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Aim High‐altitude pulmonary oedema (HAPE) is a non‐cardiogenic pulmonary oedema that can occur during rapid ascent to a high‐altitude environment. Classically, HAPE has been described as a condition resulting from a combination of pulmonary vasoconstriction and hypertension. Inflammation has been described as important in HAPE, although as a side effect of pulmonary oedema rather than as a causative factor. In this study, we aim to understand the role of hypoxic response in myeloid cells and its involvement in pathogenesis of HAPE. Methods We have generated a conditional deletion in mice of the von Hippel‐Lindau factor (VHL) in myeloid cells to determine the effect of a deregulated hypoxic response in pulmonary oedema. Results The deletion of VHL in pulmonary myeloid cells gave rise to pulmonary oedema, increased pulmonary vascular permeability and reduced performance during exertion. These changes were accompanied by reduced stroke volume in the left ventricle. Conclusion In this model, we show that a deregulated myeloid cell hypoxic response can trigger some of the most important symptoms of HAPE, and thus mice with a deletion of VHL in the myeloid lineage can function as a model of HAPE.

KEY POINTS: We sought to determine the isolated and combined influence of hypovolaemia and hypoxic pulmonary vasoconstriction on the decrease in left ventricular (LV) function and maximal exercise capacity observed under hypobaric hypoxia. We performed echocardiography and maximal exercise tests at sea level (344 m), and following 5–10 days at the Barcroft Laboratory (3800 m; White Mountain, California) with and without (i) plasma volume expansion to sea level values and (ii) administration of the pulmonary vasodilatator sildenafil in a double‐blinded and placebo‐controlled trial. The high altitude‐induced reduction in LV filling and ejection was abolished by plasma volume expansion but to a lesser extent by sildenafil administration; however, neither intervention had a positive effect on maximal exercise capacity. Both hypovolaemia and hypoxic pulmonary vasoconstriction play a role in the reduction of LV filling at 3800 m, but the increase in LV filling does not influence exercise capacity at this moderate altitude. ABSTRACT: We aimed to determine the isolated and combined contribution of hypovolaemia and hypoxic pulmonary vasoconstriction in limiting left ventricular (LV) function and exercise capacity under chronic hypoxaemia at high altitude. In a double‐blinded, randomised and placebo‐controlled design, 12 healthy participants underwent echocardiography at rest and during submaximal exercise before completing a maximal test to exhaustion at sea level (SL; 344 m) and after 5–10 days at 3800 m. Plasma volume was normalised to SL values, and hypoxic pulmonary vasoconstriction was reversed by administration of sildenafil (50 mg) to create four unique experimental conditions that were compared with SL values: high altitude (HA), Plasma Volume Expansion (HA‐PVX), Sildenafil (HA‐SIL) and Plasma Volume Expansion with Sildenafil (HA‐PVX‐SIL). High altitude exposure reduced plasma volume by 11% (P

Key points Acclimatization to hypoxia leads to a reduction in plasma volume (PV) that restores arterial O2 content.Findings from studies investigating the mechanisms underlying this PV contraction have been controversial, possibly as experimental conditions were inadequately controlled.We examined the mechanisms underlying the PV contraction evoked by 4 days of exposure to hypobaric hypoxia (HH) in 11 healthy lowlanders, while strictly controlling water intake, diet, temperature and physical activity.Exposure to HH‐induced an ∼10% PV contraction that was accompanied by a reduction in total circulating protein mass, whereas diuretic fluid loss and total body water remained unchanged.Our data support an oncotically driven fluid redistribution from the intra‐ to the extravascular space, rather than fluid loss, as the mechanism underlying HH‐induced PV contraction. Abstract Extended hypoxic exposure reduces plasma volume (PV). The mechanisms underlying this effect are controversial, possibly as previous studies have been confounded by inconsistent experimental conditions. Here, we investigated the effect of hypobaric hypoxia (HH) on PV in a cross‐over study that strictly controlled for diet, water intake, physical activity and temperature. Eleven males completed two 4‐day sojourns in a hypobaric chamber, one in normoxia (NX) and one in HH equivalent to 3500 m altitude. PV, urine output, volume‐regulating hormones and plasma protein concentration were determined daily. Total body water (TBW) was determined at the end of both sojourns by deuterium dilution. Although PV was 8.1 ± 5.8% lower in HH than in NX after 24 h and remained ∼10% lower thereafter (all P 0.23). Plasma renin activity and circulating aldosterone were suppressed in HH during the first half of the sojourn (all P 0.05). Markers for atrial natriuretic peptide were higher in HH than NX after 30 min (P = 0.001) but lower during the last 2 days (P, Key points Acclimatization to hypoxia leads to a reduction in plasma volume (PV) that restores arterial O2 content.Findings from studies investigating the mechanisms underlying this PV contraction have been controversial, possibly as experimental conditions were inadequately controlled.We examined the mechanisms underlying the PV contraction evoked by 4 days of exposure to hypobaric hypoxia (HH) in 11 healthy lowlanders, while strictly controlling water intake, diet, temperature and physical activity.Exposure to HH‐induced an ∼10% PV contraction that was accompanied by a reduction in total circulating protein mass, whereas diuretic fluid loss and total body water remained unchanged.Our data support an oncotically driven fluid redistribution from the intra‐ to the extravascular space, rather than fluid loss, as the mechanism underlying HH‐induced PV contraction.

