctic, primarily associated with intrusions of moist airmasses from the midlatitudes, have occurred with an ostensibly high frequency in recent years. Here, we compute the temperature anomaly return values associated with such events for long return times. Our approach, which we term space-time maxima-exposure (STM-E), improves on conventional extreme value estimates performed on a single-location basis by explicitly taking into account the spatial structure of the moisture intrusions driving the temperature extremes. We specifically show that the STM-E approach provides spatially smoother return value estimates, a lower uncertainty in the parameters of the extreme value distribution fits and mitigates the single-location underestimation of the magnitude of return values of temperature extremes.

To understand whether high temperatures and temperature extremes are important for climate change adaptation in Scotland, we place the 2018 heatwave in the context of past, present, and future climate, and provide a rapid but comprehensive impact analysis. The observed hottest day (d), 5 d, and 30 d period of 2018 and the 5 d period with the warmest nights had return periods of 5-15 years for 1950-2018. The warmest night and the maximum 30 d average nighttime temperature were more unusual with return periods of >30 years. Anthropogenic climate change since 1850 has made all these high-temperature extremes more likely. Higher risk ratios are found for experiments from the CMIP6-generation global climate model HadGEM3-GA6 compared to those from the very-large ensemble system weather@home. Between them, the best estimates of the risk ratios for daytime extremes range between 1.2-2.4, 1.2-2.3, and 1.4-4.0 for the 1, 5, and 30 d averages. For the corresponding nighttime extremes, the values are higher and the ranges wider (1.5- >50, 1.5-5.5, and 1.6- >50). The short-period nighttime extremes were more likely in 2018 than in 2017, suggesting a contribution from year-to-year climate variability to the risk enhancement of extreme temperatures due to anthropogenic effects. Climate projections suggest further substantial increases in the likelihood of 2018 temperatures between now and 2050, and that towards the end of the century every summer might be as hot as 2018. Major negative impacts occurred, especially on rural sectors, while transport and water infrastructure alleviated most impacts by implementing costly special measures. Overall, Scotland could cope with the impacts of the 2018 heatwave. However, given the likelihood increase of high-temperature extremes, uncertainty about consequences of even higher temperatures and/or repeated heatwaves, and substantial costs of preventing negative impacts, we conclude that despite its cool climate, high-temperature extr

In the first chapter of this dissertation, I find that an increase in the likelihood of extreme temperatures leads to a decline in the availability of credit in a region. I also document that for certain loan types, such as a revolving line of credit, the price of credit is increasing in the likelihood of extreme temperatures. Lastly, I find that temperature shocks may propagate from one region to other regions via a bank lending channel. Such indirect exposure, to temperature shocks elsewhere, adversely affects firm-level outcomes.The second chapter of this dissertation focuses on the implications of temperature extremes for small businesses in a region. I find that an increase in the likelihood of extreme temperature leads to an adverse impact on the availability of credit in a region. I find that the average adverse effect of extreme temperatures on credit availability is present for all bank types based on size. The adversity of extreme temperature effect, on credit availability in a region, increases with bank size. In the third chapter of this dissertation, I propose a new heterogeneous-agent stochastic discount factor (SDF) that equals the previous period investment weighted average of agents' SDFs. I implement this SDF on the consumption growth of cohorts of households in the Consumer Expenditure Survey dataset from the U.S. Bureau of Labor Statistics. I use factor analysis to reduce the impact of measurement error present in consumption data. For quarterly data observed at a monthly frequency, the investment weighted SDF reconciles the historical equity premium for relative risk aversion of 7. The proposed SDF fares well when tested using classical asset pricing tests like Hansen-Jagannathan volatility bounds and JT test. The weighting methodology is the primary driver of my results.

