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Amphibians are the most threatened vertebrates today, experiencing worldwide declines. In recent years considerable effort was invested in exposing the causes of these declines. Climate change has been identified as such a cause; however, the expectable effects of predicted milder, shorter winters on hibernation success of temperate-zone Amphibians have remained controversial, mainly due to a lack of controlled experimental studies. Here we present a laboratory experiment, testing the effects of simulated climate change on hibernating juvenile common toads (Bufo bufo). We simulated hibernation conditions by exposing toadlets to current (1.5 °C) or elevated (4.5 °C) hibernation temperatures in combination with current (91 days) or shortened (61 days) hibernation length. We found that a shorter winter and milder hibernation temperature increased survival of toads during hibernation. Furthermore, the increase in temperature and shortening of the cold period had a synergistic positive effect on body mass change during hibernation. Consequently, while climate change may pose severe challenges for amphibians of the temperate zone during their activity period, the negative effects may be dampened by shorter and milder winters experienced during hibernation.

Wet atmospheric samples were collected from different locations in the southern region of Jordan during a 5-year period (October 2006 to May 2011). All samples were analyzed for pH, EC, major ions (Ca2+, Mg2+, Na+, K+, HCO3 −, Cl−, NO3 −, and SO4 2−), and trace metals (Fe2+, Al3+,Cu2+, Pb2+, and Zn2+). The highest ion concentrations were observed during the beginning of the rainfall events because large amounts of dust accumulated in the atmosphere during dry periods and were scavenged by rain. The rainwater in the study area is characterized by low salinity and neutral pH. The major ions found in rainwater followed the order of HCO3 > Cl− > SO4 2− and Ca2+ > Na+ > Mg2+ > NH4 + > K+. Trace metals were identified to be of anthropogenic origin resulting from cement and phosphate mining activities located within the investigated area and from heating activities during the cold period of the year (January to April). The wet precipitation chemistry was analyzed using factor component analysis for possible sources of the measured species. Factor analysis (principal component analysis) was used to assess the relationships between the concentrations of the studied ions and their sources. Factor 1 represents the contribution of ions from local anthropogenic activities, factor 2 represents the contribution of ions from natural sources, and factor 3 suggests biomass burning and anthropogenic source. Overall, the results revealed that rainwater chemistry is strongly influenced by local anthropogenic sources rather than natural and marine sources, which is in a good agreement with the results obtained by other studies conducted in similar sites around the world.

We have estimated the rate of changes in the main hydroclimatic characteristics for the period 1961–2008. It has been established that all months are involved in the formation of positive tendencies of mean annual temperatures, with the largest changes corresponding to February (0.62–1.94°C/10 years). It has been found that the changes in annual precipitation amount and annual river runoff are differently directed and mostly statistically insignificant. The cold period of a year is dominated by tendencies for a decrease in the amount of precipitation. A predominance of positive changes in river runoff is observed between October and December.

The vertical structure of surface cyclonic tracks affecting the eastern Mediterranean region is studied on a climatological basis for the cold period of the year. The dataset used is the 1° × 1° ERA-40 Reanalysis for a 40-year period (1962–2001). The vertical tracking of surface cyclonic tracks was performed with the aid of the Melbourne University Vertical Tracking Algorithm. It was found that about 83 % of the cyclones were extended up to the 500-hPa level and almost 65 % up to 200-hPa level, implying that the cyclones are in general well organized. The surface tracks that originate within the examined area exhibit the smallest vertical extension, intensity, radius, and depth compared to the cyclones originating in the other sectors. Moreover, the 500-hPa counterparts for the said cyclones are mainly located to the north-west or south-west of the surface cyclone position, consistent with the baroclinic character of the Mediterranean cyclones. The zonal (eastward) component of motion predominates both at the surface and at 500 hPa.

Astthorsson, O. S., Valdimarsson, H., Gudmundsdottir, A., and Óskarsson, G. J. 2012. Climate-related variations in the occurrence and distribution of mackerel (Scomber scombrus) in Icelandic waters. – ICES Journal of Marine Science, 69: . Based on long-term investigations on sea temperature in Icelandic waters, five climatic periods are defined from the mid-1880s until today. These are a cold period between 1880 and 1920, a warm period between 1921 and 1964, a cold period between 1965 and 1971, one of intermediate conditions (alternating warm and cold) between 1972 and 1995, and finally a warm period from 1996 until today. Mackerel were first reported from Icelandic waters in 1895, were then found intermittently until 1996, and from then appeared almost every year and since 2007 in large numbers in many areas around Iceland. The occurrence of mackerel appears to be confined mainly to warm periods in the North Atlantic Ocean and around Iceland. The unprecedented occurrence and extended distribution of the species began at the onset of the recent warm period during the mid-1990s and, in recent years, 0-group and age 1 mackerel have also been observed in Icelandic waters. This expansion in distribution resulted initially in a bycatch fishery, which then developed into a direct fishery within the Icelandic Exclusive Economic Zone, increasing from ∼1700 t in 2006 to ∼120 000 t in 2009 and 2010.

Palynological data on soil profiles of burozems from Petrov Island offer a means of identifying two periods in their evolution: a cold period that was responsible for the development of podzolized burozems, and a subsequent warm period accompanied by an intensification of accumulative-humic and illuvial-humic soil-formation processes, and this did account for the peculiar morphological structure of contemporary burozems.

Azaarenes concentrations in East of France urban atmospheres through the period between April 2006 and February 2007 are described. Sampling sites were chosen to be representative of three different regions and were situated in Strasbourg (“Alsace region”), in Besancon (“Franche-Comte region”) and in Spicheren (“Lorraine region”). In order to compare the seasonal variability, the sampling campaigns have been performed during the four seasons in Strasbourg, and during two opposed seasons (summer and winter) in Besancon and in Spicheren. Moreover, the sampling campaigns have been performed during 6 h time intervals per day (04:00–10:00; 10:00–16:00; 16:00–22:00 and 22:00–04:00) to assess the diurnal variations of azaarenes concentrations. Mean total azaarenes concentrations were 2.8 ng m −3 in Strasbourg, 1.6 ng m −3 in Besancon and 1.0 ng m −3 in Spicheren. Seasonal variations in the azaarenes concentrations occur with the greatest abundance of all species in the colder months when combustion sources are greatest and when azaarene compounds are mainly associated with the particle phase. A diurnal variation of compound concentrations in the three sites, in warm period, has been observed in accordance with the intensity of the vehicle circulation, with highest concentrations during the morning (04:00–10:00) and the evening (16:00–22:00). In cold period, there is no difference of concentration between these two time intervals of high vehicle circulation in Strasbourg site and in Besancon site. Moreover, in Spicheren site, the highest concentrations were observed during the evening. In this way, it seems that the contribution of domestic heating influenced the diurnal variations of some compounds on the three sites.