High mountain ecosystems and their biota are governed by low-temperature conditions and thus can be used as indicators for climate warming impacts on natural ecosystems, provided that long-term data exist. We used data from the largest alpine to nival permanent plot site in the Alps, established in the frame of the Global Observation Research Initiative in Alpine Environments (GLORIA) on Schrankogel in the Tyrolean Alps, Austria, in 1994, and resurveyed in 2004 and 2014. Vascular plant species richness per plot increased over the entire period, albeit to a lesser extent in the second decade, because disappearance events increased markedly in the latter period. Although presence/absence data could only marginally explain range shift dynamics, changes in species cover and plant community composition indicate an accelerating transformation towards a more warmth-demanding and more drought-adapted vegetation, which is strongest at the lowest, least rugged subsite. Divergent responses of vertical distribution groups of species suggest that direct warming effects, rather than competitive displacement, are the primary causes of the observed patterns. The continued decrease in cryophilic species could imply that trailing edge dynamics proceed more rapidly than successful colonisation, which would favour a period of accelerated species declines.

The semi-micro technique of Bredon has several advantages over the standard method of the Fertilisers & Feeding Stuffs Regulations. The former gives satisfactory results and, with proper equipment, can give four times as many crude fibre determinations as the latter in the same time. After application of the Dougall corrections for altitude, results by the semi-micro method showed comparatively small errors as compared with those by the official method (determinations at 3750 and 6800 ft. altitude), and are acceptable for routine analyses.

The ultraviolet‐A (UVA) part of the solar spectrum at the Earth's surface is an essential environmental factor but continuous long‐time monitoring of UVA radiation is rarely done. In Austria, three existing stations of the UV monitoring network have been upgraded with UVA broadband instruments. At each station, one instrument measures global UVA irradiance and—in parallel—a second instrument measures diffuse irradiance. Recent and past measurements are available via a web page. This paper describes the used instruments, calibration and quality assurance and control procedures. Global and diffuse UVA measurements during a period of up to 5 years are presented. Data indicate clear annual courses and an increase of UVA with altitude by 8–9% per 1000 m. In the first half of the year, UVA radiation is higher than in the second half, due to less cloudiness. In Vienna (153 m asl), the mean daily global UVA radiant exposure in summer is almost as high as at Mt. Gerlitzen (1540 m asl), equalizing the altitude effect, due to less cloudiness. However, in winter, the UVA radiant exposure at Mt. Gerlitzen is double as high, as in Vienna., The ultraviolet‐A (UVA) part of the solar spectrum at the Earth's surface is an essential environmental factor but continuous long‐time monitoring of UVA radiation is rarely done. In Austria, three existing stations of the UV monitoring network have been upgraded with UVA broadband instruments. At each station, one instrument measures global UVA irradiance and—in parallel—a second instrument measures diffuse irradiance. Recent and past measurements are available via a web page. This paper describes the used instruments, calibration and quality assurance and control procedures. Global and diffuse UVA measurements during a period of up to 5 years are presented.

Previous researches have examined the zooarchaeological record to understand changes in human diet in central western Argentina through time. This research has focused on variations in the relative abundance of large prey in archaeofaunal contexts. The observed changes were explained by a decrease in residential mobility, forced by both the intensification in the use of resources and the introduction of the first domesticated plants ca. 2000 years bp. In this paper, we revised archaeofaunal interpretations by taking into account zooarchaeological assemblages and human isotope records within the biogeographical distributions of prey in the region. Our results demonstrate that faunal diversity in zooarchaeological assemblages has a stronger correlation with the natural distribution of resources (especially with altitude) than with chronology, as was proposed previously. However, archaeofaunal information, including human isotopic data, suggests that a decrease in residential mobility, postulated in a previous paper, took place, modifying the expected diversity distribution throughout the landscape. Copyright © 2013 John Wiley & Sons, Ltd.

