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Copyright of Journal of Tikrit University for Humanities is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Leiper's (1990) tourism attraction system is used to explore the roles of sport as a tourist attraction. The impact of changes to sport tourism attractions is then considered in the context of the spatial and temporal dimensions of tourism. This approach is applied to the introduction of Rugby Super 12 in New Zealand. Selected sport and tourism administrators in the Otago Highlanders franchise area were interviewed to obtain their views of the tourism impacts of the introduction of Rugby Super 12 within the region. Findings identified a wide range of spatial and temporal impacts including new travel flows and altered tourism seasons. The discussion of these findings highlights the implications of the study for sport and tourism managers and emphasizes the merit of using an attraction approach in sport tourism research. [ABSTRACT FROM AUTHOR]

Résumé Le gnomon est le plus ancien instrument d'astronomie, puisque son utilisation est attestée dès le deuxième millénaire av. J.–C. Il a permis de déterminer, pour les Anciens, les paramètres fondamentaux de la Terre, comme ses mouvements en relation avec le Soleil ; son usage était généralisé dans de nombreuses civilisations. Il a sans cesse connu des améliorations, jusqu'à atteindre une précision de quelques secondes de degrés avec les méridiennes intérieures construites en Europe aux XVIIe et XVIIIe siècles. Plus remarquable encore est son utilisation au XXIe siècle au cours de missions spatiales. Abstract Gnomon is the oldest astronomic instrument, as its use is attested as early as the second millenium B.C. It allowed the ancients to ascertain the Earth's main basic parameters, such as its movement relatively to the Sun. The use of gnomon was generalized in numerous antique civilizations. It was constantly improved up to reaching a precision of a few seconds of degree for the inner meridians built in Europe during the 17th and 18th centuries. More remarkably, it was used during the 21st-century space missions. [ABSTRACT FROM AUTHOR]

The Mississippi‐Atchafalaya River System (MARS) is an important source of freshwater and terrigenous material to the Gulf of Mexico. We used sea surface salinity (SSS) measurements from the Soil Moisture Active Passive (SMAP) satellite and terrigenous dissolved organic carbon (tDOC) from Moderate Resolution Imaging Spectroradiometer (MODIS) to describe the MARS plume seasonality and interaction with the Gulf circulation. Our analyses revealed good agreement between SMAP and in situ salinity for S > 31, and that satellite‐derived tDOC can serve as a useful tracer for the river plume. A boundary detection algorithm was used to quantify the frequency of plume occurrence in the Gulf for the last 15 years. The MARS plume has its maximum offshore extension during summer, retracting to closer to shore during fall/winter. Variability at monthly time scales is controlled by river discharge and alongshore winds, which explain up to 60% of the local variance in the frequency of plume occurrence near the shelfbreak. Maximum variability in plume extension is found to the east of the Mississippi River Delta due to wind reversals that generally occur during summer. The combined use of SMAP salinity and MODIS‐tDOC allowed for a detailed view of anomalous events in 2015 and 2016, when the MARS plume was transported for 350 km from the coast due to interactions with the Loop Current and with dipole eddies. While SMAP observations allow for tracking the river plume even in cloudy conditions, high‐resolution MODIS data allow for a more accurate characterization of sharp fronts and of the width of river‐influenced filaments. Plain Language Summary: The Mississippi‐Atchafalaya River System (MARS) is an important source of freshwater, nutrients, carbon and sediments to the Gulf of Mexico. Here we use satellite observations of surface salinity and of dissolved organic carbon of terrigenous origin to describe the behavior of the MARS plume and its interaction with the Gulf circulation for the last 15 years. We show that the MARS plume is transported offshore during summer and toward the coast during fall/winter and that this seasonal variability is controlled by the interaction between river discharge and winds. In 2015 and 2016, the MARS plume was transported for 350 km from the coast due to interactions with the large‐scale circulation in the Gulf. While salinity from satellite observations allows us to track the river plume even in cloudy conditions, tDOC provides a more accurate characterization of sharp fronts and of the width of river‐influenced filaments. Key Points: Soil Moisture Active Passive (SMAP) salinity and MODIS‐Aqua combined provide improved description of Mississippi River plume variabilityMississippi River plume extends offshore during summer and retracts during fall/winterWinds and discharge are the dominant mechanisms controlling the Mississippi River plume on monthly time scale [ABSTRACT FROM AUTHOR]

The East Greenland Current is a major pathway for freshwater export from the Arctic Ocean and for the transport of dense overflow waters toward the North Atlantic. We use moored measurements from the East Greenland Current north of Denmark Strait from October 2011 to April 2012 to analyze the wind‐driven variability of the shelfbreak branch of this current system. By combining the moored data with atmospheric reanalysis data we found that coastal upwelling and downwelling take place in the shelfbreak East Greenland Current throughout winter. In total, upwelling and downwelling events occur around five times per month, and these events modulate the volume transport and redistribute water masses. Specifically, we find that upwelling may lead to a deposition of dense water masses on the shelf and to an offshore transport of freshwater, while downwelling events are associated with a considerable increase in along‐stream freshwater transport. Based on wind patterns and wind‐driven ocean variability along the east Greenland coast, the integrated effect of these episodes is expected to be substantial. Plain Language Summary: The East Greenland Current contributes to the large‐scale ocean circulation in the North Atlantic. This current transports both freshwater and sea ice southward from the Arctic Ocean and supplies water masses to the deep circulation in the Atlantic Ocean. We use measurements from the East Greenland Current between Iceland and Greenland from October 2011 to April 2012 to analyze the wind‐driven variability in one branch of this current system. By combining the oceanographic data with atmospheric data we found that the wind induced vertical motions in the shelfbreak East Greenland Current throughout winter. In total, these wind‐driven events occur around five times per month and lead to a considerable modulation of the volume transport and a redistribution of water masses both vertically and horizontally. The integrated effect of such episodes is expected to be substantial due to the large region influenced by the wind conditions favorable for this type of oceanic response. Key Points: Mooring data from winter 2011–2012 show that upwelling and downwelling take place in the shelfbreak East Greenland CurrentUpwelling events may lead to a deposition of dense water masses on the shelfDownwelling events are associated with a considerable increase in freshwater transport [ABSTRACT FROM AUTHOR]

