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Summary: Success of establishing native trees in cool temperate environments depends on the ability of seedlings to withstand subzero temperatures and recurrent frosts. This study compared the survival and growth of five tree and shrub species with two guard types at three landscape positions in an upland pasture. Seedlings were planted between December 2013 and March 2014. Half of the seedlings were planted in tall Corflute® guards (60 cm high), and the remaining seedlings were interplanted in milk cartons (30 cm). Seedling survival and height were measured in November 2014. Hourly temperature readings were recorded between March and November 2014. Seedling height for all species was greater in tall guards than milk cartons at all landscape positions, possibly at least partly due to etiolation. However, seedlings in tall guards survived better than seedlings in milk cartons at mid‐ and upper‐slope positions. Higher temperatures may have benefited seedling performance by prolonging the growing season as average maximum temperature was significantly higher inside tall guards than milk cartons and ambient conditions at all landscape positions. Average daily temperature was significantly higher in tall guards compared to milk cartons and ambient conditions at the upper‐slope site only. There were no significant differences in average minimum temperature between guard types at all landscape positions. [ABSTRACT FROM AUTHOR]

Purpose To examine the relationship between human corneal and environmental temperature. Methods An infrared camera was used to measure the corneal surface temperature in a group of healthy volunteers as well as in an experimental setting with donor corneas and an artificial anterior chamber, employing circulating saline at +37°C. Liquid nitrogen was used to obtain a very low temperature in the experimental setting. High ambient temperature measurements were performed in a sauna. Results In healthy volunteers, the cornea required at least 20-30 min to adapt to change in ambient temperature. The relationship between corneal and external temperature was relatively linear. At the two extremes, +83°C and −40°C, the corneal temperature was +42°C and +25.1°C, respectively. In the experimental setting, corneal temperature was +24.3°C at air temperature −40°C. Conclusion A rather stable aqueous humour temperature of +37°C and high thermal conductivity of the corneal tissue prevent corneal frostbite even at extremely low ambient temperatures. [ABSTRACT FROM AUTHOR]

Stratospheric Sounding Units (SSU) on the NOAA polar-orbiting satellites measured infrared radiances in the 15 μm CO2 band between late 1978 and mid-2006. From these radiances a time series of layer-mean stratospheric temperatures has been derived by several groups. Discrepancies in these temperature analyses have been highlighted recently and efforts are now underway to resolve the differences between them. This article is the Met Office response summarising the issues to be resolved in creating a climate data record from the different SSUs, including corrections for radiometric, spectroscopic and tidal differences. Calibration issues identified include the SSU space-view anomaly and radiometric anomalies in the NOAA-9 observations. The spectroscopic correction required for changing pressures in the pressure modulator cells is also outlined. Themost important correction for the time series is for the solar diurnal and semi-diurnal tides as the satellite overpass local times change. Comparisons with other stratospheric temperature trend analyses are made and the reasons for the differences discussed. The time series presented here show sustained drops in stratospheric temperatures at all levels after the El Chichon and Pinatubo eruptions but only small trends to lower temperatures between eruptions. [ABSTRACT FROM AUTHOR]

ABSTRACT We assess the uncertainties in the monthly 5-km resolution gridded values and derived areal averages of UK temperature and precipitation since 1910, and sunshine since 1929, developed by the Met Office National Climate Information Centre. Subsampling experiments are used to estimate the sampling uncertainties as a function of the density of the observing network; these estimates are then ascribed to historical gridded values and area averages according to the historical sampling density. Available historical manuscripts could support future extension of gridded and areal-average records back to 1901 for temperature, about 1871 for precipitation and 1921 for sunshine, with sufficient sampling to provide reliable historical context for current events. We combine the sampling uncertainties since 1910 with estimated calibration and measurement uncertainties to yield total uncertainties that we tabulate and illustrate in association with selected series. Methods and results are discussed in the light of existing estimates of uncertainties in Central England temperature and UK regional precipitation. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, we develop long-term series of monthly average temperatures and precipitation totals for the modern recording site on the Falkland Islands (at Mount Pleasant Airport). The air temperature series extends back to 1895, but with 16 missing months in 1902 and 1907/8. The precipitation series extends back to 1904, but has all but four months missing in the period 1921-1923. All missing values during the early 1980s are infilled using the ERA-Interim Reanalysis. We compare long-term variations in both variables with the nearest long-term record from Punta Arenas in Chile, and for air temperature with a sea surface temperature series from around the islands. [ABSTRACT FROM AUTHOR]

Stratospheric temperature series derived from the Advanced Microwave Sounding Unit (AMSU) on board successive NOAA satellites reveal, during periods of overlap, some bias and drifts. Part of the reason for these discrepancies could be atmospheric tides as the orbits of these satellites drifted, inducing large changes in the actual times of measurement. NOAA 15 and 16, which exhibit a long period of overlap, allow deriving diurnal tides that can correct such temperature drifts. The characteristics of the derived diurnal tides during summer periods is in good agreement with those calculated with the Global Scale Wave Model, indicating that most of the observed drifts are likely due to the atmospheric tides. Cooling can be biased by a factor of 2, if times of measurement are not considered. When diurnal tides are considered, trends derived from temperature lidar series are in good agreement with AMSU series. Future adjustments of temperature time series based on successive AMSU instruments will require considering corrections associated with the local times of measurement. [ABSTRACT FROM AUTHOR]

Values of 10 m wind speed have been plotted against screen temperature during morning warming and averaged over several years for a number of sites within Great Britain. When the temperature is referenced to that at the time of the coming evening transition the plots give consistent lines with a gradient dependent on geostrophic wind. However the gradient for a given geostrophic wind varies between sites. Comparison with similar plots made during evening cooling shows that the wind plot against temperature increases relatively abruptly at some stage during the early hours of the morning and then increases to its midday maximum with a reduced wind-temperature gradient to that in the evening. However, as with the evening plots, the gradients of the morning plots increase in hillier terrain. The effect of wind direction on the gradients during morning and evening is also described in order to verify that the effect of topography on the plots is consistent. A one-dimensional numerical model is used to simulate both transitions. It is shown that external drag factors such as form drag in the region of low hills are not sufficient to explain the observations. Only an external drag of the type given by a simple formulation of gravity wave generation and absorption within the stable boundary layer gives good agreement with the observations. This suggests that an important factor causing the wind to drop during the evening cooling is gravity wave drag and its relative absence, due to the near-surface convective layer, is a factor during the morning wind increase. [ABSTRACT FROM AUTHOR]