Finfish abundance indices, produced from seasonal trawl survey data collected in Long Island Sound, were examined for changes in community composition related to the dynamics of water temperature from 1984 to 2008. In general, seasonal mean catch of species identified a priori as cold adapted significantly decreased while warm-adapted and subtropical species significantly increased over the time series. Bottom water temperature also significantly increased. As a group, annual abundance of cold-adapted species exhibited significant negative correlation with mean bottom water temperatures while warm-adapted species, but not subtropical species, exhibited significant positive correlation. Multivariate analyses identified a shift in community structure producing two primary year-groupings. Spring groupings were clearly delineated as 1984–1998 (cold period) and 1999–2008 (warm period). Autumn groupings were temporally discontinuous in the 1990s with group membership shifting between cold and warm peri...

International audience; The Younger Dryas cooling event disrupted the overall warming trend in the North Atlantic region during the last deglaciation. Climate change during the Younger Dryas was abrupt, and thus provides insights into the sensitivity of the climate system to perturbations. The sudden Younger Dryas cooling has traditionally been attributed to a shutdown of the Atlantic Meridional Overturning Circulation by meltwater discharges1 However, alternative explanations such as strong negative radiative forcing and a shift in atmospheric circulation have also been offered. Here we investigate the importance of these different forcings in coupled climate model experiments constrained by data assimilation. We find that the Younger Dryas climate signal as registered in proxy evidence is best simulated using a combination of processes: a weakened Atlantic Meridional Overturning Circulation, moderate negative radiative forcing and an altered atmospheric circulation. We conclude that none of the individual mechanisms alone provide a plausible explanation for the Younger Dryas cold period. We suggest that the triggers for abrupt climate changes such as the Younger Dryas are more complex than suggested so far, and that studies on the response of the climate system to perturbations should account for this complexity.

This paper investigates whether there is any association between the daily mortality for the wider region of Athens, Greece and the thermal conditions, for the 10-year period 1992–2001. The daily mortality datasets were acquired from the Hellenic Statistical Service and the daily meteorological datasets, concerning daily maximum and minimum air temperature, from the Hellinikon/Athens meteorological station, established at the headquarters of the Greek Meteorological Service. Besides, the daily values of the thermal indices Physiologically Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI) were evaluated in order to interpret the grade of physiological stress. The first step was the application of Pearson’s χ2 test to the compiled contingency tables, resulting in that the probability of independence is zero (p = 0.000); namely, mortality is in close relation to the air temperature and PET/UTCI. Furthermore, the findings extracted by the generalized linear models showed that, statistically significant relationships (p < 0.01) between air temperature, PET, UTCI and mortality exist on the same day. More concretely, on one hand during the cold period (October–March), a 10°C decrease in daily maximum air temperature, minimum air temperature, temperature range, PET and UTCI is related with an increase 13%, 15%, 2%, 7% and 6% of the probability having a death, respectively. On the other hand, during the warm period (April–September), a 10°C increase in daily maximum air temperature, minimum air temperature, temperature range, PET and UTCI is related with an increase 3%, 1%, 10%, 3% and 5% of the probability having a death, respectively. Taking into consideration the time lag effect of the examined parameters on mortality, it was found that significant effects of 3-day lag during the cold period appears against 1-day lag during the warm period. In spite of the general aspect that cold conditions seem to be favourable factors for daily mortality, the air temperature and PET/UTCI exceedances over specific thresholds depending on the distribution reveal that, very hot conditions are risk factors for the daily mortality.

The possibility of enhancing the process performance of the UASB-septic tank for treating strong sewage in Palestine by means of inoculating the reactor with well adapted anaerobic sludge and/or adding a packing media to the upper part of the reactor, creating an anaerobic hybrid (AH)-septic tank, was investigated. To achieve these objectives, two community onsite UASB-septic tank and AH-septic tank were operated in parallel at 2 days HRT for around 8 months overlapping the cold and hot periods of the year in Palestine. The achieved removal efficiencies of CODtot in the UASB-septic tank and AH-septic tank during the first months of operation, coinciding with the cold period and the subsequent hot period, were respectively 50(±15)% and 48(±15)% and 66(±8)% and 55(±8)%. This shows that the UASB-septic tank performed significantly better (p < 0.05) than the AH-septic tank after rather long periods of operation. The difference in the CODtot removal efficiency was mainly due to the better CODss removal efficiencies in the UASB-septic tank. The removal efficiencies over the last 50 days of operation for CODtot, CODsus, CODcol and CODdis were 70, 72, 77 and 55% and 53, 54, 78 and 45% for the UASB-septic tank and AH-septic tank, respectively. Comparing the here achieved COD removal efficiencies with previously reported efficiencies of UASB-septic tanks operated in Palestine shows that the reactor performance in terms of COD removal and conversion, during the first 8 months of operation, has improved substantially by being started with well adapted anaerobic sludge, simulating and predicting long-term performance. Adding packing media did not lead to an improvement.

Using low placement temperature and proper water pipe cooling water, the cracks are rarely appears in the interior of the dam, but the surface of the dam is prone to cracking. During the construction, the surface of the dam may be wet due to several factors such as creep, maintenance and so on, so the effect of the heat preservation is always been over-estimated. For those concrete blocks constructed in cold season, without proper heat preservation, the cracks are easy to appear soon after construction. For those concrete blocks constructed in hot period, under the influence of air temperature, the temperature of those concrete within about 5.0m of the dam surface are hard to control. So the key point to prevent the dam surface constructed in cold period is to take heat preservation measure suiting the on-the-spot situation. And for those dam blocks constructed in hot period, water cure on the surface of the dam can greatly reduce the risk of dam surface cracking.

Green roofs have been investigated as a bioclimatic strategy to improve the energy efficiency of buildings. Quantitative data on this subject are still needed for many specific climatic conditions. This paper deals with the investigation of the green roof thermal performance of an experimental single-family residence in Florianopolis (SC, Brazil), a southern city with a temperate climate. Field measurements during a warm period (01-March-2008–07-March-2008) and during a cold period (25-May-2008–31-May-2008) included internal air temperature of rooms, internal and external surface temperature of three types of roofs (green, ceramic and metallic), heat fluxes through these roofs, green roof's temperature profile, water volumetric content in substrate layer and meteorological data. During the warm period, the green roof reduced heat gain by 92–97% in comparison to ceramic and metallic roofs, respectively, and enhanced the heat loss to 49 and 20%. During the cold period, the green roof reduced heat gain by 70 and 84%, and reduced the heat loss by 44 and 52% in comparison to ceramic and metallic roofs, respectively. From the derived data it has been confirmed that green roof contributes to the thermal benefits and energy efficiency of the building in temperate climate conditions.