A simple closed contour object identification scheme has been applied to the zonal mean monthly mean zonal wind fields from nine global reanalysis data sets for 31 years of the satellite era (1979-2009) to identify objects corresponding to westerly jet streams. The results cluster naturally into six individual jet streams but only the mid-latitude upper-tropospheric jets are considered here. The time series of the jet properties from all reanalyses are decomposed into seasonal means and anomalies, and correlations between variables are evaluated, with the aim of identifying robust features which can form the basis of evaluation metrics for climate model simulations of the twentieth century. There is substantial agreement between all the reanalyses for all jet properties although there are some systematic differences with particular data sets. Some of the results from the object identification applied to the reanalyses are used in a simple example of a model evaluation score for the zonal mean jet seasonal cycle. [ABSTRACT FROM AUTHOR]

High-resolution (930 samples) magnetic susceptibility (MS) and anhysteretic remanent magnetization (ARM) analyses were conducted on the ~ 49 m thick Middle Permian Maokou Formation at Dukou, South China. Spectral analysis of covariant MS and ARM series reveal Milankovitch cycles with eccentricity, obliquity, and precession. A 5.7 myr floating 405 kyr eccentricity cycle-calibrated astronomical time scale was constructed and used as a geochronometer for estimating the durations of the conodont zones. The results indicate that the durations of the Jinogondolella postserrata , J. altudaensis , J. prexuanhanensis , and J. xuanhanensis conodont zones were 490 kyr, 560 kyr, 820 kyr, and 750 kyr, respectively. The 405 kyr-calibrated MS and ARM series also show prominent ~ 1 myr cyclicity, which may correspond to the secular frequencies of Earth and Mars, s 4 –s 3 , in the Middle Permian. The early Capitanian time interval was synchronous with the Kamura cooling event, and the accentuated obliquity cycling may signal ice-sheet expansion. The modulations of the obliquity have a close relationship with third-order eustatic sequences of the Wordian and Capitanian stages, suggesting a glacioeustatic origin during the Middle Permian. [ABSTRACT FROM AUTHOR]

The MACE (Major Atmospheric Cherenkov Experiment) is an upcoming Very High Energy (VHE) γ -ray telescope, based on imaging atmospheric Cherenkov technique, being installed at Hanle, a high altitude astronomical site in Ladakh, India. Here we present Monte Carlo simulation studies of trigger rates and threshold energies of MACE in the zenith angle range of 0°–60° for on-axis γ -ray coming from point source and various cosmic ray species. We have simulated the telescope’s response to γ -rays, proton, electron and alpha initiated atmospheric Extensive Air Showers (EAS) in the broad energy range of 5 GeV to 20 TeV. For γ -rays we consider power law and log parabolic spectra while other particles are simulated with their respective cosmic ray spectrum. Trigger rates and threshold energies are estimated for the trigger configuration of 4 Close Cluster Nearest Neighbour(CCNN) pixels as implemented in MACE hardware, in combination with single channel discriminator threshold ranging from 6–10 photo electrons (pe). We find that MACE can achieve the γ -ray trigger energy threshold of ∼ 17 GeV (4 CCNN, 9 pe) at 0° zenith angle for power law spectrum. The total trigger rate at 0° zenith is expected to be ∼650 Hz, with protons contributing ∼ 80% to it. For the zenith range of 0°-40° we find that the telescope can achieve γ -ray trigger threshold energies of ∼22 GeV at 20° zenith angle and ∼40 GeV at 40° zenith angle. Integral rates are also almost constant for this zenith angle range. At zenith angle of 60°, trigger energy threshold increases to ∼173 GeV and total integral rate falls down to ∼305 Hz. [ABSTRACT FROM AUTHOR]

One step toward improving our understanding of all the possible factors and environmental features that are related to waterspout formation is to establish continuous data collection and to provide a preliminary climatology of waterspouts in a region. A waterspout survey was launched on the official Web site of the Croatian Meteorological and Hydrological Service during late spring 2011. This survey helped create an extensive waterspout database, which recorded a total of 359 waterspout events from 2001 to 2013. Because most reports regarding waterspouts were obtained from unofficial sources, we underline the need for new ways to observe relatively short, rare and spatially limited weather events such as waterspouts. The analysis of the collected data in this work includes the spatial and temporal distribution of the waterspout events per year, season, month and time of day. 'Non-thunderstorm' and 'thunderstorm' waterspouts were separated, and the absolute frequencies of five synoptic types that were relevant to waterspout development are shown. Finally, the thermodynamic environment was analyzed with the help of radio-sounding data. The results show that waterspout events are equally distributed along the eastern part of the Adriatic coast. However, an evident connection exists between the number of spotted events and the locations of more densely populated areas, i.e., big towns or tourist destinations. Waterspouts are more frequent during the summer months, especially during August, and 51.5 % of the recorded events were related to thunderstorms. Most of them were spotted during the day, whereas only two were spotted during the night; waterspouts developed more often during the morning hours. The synoptic environment dominated by a southwesterly flow has proven to be the most supportive for the development of waterspouts. [ABSTRACT FROM AUTHOR]

The study examines aerosol loading in different vertical layers of the atmosphere and explores the role of atmospheric circulation parameters in vertical distribution of aerosols and in its seasonal variability. Aerosol vertical distribution over the globe is examined, using long term satellite observations, by considering aerosol loading in different layers of atmosphere upto ∼6 km altitudes from surface and fractional contribution of each of these layers to total columnar aerosol loading. Aerosols are observed residing close to the surface in most of the oceanic environments, except over certain regions which are in the close proximity of continents where upper level winds are conducive for long range aerosol transport. In contrast, considerable vertical spread in aerosol distribution with strong seasonal variability, minimum occurring in winter months and maximum in summer, is observed over the continental regions. Vertical spread in aerosol distribution is observed highest over north eastern and north western parts of Africa during northern hemispheric summer, when the convection activity peaks over these regions due to large solar insolation and associated surface heating. Seasonal variation of aerosol vertical spread over both of these regions is observed in phase with variation in atmospheric convergence and vorticity. During summer months, when the aerosol vertical spread is highest, strong surface level convergence and associated cyclonic vorticity is observed along with an upper level (700–600 hPa) divergence. The surface level convergence and upper level divergence together induce an upward flow of air which carries aerosols from ground to higher altitudes. This mechanism of aerosol vertical transport is further corroborated through the correlation and regression relations of surface convergence/vorticity with aerosol loading above different elevations and hence the study reveals role of circulation parameters in aerosol vertical distribution. [ABSTRACT FROM AUTHOR]