ABSTRACT The global increase of temperature, together with more frequent severe winters and summer heat waves may lead to a change in energy consumption and agricultural production. Cooling, heating, and growing degree-days ( CDD, HDD, and GDD), respectively, are used to quantify the energy needed to condition or heat buildings, and to study the growing season. Using a new dataset made of 4023 daily TN- TM- TX series for the period 2001-2011 and 3897 monthly TM homogenized series for the period 1951-2011, we computed CDD, HDD, GDD, and Winkler Index ( WI) for Europe. We developed a model that correlates degree-days calculated with daily TN- TM- TX data with degree-days obtained by monthly TM data, in the overlapping period 2001-2011. A set of parameters for each station was then applied to the corresponding 1951-2011 monthly records. We interpolated the parameters and the reconstructed degree-day series onto a European 0.25° × 0.25° grid: with these gridded parameters, one can estimate the degree-days for any European location if only monthly TM is available. We present maps of HDD, CDD, GDD, and WI for the period 1951-2010. To validate them, we run a comparison in the Carpathian area using an independent dataset (from the CARPATCLIM project). The regional records show high correlations, especially for HDD ( r > 0.99) and WI ( r > 0.98). Subsequently, we performed a linear trend analysis on European and regional basis. HDD showed a significant decrease almost everywhere in Europe, whereas CDD, GDD, and WI showed a significant increase in particular in the last 30 years in the Mediterranean region. Moreover, WI indicated that new areas in France and central Europe became suitable for grape cultivation in the last decades. [ABSTRACT FROM AUTHOR]

Gridded temperature datasets covering the UK at 5 km × 5 km resolution have been analysed for temporal and spatial patterns of change and variability. Decadal-scale variability is visualized by smoothing the data series using a kernel smoother. Trends have been analysed by comparing averages for a baseline period with averages for a recent period, as well as using linear regression. Spatial patterns of change have been mapped by calculating trends for each grid point. Monthly gridded datasets of daily maximum, minimum and mean air temperatures are available from 1910 to date. These show statistically significant increases for all parts of the UK, with the rate of change increasing from the north and west to the south and east. Seasonally, the least significant changes have occurred in the winter, with significant increases for most districts for all of the other seasons. Derived indices based on daily temperature are available from 1961 onwards. There have been significant decreases in heating degree days and increases in growing degree days for all districts, while changes in cooling degree days are less significant as the values are low and inter-annual variability dominates. There have been significant decreases in frost days, especially in spring and autumn, and this is linked to significant increases in growing season length, especially for Scotland. [ABSTRACT FROM AUTHOR]

Aim Southern temperate tree lines are found at low elevations compared with their Northern Hemisphere counterparts. They are also regarded as forming at warm temperatures, which has been attributed to taxon-specific limitations. Using New Zealand tree lines as an example, we assess whether these tree lines are anomalously warm compared with the global mean. Location New Zealand. Methods Soil and air temperatures were measured over 2 years at six New Zealand tree line sites, and compared with other local and global growing season temperature data. In New Zealand and other oceanic regions, the long, variable seasonal transitions make calculations of mean growing season temperatures highly sensitive to how the growing season is defined. We used both the conventional (wide) definition (from when mean weekly root-zone temperature exceeds 3.2 °C in spring, to when it first falls below 3.2 °C in autumn) and a narrow definition (the period during which temperatures are continuously above 3.2 °C). Application of these criteria leads to similar mean growing season temperatures in continental regions, but different ones in oceanic regions. We tested whether growing season temperatures differ between northern and southern temperate tree lines. Results New Zealand tree lines had a mean root-zone temperature during the wide growing season of 7.0 °C ± 0.4 SD, not significantly different from those at northern temperate tree lines. The mean temperature of the narrow growing season was 7.8 °C, warmer than tree lines elsewhere, but still within the range reported for temperate tree lines (7-8 °C). Main conclusions Whilst they are found at lower elevations, New Zealand tree lines form at temperatures similar to those at Northern Hemisphere temperate tree lines. Together with similar recent evidence from Chile, these results refute the previously postulated taxon-specific limitation hypothesis, and suggest these southern temperate tree lines are not climatically depressed, but are governed by the same thermal threshold as other tree lines worldwide. [ABSTRACT FROM AUTHOR]

Changing temperature can substantially shift ecological communities by altering the strength and stability of trophic interactions. Because many ecological rates are constrained by temperature, new approaches are required to understand how simultaneous changes in multiple rates alter the relative performance of species and their trophic interactions. We develop an energetic approach to identify the relationship between biomass fluxes and standing biomass across trophic levels. Our approach links ecological rates and trophic dynamics to measure temperature-dependent changes to the strength of trophic interactions and determine how these changes alter food web stability. It accomplishes this by using biomass as a common energetic currency and isolating three temperature-dependent processes that are common to all consumer-resource interactions: biomass accumulation of the resource, resource consumption and consumer mortality. Using this framework, we clarify when and how temperature alters consumer to resource biomass ratios, equilibrium resilience, consumer variability, extinction risk and transient vs. equilibrium dynamics. Finally, we characterise key asymmetries in species responses to temperature that produce these distinct dynamic behaviours and identify when they are likely to emerge. Overall, our framework provides a mechanistic and more unified understanding of the temperature dependence of trophic dynamics in terms of ecological rates, biomass ratios and stability. [ABSTRACT FROM AUTHOR]