Precisely how Upper Palaeolithic human ecology was shaped by changing climate during the Pleniglacial remains a matter of debate, for while this generally cold period is now understood to include complex and often rapid flux in climate, there are still considerable difficulties in resolving climatic variations at particular times and places — derived from various lines of proxy evidence — with the high-resolution proxy record of temperature changes from oxygen isotope analysis of the Greenland ice-cores. In this paper we apply the methodology of large-scale flotation to newly excavated contexts from the Upper Palaeolithic (Gravettian) site of Dolni Vĕstonice II, Czech Republic, to explore the potential of charcoal — as a natural archive of environmental information — to offer information on environmental change towards the end of the middle pleniglacial during Oxygen Isotope Stage 3, between c. 32,500 and 31,200 Cal yr BP. The results of an analysis of ring widths and other anatomical features — interpreted alongside micromorphological data — indicate that this charcoal may capture a higher-resolution record of the changing climatic conditions during which humans were first expanding into these hitherto marginal ecologies and, consequently, shed new light upon the complexity of the lifeways that enabled them to do so.

Hourly mean time series of dust concentration (PM10) measured at 3 m high and a sonic-anemometer measured momentum and kinematic heat fluxes at 8 m high above the surface have been obtained from a 20-m monitoring tower located at Erdene in the Asian dust source region of Mongolia for years of 2009 and 2010. These time series were used to identify dust events and to develop optimal regression equations for the dust concentration of dust events with the friction velocity (u*) and the convective velocity scale (w*). In total, 68 dust events were identified in 2009 (except for November) and 43 dust events for the period from March to August in 2010. The duration of each dust event ranged from 3–29 h in 2009 and 5–35 h in 2010. The maximum hourly mean dust concentration of the dust event was found to be 4,107 μg m− 3 in May in 2009 and 4,708 μg m− 3 in March in 2010 while a minimum of 251 μg m− 3 in August in 2009 and 662 μg m− 3 in June in 2010. The optimal regression equation for the dust concentration (C) of dust events was found to have the form of log C = a + b(u* + cw*)n, where a, b, c and n are constants that vary month to month. The convective velocity scale (w*) that has not been taken into account in most dust modelings was found to enhance the dust concentration of dust events during the cold period from December to March when the soil temperature was below the freezing level for both the stable (w* 0) stratifications, whereas the convective velocity caused a reduction in the dust concentrations during the warm period from April to October, suggesting the importance of the convective velocity to estimate dust concentration of dust events.

We radio-tracked 16 individuals (6 males, 10 females) of the little known Molina’s hog-nosed skunk ( Conepatus chinga (Molina, 1782)) and compared home-range dynamics, movement rates, and densities between a protected area and a landscape fragmented by agriculture. The mean home-range size (95% fixed kernel) was 166.7 ha (SD = 107.5 ha), without significant differences between areas. Home-range size varied significantly between males (mean = 243.7 ha, SD = 76.5 ha) and females (mean = 120.4 ha, SD =77.6 ha). Overlap between home range and core area was extensive between and within sexes in the protected area and more limited in the cropland area. Mean distance traveled between two consecutive resting sites was 269.5 m (SD = 365 m) and did not differ between areas, although movements were greater for males than females. Distance moved was influenced by seasons, being greater during the cold period. Finally, density estimates were consistently greater at the protected area. We argue that home-range size in Molina’s hog-nosed skunks is an inherent species property, whereas population density and territoriality are more flexible parameters that could reflect how the ecosystem state was affected. In our study, the greater dispersion of food patches in the cropland area than in the protected area may be the major factor influencing these parameters.

Using results from coupled climate model simulations of the 8.2 ka climate event that produced a cold period over Greenland in agreement with the reconstructed cooling from ice cores, we investigate the typical pattern of climate anomalies (fingerprint) to provide a framework for the interpretation of global proxy data for the 8.2 ka climate event. For this purpose we developed an analysis method that isolates the forced temperature response and provides information on spatial variations in magnitude, timing and duration that characterise the detectable climate event in proxy archives. Our analysis shows that delays in the temperature response to the freshwater forcing are present, mostly in the order of decades (30 a over central Greenland). The North Atlantic Ocean initially cools in response to the freshwater perturbation, followed in certain parts by a warm response. This delay, occurring more than 200 a after the freshwater pulse, hints at an overshoot in the recovery from the freshwater perturbation. The South Atlantic and the Southern Ocean show a warm response reflecting the bipolar seesaw effect. The duration of the simulated event varies for different areas, and the highest probability of recording the event in proxy archives is in the North Atlantic Ocean area north of 40° N. Our results may facilitate the interpretation of proxy archives recording the 8.2 ka event, as they show that timing and duration cannot be assumed to correspond with the timing and duration of the event as recorded in Greenland ice cores. Copyright © 2011 John Wiley & Sons, Ltd.

The scope of this work was to characterize PM mass and number concentration at typical residential microenvironments in the centre of Athens and to examine the relative contribution of the indoor and outdoor sources. Three residential flats located in densely populated residential areas were studied, during a warm and cold period of 2002. PM10, PM2 and black carbon (BC) mass concentrations, as well as ultrafine and accumulation mode particle number size distributions were recorded indoors and outdoors simultaneously. Outdoor concentrations of all size fractions were significant, and indicative of urban sites affected by heavy traffic. Indoor levels were generally lower than the corresponding outdoor ones. Nevertheless, elevated indoor concentrations were recorded, caused by increased ambient air penetration in the indoor microenvironments and/or indoor particle generation. The mean 24-hr indoor PM10 concentration at all residences was 35.0 ± 10.7 μg/m 3 during the warm period and 31.8 ± 7.8 μg/m 3 during the cold period. The corresponding PM2 concentration was 30.1 ± 11.1 μg/m 3 and 27.2 ± 3.6 μg/m 3 during warm and cold periods, respectively. Regression analysis of indoor and outdoor concentration data revealed that indoor BC may be considered mainly of outdoor origin. A large fraction of the outdoor-generated PM2 and ultrafine and accumulation mode particles also seems to penetrate indoors, causing elevated indoor levels. Regarding indoor particle generation, cooking was the strongest contributor in residential microenvironments.