Medical observations show that the level of pollinosis increased by 34.6% in central Russia in 2005-2012. This paper presents the results of 6-year pollen monitoring carried out with a Hirst-type pollen trap (Burkard Manufacturing Co. Ltd) between 2010 and 2015 in Perm Krai (Russia). Usually, sensitization of allergic people occurs in three periods: (i) spring due to the pollen of Betula, (ii) early summer due to Poaceae pollen, and (iii) late summer as a result of Artemisia pollen. Betula pollen, which is dominant (26.9-65.2% of total pollen counts), is recorded in large numbers in the period of flower- ing and occasionally during the entire period of pollination. Among herbaceous plants, the pollen of Poaceae, Urticaceae and Artemisia dominates in airborne pollen. The concentration of allergenic pollen grains in the air of Perm Krai is lower than in other European geographical regions. [ABSTRACT FROM AUTHOR]

The paper refers to the estimation of Poaceae pollen seasons in Poland in selected areas. The aim of the study was to present the long-term variability of the start, end and duration of grass pollen seasons and the seasonal pollen index (SPI) in Poland against a background of the meteorological conditions over pollen seasons. The study was performed in eight Polish cities in 1992-2014 (the common seasons were 2003-2012). Pollen season start was relatively stable in the studied period, the seasons began about the 10th of May, a bit earlier in the south part of Poland. Pollen season ends were more changeable in comparison to the season start and fluctuated from the middle of July to the middle of September. SPI clearly depended on temperature and precipitation in April-August. Daily maximum pollen concentrations were achieved between the end of May and the first decade of July and no evident relationship between this day and weather conditions was found, apart from 2004. [ABSTRACT FROM AUTHOR]

Copyright of Llull: Revista de la Sociedad Espanola de Historia de las Ciencias y de las Tecnicas is the property of Sociedad Espanola de Historia de las Ciencias y de las Tecnicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fields of Astrostatistics and Astroinformatics are vital for dealing with the big data issues now faced by astronomy. Like other disciplines in the big data era, astronomy has many V characteristics. In this paper, we list the different data mining algorithms used in astronomy, along with data mining software and tools related to astronomical applications. We present SDSS, a project often referred to by other astronomical projects, as the most successful sky survey in the history of astronomy and describe the factors influencing its success. We also discuss the success of Astrostatistics and Astroinformatics organizations and the conferences and summer schools on these issues that are held annually. All the above indicates that astronomers and scientists from other areas are ready to face the challenges and opportunities provided by massive data volume. [ABSTRACT FROM AUTHOR]

Seasonality of sea surface temperature (SST) predictions in the tropical Indian Ocean (TIO) was investigated using hindcasts (1982-2009) made with the NCEP Climate Forecast System version 2 (CFSv2). CFSv2 produced useful predictions of the TIO SST with lead times up to several months. A substantial component of this skill was attributable to signals other than the Indian Ocean dipole (IOD). The prediction skill of the IOD index, defined as the difference between the SST anomaly (SSTA) averaged over 10°S-0°, 90°-110°E and 10°S-10°N, 50°-70°E, had strong seasonality, with high scores in the boreal autumn. In spite of skill in predicting its two poles with longer leads, CFSv2 did not have skill significantly better than persistence in predicting IOD. This was partly because the seasonal nature of IOD intrinsically limits its predictability. The seasonality of the predictable patterns of the TIO SST was further explored by applying the maximum signal-to-noise (MSN) empirical orthogonal function (EOF) method to the predicted SSTA in March and October, respectively. The most predictable pattern in spring was the TIO basin warming, which is closely associated with El Niño. The basin mode, including its associated atmospheric anomalies, can be predicted at least 9 months ahead, even though some biases were evident. On the other hand, the most predictable pattern in fall was characterized by the IOD mode. This mode and its associated atmospheric variations can be skillfully predicted only 1-2 seasons ahead. Statistically, the predictable IOD mode coexists with El Niño; however, the 1994 event in a non-ENSO year (at least not a canonical ENSO year) can also be predicted at least 3 months ahead by CFSv2. [ABSTRACT FROM AUTHOR]

The observation that the shadows of objects change during the course of the day and also for a fixed time during a year led curious minds to realize that the Sun could be used as a timekeeper. However, the daily motion of the Sun has some subtleties, for example, with regards to the precise time at which it crosses the meridian near noon. When the Sun is on the meridian, a clock is used to ascertain this time and a vertical stick determines the angle the Sun is above the horizon. These two measurements lead to the construction of a diagram (called an analemma) as an extremely useful resource for the teaching of astronomy. In this paper we report on the construction of this diagram from roughly weekly observations during more than a year. [ABSTRACT FROM AUTHOR]

ABSTRACT Theoretical probability distributions of seasonal rainfall totals have potential applications in fitting models and generating synthetic data. One of the major challenges in fitting distributions for seasonal rainfall from countries like Australia is that the data differ significantly for various seasons across stations. The wet stations may possess strictly positive rainfall amounts only, whereas dry stations may observe seasons with no rainfall. Furthermore the data ranges from approximately symmetric to highly skewed. We explore fitting distributions from the Tweedie family of distributions to model seasonal rainfall. The Tweedie family of distributions includes continuous-symmetric (normal), continuous-skewed (gamma) and mixture-type (Poisson-gamma, P-G) distributions. This study analysed seasonal rainfall totals from 989 Australian stations with data for about 100 years. For various seasons, within the Tweedie family the P-G distributions were optimal for about 50% of stations, the gamma distributions were near-optimal for approximately 40% and the normal distributions were near-optimal elsewhere. Most of the stations where the gamma distributions are near-optimal are concentrated on the Australian coastline. The quantile-quantile ( QQ) plots indicate that the models fit well to the seasonal rainfall totals of selected stations. Almost everywhere, various statistics of observed seasonal rainfall are within the empirical 95% confidence intervals of the respective statistics of simulated data using the Tweedie models. The model performs better in modelling extremely high rainfall events (95th percentiles) than the extremely low (5th percentiles) rainfall events. In addition, the P-G distribution within the Tweedie family models the probability of no rainfall and, for about 97% of stations, the observed probability of no rainfall is within the 95% confidence interval of the simulated probability of no rainfall. The ability of the Tweedie models to simulate the extreme rainfall amounts and the probability of no rainfall can be useful in drought monitoring and in water resources planning and management. [ABSTRACT FROM AUTHOR]