The complexity of soil evaporation, depending on the atmospheric conditions, emphasizes the importance of its quantification under potential changes in ambient air temperature, Ta, and relative humidity, RH. Mass loss, soil matric tension, and meteorological measurements, carried out in a climate-controlled laboratory, were used to study the effect of ambient conditions on the drying rates of a porous medium. A set of evaporation experiments from initially saturated sand columns were carried out under constant Ta of 6, 15, 25, and 35°C and related RH (0.66, 0.83, 1.08, and 1.41 kPa, respectively). The results show that the expected increase of the stage 1 ( S1) evaporation rate with Ta but also revealed an exponential-like reduction in the duration of S1, which decreased from 29 to 2.3 days (at Ta of 6 and 35°C, respectively). The evaporation rate, e( t), was equal to the potential evaporation, ep( t), under Ta = 6°C, while it was always smaller than ep( t) under higher Ta. The cumulative evaporation during S1 was higher under Ta = 6°C than under the higher temperatures. Evaporation rates during S2 were practically unaffected by ambient conditions. The results were analyzed using a mass transfer formulation linking e( t) with the vapor pressure deficit through a resistance coefficient r. It was shown that rS1 (the resistance during S1) is constant, indicating that the application of such an approach is straightforward during S1. However, for evaporation from a free water surface and S2, the resistances, rBL and rS2, were temperature-dependent, introducing some complexity for these cases. [ABSTRACT FROM AUTHOR]

ABSTRACT In-situ observations of surface air temperature at 55 weather stations in Iran are analysed for homogeneity and trends over the period 1960-2010. Among them 32 stations have data available for the whole period. The other 23 stations with shorter records are used only to confirm variability during overlapping periods. Discontinuities in the temperature series relate mostly to relocation and changes of environmental conditions at individual stations. These changes alter the statistical characteristics of temperature, including the mean, variance, and frequency distribution and introduce uncertainties in spatially averaged trends. This article determines new estimates of temperature trends over Iran after the detection of artificial change points and application of homogenization. The regional trend of temperature is estimated using seasonal and annual minimum and maximum temperature from stations that have identical variability across the country. The country may be segmented to 10 such regions in terms of trends and variability of temperature. There is little doubt that temperatures have increased in all regions at nearly equal rates of 0.4-0.5 and 0.2-0.3 (°C/decade) for minimum and maximum temperature, respectively in Iran. The finding in earlier work of a few individual stations with negative trends is found to be due to artificial effects such as relocation. [ABSTRACT FROM AUTHOR]

ABSTRACT Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest places in the world to one of the coolest summits in Africa. Associated with this environmental diversity and climate change, climatic extremes are expected to change over time and also vary across eco-environments in the country. This study was conducted to examine the trends of past precipitation and temperature extremes over three eco-environments in Ethiopia. The study involved analysis of 20 extreme indices computed from daily temperature and precipitation data spanning over 42 years (1967-2008). The climate data were obtained from 11 stations selected from three major eco-environments (pastoral, agropastoral and highland). The results indicated positive trends for maximum value of the maximum temperature ( TXx), warm days ( TX90p), warm nights ( TN90p) and warm spell duration indicators ( WSDI) and negative trends for cool days ( TX10p), cool nights ( TN10p) and cold spell duration indicators ( CSDI) in more than 8 of the 11 stations studied. However, most of the trends were not significant at many of the stations and the significant trends were not uniquely differentiated by eco-environments. Unlike temperature extremes, precipitation extreme trends showed high variability among nearby stations within eco-environments and were not significant at many of the stations studied. It is concluded that trends of temperature and precipitation extremes vary considerably among stations located within a given eco-environment indicating that the response of local climate to global warming could be different in physiographically diverse regions. [ABSTRACT FROM AUTHOR]

The maintenance of body temperature in endothermic animals imposes considerable metabolic costs that vary with air temperature fluctuations. To minimise these costs, endotherms can adopt certain behaviours to adjust the pattern of heat transfer between their bodies and the environment. In this study, we evaluated whether a small Neotropical primate, the black-fronted titi monkey ( Callicebus nigrifrons), living in a seasonal environment can use behavioural mechanisms to cope with fluctuations in the air temperature. We monitored the air temperature and the titi monkeys' behaviour over 1 yr. When the animals were inactive, we recorded the microhabitat used, the huddling between individuals and the body postures adopted. The monkeys primarily responded to air temperature fluctuations through microhabitat selection: they spent more time in sunny places and used higher strata of forest under lower temperatures. Moreover, they used sunny microhabitats during the first hour of their active period after colder nights. The monkeys did not huddle or change body postures in response to air temperature fluctuations. Huddling behaviour seemed to be primarily influenced by social interactions, and body postures were more energy conserving, regardless of temperature. Titi monkeys, however, used more energy-conserving postures and huddling behaviour under cloudy conditions than sunny conditions, suggesting that these behaviours may be important when they are unable to thermoregulate by microhabitat selection. We concluded that fluctuations in air temperature can promote significant changes in the behaviour of titi monkeys and can impose important restrictions on mammals' activities, even in tropical regions. [ABSTRACT FROM AUTHOR]

ABSTRACT The NASA announcement of record surface melting of the Greenland ice sheet in July 2012 led us to examine the atmospheric and oceanic climatic anomalies that are likely to have contributed to these exceptional conditions and also to ask the question of how unusual these anomalies were compared to available records. Our analysis allows us to assess the relative contributions of these two key influences to both the extreme melt event and ongoing climate change. In 2012, as in recent warm summers since 2007, a blocking high pressure feature, associated with negative NAO conditions, was present in the mid-troposphere over Greenland for much of the summer. This circulation pattern advected relatively warm southerly winds over the western flank of the ice sheet, forming a 'heat dome' over Greenland that led to the widespread surface melting. Both sea-surface temperature and sea-ice cover anomalies seem to have played a minimal role in this record melt, relative to atmospheric circulation. Two representative coastal climatological station averages and several individual stations in south, west and north-west Greenland set new surface air temperature records for May, June, July and the whole (JJA) summer. The unusually warm summer 2012 conditions extended to the top of the ice sheet at Summit, where our reanalysed (1994-2012) DMI Summit weather station summer (JJA) temperature series set new record high mean and extreme temperatures in 2012; 3-hourly instantaneous 2-m temperatures reached an exceptional value of 2.2°C at Summit on 11 July 2012. These conditions translated into the record observed ice-sheet wide melt during summer 2012. However, 2012 seems not to be climatically representative of future 'average' summers projected this century. [ABSTRACT FROM AUTHOR]