Glaciers Humans are now the biggest cause of glacier melting. Until recently, that was not true. Glaciers take a long time—decades to centuries—to respond to the environmental changes that control their sizes. They have been retreating gradually from the peak levels they reached in the middle of the 19th century, at the end of a 500-year-long cold period called the Little Ice Age. Marzeion et al. show that that has recently changed though, as climate warming has continued: Over the past 20 or so years, the anthropogenic contribution to glacial mass loss has increased markedly (see the Perspective by Marshall). Science , this issue p. [919][1]; see also p. [872][2] [1]: /lookup/doi/10.1126/science.1254702 [2]: /lookup/doi/10.1126/science.1258584

The nature of cold half-years in midlatitude Asia is investigated using the data from 1917 to 2008. The schemes are developed of transitive forecasts of various characteristics of the thermal cold half-year structure on the basis of the use of seasonal rhythms within the cold half-year: the duration of the whole cold period and pre-spring period and the dates of the end of the coldest winter period. The reasonability of computation scheme adaptation to the certain dynamics of both predictors and predictants is demonstrated. The possibilities are considered of the determination of duration and dates of the coldest winter period coming at certain stations with the lead time of one year according to the conditional repeatability of the process of their temporal variations.

A method for determining the cross-isotherm ocean transport from surface heat flux and ocean temperature data is derived. By computing the volume flux through the isotherm that extend from 191E, 741N to the eastern part of the Kola Peninsula, the flow through the western entrance of the Barents Sea south of 741N is estimated. Using three different surface heat flux datasets, the inflow is found to range from 2.9 to 4.5Sv in winter (October‐March) and from 0.4 to 1.4Sv in summer (April‐ September; 1Sv! 10 6 m 3 s " 1 ). The seasonal variations are stronger than indicated by results from direct current measurements, probably because the seasonal cycle of the surface heat fluxes is overestimated along the considered isotherm. The annual mean inflow ranges from 1.9 to 2.2Sv during a cold period (1986‐1988), and from 2.4 to 3.0Sv during a warm period (1990‐1992), close to reported observations. & 2010 Elsevier Ltd. All rights reserved.

Understanding potential for range expansion is critical when evaluating the risk posed by invasive species. Burmese pythons (Python molurus bivittatus) are established in southern Florida and pose a significant threat to native ecosystems. Recent studies indicate that climate suitable for the species P. molurus exists throughout much of the southern United States. We examined survivorship, thermal biology, and behavior of Burmese pythons from South Florida in a semi-natural enclosure in South Carolina, where winters are appreciably cooler than in Florida, but within the predicted region of suitable climate. All pythons acclimated to the enclosure, but most died after failing to seek appropriate refugia during sub-freezing weather. The remaining snakes used refugia but died during an unusually cold period in January 2010. Although all snakes died during the study, most survived extended periods at temperatures below those typical of southern Florida and none exhibited obvious signs of disease. Our study represents a first step in evaluating the results of climate matching models and we address factors that may affect range expansion in this invasive species.

Antarctic surface snowmelt is sensitive to the polar climate. The ascending and descending passes of the Advanced Microwave Scanning Radiometer for Earth Observing System Sensor (AMSR-E) observed the Antarctic ice sheet in the afternoon (the warmest period) and at midnight (a cold period), enabling us to make full use of the diurnal amplitude variations (DAV) in brightness temperature (Tb) to detect snowmelt. The DAV in vertically polarized 36.5 GHz Tb (DAV36V) is extremely sensitive to liquid water and can reduce the effects of the structural changes in snowpacks during melt seasons. A set of controlled experiments based on the microwave emission model of layered snow (MEMLS) were conducted to study the changes of the vertically polarized 36.5 GHz Tb (Δ36V) during the transitions from dry to wet snow regimes. Results of the experiments suggest that 9 K can be used as a DAV36V threshold to recognize snowmelt. The analyses of snowmelt suggest that the Antarctic ice sheet began to melt in November and became almost completely frozen in late March of the following year. The total cumulative melt area from 2002 to 2011 was 2.44 × 106 km2, i.e., 17.58% of the Antarctic ice sheet. The annual cumulative melt area showed considerable fluctuations, with a significant (above 90% confidence level) drop of 5.24 × 104 km2/year in the short term. Persistent snowmelt (i.e., melt that continues for at least three days) detected by AMSR-E and hourly air temperatures (Tair) were very consistent. Though melt seasons became longer in the western Antarctic Peninsula and the Shackleton Ice Shelf, Antarctica was subjected to considerable decreases in duration and melting days in stable melt areas, i.e., −0.64 and −0.81 days/year, respectively. Surface snowmelt in Antarctica decreased temporally and spatially from 2002 to 2011.

The baroclinic depression that affected the area of Cyprus during the cold period, between 28 and 29 January 2008 was thoroughly studied and is presented in the present paper. A small perturbation on a northwesterly flow to the north of Cyprus has initiated the generation of the depression and in 24 h this developed into a deep baroclinic system. This depression was associated with intense weather phenomena, such as heavy thunderstorms with hail and near gale force winds. Strong cold advection resulted in a significant temperature decrease; precipitation even in lower altitudes was in the form of snow, while the accumulated rainfall corresponded to the 25% of the monthly normal. January 2008 is considered as a dry month, despite the fact that, on the average, January is considered as the wettest month of the year. In this study, the evolution and development of the depression was investigated from synoptic, dynamic, energetic and thermodynamic perspectives, in order to enhance our knowledge on the life cycle and behaviour of similar depressions over the area with extreme characteristics.

A mammalian fauna composed of 40 species associated with Xiaogushan Man was unearthed during the archaeological excavations from 1981 to 2007 at Xiaogushan Paleolithic Site, Haicheng, Liaoning Province. The analyses of the fauna and comparison with other related faunas indicate that Xiaogushan fauna is very similar to that of Shanchengzi, Gulongshan and Yushu. It is a typical fauna of Northern Region. Its age is within the middle to late stages of the Late Pleistocene (80–20 ka). Influenced by cold period MIS4, the cold forms appeared in the fauna. Nevertheless the decrease in temperature was not very much and the climate was still a temperate one. The fauna’s environment was generally humid, with large forest, some water areas and grasslands. It is suitable for prehistoric human habitation during temperate seasons with considerable food and water resources. The cold period MIS4 might push prehistoric human southward to temperate areas or stimulate them to develop fire using and making techniques.