Patterns of root traits among different root orders and their variation across seasons are of considerable importance for soil resource acquisition and partitioning in forest ecosystems. We evaluated whether morphological, anatomical and biochemical traits varied among root orders of Quercus robur (L.) sampled across spring, summer and fall seasons and growing in two different soil types with contrasting site fertility. We found no consistent differences in root diameter and specific root length in relation to soil type or growing season. There was, however, a strong seasonal variation in patterns of nitrogen (N) concentration among root orders. During spring and summer, N concentration was highest in the most distal, absorptive portion of the root system. At the end of the growing season, we observed a sharp decline in the N concentration of these lower-order, absorptive roots and an increase in N concentration of the higher-order, transport roots. The specific mechanisms driving the seasonally changing N concentration remain unclear but are likely related to different functions of lower-order roots for absorption and higher-order roots for structure and storage. Future work should identify how common the observed seasonal changes in N concentration are across species and determine what specific environmental cues plants or roots use to trigger shifts in resource allocation within the root branching hierarchy. [ABSTRACT FROM AUTHOR]

In Mediterranean climates, the season of water availability (winter) is out of phase with the season of light availability and atmospheric moisture demand (summer). We investigate the seasonality of evergreen tree transpiration in a Mediterranean climate, using observations from a small (4000 m2), forested, steep (32°) hillslope, in the northern California Coast Range. We analyze 3 years of half-hourly measurements from 39 sap flow sensors in 26 trees, six depth profiles of soil moisture measured by TDR, and spatially distributed measurements of micrometeorology from five locations. The sap flow measurements show that two common evergreen tree species have different seasons of peak transpiration. Douglas-firs ( Pseudotsuga menziesii) maintain significant transpiration through the winter rainy season and transpire maximally in the spring, followed by a sharp decline in transpiration in the summer dry season. Pacific madrones ( Arbutus menziesii), and to a lesser extent other broadleaf evergreen species ( Quercus wislizeni, Notholithocarpus densiflorus, Umbellularia californica), in contrast, transpire maximally in the summer dry season. The seasonal patterns are quantified using principal component analysis. Markov chain Monte Carlo estimation of response to environmental variables shows that the difference in transpiration seasonality arises from different sensitivities to atmospheric evaporative demand and root-zone moisture. The different sensitivities to atmospheric evaporative demand also create species differences in transpiration variability at synoptic time scales. Using the sap flow measurements and a regional forest inventory, a bottom-up regional transpiration estimate is constructed. The estimate suggests that sensitivity of Douglas-fir transpiration to water stress suppresses dry season evapotranspiration at the regional scale. [ABSTRACT FROM AUTHOR]

Including satellite-derived snow cover data for hydrologic model calibration can be a good way to improve model internal consistency. This study applied a multiobjective genetic algorithm to characterize the trade-off curve between model performance in terms of discharge and snow cover area (SCA). Using a Monte Carlo-based approach, we further investigated the additional information content of an increasing number of SCA scenes used in the calibration period. The study was performed in six snowmelt-dominated headwater catchments of the Karadarya Basin in Kyrgyzstan, Central Asia, using the hydrological model WASA and snow cover data from four melt seasons retrieved from AVHRR (Advanced Very High Resolution Radiometer). We generally found only small trade-offs between good simulations with respect to discharge and SCA, but good model performance with respect to discharge did not exclude low performance in terms of SCA. On average, the snow cover error in the validation period could be reduced by very few images in the calibration period. Increasing the number of images resulted in only small further improvements. However, using only a small number of images involves the risk that these particular images cause the selection of parameter sets which are not representative for the catchment. It is therefore advisable to use a larger number of images. In this study, it was necessary to include at least 10-16 images. [ABSTRACT FROM AUTHOR]

Several studies have documented the poleward shift of the midlatitude westerly jet of the Southern Hemisphere during the last decades of the twentieth century, mainly during the warm season. In this work the consistency between this change and the seasonal changes in frontal activity and precipitation are explored. The authors also attempt to identify the correlation between frontal activity and precipitation changes. Frontal activity is defined using the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) dataset for the period 1962-2001 as the temperature gradient times the relative vorticity at 850 hPa. Considering cyclonic systems only, an enhancement of the frontal activity at high latitudes in the last two decades is apparent. However, the pattern of frontal activity change is not zonally symmetric, with the zonal asymmetries consistent with the climate change signal of the zonal anomaly of the 300-hPa geopotential height. The pattern of precipitation change, showing midlatitude drying and high-latitude moistening, is consistent with the pattern of the frontal activity change, explaining to a large extent both the zonal mean and asymmetric rainfall changes. This consistency is also found in terms of the year-to-year variability of the zonal mean at both mid- and high latitudes. However, the frontal activity has a complex relationship with rainfall (not every frontal system is associated with rainfall events), and this consistency is unclear over some specific regions. Results presented here highlight the robust link between the change in the asymmetric component of the upper-level circulation, the frontal activity, and rainfall over the mid- to high latitudes of the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

Abstract: Sediments from the continental shelf/coastal region bear significant signals of sea-level, climate change as well as local tectonic information. This study presents a high-resolution magnetostratigraphic and rock magnetic study of a 212.4m core (BH08, with a basal age of 1.06Ma) recovered from the shallow (<30m below sea level) Bohai Sea, China. Astronomical tuning based on the sediment redness (a*) of core BH08 allows the construction of a high-resolution chronology that is assisted by magnetostratigraphic data. Sedimentology and associated proxies (grain size and redness) indicate that the cyclic alternation of neritic/littoral sandy deposits and terrestrial silts/clayey silts was mainly controlled by changes in sea-level and associated base-level at glacial–interglacial timescales. The a* record of the core can be correlated with marine δ18O records at 40- and 100-kyr cycles, indicating that the sediments in the study area are continuous at least at orbital timescales regardless of significant base-level variations. This is likely due to continued subsidence in the basin and creation of accommodation space. The significant lower sedimentary accumulation rates since 750ka might be due to the deviation of the depositional locus from core site because of extreme low sea-level stands during the glacials since the Mid-Pleistocene transition (MPT). Especially the glacial sea-level lowstands might have resulted in bypassing or erosion of sediments on the BH08 core site during peak glacials (MIS 6, MIS 10 and MIS 16), limiting the sediment preservation potential. This study documents the longest Quaternary sedimentary succession in the Bohai Sea and provides, for the first time, a clear link between sedimentation in the area and glacial–interglacial climate-driven sea-level changes. This study also highlights the feasibility of astronomical tuning to obtain high-resolution chronology for shallow shelf deposits, which is otherwise very difficult to be achieved on the basis of magnetostratigraphic data alone. [Copyright &y& Elsevier]