We present the second update to a data set of gridded land‐based temperature and precipitation extremes indices: HadEX3. This consists of 17 temperature and 12 precipitation indices derived from daily, in situ observations and recommended by the World Meteorological Organization (WMO) Expert Team on Climate Change Detection and Indices (ETCCDI). These indices have been calculated at around 7,000 locations for temperature and 17,000 for precipitation. The annual (and monthly) indices have been interpolated on a 1.875°×1.25° longitude‐latitude grid, covering 1901–2018. We show changes in these indices by examining ”global”‐average time series in comparison with previous observational data sets and also estimating the uncertainty resulting from the nonuniform distribution of meteorological stations. Both the short and long time scale behavior of HadEX3 agrees well with existing products. Changes in the temperature indices are widespread and consistent with global‐scale warming. The extremes related to daily minimum temperatures are changing faster than the maximum. Spatial changes in the linear trends of precipitation indices over 1950–2018 are less spatially coherent than those for temperature indices. Globally, there are more heavy precipitation events that are also more intense and contribute a greater fraction to the total. Some of the indices use a reference period for calculating exceedance thresholds. We present a comparison between using 1961–1990 and 1981–2010. The differences between the time series of the temperature indices observed over longer time scales are shown to be the result of the interaction of the reference period with a warming climate. The gridded netCDF files and, where possible, underlying station indices are available from www.metoffice.gov.uk/hadobs/hadex3 and www.climdex.org., Robert Dunn was supported by the Met Office Hadley Centre Climate Programme funded by BEIS and Defra (GA01101) and thanks Nick Rayner and Lizzie Good for helpful comments on the manuscript. Lisa Alexander is supported by the Australian Research Council (ARC) Grants DP160103439 and CE170100023. Markus Donat acknowledges funding by the Spanish Ministry for the Economy, Industry and Competitiveness Ramón y Cajal 2017 Grant Reference RYC‐2017‐22964. Mohd Noor'Arifin Bin Hj Yussof and Muhammad Khairul Izzat Bin Ibrahim thank the Brunei Darussalam Meteorological Department (BDMD). Ying Sun was supported by China funding agencies 2018YFA0605604 and 2018YFC1507702. Fatemeh Rahimzadeh and Mahbobeh Khoshkam thank I.R. of Iranian Meteorological Organization (IRIMO) and the Atmospheric Science and Meteorological Organization Research Center (ASMERC) for Data and also sharing their experiences, especially Abbas Rangbar. Jose Marengo was supported by the National Institute of Science and Technology for Climate Change Phase 2 under CNPq Grant 465501/2014‐1, FAPESP Grants 2014/50848‐9 and 2015/03804‐9, and the National Coordination for High Level Education and Training (CAPES) Grant 88887.136402‐00INCT. The team that worked on the data in West Africa received funding from the UK's National Environment Research Council (NERC)/Department for International Development DFID) Future Climate For Africa programme, under the AMMA‐2050 project (Grants NE/M020428/1 and NE/M019969/1). Data from Southeast Asia (excl. Indonesia) was supported by work on using ClimPACT2 during the Second Workshop on ASEAN Regional Climate Data, Analysis and Projections (ARCDAP‐2), 25–29 March 2019, Singapore, jointly funded by Meteorological Service Singapore and WMO through the Canada‐Climate Risk and Early Warning Systems (CREWS) initiative. This research was supported by Thai Meteorological Department (TMD) and Thailand Science Research and Innovation (TSRI) under Grant RDG6030003. Daily data for Mexico were, Peer Reviewed, Postprint (published version)

© 2020, The Author(s). Monitoring and management of several environmental and socioeconomic sectors require climate data that can be summarized using a set of standard and meaningful climate metrics. This study describes a newly developed gridded dataset for the whole of Europe, which employed a set of 125 climate indices spanning different periods based on data availability, but mainly 1950–2017 and 1979–2017. This dataset comprehensively summarizes climate variability in Europe for a wide range of climate variables and conditions, including air temperature, precipitation, biometeorology, aridity, continentality, drought, amongst others. Climate indices were computed at different temporal scales (i.e. monthly, seasonal and annual) and mapped at a grid interval of 0.25°. We intend to update these indices on an annual basis. This dataset is freely available to research and end-user communities.