A recent record cold spell in southern Florida (2–11 January 2010) provided an opportunity to evaluate responses of an established population of Burmese pythons (Python molurus bivittatus) to a prolonged period of unusually cold weather. We observed behavior, characterized thermal biology, determined fate of radio-telemetered (n = 10) and non-telemetered (n = 104) Burmese pythons, and analyzed habitat and environmental conditions experienced by pythons during and after a historic cold spell. Telemetered pythons had been implanted with radio-transmitters and temperature-recording data loggers prior to the cold snap. Only one of 10 telemetered pythons survived the cold snap, whereas 59 of 99 (60%) non-telemetered pythons for which we determined fate survived. Body temperatures of eight dead telemetered pythons fluctuated regularly prior to 9 January 2010, then declined substantially during the cold period (9–11 January) and exhibited no further evidence of active thermoregulation indicating they were likely dead. Unusually cold temperatures in January 2010 were clearly associated with mortality of Burmese pythons in the Everglades. Some radio-telemetered pythons appeared to exhibit maladaptive behavior during the cold spell, including attempting to bask instead of retreating to sheltered refugia. We discuss implications of our findings for persistence and spread of introduced Burmese pythons in the United States and for maximizing their rate of removal.

Zusammenfassung 1. Die in vier verschiedenen Stallen mit dem Verdunstungsmesser nach Piche (Piche-Rohr) zu verschiedenen Jahreszeiten gemessenen Verdunstungsmengen lagen zwischen 5,3 und 31,2 ml in 7 Tagen. 2. Die Grose der mit dem Piche-Rohr gemessenen Verdunstungsmenge hangt auch im Stall von der Temperatur und der relativen Feuchte der Stallluft, von der Luftgeschwindigkeit und von der Beobachtungsdauer ab. 3. Ausschlaggebend fur die Verdunstungsmenge sind im Stall Temperatur und relative Feuchte der Stalluft. Beide Grosen ergeben das Sattigungsdefizit der Stalluft. In der Rangkorrelation ergab sich zwischen Sattigungsdefizit und Verdunstungsmenge ein Korrelationskoeffizient “e” zwischen 0,938 und 0,964. 4. Der Einflus der Luftgeschwindigkeit tritt in Stallen mit ublicher Warmedammung gegenuber dem Sattigungsdefizit besonders bei hoheren Verdunstungswerten zuruck. 5. Sattigungsdefizit und Verdunstungsmenge sind unter stallublichen Bedingungen linear miteinander verknupft. 6. Das Piche-Rohr ermoglicht gegenuber den bisher ublichen Messungen eine Aussage uber das durchschnittliche Stallklima. Es wird daher vorgeschlagen, das Piche-Rohr fur die Beurteilung des Stallklimas mit zu benutzen. Der Wert solcher Messungen ist um so groser, je mehr andere Stallklimafaktoren gleichzeitig ermittelt werden. Dabei steht die Stallufttemperatur im Vordergrund. 7. Fur die kalte Jahreszeit werden in Anlehnung an DIN 18910 Mindestverdunstungsmengen abgeleitet: Pferde- und Rinderstall 6,0, Zuchtschweinestall 9,0, Mastschweinestall 7,0, Huhnerstall 5,0 ml in 7 Tagen. Fur die warme Jahreszeit werden als obere Grenze der Zutraglichkeit 25,0 ml in 7 Tagen angesetzt. Optimale Stallklimasituationen ergeben im Pferde- und Rinderstall eine Verdunstungsmenge zwischen 7,5 und 20 ml, im Mast- und Zuchtschweinestall zwischen 9 und 22 ml und im Huhnerstall zwischen 8 und 21 ml in 7 Tagen. 8. Anschaffungs- und Wartungsaufwand des Piche-Rohres sind gering. Eine Ausfuhrung in unzerbrechlichem Material ware fur den Einsatz im Stall zu begrusen. Summary Water evaporation measurement to determine atmosphere in animal buildings Measurements in four different animal buildings (two for cows, one for pigs and one for poultry) carried out with a Piche hygrometer at various times of the year gave values between 5.3 and 31.2 ml. over seven days. Under the usual conditions evaporation depends in a linear fashion on the deficit of mean saturation of the air of the building during the period of observation. The saturation deficiency is obtained by calculating the temperature and the relative humidity of the ambient air. The rate of air flow in the stall is equally influenced by the evaporation value. The measure of this evaporation thus allows one to determine the mean for the atmosphere of a stall over a period of one more days. With the help of DIN 18910 the minimal evaporation volumes are deduced for the cold period of the year as follows: over a period of seven days for cow stalls 6.0 ml., pig rearing stalls 9.0 ml., pig fattening stalls 7.0 ml., poultry house 5.0 ml. The authors also indicate the evaporation volumes which condition the upper limit compatible with health in stalls and also the optimal atmospheric conditions for different species of livestock. It is suggested that the Piche tube is in all respects a suitable instrument for measuring the atmosphere in animal houses. Resume Determination de l'atmosphere d'une etable par mesure de l'evaporation de l'eau On mesure au moyen d'un hygrometre selon Piche, dans 4 etables differentes et a des periodes de l'annee differentes, des volumes d'evaporation variant de 5,3 a 31,2 ml en 7 jours. Dans les conditions habituelles, l'evaporation depend de facon lineaire du deficit de saturation moyen de l'air de l'etable, pendant la duree de l'observation. Le deficit de saturation s'obtient par calcul a partir de la temperature et de l'humidite relative de l'air ambiant. La vitesse de l'air dans l'etable est egalement influencee par la valeur de l'evaporation. La mesure de cette evaporation permet donc d'etablir une moyenne de l'atmosphere d'une etable, pour la duree d'un ou de plusieurs jours. Comme appui a DIN 18910, des volumes d'evaporation minima sont deduits pour la periode froide de l'annee: en 7 jours, ecuries et etables a vaches 6,0 ml, etables pour porcs d'elevage 9,0 ml, etables pour porcs a l'engraissement 7,0 ml, poulaillers 5,0 ml. On indique en outre les volumes d'evaporation conditionnant la limite superieure de salubrite d'une etable et une atmosphere optimum pour les differentes especes d'animaux. On propose l'emploi du tube de Piche pour l'analyse de l'atmosphere d'une etable. Resumen Medicion de la evaporacion acuatica para enjuiciar el clima de un establo Con el evaporometro segun Piche se midieron en cuatro establos diferentes en diversas estaciones del ano unas cantidades de evaporacion comprendidas entre 5,3 y 31,2 ml en un plazo de 7 dias. Las cantidades evaporadas dependen en los establos, bajo condiciones usuales, del deficit medio de saturacion del aire estabular durante el espacio de tiempo que dura la observacion. El deficit de saturacion se calcula a partir de la temperatura y de la humedad relativa del aire en cuestion. Tambien la velocidad del aire estabular ejerce influjo sobre la cantidad evaporada. Por tanto, la medicion de la evaporacion permite enjuiciar el clima estabular medio por el espacio de uno o varios dias. Guiandose por DIN 18.910, se derivan cantidades minimas de evaporacion para la estacion fria del ano: establo para caballos y vacas 6,0 ml, establo para cerdas de cria 9,0 ml, porquerizas para cerdos de engorde 7,0 ml y gallineros 5,0 ml en 7 dias. Ademas se indican las cantidades de evaporacion para el limite superior de la conveniencia de un clima estabular y para los ambitos optimos del clima en los establos para las diversas especies animales. Recomiendase tambien utilizar el tubo de Piche para enjuiciar un clima estabular.