In this study, effects of different sowing times on the yields and qualities of two Isatis species (Isatis tinctoria and Isatis buschiana) were investigated under ecological conditions of Kahramanmaras during 2007-2008 and 2008- 2009 growing seasons. The experiment was designed according to the randomized complete blocks with three replications. The effects of different sowing times on Isatis species under climatic conditions of Kahramanmaras were aimed to determine. According to two-year results, the effects of sowing dates were statiscally significant in almost investigated all of the characters. Autumn sowings were optimum for seed yields in I. tinctoria and I. busctiiana. The highest fruit yields were 393.2 g/m2 in October 2008 and 319.9 g/m2 in March 2009 for I. tinctoria and I. busctiiana, respectively. [ABSTRACT FROM AUTHOR]

Renewed excavations at Horvat 'Eleq support a fresh understanding of this multi-strata settlement. The site was first inhabited in the Iron Age. A fortification system was constructed in the 4th century BCE and was already out of use by the Hellenistic period. The finds indicate that the Hellenistic period saw the zenith of the settlement, in terms of magnitude of construction and extent. New data contradicts Hirschfeld's identification of the site as a single strata, fortified Herodian palace. Reassessment of the date of the fortification at the site and its phases of occupation sheds light on the border between Phoenicia and Judaea during the Persian and Hellenistic periods. [ABSTRACT FROM AUTHOR]

One of the few long instrumental records available for the Arctic is the Svalbard Airport composite series that hitherto began in 1911, with observations made on Spitsbergen, the largest island in the Svalbard Archipelago. This record has now been extended to 1898 with the inclusion of observations made by hunting and scientific expeditions. Temperature has been observed almost continuously in Svalbard since 1898, although at different sites. It has therefore been possible to create one composite series for Svalbard Airport covering the period 1898-2012, and this valuable new record is presented here. The series reveals large temperature variability on Spitsbergen, with the early 20th century warming as one striking feature: an abrupt change from the cold 1910s to the local maxima of the 1930s and 1950s. With the inclusion of the new data it is possible to show that the 1910s were colder than the years at the start of the series. From the 1960s, temperatures have increased, so the present temperature level is significantly higher than at any earlier period in the instrumental history. For the entire period, and for all seasons, there are positive, statistically significant trends. Regarding the annual mean, the total trend is 2.6°C/century, whereas the largest trend is in spring, at 3.9°C/century. In Europe, it is the Svalbard Archipelago that has experienced the greatest temperature increase during the latest three decades. The composite series may be downloaded from the home page of the Norwegian Meteorological Institute and should be used with reference to the present article. [ABSTRACT FROM AUTHOR]

Power spectra of global surface temperature (GST) records (available since 1850) reveal major periodicities at about 9.1, 10–11, 19–22 and 59–62years. Equivalent oscillations are found in numerous multisecular paleoclimatic records. The Coupled Model Intercomparison Project 5 (CMIP5) general circulation models (GCMs), to be used in the IPCC Fifth Assessment Report (AR5, 2013), are analyzed and found not able to reconstruct this variability. In particular, from 2000 to 2013.5 a GST plateau is observed while the GCMs predicted a warming rate of about 2°C/century. In contrast, the hypothesis that the climate is regulated by specific natural oscillations more accurately fits the GST records at multiple time scales. For example, a quasi 60-year natural oscillation simultaneously explains the 1850–1880, 1910–1940 and 1970–2000 warming periods, the 1880–1910 and 1940–1970 cooling periods and the post 2000 GST plateau. This hypothesis implies that about 50% of the ~0.5°C global surface warming observed from 1970 to 2000 was due to natural oscillations of the climate system, not to anthropogenic forcing as modeled by the CMIP3 and CMIP5 GCMs. Consequently, the climate sensitivity to CO 2 doubling should be reduced by half, for example from the 2.0–4.5°C range (as claimed by the IPCC, 2007) to 1.0–2.3°C with a likely median of ~1.5°C instead of ~3.0°C. Also modern paleoclimatic temperature reconstructions showing a larger preindustrial variability than the hockey-stick shaped temperature reconstructions developed in early 2000 imply a weaker anthropogenic effect and a stronger solar contribution to climatic changes. The observed natural oscillations could be driven by astronomical forcings. The ~9.1year oscillation appears to be a combination of long soli–lunar tidal oscillations, while quasi 10–11, 20 and 60year oscillations are typically found among major solar and heliospheric oscillations driven mostly by Jupiter and Saturn movements. Solar models based on heliospheric oscillations also predict quasi secular (e.g. ~115years) and millennial (e.g. ~983years) solar oscillations, which hindcast observed climatic oscillations during the Holocene. Herein I propose a semi-empirical climate model made of six specific astronomical oscillations as constructors of the natural climate variability spanning from the decadal to the millennial scales plus a 50% attenuated radiative warming component deduced from the GCM mean simulation as a measure of the anthropogenic and volcano contributions to climatic changes. The semi-empirical model reconstructs the 1850–2013 GST patterns significantly better than any CMIP5 GCM simulation. Under the same CMIP5 anthropogenic emission scenarios, the model projects a possible 2000–2100 average warming ranging from about 0.3°C to 1.8°C. This range is significantly below the original CMIP5 GCM ensemble mean projections spanning from about 1°C to 4°C. Future research should investigate space-climate coupling mechanisms in order to develop more advanced analytical and semi-empirical climate models. The HadCRUT3 and HadCRUT4, UAH MSU, RSS MSU, GISS and NCDC GST reconstructions and 162 CMIP5 GCM GST simulations from 48 alternative models are analyzed. [ABSTRACT FROM AUTHOR]