The world is warming, with both extreme and mean temperatures getting warmer. But how extremes are changing and will change relative to the mean remains less clear. Disproportionate rates of change between extreme and mean temperatures need to be better understood because this changes the shape of the distribution, affecting the probability of extreme events and thus their impacts. Therefore, the goal of this thesis is to understand if, when and where disproportionate rates of change occur in the past and future and it does this by using observations, reanalyses and climate models. I find that for past decades, cold extremes have been warming faster than the mean for much of the Northern Hemisphere extratropics, while warm extremes have been warming faster than the mean in some subtropical regions. Future changes are systematic and robust across a range of climate model simulations. The most striking disproportionate changes are in the Northern Hemisphere mid- to high-latitudes, where cold extremes are projected to warm substantially faster than mean temperatures in all seasons except boreal summer. Exploring conditions on or leading into the day of the projected cold extremes reveals that the disproportionate warming is driven by different mechanisms in different seasons. In boreal winter, reduced cold air advection is the dominant driver, circulating anomalously warm temperatures from the Arctic to lower latitudes. But during spring and autumn, it is mostly due to feedbacks related to decreases in snow cover. Analyses of temperature extremes have inherent uncertainties. I evaluate several commonly used reanalyses with a gridded in situ-based daily temperature dataset to assess sensitivities related to dataset choice. Trends in extremes and statistical moments, other than the mean, exhibit sensitivity. However, the conclusions drawn in this thesis remain robust irrespective of dataset choice, and regardless of methodological choice including choice of base period a

Globally, anomalously warm temperature events have increased by 34% in frequency and 17% in duration from 1925 to 2016 with potentially major impacts on coastal ecosystems. These “marine heatwaves” (MHWs) have been linked to changes in primary productivity, community composition and biogeography of seaweeds, which often control ecosystem function and services. Here we journalarticle the literature on seaweed responses to MHWs, including 58 observations related to resistance, bleaching, changes in abundance, species invasions and local to regional extinctions. More records existed for canopy-forming kelps and bladed and filamentous turf-forming seaweeds than for canopy-forming fucoids, geniculate coralline turf and crustose coralline algae. Turf-forming seaweeds, especially invasive seaweeds, generally increased in abundance after a MHW, whereas native canopy-forming kelps and fucoids typically declined in abundance. We also found four examples of regional extinctions of kelp and fucoids following specific MHWs, events that likely have long term consequences for ecological structure and functioning. Although a relatively small number of studies have described impacts of MHWs on seaweed, the broad range of documented responses highlights the necessity of better baseline information regarding seaweed distributions and performance, and the need to study specific characteristics of MHWs that affect the vulnerability and resilience of seaweeds to these increasingly important climatic perturbations. A major challenge will be to disentangle impacts caused by the extreme temperature increases of MHWs itself from co-occurring potential stressors including altered current patterns, increasing herbivory, changes in water clarity and nutrient content, solar radiation and desiccation stress in the intertidal zone. With future increases anticipated in the intensity, duration and frequencies of MHWs, we expect to see more replacements of large long-lived habitat forming seaweeds wi

The equatorial island of Borneo is a deforestation hotspot. However, the influence of forest loss on the island's climate remains largely unexplored. Here, we examine how forest loss is related to changes in ground-based records of temperature (1961-2007) and precipitation (1951-2007), and MODIS data for temperature (2002-2016). Analyses were performed for the entire island, lowland areas (<200 m ASL), and nine selected watersheds. We found a strong island-wide relationship between forest loss and increases in daily temperature and reductions in daily precipitation. The relationship between deforestation and changes in local climate was most pronounced for watersheds in southeast Borneo, which have lost 40-75 of their forests since 1973. These watersheds also had a significantly higher frequency of temperatures above 31°C. Watersheds in north and northwest Borneo, which have lost 5-25 of their forest cover, maintained a more stable climate with a similar distribution of mean and extreme warm temperatures between forest and modified forest areas. Watersheds with >15 forest loss had a >15 reduction in rainfall. We conclude that loss of forest in Borneo has increased local daily temperatures and temperature extremes, and reduced daily precipitation. © 2018 The Author(s). Published by IOP Publishing Ltd.