Water hyacinth, i.e., Eichhornia crassipes Solms can remove a large variety of different pollutants from water and are considered an excellent candidate for phytoremediation of contaminated waters. Nevertheless, exploitation of water hyacinth for phytoremediation has so far been limited to tropical or subtropical regions. In this study, the influence of temperature on the morphology, growth, and nutrient removal of water hyacinths was studied in a relatively low temperature range, 12-25°C, in the form of three night/day temperature cycles, i.e., 12/15°C, 15/20°C, and 15/25°C. It was shown that water hyacinth is very sensitive to temperature in the tested range and 15/25°C is the most favorable condition among the tested. A biomass productivity of 10.7 tons DW/ha/yr, total nitrogen removal rate of 400 kg N/ha/yr and total phosphorous removal rate of 65 kg P/ha/yr were estimated according to the experimental results on the basis of five operational months per year. No visible morphological changes were observed when the plants were cultivated at 15/20°C or 15/25°C but significant morphological changes were observed when the plants were transferred from a rooftop greenhouse to a growth chamber controlled at 12/15°C with plant size shrinking significantly. Nevertheless, substantial plant growth and nutrient removal were observed at 12/15°C, although with a prolonged adaptation phase of 2 weeks. Results of this research suggest good potential of water hyacinths for water phytoremediation in relatively cold regions such as Canada. © 2013 American Institute of Chemical Engineers Environ Prog, 32: 976-981, 2013 [ABSTRACT FROM AUTHOR]

ABSTRACT We examined trends in minimum and maximum temperatures in the Oahu during the period of past 39 (1969-2007) and 25 (1983-2007) years. We found a strong spatial and temporal variability in the temperature trends on Oahu. During the past 39 years, island-wide minimum temperature has increased by 0.17 °C/decade and shows a considerable variability in trends at individual location. There was no detectable trend found in maximum temperature over the same time period. The year 1983 was identified as the change point in the island-wide minimum temperature. During the recent 25 years annual and summer maximum temperature showed a decline while minimum temperature continued to increase. Trend in diurnal temperature range ( DTR) shows a decline during the past 39 years with a stronger decreasing trend during the recent 25 years. The trend in DTR for Oahu is much higher compared to the global DTR trend indicating a rapid warming in minimum temperature. Extreme temperature indices show a general warming during the past 39 years. There has been significant increase in tropical and warm nights at the two urban stations. Maximum temperature generally followed the Pacific Decadal Oscillation ( PDO) except the period when there is an increase in Hawaii Rainfall Index ( HRI). In contrast, minimum temperature showed better agreement with HRI compared to the PDO, at least up until 1999 after which it showed an increase. Despite the relative cooling in PDO during the recent decade an increase in minimum temperature can be attributed to a decline in HRI. [ABSTRACT FROM AUTHOR]

Rain-on-snow (ROS) runoff events are important hydro-meteorological phenomenon due to their association with flooding. The severity of ROS runoff events depends on the magnitude of the precipitation, air temperature elevation, snow water equivalent (SWE), and areal extent of the antecedent snowpack. Examining the consequences of these factors acting together creates challenges for both flood prediction and flood risk assessments. This study provides information on the spatial patterns, and seasonality of ROS events in New York. We examine the spatial and temporal variability of ROS events for water years 2004 to 2012 from SNOw Data Assimilation System products for New York. Liquid and solid precipitation, snow depth, snowmelt, SWE, maximum and minimum temperature, hydrograph characteristics, and annual peak flow are examined. There is significant positive correlation of ROS days and ROS triggered events with elevation and negative correlation of these events with increasing air temperature. Our study shows that ROS events are dominant in high elevation areas of Adirondack and Catskill regions, and their distribution varies with month. Cumulative runoffs from ROS events are generally greater than the rain-only runoff events. The majorities of annual peak flows in the study watersheds are the results of ROS events and lasted from a few days to many weeks. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT The thermal history and permafrost evolution in the Urengoy area of the West Siberian basin and in the Kuyumbinskaya area of the Siberian platform during the Pliocene-Quaternary were reconstructed numerically in a forward model from 3.4 Ma using the software package FROST, part of the basin modelling system GALO. Calculations suggest that variations in rock composition with depth strongly influenced permafrost evolution. Rock temperatures decreased by 15-20°C within the upper 1500 m of the sedimentary sequence because of climate cooling in the Pliocene-Holocene. The effect of cooling is greater in the Kuyumbinskaya area, which has a thinner sedimentary cover, than in the more northern Urengoy area. The model estimates permafrost depth and the stability zone of methane gas hydrate. An increase in salt content in porewater from 1 to 30 g/l lowers the melting temperature of ice by 2°С and decreases permafrost thickness by almost 100 m. The change in shape of the unfrozen water curve W(T), dependent upon the lithological composition of sedimentary rocks, strongly influences the numerical estimations of permafrost depth. The modelling demonstrates that permafrost thickness and temperature and heat flow distributions with depth in the basins calculated with climate variations of the last 50 ka differ significantly from the more accurate values obtained with climate variations during the last 200 ka, 1 Ma or 3.4 Ma. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT The disruptive potential of floods, drought, ice, and high water temperature on fishes in streams have been well documented. We examined the relationship between unexpected high flow events, low flow events coupled with low and high air temperature events, and a variety of ecological measures frequently used to quantify fish communities in streams, e.g. density. We developed a severity index to quantify concurrent extreme disturbances occurring over annual and summer periods. We anticipated that years or summers of high severity would result in changes in the fish community measures, e.g. low abundance. Despite the occurrence of severe events, there were relatively few instances of environmental severity resulting in consistent negative/positive changes in fish communities. Of the fish community measures, young-of-the-year (YOY) growth was most responsive to extremes. Low flow in combination with high temperature events significantly lowered YOY growth; whereas, unexpected high flows increased growth. Unexpected high flow events were associated with a significant negative effect on fish abundance and positive effects on biomass, YOY growth, and diversity during the summer period. The predictive power of abiotic-biotic regressions from the summer time period was generally greater than that from the annual time period. We suggest that high amounts of groundwater flow into the streams may buffer the impact of extreme environmental conditions. Our methodology of measuring extremes in flow and air temperature could be implemented over much larger scales for use in long-term monitoring impacts related to climate and land use change. Copyright © Her Majesty the Queen in Right of Canada 2012 [ABSTRACT FROM AUTHOR]