Operational rainfall forecasts using the analog method have been issued in Ethiopia since 1987. We evaluate the performance of the forecast system for February-May and June-September rainy seasons over the period 1999-2011. Verification is performed using rainfall data obtained from Ethiopian meteorological stations covering eight homogeneous rainfall regions used in the forecasts. The results reveal that forecasts issued by the National Meteorological Agency (NMA) of Ethiopia, for the past 12 years have a weak positive skill for all eight regions compared with climatology. In terms of ranked probability skill scores, the values are all lower than 10% indicating that the forecast skill is modest. The results further suggest that the forecasting system has bias toward forecasting near-normal conditions and has problems in capturing below average events. In contrast, the forecast has some positive skills in ranking the wet years of February-May season, particularly over the regions where there is high seasonal rainfall variability with significantly positive rank correlations for the above average years. For the main season, however, the forecast is not able to rank wet years or dry years. The extreme low and high rainfall events are mostly missed by the forecast scheme. The results indicate rather low forecast skill for extreme rainfall events in both seasons. Generally, the results indicate that NMA's forecasts have low but positive skill as it is common with results from other forecasting systems for the Greater Horn of Africa region. The underforecasting of dry events is the most serious shortcoming of the system. [ABSTRACT FROM AUTHOR]

Recent advances in satellite retrieval methodology now allow for estimation of particular organic carbon (POC) concentration in ocean surface waters directly from satellite-based optical data. Because of the good coverage, these data reveal small-scale spatial and temporal concentration gradients and document the evolution of surface water POC as well as the underlying driving biogeochemical processes throughout the seasons. Water column nutrient data also reveal biogeochemical activity. However, because of the scarcity of data, the deduction of temporal changes of particle production and export is not possible in most parts of the ocean. Here we present first results from a new study combining both data streams, thereby exploiting the high spatio-temporal resolution of surface POC concentrations from satellite optical sensors with water column nutrient data having sparser coverage but providing information throughout the entire water column. We use a mediumresolution global model with steady-state 3-D circulation that has been optimized by fitting to a large number of hydrographic parameters and tracers, including CFCs and natural radiocarbon. Production and export of POC is allowed to vary monthly, and the magnitudes of the monthly export fluxes are determined by fitting the model to satellite POC data as well as water column nutrient data using the adjoint method. Two cases have been investigated: (1) the production rate of POC is set to be proportional to export production (EP) and the seasonal changes are assumed sinusoidal (meridionally varying amplitude and phase), and (2) the POC production rate is linked to primary production rates (literature). Both cases were run with the same initial state and model settings, and show total cost function decreases of 12 and 95 %, respectively. The POC misfit term alone decreased by 75 and 99.8 %. The integrated annual global POC exports of the two cases are 9.9 and 12.3 Gt Cyr-1, respectively. Overall, the remaining POC and phosphate misfits of both solutions are considered too large, and the difference fields still exhibit significant systematic geographical patterns. This indicates that the present model runs are too simplistic and do not fully explain the data. Further, more refined model setups are needed. [ABSTRACT FROM AUTHOR]

Climate change can exacerbate future regional air pollution events by making conditions more favorable to form high levels of ozone. In this study, we use spectral nudging with the Weather Research and Forecasting (WRF) model to downscale NASA earth system GISS modelE2 results during the years 2006 to 2010 and 2048 to 2052 over the contiguous United States in order to compare the resulting meteorological fields from the air quality perspective during the four seasons of five-year historic and future climatological periods. GISS results are used as initial and boundary conditions by the WRF regional climate model (RCM) to produce hourly meteorological fields. The downscaling technique and choice of physics parameterizations used are evaluated by comparing them with in situ observations. This study investigates changes of similar regional climate conditions down to a 12 km by 12 km resolution, as well as the effect of evolving climate conditions on the air quality at major US cities. The high-resolution simulations produce somewhat different results than the coarse-resolution simulations in some regions. Also, through the analysis of the meteorological variables that most strongly influence air quality, we find consistent changes in regional climate that would enhance ozone levels in four regions of the US during fall (western US, Texas, northeastern, and southeastern US), one region during summer (Texas), and one region where changes potentially would lead to better air quality during spring (Northeast). Changes in regional climate that would enhance ozone levels are increased temperatures and stagnation along with decreased precipitation and ventilation. We also find that daily peak temperatures tend to increase in most major cities in the US, which would increase the risk of health problems associated with heat stress. Future work will address a more comprehensive assessment of emissions and chemistry involved in the formation and removal of air pollutants. [ABSTRACT FROM AUTHOR]

We analyze the short-term transition, on time scales of the order of days and weeks, of the surface fields in the coastal transition zone off Northwest Africa, between 15°N and 25°N, during winter and spring 2005 and 2006. This is a complex region characterized by the baroclinic coastal jet north of Cape Blanc, along-shore convergence and water export at the Cape Blanc giant filament, and substantial mesoscale variability between Capes Verde and Blanc. We use the anomalies of the wind impulse and two different coastal upwelling indexes, evaluated off 17°N, 20°N and 23°N, in order to assess the importance of wind forcing in this short-term variability. We also employ daily and weekly surface maps of wind, temperature, surface height and currents to investigate which are the mechanisms that lead to the relatively fast changes in the flow patterns. The coastal baroclinic jet and the Cape Blanc giant filament are ubiquitous features, the two being intrinsically related through the intensity of upwelling off Cape Blanc. Therefore, the strength of both features responds, to a large extent, to the fluctuations of the northeasterly winds; their intensity is greater in spring than winter but during both seasons they experience relatively fast oscillations related to the intermittency of the wind field. The mesoscalar features are visible in the entire domain, with time scales typically of the order of two weeks, but become prominent in the southern region during spring, apparently related to an intense northward coastal jet south of Cape Blanc. [ABSTRACT FROM AUTHOR]