Extreme weather occurrences carry enormous social and economic costs and routinely garner widespread scientific and media coverage. The ability to predict these events is therefore a topic of crucial importance. Here we propose a novel predictability pathway for extreme events, by building upon recent advances in dynamical systems theory. We show that simple dynamical systems metrics can be used to identify sets of large-scale atmospheric flow patterns with similar spatial structure and temporal evolution on time scales of several days to a week. In regions where these patterns favor extreme weather, they afford a particularly good predictability of the extremes. We specifically test this technique on the atmospheric circulation in the North Atlantic region, where it provides predictability of large-scale wintertime surface temperature extremes in Europe up to 1week in advance. Plain Language Summary Extreme weather occurrences carry enormous social and economic costs and routinely garner widespread scientific and media coverage. The ability to predict these events is therefore a topic of crucial importance. Here we propose a novel analysis technique for improving the prediction of extreme events, which identifies the large-scale atmospheric circulation configurations affording the best predictability. We specifically test our technique on the atmospheric circulation in the North Atlantic region, where it provides predictability of large-scale wintertime surface temperature extremes in Europe up to 1week in advance.

The analysis of spatiotemporal changes of temperature extremes in Serbia, based on 18 ETCCDI indices, was performed using daily minimum and maximum temperature observations from 26 meteorological stations over the period 1961-2010. The observation period was divided into two sub-periods (1961-1980 and 1981-2010) according to the results of the sequential Mann-Kendall test. Temporal trends were evaluated by a least-squares linear regression method. The average annual minimum temperature displayed a mixed pattern of increasing, decreasing, and no trends over 1961-1980 and a significant increasing trend over 1981-2010 across the whole country, with a regionally averaged rate of 0.48 degrees C per decade. The average annual maximum temperature showed a decreasing trend during 1961-1980 and a significant increasing trend at all stations during 1981-2010, with a regionally averaged rate of 0.56 degrees C per decade. Hot indices exhibited a general cooling tendency until 1980 and a warming tendency afterwards, with the most pronounced trends in the number of summer and tropical days during the first period and in the frequency of warm days and nights in the second. Cold indices displayed a mostly warming tendency over the entire period, with the most remarkable increase in the lowest annual maximum temperature and the number of ice days during the first period and in the frequency of cool nights during the second. At most stations, the diurnal temperature range showed a decrease until 1980 and no change or a slight increase afterwards. The lengthening of the growing season was much more pronounced in the later period. The computed correlation coefficient between the annual temperature indices and large-scale circulation features revealed that the East Atlantic pattern displayed much stronger association with examined indices than the North Atlantic Oscillation and East Atlantic/West Russia pattern.

The health gap between Indigenous and non-Indigenous Australians may be exacerbated by climate change if temperature extremes have disproportionate adverse effects on Indigenous people. To explore this issue, we analysed the effect of temperature extremes on hospital admissions for respiratory diseases, stratified by age, Indigenous status and sex, for people living in two different climates zones in the Northern Territory during the period 1993–2011. We examined admissions for both acute and chronic respiratory diagnoses, controlling for day of the week and seasonality variables. Our analysis showed that: (1) overall, Indigenous hospital admission rates far exceeded non-Indigenous admission rates for acute and chronic diagnoses, and Top End climate zone admission rates exceeded Central Australia climate zone admission rates; (2) extreme cold and hot temperatures were associated with inconsistent changes in admission rates for acute respiratory disease in Indigenous and non-Indigenous children and older adults; and (3) no response to cold or hot temperature extremes was found for chronic respiratory diagnoses. These findings support our two hypotheses, that extreme hot and cold temperatures have a different effect on hospitalisations for respiratory disease between Indigenous and non-Indigenous people, and that these health risks vary between the different climate zones. We did not, however, find that there were differing responses to temperature extremes in the two populations, suggesting that any increased vulnerability to climate change in the Indigenous population of the Northern Territory arises from an increased underlying risk to respiratory disease and an already greater existing health burden.