Because of its low topographic relief, unique hydrology, and the large interannual variability of precipitation, Florida is especially vulnerable to climate change. In this paper, we investigate a comprehensive collection of climate metrics to study historical trends in both averages and extremes of precipitation and temperature in the state. The data investigated consist of long-term records (1892-2008) of precipitation and raw (unadjusted) temperature at 32 stations distributed throughout the state. To evaluate trends in climate metrics, we use an iterative pre-whitening method, which aims to separate positive autocorrelation from trend present in time series. Results show a general decrease in wet season precipitation, most evident for the month of May and possibly tied to a delayed onset of the wet season. In contrast, there seems to be an increase in the number of wet days during the dry season, especially during November through January. We found that the number of dog days (above 26.7 °C) during the year and during the wet season has increased at many locations. For the post-1950 period, a widespread decrease in the daily temperature range (DTR) is observed mainly because of increased daily minimum temperature (Tmin). Although we did not attempt to formally attribute these trends to natural versus anthropogenic causes, we find that the urban heat island effect is at least partially responsible for the increase in Tmin and its corresponding decrease in DTR at urbanized stations compared with nearby rural stations. In the future, a formal trend attribution study should be conducted for the region. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim was to disclose the seasonality in the internal seiches during summer stratification in 2010 within the small, 3 km long, ellipse-shaped, temperate Lake Arendsee (Germany) with simple morphometry. We used observations of temperatures from two thermistor chains (09 April to 24 September), conductivity and temperature profiles, and wind speeds and directions (January to December). To analyze the seasonality in the periods, appearance and modal structure of the seiches, and the wind forcing, we applied spectral analysis on monthly time series of isotherms and wind speeds, and wavelet analysis on 6 month long time series of integrated potential energy and wind speeds. To determine the effect of earth's rotation on seiches, we applied two analytical models based on three-layer density stratification. Earth's rotation affected internal seiches significantly even in a small lake. That was shown by the models and the Burger number being < 1 during stratification. Vertical mode 1 Kelvin-type seiches dominated the internal seiche weather in Lake Arendsee, with their periods changing because of seasonal variations in stratification. Weak, free seiches of vertical mode 2 were amplified during three episodes: (1) in mid-summer, when their periods coincided with the inertial period at the lake's latitude, (2) in late spring, and (3) in autumn, both when their periods approached 24 h. The amplifications were caused by resonance between free seiches and wind-forced oscillations at diurnal and inertial periods. Such short-term resonance events, associated with enhanced mixing, are inherent for the seasonal stratification cycle in the most temperate lakes. [ABSTRACT FROM AUTHOR]

Recent studies from mountainous areas of small spatial extent (<2500 km2) suggest that fine-grained thermal variability over tens or hundreds of metres exceeds much of the climate warming expected for the coming decades. Such variability in temperature provides buffering to mitigate climate-change impacts. Is this local spatial buffering restricted to topographically complex terrains? To answer this, we here study fine-grained thermal variability across a 2500-km wide latitudinal gradient in Northern Europe encompassing a large array of topographic complexities. We first combined plant community data, Ellenberg temperature indicator values, locally measured temperatures (LmT) and globally interpolated temperatures (GiT) in a modelling framework to infer biologically relevant temperature conditions from plant assemblages within <1000-m2 units (community-inferred temperatures: CiT). We then assessed: (1) CiT range (thermal variability) within 1-km2 units; (2) the relationship between CiT range and topographically and geographically derived predictors at 1-km resolution; and (3) whether spatial turnover in CiT is greater than spatial turnover in GiT within 100-km2 units. Ellenberg temperature indicator values in combination with plant assemblages explained 46-72% of variation in LmT and 92-96% of variation in GiT during the growing season ( June, July, August). Growing-season CiT range within 1-km2 units peaked at 60-65°N and increased with terrain roughness, averaging 1.97 °C ( SD = 0.84 °C) and 2.68 °C ( SD = 1.26 °C) within the flattest and roughest units respectively. Complex interactions between topography-related variables and latitude explained 35% of variation in growing-season CiT range when accounting for sampling effort and residual spatial autocorrelation. Spatial turnover in growing-season CiT within 100-km2 units was, on average, 1.8 times greater (0.32 °C km−1) than spatial turnover in growing-season GiT (0.18 °C km−1). We conclude that thermal variability within 1-km2 units strongly increases local spatial buffering of future climate warming across Northern Europe, even in the flattest terrains. [ABSTRACT FROM AUTHOR]