Changes in growing seasons for 2041-2060 across Africa are projected using a regional climate model at 90-km resolution, and confidence in the predictions is evaluated. The response is highly regional over West Africa, with decreases in growing season days up to 20% in the western Guinean coast and some regions to the east experiencing 5-10% increases. A longer growing season up to 30% in the central and eastern Sahel is predicted, with shorter seasons in parts of the western Sahel. In East Africa, the short rains (boreal fall) growing season is extended as the Indian Ocean warms, but anomalous mid-tropospheric moisture divergence and a northward shift of Sahel rainfall severely curtails the long rains (boreal spring) season. Enhanced rainfall in January and February increases the growing season in the Congo basin by 5-15% in association with enhanced southwesterly moisture transport from the tropical Atlantic. In Angola and the southern Congo basin, 40-80% reductions in austral spring growing season days are associated with reduced precipitation and increased evapotranspiration. Large simulated reductions in growing season over southeastern Africa are judged to be inaccurate because they occur due to a reduction in rainfall in winter which is over-produced in the model. Only small decreases in the actual growing season are simulated when evapotranspiration increases in the warmer climate. The continent-wide changes in growing season are primarily the result of increased evapotranspiration over the warmed land, changes in the intensity and seasonal cycle of the thermal low, and warming of the Indian Ocean. [ABSTRACT FROM AUTHOR]

The trends in wind speed at a typical wind turbine hub height (80 m) are analyzed using the North American Regional Reanalysis (NARR) dataset for 1979-2009. A method, assuming the wind profile in the lower boundary layer as power-law functions of altitude, is developed to invert the power exponent (in the power-law equation) from the NARR data and to compute the following variables at 80 m that are needed for the estimation and interpretation of the trend in wind speed: air density, zonal wind u, meridional wind υ, and wind speed. Statistically significant and positive annual trends are found to be predominant over the contiguous United States, with spring and winter being the two largest contributing seasons. Positive trends in surface wind speed are generally smaller than those at 80 m, with less spatial coverage, reflecting stronger increases in wind speed at altitudes above the 80-m level. Large and positive trends in winds over the southeastern region and high-mountain region are primarily due to the increasing trend in southerly wind, while the trends over the northern states (near the Canadian border) are primarily due to the increasing trend in westerly wind. Trends in the 90th percentile of the annual wind speed, a better indicator for the trend in wind power recourses, are 40%-50% larger than but geographically similar to the trends in the annual mean wind speed. The probable climatic drivers for change in wind speed and direction are discussed, and further studies are needed to evaluate the fidelity of wind speed and direction in the NARR. [ABSTRACT FROM AUTHOR]

By means of a simple mathematical model recently developed by the authors (2010 Phys. Educ. 45 641), the passage of the seasons on the Earth is simulated for arbitrary latitudes, taking into account sunlight attenuation in the atmosphere. The method developed can be used to predict a realistic value of the solar energy input (insolation) that can be absorbed by horizontal ground at sea level on any cloudless day of year. Some ideas for estimating daily insolation on to horizontal ground using the duration of daylight and the length of a shadow at the solar noon are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Total column ozone (TCO) amounts observed by the Dobson spectrophotometer from 1985 to 2008 in Seoul and vertical ozone profiles obtained with the ozonesonde from 1995 to 2007 in Pohang were used to investigate the relationship between the occurrence of Secondary Ozone Peak (SOP) in the Upper Troposphere/Lower Stratosphere (UT/LS) layer and the enhancement in TCO over the Korean Peninsula. Based on Hybrid Single-Particle, Lagrangian Integrated Trajectory (HYSPLIT) simulations, the advection of a northern mid-latitudinal ozone-rich airmass from the northwest is closely related to SOP occurrences, which consequently lead to enhancements in the amount of ozone in both the UT/LS and the total column at stations in Korea. In addition, both the frequency of the northwesterly advection and the northern mid-latitudinal ozone amount are revealed to affect the amount of ozone in the UT/LS and total column by up to 7 DU. The relationship between the SOP occurrence frequency and the long-term TCO trend was investigated with observed data collected in all seasons. The UT/LS ozone enhancements, which are largely affected by SOP occurrences, are considered to be positively related to the TCO trend from 1985 to 2008 over the Korean Peninsula. [Copyright &y& Elsevier]

Abstract: Satellites offer the opportunity to determine the spatial distribution of aerosol properties. In this study the AATSR (Advanced Along Track Scanning Radiometer) Dual View (ADV) algorithm is applied for observing aerosol optical depth (AOD) over Eastern China. A preliminary selection of representative aerosol models was made by a comparison of ADV retrieval for a range of models with AERONET data. The selected fine-, and coarse-mode aerosol models were subsequently used in the ADV retrievals over a wider area where no AERONET data was available. In addition to AOD at wavelengths of 0.555 and 0.659μm, a mixing ratio (the contribution of fine mode aerosol to the total aerosol extinction) was retrieved from the AATSR data for 2008. The results show a seasonal variation of the AODs and mixing ratios over the areas with strong anthropogenic activity; over rural areas the AODs and mixing ratios are low throughout the year. Over urban areas the lowest AODs were observed during the winter, and the highest during the summer. During the winter the fine mode aerosol mixing ratios were higher than during other seasons. [Copyright &y& Elsevier]

Along with chemical research on the Scots pine (Pinus sylvestris L.) growing in the South - Eastern part of Lithuania, the analysis of soil properties was given close attention. The analysed forest soil samples were collected in the spring and summer seasons of 2011. Before sampling, a grid of the area covering 10x 10 km including all biggest forest areas of the territory was made. In total, 42 composite forest soil samples were examined. The conducted analysis measured soil moisture, pH and the content of total organic carbon. The assessment of these parameters and performed statistical analysis has disclosed that the content of total organic carbon positively and significantly correlates with pH and the content of soil moisture. Additionally, it has been determined that the content of total organic carbon tends to increase when pH of soil is close to neutral and a total value of soil moisture does not reach 0,61%. [ABSTRACT FROM AUTHOR]

This paper argues for continuity in purpose and specific results between some hand drawn nebulae, especially those ‘descriptive maps’ by John F. W. Herschel and E. P. Mason in the late 1830s, and the first photographs made of the nebulae in the 1880s. Using H. H. Turners’ explication in 1904 of the three great advantages of astrophotography, the paper concludes that to some extent Herschel’s and Mason’s hand-drawings of the nebulae were meant to achieve the same kinds of results. This is surprising not only because such drawings were conceived and achieved over forty-years earlier, but also because the procedures used in the production of these pictorially and metrically rich images were those directly inspired by cartography, geodesy, and land-surveying. Such drawings provided the standard for what was depicted, expected and aimed at by way of successful representations of the nebulae; standards that seemed to have been used to judge the success of nebular photographs. Being conditions of expectation and possibility for later photography, these drawings were themselves made possible by such techniques of representation and measurement as isolines and triangulation, so fundamental to Imperial and ‘Humboltian science.’ [Copyright &y& Elsevier]