Understanding how climate extremes have changed in the recent past and how they will change in the future is crucial for preparing for future climate change. Natural variability and anthropogenic climate change are both known to significantly influence the frequency and severity of temperature and precipitation extremes, so it is vital to better understand these effects. A case study of frost days in southern Australia first illustrates how short-term variations in climate can sometimes override any global warming signal for a period of time. Some unexpected frost day ‘increases’ are found over 1981-2011, despite a longer-term warming signal. A link to the concurrent precipitation decline and associated reduced cloudiness is identified for south-eastern Australia. The remainder of this thesis investigates variations and trends in the fraction of area experiencing daily temperature and precipitation extremes in four continental regions: Europe, North America, Asia and Australia, and the Northern Hemisphere. A new method based on existing extreme indices is used to investigate changes in five temperature and precipitation components, including maximum and minimum temperature components, and total precipitation, heavy daily precipitation and wet/dry day components. Near-global increases in area experiencing much-above-average warm days and nights and decreases in the area experiencing much-above-average cool days and nights are found. Over the Northern Hemisphere regions, increases in the area affected by wet extremes are also identified. For Australia, the spatial extent of precipitation extremes is primarily influenced by natural variability. Using simulations from eight global climate models under different radiative forcing scenarios, an anthropogenic contribution to the increases in area affected by warm temperature extremes is identified for all regions. Over Europe, an anthropogenic contribution to the increases in area affected by a much-above-average contribut

A multi-model ensemble of regional climate projections is used to estimate the climate change signal in terms of temperature and precipitation for the city of Aachen, Germany, until the end of the current century. Since the combination of heat and high moisture content in the ambient air is assumed to adversely affect human health, the equivalent temperature is employed as an indicator for heat stress and applied to identify heat waves. As prolonged periods of high temperatures may also cause summer drought, summer precipitation and dry periods are analyzed as well. The study refers to regional climate projections (A1B emission scenario) of the statistical climate models STARII and WETTREG and the dynamical climate models REMO and COSMO-CLM. The model outputs are compared a) with each other in order to assess discrepancies between them and b) with the 30-year baseline period of 1971–2000 in order to estimate future changes in heat load and precipitation patterns for the summer months of June, July and August. Based on median realizations of the model runs, further warming of approximately 1–2 K is expected by the middle of the 21st century and 3–4 K by 2100. These changes will probably be accompanied by an increase in variance. Maximum temperature shows the greatest enhancement ( +1.9 K 2031–2060 and 4.3 K 2071–2100, ensemble mean) causing almost a doubling of (extreme) hot days and a trebling of tropical nights as soon as the middle of the century. According to this temperature development heat waves are likely to last longer and occur more often in future whereas their intensity is not expected to change significantly. An increasing number of heat waves is concurrent with a decreasing amount of rainfall in the summer months until 2100. All four climate projections indicate a decrease in precipitation in summer until 2100 with -17 % on average. The highest decrease is shown by COSMO-CLM with -30 % rainfall in June for the period of 2071–2100. Dry periods are expect, Peer Reviewed

While numerous studies have addressed changes in climate extremes, analyses of concurrence of climate extremes are scarce, and climate change effects on joint extremes are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature extremes in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. The joint occurrences of precipitation and temperature extremes simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for warm/wet, warm/dry, cold/wet, and cold/dry combinations of joint extremes. The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint warm/dry and warm/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent extremes, the CMIP5 climate model simulations are in reasonable overall agreement with observations. However, the results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.