Aims I determine the relative importance of temperature and moisture acting alone and in tandem for range contractions and expansions of mammalian species over c. 70 years. Location The contiguous United States west of the eastern border of the Rocky Mountains (103.77° W). Methods Museum records of 67 mammalian species from two time periods (1900-39 and 1970-2009), mean annual temperature and mean annual precipitation are used to model historic and modern distributions. For each era the region outside each species' range in the opposing era is assigned to zones of range limitation: temperature alone is prohibitive, moisture alone is prohibitive, both preclude the species, or both have values that alone are within the species' tolerance range but in combination are outside its climatic niche ('interaction' limitation). The relative importance of each type of limitation is estimated by their intersection with regions of range contraction and expansion. Results Averaged across species, 82 ± 3% (± SE) of the areas of contraction are now occupied by interaction limitation, and 74 ± 5% of areas expanded into were historically occupied by similar zones. In comparison, areas of range shift in which just temperature or moisture acting alone would have excluded the species comprise between only 9 and 17%, and areas in which both factors are limiting are negligible. Expansions into and contractions from regions of interaction limitation occurred more often than expected by chance given the distribution of this type of limitation in the wider study region. Main conclusions Particular combinations of temperature and moisture can interact directly or indirectly to limit species ranges even when these factors alone do not exceed species tolerances. Change in the correlation between of range-limiting factors can have as much effect on species ranges as absolute change in those factors by themselves. [ABSTRACT FROM AUTHOR]

Small dimictic Lake Plußsee in North Germany experienced major changes of the temperature and oxygen regime from 1969 to 2006, which reflected regional and large-scale changes in meteorological forcing. We used long-term weekly measurements of the lake's epilimnetic, metalimnetic, and hypolimnetic temperatures and dissolved oxygen concentrations and meteorological forcing variables to estimate long-term trends for each week. Except for large warming trends of air temperatures in the last week of April (0.14°C yr-1) and the first week of May (0.11°C yr-1), the extent of epilimnetic warming trends during the same time period (~ 0.06-0.08°C yr-1) was also caused by a cumulative effect resulting from an earlier onset of stratification. Negative hypolimnetic temperature trends at the same time (~ 0.01°C yr-1) also resulted from an earlier onset of stratification and increased water-column stability in spring. In summer and autumn, large increases in epilimnetic temperature and water-column stability were also affected by a shift of the timing of the yearly maxima of epilimnetic temperatures and water-column stability, which resulted in a later breakdown of stratification. This annual pattern of long-term trends of epilimnetic and hypolimnetic temperatures agrees with models driven by the expected increase of air temperatures due to anthropogenic greenhouse gases. Due to a prolonged stratification period, oxygen concentrations during the last weeks of the stratified period were lower, although oxygen concentrations in the water column increased within the first weeks of stratification. [ABSTRACT FROM AUTHOR]

Air temperature represents a key parameter for snow hydrology, as it controls the precipitation phase, as well as snow accumulation and snowmelt. Hydrological modelling in mountain regions like the Alps needs high-resolution temperature fields as input, preferably at sub-daily time steps. The estimation of such temperature fields is challenging due to the spatio-temporal variability of environmental lapse rates (i.e. the decreasing of temperature with altitude) associated to complex topography. In this study, 10 years (2000-2009) of data from about 200 temperature stations were interpolated at 0, 6, 12 and 18 h Universal Time Coordinated (UTC) over a 1-km resolution grid covering a window of 71 500 km2 in the Northern French Alps. Three different kriging methods were tested. Kriging with elevation as external drift gave the best results in terms of mean absolute error, root mean square error and kriging standard deviation. Adding potential solar radiation as an additional external variable did not improve significantly the interpolation results. Prediction errors showed dependence on elevation and season, as well as on the time of interpolation, with globally better results in summer and daytime than in winter and night-time. Despite some shortcomings that are discussed in the paper, the interpolated temperature fields look promising for further snowmelt and snow cover dynamics modelling studies. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aim To test the ability of biological traits to predict climate-related changes in geographical ranges of running-water invertebrates. Location The Australian state of New South Wales and the Australian Capital Territory. Methods I analysed data from 8928 biomonitoring samples collected during a 16-year period of generally rising air temperatures and declining precipitation. I used quantile regression to test for expansions and contractions on the climatically cooler, warmer, drier and wetter edges of the ranges of 120 invertebrate taxa, and correlated these shifts with the traits of thermophily (degree of preference for high versus low temperature) and rheophily (preference for flowing versus still water). Results The most commonly inferred range shifts were cool-edge expansion plus warm-edge contraction (71 taxa) and wet-edge expansion plus dry-edge contraction (71), but contractions from both cool and warm extremes (36) and from both dry and wet extremes (28) were also frequent. High-temperature preference was associated with cool-edge expansion and low-temperature preference with wet-edge expansion and contraction from all other extremes. A preference for flow was associated with wet-edge expansion and dry-edge contraction. Main conclusions Trait analysis has potential for predicting which species will expand their ranges and which will contract, but needs to be coupled with assessment of how the landscape provides each species with opportunities to track or avoid climate change. Improved quantification of climatically relevant traits and integration of trait analysis with species distribution modelling are likely to be beneficial. [ABSTRACT FROM AUTHOR]

The main objective of this study was to analyse the trends in 20 annual extreme indices of temperature and precipitation for Utah, USA. The analyses were conducted for 28 meteorological stations, during the period from 1930 to 2006, characterized by a long-term and high-quality dataset. The software used to process the data was the RClimdex 1.0. The analyses of extreme temperature indices have identified an increase in air temperature in Utah during the last century. Meanwhile, the analyses of precipitation indices showed a large variation throughout the studied area and time period, and, in general, with few statistically significant trends. Thus, it was not possible to conclude that significant changes in precipitation have occurred in this region over the last century. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The article discusses a study on the equivalent temperature and temperature from 1979-2005 and its relation to land cover types in the U.S. It says that study used the data from National Centers for Environmental Prediction North American Regional Reanalysis, Advanced Very High Resolution Radiometer (AVHRR), National Land Cover Database, and Normalized Difference Vegetation Index (NDVI). Results show that land cover types affect moisture availability and temperature in lower atmosphere.