To estimate the anthropogenic effect of the city of Tomsk on the measurements of the aerosol optical thickness (AOT) and the columnar water vapor of the atmosphere in the eastern suburb of Tomsk (Akademgorodok), two issues are discussed: (1) the comparative analysis of the data of simultaneous measurements in the suburban zone and at the background region (∼60-km distance), and (2) the dependence of the aerosol turbidity in the suburb on the air mass transfer direction. In addition to the spectral atmospheric AOT, we also considered two AOT components: fine and coarse aerosol. It is noted that variations of the atmospheric turbidity characteristics are mainly caused by synoptic-scale processes and manifest themselves similarly in urban and background regions. During the summertime, the AOT and columnar water vapor of the atmosphere in the two abovementioned regions are statistically indistinguishable, indicating the absence of the anthropogenic urban effect. During the cold period, the suburban zone may be characterized by higher atmospheric turbidity, seemingly due to the inversion accumulation of aerosol. The dependence of the AOT on the wind direction has the following features: (1) overall, the largest aerosol turbidity is observed during winds blowing from the southern sector; (2) during the cold period, the fine AOT component is, on average, 14% higher in cases of air mass transfer from the direction of the city (from the west and northwest directions); and (3) the coarse AOT component is slightly higher during westward air transfer than during an eastward one.

Since the end of the 19th century, global air temperature has been increasing. The period after 1976 is called the period of the most intensive warming. In Russia, the average annual air temperature rises at a rate of + 0.43 ° C / 10 years. The change of precipitation over the last 50-60 years on average in Russia is not significant. In the Baikal region, precipitation increase during the warm period (10-11%) and decrease during the cold period (4%). It is reflected on hydrological regime and the factors of river flow formation. The regional features of the hydrological regime dynamics of the Baikal region against the background of climate change are considered. Groups of the rivers with similar alternations of low water and high-water periods are allocated. Trends in runoff are analyzed. The increase in air temperature leads to intra annual redistribution of river flow. The majority of statistically significant trends of river run off are observed during the cold period of year.

The earthen built heritage presents today a state of deterioration due to the climate changes that put it seriously at risk, through the degradation of its envelope building materials. These degradations lead its occupants to rehabilitate it by using modern building materials. This paper focuses on the rehabilitation of vernacular earthen architecture and its influence on the thermal behaviour of ksourian houses in sub-arid zones. It is based on a comparative study that combines the site measurements and the numerical simulation by Energyplus. Two courtyard houses, constructed of an adobe brick, were evaluated, one in its initial shape and the other rehabilitated. The results shows that the rehabilitation of the envelope made on this house did not influence its thermal qualities significantly; a very small difference justified on its internal thermal behaviour was recorded in cold period and almost minor during summer.

Atmospheric sampling (gas and particle-phases) of phenols and nitrophenols (PNP) were performed between 2002 and 2004 in Strasbourg (east of France) and its vicinity. Sites were chosen to be representative of urban (Strasbourg), suburban (Schiltigheim) and rural (Erstein) conditions. Field campaigns were undertaken simultaneously in urban and suburban and urban and rural sites during three seasons on glass fibre filters and XAD-2 resin by using high volume samplers. Concentrations of compounds were determined by analysis with gas chromatography- mass spectrometry (GC-MS) after a sylilation step using N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide (MtBSTFA) reagent. Mean total concentrations varied between 21.1 ng m-3 for the rural site, 23.5 ng m-3 for the suburban site, and 25.2 ng m-3 for the urban site. At the three sites, the most abundant compounds of those measured were phenol, followed by 4-methyl-2-nitrophenol for the rural site and by 2,4-dinitrophenol for the urban and suburban sites. In terms of concentrations, there was negligible difference between the three sites, independently of the seasons considered. On the other hand, a difference in concentrations has been observed between the three sites according to the periods of sampling, especially during the spring. The observed diurnal variations of compounds in warm period (spring) were essentially dependent of the vehicle circulation. In cold period (fall and winter), it seemed that the contribution of domestic heating influence the diurnal variations of some compounds in rural site while for the two other sites (urban and suburban), the intensity of the vehicle circulation seemed predominant.

We report the data on changes in snow cover characteristics obtained at meteorological stations Tulun and Bokhan and in their neighborhoods for the period 1961–1990. We examine the changes in snow cover, air temperature and soil temperature at depths of 20, 40 and 80 cm.

Temporal and spatial changes in abundance, prosome length, oil sac volume, molting patterns and morphometric parameters were studied in Calanus euxinus from the Black and Marmara Seas. In the south‐western part of the Black Sea and deep shelf zone near Sinop the abundance of C. euxinus was high during the whole studied period (2000–2005), with a maximum 23,400 ind m−2 in March 2004. In the Marmara Sea near the Prince Islands in the deep zone the mean annual abundance of C. euxinus was 47 times lower than in the deep zone of the Black Sea (during 2000–2007). However, this parameter reached a significant magnitude of 12,264 ind m−2 in spring in Izmit Bay. During the warm season, C. euxinus are rare in the Marmara Sea. The high temperature and salinity accelerate development in this species; therefore, preadults and adults possess reduced prosome length and oil sac volume. In the cold period in the Marmara Sea the size and lipid content in late copepodite stages increase, especially in Izmit Bay. Similar siz...