We analyze temporal and spatial patterns of temperature change over Spain during the period 1850–2005, using daily maximum (T max), minimum (T min), and mean (T mean) temperatures from the 22 longest and most reliable Spanish records. Over mainland Spain, a significant (at 0.01 level) warming of 0.10°C/decade is found for the annual average of T mean. Autumn and winter contributed slightly more than spring and summer to the annual warming over the 1850–2005 period. The overall warming is also associated with higher rates of change for T max than T min (0.11° versus 0.08°C/decade for 1850–2005). This asymmetric diurnal warming increased in the twentieth century (0.17° versus 0.09°C/decade during 1901–2005). Nevertheless, at many (few) individual stations, the difference between T max and T min is not statistically significant over 1850–2005 (1901–2005). Principal Component Analysis has been carried out to identify spatial modes of Spanish long-term temperature variability (1901–2005). Three principal spatial patterns are found, Northern Spain, Southeastern and Eastern Spain, and Southwestern Spain. All three patterns show similar significant warming trends. The overall warming has been more associated with reductions in cold extremes, as opposed to increases in warm extremes. Estimated trends in the number of moderately extreme cold days (T max < 10th percentile) and moderately extreme cold nights (T min < 10th percentile) show significant reductions of 0.74 and 0.54 days/decade, respectively, over 1850–2005. Moderately extreme warm days and nights (T max and T min > 90th percentile) increased significantly but at lower rates of 0.53 and 0.49 days/decade.

Rubber pad expanded neoprene is currently positioned in the container body assembly. It is fastened with adhesive to the metal end, which is crimped to the outer body portion of the fiber container. Extensive testing was performed on the cartridge support during design, pre-production, and FAT testing on past and current contracts by U.S. Army Armament Research, Development and Engineering Center personnel. The cartridge support has shown excellent strength at both elevated and negative temperatures. The container itself is designed and manufactured in a way as to add additional strength to the support. The fiber container, by forming an exterior barrier around the cartridge support also helps in controlling the amount of expansion the cartridge support can achieve. By removing the rubber pad, an initial cost savings of $0.32 per container would be achieved., The original document contains color images.

As Operation Enduring Freedom moves into its second year, the engineers in Afghanistan have moved beyond initial-entry operations. They have started to attack some of the daunting general engineering and mobility challenges posed by this arid and austere environment. The 82d Airborne Division's 307th Engineer Battalion airfield repair team at Kandahar International Airport has introduced several construction initiatives in runway repair that will not only prolong the life span of the deteriorating airfield, but also may change the way contingency airfields are repaired in the future., Published in Engineer: The Professional Bulletin of Army Engineers, v33, p20-22, Oct-Dec 2003. PB-5-03-4.

In earlier papers (Model Atmospheres I and II), a procedure was developed for determining the most probable vertical temperature profile associated with the occurrence of 1% world-wide temperature extremes at mandatory-pressure levels, and at stations where such extremes are known to exist. The same technique based upon the use of the stepwise multiple regression analysis was employed in this study to determine vertically consistent atmospheres corresponding to known oceanic extremes. Cold open-ocean extremes were found to exist up to 300 mb primarily near the Labrador coast at OSV 'B', while the warm-open ocean extremes were found to exist in the vicinity of Majuro atoll of the Marshall Islands. The warmest of all sea-extremes for near-port conditions was found to exist in the Persian Gulf (near Station Bahrain). (Modified author abstract)

Straub, S. C., Wernberg, T., Thomsen, M. S., Moore, P. J., Burrows, M., Harvey, B. P., & Smale, D. A. (2019). Resistance to obliteration; responses of seaweeds to marine heatwaves. Frontiers in Marine Science, 6, Article 763. https://doi.org/10.3389/fmars.2019.00763