Thermal–mechanical fatigue (TMF) testing is a good method to decrease the number of isothermal tests for non-isothermal behaviour laws identification. Based on experimental results of the TMF Standard European Working Group, this study aims to investigate the impact of thermal gradients on mechanical heterogeneity within the gage length specimen. The quality of the TMF test is examined by an energy criterion related to error bounds for nonlinear behaviour. A sensitivity analysis is then made for a given behaviour law identified on a TMF test to answer to the above question. Moreover the geometric instability phenomenon, already noticed by Sheffler and Coffin, is modelled herein. [ABSTRACT FROM AUTHOR]

Refuges provide shelter from predators, and protection from exposure to the elements, as well as other fitness benefits to animals that use them. In ectotherms, thermal benefits may be a critical aspect of refuges. We investigated microhabitat characteristics of refuges selected by a heliothermic scincid lizard, Carlia rubrigularis, which uses rainforest edges as habitat. We approached lizards in the field, simulating a predator attack, and quantified the refuge type used, and effect of environmental temperatures (air temperature, substrate temperature and refuge substrate temperature) on the amount of time skinks remained in refuges after hiding (emergence time). In respone to our approach, lizards were most likely to flee into leaf litter, rather than into rocks or woody debris, and emergence time was dependent on refuge substrate temperature, and on refuge substrate temperature relative to substrate temperature outside the refuge. Lizards remained for longer periods in warmer refuges, and in refuges that were similar in temperature to outside. We examined lizard refuge choice in response to temperature and substrate type in large, semi-natural outdoor enclosures. We experimentally manipulated refuge habitat temperature available to lizards, and offered them equal areas of leaf litter, woody debris and rocks. When refuge habitat temperature was unmanipulated, lizards (85%) preferred leaf litter, as they did in the field. However, when we experimentally manipulated the temperature of the leaf litter by shading, most skinks (75%) changed their preferred refuge habitat from leaf litter to woody debris or rocks. These results suggest that temperature is a critical determinant of refuge habitat choice for these diurnal ectotherms, both when fleeing from predators and when selecting daytime retreats. [ABSTRACT FROM AUTHOR]

The Earth's atmosphere has a natural greenhouse effect, without which the global mean surface temperature would be about 33 °C lower and life would not be possible. Human activities have increased atmospheric concentrations of carbon dioxide, methane, and other gases in trace amounts. This has enhanced the greenhouse effect, resulting in surface warming. Were it not for the partly offsetting effects of increased aerosol concentrations, the increase in global mean surface temperature over the past 100 years would be larger than observed. Continued surface warming through the 21st century is inevitable and will likely have widespread ecological impacts. The magnitude and rate of warming for the global average will be largely dictated by the strength and direction of climate feedbacks, thermal inertia of the oceans, the rate of greenhouse gas emissions, and aerosol concentrations. Because of regional expressions of climate feedbacks, changes in atmospheric circulation, and a suite of other factors, the magnitude and rate of warming and changes in other key climate elements, such as precipitation, will not be uniform across the planet. For example, due to loss of its floating sea-ice cover, the Arctic will warm the most. [ABSTRACT FROM AUTHOR]

The article focuses on the analysis of the skills of seven regional climate models (RCM) in the reproduction of mean daily temperatures for the Central England region. It notes that three airflow indices were used during the examination of RCM's ability to reproduce. Comparison among the frequency distribution of each index, the relationships between the daily airflows indices and temperature, as well as the ability of models to reproduce is discussed.

The article examines the factors contributing to the observed tendencies in the maximum and minimum temperatures in Zacatecas, Mexico. Results of the environmental and atmospheric analysis reveal continued changes in the climate that can be associated with warming caused by the increase in greenhouse gases. The global warming resulted in the diurnal temperature range (DTR) is caused by a faster rate of increase in minimum temperatures. Analysis of the data gathered from the region shows that maximum and minimum temperatures are partly linked to the state of the low frequency variability of large scale atmospheric flow patterns.

The article discusses the use of a model of coral and symbiont ecological dynamics and symbiont evolutionary dynamics to examine the coral response to climate change. The model without variation in symbiont thermal tolerance can predict collapse of coral reef within decades under multiple future climate scenarios. Meanwhile, the model with genetic or community-level variation in symbiont thermal tolerance can predict survival of coral reef given the low greenhouse gas emissions. In this connection, greenhouse gas emissions have a significant impact on the future of coral reef.

The article discusses a study which presented tools to generate synthetic sequences of half-hourly temperatures with similar statistical characteristics to observe historical data. A combination of daily and half-hourly temperature models were used to generate temperatures, which account for intra-day and intra-year seasonality and short- and long-term serial correlations. Discrepancies in the distribution of the half-hourly temperatures between the three summer months were showed by exploratory analysis.

The article discusses an equilibrium and kinetic study on the use of activated carbons as adsorbents in removing acid blue 15 (AB-15) from aqueous solution. Experimental parameters such as temperature, adsorbent dosage, pH, initial dye concentration and contact time were evaluated with the use of batch adsorption techniques. It was found that the optimum conditions for the removal of AB-15 is a pH level of 3, adsorbent dosage of 3 g/L and an equilibrium time of four hours at 30°C. Also, the adsorption of AB-15 onto the adsorbent was found to be directly related to the dosage. Moreover, the Langmuir isotherm was observed to fit data better than the Freundlich and Temkin isotherms.

Sorption isotherms of intermediate moisture content (IMC) products are essential to predict shelf-life of packaged moisture-sensitive product by modelling moisture uptake during storage and distribution. The effect of temperature and initial moisture content (MC) of IMC banana on the relationship between MC and water activity were investigated. Raw bananas were dried in a tunnel dryer at 2% relative humidity (RH), 70 °C, and a 3.2 ± 0.2 m s–1 air velocity. Drying procedure was carried out a number of times until various IMC levels were obtained (5%, 14%, 22% and 33% db for banana). Sorption isotherms of bananas were determined at 10, 20, 30 and 40 °C. The initial MC of IMC banana had no significant effect on the relationship between MC and water activity according to statistical analysis. All the sorption curves were found to be Type II. BET, GAB, modified GAB, Oswin, Halsey and modified Freundlich models were fitted to the data and it was found that the best results were obtained with a modified Freundlich equation. A secondary modified Freundlich model was built accounting for the effect of aw and temperature on the sample MC. [ABSTRACT FROM AUTHOR]

The article reports on the mass balance and sensitivity to climate of Kersten Glacier, a slope glacier on the southern part of Kilimanjaro Mountain in Tanzania. Measurements obtained are used to run a physically-based mass balance model for the period of February 2005 to January 2006. Experiments showed that glacier mass balance is 2 to 4 times more sensitive to precipitation change than to air temperature change. Results suggest that a regional moisture projection for the 21st century must be integrated to a physically-based prediction of glacier retention on Africa's highest mountain.