This paper presents a comparison of the characteristics of the electricity demand for London, UK and Athens, Greece and explores its relationship with both climate and non-climate related factors. Year-to-year trends for both cities are identified, associated mainly with economic, social and demographic factors. In addition, several other effects such as weekly and holiday effects, unrelated to weather conditions are detected and are examined in comparison for the two cities. Gross National Product (GNP) per capita has been employed to aid de-trend the data in order to isolate the weather/climate influence on electricity demand. Temperature has been found to play the most important role in controlling the electricity load demand, especially for Athens. For both cities electricity demand peaks in winter but for Athens a second significant peak is apparent in the summer, not present in London. Thermal comfort levels for both cities have also been identified and compared. The optimum ambient temperature for low levels of electricity demand is found to be 20 °C for Athens and 16 °C for London. Using the approach of cooling and heating degree-days, it was identified that the sensitivity of the system electricity-demand/air-temperature is greater during the cold period of the year for both cities.

The aim of this study is to evaluate the possible associations between daily hospital admissions for cardiovascular, respiratory and digestive diseases in Salamanca (Spain) and weather conditions during the winters of 1995–2005. An objective daily air mass classification was performed by means of statistical analysis of ground-level meteorological data. This afforded seven main circulation weather types (CWTs) for the cold period, and the frequency distributions of these types and their meteorological characteristics were analysed. A summary of the main characteristics of the hospital admission series and their distribution over the 10 years studied, together with the frequency distributions of the different diseases classified by ages, the average number of the hospital admissions for each day of week, type of disease and sex, is given. In addition, a comparison between air mass classification and hospital admissions was made using an admission index (AI), for each disease. Significant increases in hospital admissions for the cardiovascular AI were evident 24–48 h after a day characterized by an anticyclonic air mass, 4–5 days after a day characterized by a westerly air mass and 6–7 days after an easterly flow. For the respiratory AI, an increase was observed 2–3 days after a cyclonic situation, 4 days after a northeasterly situation, while for days characterized by southwesterly air masses no delay was observed. These results indicate that the effects of weather conditions on hospital admissions tend to occur some days after exposure. Copyright © 2008 Royal Meteorological Society

The concentrations of PAHs in fine particles were determined at two sites, which were Jongno, one of the urban core sites of Seoul, and Yongin, a downwind site of Seoul. The average concentration of PAHs in was with the range of at Jongno site of Seoul from August 2006 to August 2007, and with the range of at Yongin site from September to November of 2006. In the results of monthly comparison, the concentration of PAHs in August was the lowest level of , but the highest level of in January. The seasonal comparison showed the concentration in winter was higher by the factor of 11.9 than in summer. The concentrations of PAHs during a warm period (NovemberMarch) increased as 5.1 times higher than those during a cold period (AprilOctober). The concentrations of PAHs were assumed to be largely attributed to the consumption of fossil fuels, temperature, mixing height, and photochemical reactions in Seoul metropolitan area.

A multi-millennial simulation with the CSIRO Mark 2 coupled global climatic model has been used to determine whether climatic conditions approximate to those experienced by the medieval Norse settlers in Greenland could be identified. The aim of this analysis was to see whether such conditions could be replicated by the natural climatic variability in this unforced simulation, in order to counteract claims that the current observed global warming is merely another example of this type of climatic regime. This view has been expressed in the media in an attempt to refute the existence of a CO2-induced global warming. A 291-year period of above-average temperature followed by a 41-year cooler period were identified in one millennium of the simulation, and subsequently used as an analogue of conditions representative of the time of the Norse settlements. Considerable interannual variability existed in both these periods, but with noticeable positive and negative surface temperature anomalies in the warm and cold periods respectively. Thus the warm period was not a time of uniform benign conditions. Above-average precipitation was also associated with the warm period, and these climatic conditions would have enhanced pasture growth and hay production (the only crop the Norse produced) thereby sustaining the livelihood of the Norse Greenlanders. The climatic conditions associated with the cold period in the model were probably sufficient to limit the survival prospects of the settlers, especially when other, probably more critical, deleterious factors are taken into account. The temperature anomalies replicated in the simulation are similar to the limited proxy data, but may be smaller in magnitude: nevertheless they appear to be sufficiently large to have affected the viability of the Norse Greenlanders. After considering possible climatic mechanisms that could have contributed to these warm and cold periods it was concluded that they are simply a consequence of stochastic influences generated by nonlinear processes in the simulation. Thus this simulation provides no support for the contention that the current global warming is a manifestation of conditions prevailing during the Norse settlements in Greenland.

The behavior of water-soluble organic compounds arriving in forest litter significantly varies between the warm and cold seasons. Their rapid mineralization occurs in the summer: the removal of introduced compounds from the forest litter and their inclusion into humus substances are almost absent. At the input of water-soluble organic compounds to forest litter during the cold period, the mineralization processes decrease; they recommence only in the next warm period. However, the initial compounds have undergone some transformations by this time, which significantly increases their microbiological stability and decreases their migration capacity. The labeled compounds introduced in the fall are fixed within the forest litter and predominantly enter into the microbial and fungal biomass. Transformed labeled compounds enter into the humus-accumulative A1 horizon due to migration followed by their inclusion into the mineral-humus component of this horizon. Assessing the role of migration in the development of the humus-accumulative horizon in podzolic soils shows the secondary role of migration processes. The major role is played by the formation of the humus-accumulative horizon in accordance with the classical concepts of the soddy process.

Summary Phytophthora root rot on Abies fraseri trees was monitored from 2001 to 2007 within the disease front of a 12-year-old Virginia plantation where trees had been dying of the disease since 1994. After a slow increase in early foliage symptom development from July 2001 to September 2002, the frequency of A. fraseri trees with early symptoms accelerated for about 15 months. While the slow increase occurred during a 18.7% lower than normal rainfall period and the acceleration occurred during a 31.2% higher than normal rainfall period, the percentage of trees with early symptoms continued to increase during the mid-winter months (December–February) when the estimated mean minimum daily soil temperature (25 cm depth) was unfavourable (

In 573 individuals of common voles (Microtus arvalis) trapped in northeastern Lithuania from October to April in 2004–2009, growth depression for the juveniles of this species was observed in January–February, while for subadults in January–March. Growth depression was strongest in subadult voles. In harsh winters, subadults were smaller than in mild winters, whereas juveniles were larger. Growth depression was more pronounced and of longer duration in skull characters than in body mass. Cranial growth in M. arvalis was more inhibited than in Myodes glareolus. In winter and early spring, the juveniles of M. arvalis had the average body mass of 14.5 ± 0.07 g and the average body length of 81.6 ± 0.24 mm, whereas subadults 18.1 ± 0.27 g and 89.2 ± 0.70 mm, respectively. Body mass in juveniles from October to April grew by 1.0 g, whereas in subadults decreased by 2.0 g. Our main finding is that despite global climate warming tendencies growth depression in small mammals still occurs during the cold period.