Steady-state infiltration rates (IRs) correlate well with temperature. They have been observed, however, to have values 1.5 to 2.5 times higher than predicted by viscosity, known as the t-effect. Many field studies that have observed the t-effect used continuous IR measurement systems. We measured 67 IRs using double-ring infiltrometers (DRIs) during the 2007 and 2008 autumn seasons in sand and loamy sand soils across a temperature range of 5 to 35°C. We found above-average to good correlation between temperature and IR. For loamy sand (n = 17), IR rate differences were accounted for by viscosity differences, but for sand (a = 30) the IR values were 2.0 to 2.9 times higher than the viscosity-predicted rate. Additionally, we found a difference in the IR temperature regressions based on the time of day of the measurements in the sand. Morning measurements were two times the viscosity-predicted IR, while afternoon measurements were nearly three times. This research corroborates other field studies that observed the t-effect using DRIs. [ABSTRACT FROM AUTHOR]

Abstract: We provide evidence of consistency between the dynamical evolution of main belt asteroids and their color evolution due to space weathering. The dynamical age of an asteroid’s surface (Bottke, W.F., Durda, D.D., Nesvorný, D., Jedicke, R., Morbidelli, A., Vokrouhlický, D., Levison, H. [2005]. Icarus 175 (1), 111–140; Nesvorný, D., Jedicke, R., Whiteley, R.J., Ivezić, Ž. [2005]. Icarus 173, 132–152) is the time since its last catastrophic disruption event which is a function of the object’s diameter. The age of an S-complex asteroid’s surface may also be determined from its color using a space weathering model (e.g. Willman, M., Jedicke, R., Moskovitz, N., Nesvorný, D., Vokrouhlický, D., Mothé-Diniz, T. [2010]. Icarus 208, 758–772; Jedicke, R., Nesvorný, D., Whiteley, R.J., Ivezić, Ž., Jurić, M. [2004]. Nature 429, 275–277; Willman, M., Jedicke, R., Nesvorny, D., Moskovitz, N., Ivezić, Ž., Fevig, R. [2008]. Icarus 195, 663–673. We used a sample of 95 S-complex asteroids from SMASS and obtained their absolute magnitudes and u, g, r, i, z filter magnitudes from SDSS. The absolute magnitudes yield a size–derived age distribution. The u, g, r, i, z filter magnitudes lead to the principal component color which yields a color–derived age distribution by inverting our color–age relationship, an enhanced version of the ‘dual τ’ space weathering model of . We fit the size–age distribution to the enhanced dual τ model and found characteristic weathering and gardening times of τ w =2050±80Myr and respectively. The fit also suggests an initial principal component color of −0.05±0.01 for fresh asteroid surface with a maximum possible change of the probable color due to weathering of ΔPC =1.34±0.04. Our predicted color of fresh asteroid surface matches the color of fresh ordinary chondritic surface of PC 1 =0.17±0.39. [Copyright &y& Elsevier]

Abstract: Galaxias Chaos deviates significantly from other chaotic regions due to the lack of associated outflow channels, lack of big elevation differences between the chaos and the surrounding terrain and due to gradual trough formation. A sequence of troughs in different stages is observed, and examples of closed troughs within blocks suggest that the trough formation is governed by a local stress field rather than a regional stress field. Moreover, geomorphic evidence suggests that Galaxias Chaos is capped by Elysium lavas, which superpose an unstable subsurface layer that causes chaotic tilting of blocks and trough formation. Based on regional mapping we suggest a formation model, where Vastitas Borealis Formation embedded between Elysium lavas is the unstable subsurface material, because gradual volatile loss causes shrinkage and differential substrate movement. This process undermines the lava cap, depressions form and gradually troughs develop producing a jigsaw puzzle of blocks due to trough coalescence. Observations of chaos west of Elysium Rise indicate that this process might have been widespread along the contact between Vastitas Borealis Formation and Elysium lavas. However, the chaotic regions have probably been superposed by Elysium/Utopia flows to the NW of Elysium Rise, and partly submerged with younger lavas to the west. [ABSTRACT FROM AUTHOR]

Background: Patients frequently report that weather changes trigger headache or worsen existing headache symptoms. Recently, the method of empirical mode decomposition (EMD) has been used to delineate temporal relationships in certain diseases, and we applied this technique to identify intrinsic weather components associated with headache incidence data derived from a large-scale epidemiological survey of headache in the Greater Taipei area. Methodology/Principal Findings: The study sample consisted of 52 randomly selected headache patients. The weather time-series parameters were detrended by the EMD method into a set of embedded oscillatory components, i.e. intrinsic mode functions (IMFs). Multiple linear regression models with forward stepwise methods were used to analyze the temporal associations between weather and headaches. We found no associations between the raw time series of weather variables and headache incidence. For decomposed intrinsic weather IMFs, temperature, sunshine duration, humidity, pressure, and maximal wind speed were associated with headache incidence during the cold period, whereas only maximal wind speed was associated during the warm period. In analyses examining all significant weather variables, IMFs derived from temperature and sunshine duration data accounted for up to 33.3% of the variance in headache incidence during the cold period. The association of headache incidence and weather IMFs in the cold period coincided with the cold fronts. Conclusions/Significance: Using EMD analysis, we found a significant association between headache and intrinsic weather components, which was not detected by direct comparisons of raw weather data. Contributing weather parameters may vary in different geographic regions and different seasons. [ABSTRACT FROM AUTHOR]

Many arctic mammals are adapted to live year-round in extreme environments with low winter temperatures and great seasonal variations in key variables (e.g. sunlight, food, temperature, moisture). The interaction between hosts and pathogens in high northern latitudes is not very well understood with respect to intra-annual cycles (seasons). The annual cycles of interacting pathogen and host biology is regulated in part by highly synchronized temperature and photoperiod changes during seasonal transitions (e.g., freezeup and breakup). With a warming climate, only one of these key biological cues will undergo drastic changes, while the other will remain fixed. This uncoupling can theoretically have drastic consequences on host-pathogen interactions. These poorly understood cues together with a changing climate by itself will challenge host populations that are adapted to pathogens under the historic and current climate regime. We will review adaptations of both host and pathogens to the extreme conditions at high latitudes and explore some potential consequences of rapid changes in the Arctic. [ABSTRACT FROM AUTHOR]