The article reports on the assessment of trends in minimum and maximum surface air temperature, its indicators, and the diurnal thermal range (DTR) trends in southern Brazil for the period of 1960-2002. Observations suggest that most meteorological stations show steep increases in the night-time temperature and slight increases in the daytime. In addition, warming trends are stronger during winter as compared to summer. DTR shows negative trends from 1960-2002 in most of the region, and these trends are largely due to the greater increase in night-time temperatures rather than daytime.

The article examines the impact of different averaging algorithms on daily maximum and minimum temperature. The authors found out that some surface climate networks produced a systematic warming or cooling bias in daily maximum or minimum temperature observation which led to resulting biases making the diurnal temperature range more biased in extreme climate studies, in comparison to the longest recorded and standard liquid-in-glass maximum and minimum thermometers. They recommend providing an accurate description of daily maximum and minimum temperatures to prevent the uncertainties in the observed climatology.

The article investigates the relaxation behaviors of isotactic, atactic and syndiotactic poly(methyl methacrylate) (PMMA) monolayers in three different temperatures at the air/water interface. According to the authors, pressures at inflection points of pi-A isotherms decreases when temperature increases, while the collapse pressure also declines when the temperature is increased. They reveal that the PMMA stereoisomers' relaxation process can be characterized using a model that considers nucleation and growth mechanisms.

This article examines the absorption and diffusion coefficients of pure carbon dioxide and nitrogen as a function of temperature and pressure for poly(dimethyl, methylphenyl siloxane). It shows that the product of diffusivity and solubility coefficient is the permeability of a component diffusing through a membrane. There were five different temperatures in which the absorption isotherms were obtained. The Flory-Rehner expression was used to model the absorption isotherms. It concludes that the change in carbon dioxide permeability as a function of pressure is caused by changes in the diffusion coefficient.

Objective: The present study aimed to determine the plausibility of forecasting the outbreak of diseases based on the weather by analysing the impact of atmospheric temperature and humidity on the occurrence of different diseases. Methods: The subjects of the present study were the 30 434 patients who visited the ED in 1 year from 1 February 2005 to 3 February 2006. The present study analysed the correlation between the daily number of patients who suffered from 22 types of traumatic and non-traumatic diseases and the data on atmospheric temperature and humidity provided by the Korea Meteorological Administration. Results: With traumatic disease, the occurrence tended to increase in proportion to the rise in temperature and humidity; whereas with non-traumatic disease, the occurrence tended to increase according to the rise in temperature, irrespective of humidity changes. The research on the impact of atmospheric temperature and humidity on different diseases revealed a high level of distribution of most diseases in an environment with high temperature and humidity. However, in the case of pulmonary diseases and trauma to multiple body regions, the occurrence increased in environments with low temperature and high humidity for pulmonary diseases, and with low temperature and low humidity for trauma to multiple body regions. Conclusion: Most diseases tend to increase in proportion to the rise in atmospheric temperature whereas being less affected by humidity. However, an increase in humidity in an optimum range of atmospheric temperature (12°C or higher) triggers an increase in the occurrence of diseases. [ABSTRACT FROM AUTHOR]

The article cites a study which organizes 43 monthly series of maximum and minimum temperatures which are all available Spanish long-term series which are intended to identify the regional differences in the thermal evolution in Spain. It also presents an analysis of the temperature evolution in the Iberian Peninsula and Madrid. It is determined that the data on homogenized Spanish maximum and minimum temperature series is useful in improving the perspectives to analyze the regional temperature changes in Spain and the basis for the discussion of these changes in the global context.

The article presents a study which aims to compare the time-series analyses of urban and rural temperature trends in proximity to the most populous metropolitan areas of the U.S. It also examines the temperature data from the urban and proximate rural stations for 50 large metropolitan areas in the U.S. to determine the mean decadal rate of change in urban temperatures, rural temperatures, as well as heat island intensity between 1951 and 2000. The study reveals that the mean decadal rate of change in the heat island intensity of large cities in the U.S. over the five decades is 0.05 degree Celsius and indicates a division concerning the temperature trends between cities in the northeastern and southern regions in the U.S.

The article investigates the number of days with snow cover at 268 Alpine climate stations during winter period, from 1961-2000, and its relation with the mean winter temperature over Europe. A physical-statistical model of snow duration, along with hyperbolic tangent function to generate the logistic curve for the snow-temperature relationship were used. Results of the study proves to be valid for the Alpine region and independent against a linear temperature trend. Findings reveal that the snow-temperature sensitivity in the Alpine region is in accordance with earlier estimates for Austria and Switzerland.

The article offers information on half-century seasonal relationships between the Southern Hemisphere Annular Mode (SAM) and Antarctic temperatures. It is posed that a general pattern of positive correlations between the strength of the SAM and temperatures in the northern Antarctic Peninsula (East Antarctica) is manifested to be valid for the last half-century, but differences are noted between the seasons. Moreover, SAM-temperature correlations are stronger across Antarctica in austral summer and autumn.

This article presents a study regarding the trends in extreme daily temperature and precipitation near Lake Hövsgöl, Mongolia. From 1963 to 2002, a long-term set of daily maximum and minimum temperature and precipitation data are analyzed for the Lake Hövsgöl area in Mongolia. It examines eight indices of extreme precipitation and six indices of extreme temperature. Results revealed that climate conditions over northern Mongolia are changing as showed by a warming trend identified during the research period.