An attempt was made to reconstruct winter climate conditions in Japan for the period 1810/1811 to 1858/1859 on the basis of daily weather records documented in old diaries. Daily weather maps for each winter were drawn using 19th century weather records collected by our research group. Maps were divided into five types by classifying daily snowfall and rainfall distributions and the occurrence frequencies of each weather pattern for the period 1810/1811 to 1858/1859 were analysed. It was found that the occurrence frequencies of winter monsoon weather patterns were high from the late 1820s to the early 1840s. This period almost coincided with a summer cold period in the 19th century. The result implies that strengthening of a cold air mass around Japan occurred in the late 1820s, not only in summer but also in winter. The frequencies of the typical winter monsoon patterns correspond with the freezing dates of Lake Suwa, which have been used as an indicator of winter coldness in previous studies. On the basis of the frequencies of the winter monsoon weather patterns, mean January temperatures for western Japan were estimated. In the time series of estimated temperatures, a cooling period from the late 1820s to the early 1830s was revealed. Copyright © 2007 Royal Meteorological Society

The variability of sea surface temperature (SST) in the Japan Sea is investigated using the complex EOF analysis of daily data produced at Tohoku University, Japan (New Generation SST; 2002–2006). The relationship with the wind field is investigated from the daily NCEP/NCAR reanalysis data with a 1° spatial resolution. Anomalies in the SST (SSTAs) are calculated by subtracting the basin-average annual variation estimated as a leading mode of temperature. The leading mode of an SSTA represents a adjustment to the annual mean variation, most significant in December in the zone of subtropical waters entering the sea through the Korean Strait and in the northwestern sea, over which a cyclonic wind curl develops in the cold period. The semiannual variability mode is identified, which is characterized by the largest temperature increase (decrease) in the western branch of the subarctic front (in the Tatar Strait), which lags by two months behind the semiannual changes in wind curl over the sea. An episodic SSTA movement is detected in the northern part of the sea, which moves from east to west along the western branch of the Tsushima Warm Current with a speed corresponding in magnitude to an advective scale.

Castanea and Aesculus trees were protected for consumption of nuts as food during the Jomon Period. Climatic factors affected the selection of kinds of consumed nuts. Castanea was mainly consumed during warm periods and Aesculus was consumed during cold periods. However, this could have been a regional phenomenon in northern Japan. It is possible that in southern warmer areas Castanea either might be protected constantly, or the protection of these plants was not necessary because forest productivity in the southern area is greater than that of the northern area. To understand the influence of temperature on Castanea hansaibai, pollen analysis was conducted at the Satohama site. In addition, the distribution of the intermediate stage between wild and domestication (hansaibai) during the Jomon Period was studied based on pollen analyses. At the Satohama site, protection of Castanea started during the warm period in the Early Jomon Period (7000–4500 years BP) and continued to be observed during the next cold period. The Tohoku region (the northern part of Honshu Island) and the Hokuriku region (Japan Sea Coast area in Central Japan) was the main distribution area. In this study, no evidence of the protection of either species in Western Japan was detected. Climate and the necessity for large amounts of food preservation for winter might influence this activity.

Twenty-five fossil insect assemblages are described from discrete lenses of or-ganic material in a gravel sequence at Four Ashes. The youngest date of 30,500 years B.P. obtained on the organic materialhas confirmed that the till overlying the gravels is Late Devensian (Weichselian) in age. The analyses of the insect faunas have shown conclusively for the first time the existence of climatic changes in one geographic area during the Early and Middle Devensian in Britain. Some of the earliest insect faunas can be correlated with the Brorup Interstadial, when boreal forests existed in the English Midlands. It is suggested that a cold period prior to 43,000 years ago (but post-Brorup) may have caused the elimination of the trees, because around 40,000 years ago the insects indicate that there was a rapid climatic amelioration when it was warm enough for trees to grow again in that area. Around 36,000 years ago there was another climatic deterioration when the thermophilous insect species were replaced by a large number of arctic stenotherms and a tundra type of environment. This cold period lasted for at least 6,000 years and probably became increasingly severe with the approach of the main Devensian ice advance sometime after 30,500 years B.P.

Tidal deposits dating from the penultimate interglacial (Oxygen Isotope Stage 7) are preserved on a bank of the River Seine at Tancarville. The foraminiferal assemblages indicate a gradual cooling towards Arctic conditions, which corresponds to the onset of the penultimate cold period. This cooling started before or during the drop in sea level in Europe, in contrast to the situation at the end of the last interglacial (Eemian) when Europe remained warm even during the period of falling sea level.

In the present study, we tested the applicability of the extended force-restore model (eFRM) to estimating soil-frost depth in the Tokachi district where the soil is a type of volcanic ash. The optimal thermal conductivity of the snow (TC-S) in each cold period varied from 0.074 to 0.172 W m-1 K-1, with root-mean-square errors (RMSEs) ranging from 0.020 to 0.039 m. The difference between observed and estimated maximum soil frost depth (SFDmax) was less than 0.03 m. The fixed TC-S through the six cold periods from 2001 to 2007 was optimized as the value of 0.173 W m-1 K-1 with minimum RMSE of 0.043 m. When this optimal value of TC-S was used to estimate SFDmax, the difference between the observed and estimated values was 0.04 m at most, with the exception of 2003-2004 and 2004-2005, when little soil-frost developed. Our results showed that even though we considered the TC-S to be invariant over time, the eFRM was able to estimate soil-frost depth with an accuracy of a few centimeters using only mean daily air temperature and snow depth as inputs.

An attempt is made to identify and investigate the structure, behaviour and synoptic characteristics of cyclogenesis over the Aegean Sea. A simple, realistic and easily used methodology of identification, in an analytical form, was established. This combines two types of criteria: synoptic and dynamic/thermodynamic. Six synoptic categories that could favour cyclogenesis over the Aegean Sea are distinguished according to the synoptic criteria. Grid-point values of geopotential height and temperature are used to calculate the dynamic/thermodynamic criteria, which are used to identify potential cases of cyclogenesis with respect to the thermodynamic prerequisites and the time continuance. It is demonstrated that cyclogenesis over the Aegean Sea is not as rare as was believed. The majority of cases result from the prevalence of a south-westerly pow, a long-wave trough and a closed system over the Aegean Sea. The cyclogenesis appears to occur primarily in the cold period of the year, mainly from October to May, and to have a small intensity and lifetime. I. Introduction