Within the Atmospheric Dynamics Mission Aeolus (ADM-Aeolus), the European Space Agency (ESA) has approved a Doppler wind lidar (DWL) to fly on a dedicated platform orbiting dawn to dusk at 400 km altitude, planned for launch in 2008. Rigorous design trade-offs have resulted in a lidar concept capable of delivering high-quality wind component profiles, but with a limited coverage. A companion paper describes the realistic simulation of this DWL, whereas this paper sets out to assess the impact of such a lidar in meteorological analyses and forecasts. To this end, an Observing System Simulation Experiment (OSSE) is run. The superior conventional observation coverage of 1993 is used to simulate all conventional observations, although a limited set of satellite observations is simulated. As a consequence, only the northern hemisphere DWL impact in the OSSE is assumed realistic. Here, over a 15-day period with variable weather, out of 15 daily forecasts, 14 show beneficial impact of the DWL. Although the experiment is limited, it corroborates other practical and theoretical evidence that the ADM DWL will demonstrate a beneficial impact in meteorological analyses and forecasts. Copyright © 2006 Royal Meteorological Society

This paper discusses the quantification of vertical surface displacements by means of grid-based digital elevation models (DEMs). The surface changes are quantified by comparing altitude and different topographic parameters, which have a geomorphic significance with respect to surface changes. This paper describes the choice of different spatial calculation techniques, considering DEM accuracy and the propagation of error for the different topographic parameters involved. The techniques are illustrated on two grid-based DEMs from Finsterwalderbreen, a 35 km2 sized valley glacier on south-western Spitzbergen, Norwegian High Arctic.

The objective of this paper is to focus on the influence of clouds and wind on air and road surface temperature variations between different types of local climate environments. The study area covers 160×130 km2 and includes 35 field stations in the Swedish Road Weather Information System (RWIS) and two synoptic weather stations. By combining data from the two sources, the spatial and temporal variations in air and road surface temperature have been analysed. In the first part of this paper the theoretical influence of different weather parameters is determined. In the empirical part of the study, a validation of the theoretical result is assessed using temperature and weather data from the study area. The results show that it is possible to calculate the temperature variations in relation to topographical siting and different weather factors. During day-time conditions, the effect of screening from the sun has a significant influence on the road surface temperature, even with cloudiness amounting to 4–6 octas, provided that the solar elevation is high. During night-time, the potential for pooling of cold air is determined by cloud cover and wind speed. When cloudy situations prevail during night-time, neutral stability is dominant resulting in a decrease with increasing altitude for both air and surface temperatures. Road surface temperatures, however, have a lower correlation with altitude than air temperature. The variation in surface temperature decreases with altitude is also larger and has a more even distribution than the air temperature decrease with altitude. Wind speed was not an important factor for the variation in surface temperature decrease with altitude, but insolation from the sun during day-time is one parameter to consider. Copyright © 2000 Royal Meteorological Society

The Schmidt hammer has for some years been used to measure the hardness of different rock surfaces and to date relatively boulders in moraine deposits. In this paper applications on isostatically raised boulder-beaches and rocky shores are described. The research area is the northern Swedish Bothnian coast where present isostatic uplift is between 0.8-1.0 cm year−1. Elevations above sea-level can be converted to a timescale. Rebound values (R) of the Schmidt hammer are correlated with the altitude and the degree of rock weathering can be estimated for each site. Eight sites with boulder-beaches and nine sites with rocky shores have been analysed. For boulder-beaches correlation-coefficients of 0.82-0.97 for weathering values (R) and the elevations above sea-level were obtained. For the rocky shores these values were calculated to 0.75-0.97. This method has applications in both geomorphology and archaeology. For example, a deep layer of weathered dolerite in the Nordingra region, which previously has been regarded as a post-Weichselian formation, can be shown to be of pre-Weichselian origin. Several archaeological applications are also mentioned in the paper.

SummaryHigh-altitude areas are important socio-economical habitats with ruminants serving as a major source of food and commodities for humans. Living at high-altitude however is extremely challenging predominantly due to the exposure to hypoxic conditions, but also because of cold temperatures and limited feed for livestock. To survive at high-altitude environments over the long-term, ruminants have evolved adaptation strategies, e.g. physiological and morphological modifications, which allow them to cope with these harsh conditions. Identification of such selection signatures in ruminants may contribute to more informed breeding decisions, and thus improved productivity. Moreover, studying the genetic background of altitude-adaptation in ruminants provides insights into a common molecular basis across species and thus a better understanding of the physiological basis of this adaptation. In this paper, we review the major effects of high altitude on the mammalian body and highlight some of the most important short-term (coping) and genetically evolved (adaptation) physiological modifications. We then discuss the genetic architecture of altitude adaptation and target genes that show evidence of being under selection based on recent studies in various species, with a focus on ruminants. The yak is presented as an interesting native species that has adapted to the high-altitude regions of Tibet. Finally, we conclude with implications and challenges of selection signature studies on altitude adaptation in general. We found that the number of studies on genetic mechanisms that enable altitude adaptation in ruminants is growing, with a strong focus on identifying selection signatures, and hypothesise that the investigation of genetic data from multiple species and regions will contribute greatly to the understanding of the genetic basis of altitude adaptation.

In the context of recent climate changes and their impact on the vegetation cover in the southern shore of the Mediterranean, this paper deals with the potential distribution in the present and the future of the Aleppo pine in the north‐east of Algeria. Accordingly, this study focuses on modelling of the spatiotemporal distribution of the Aurasian Aleppo pine, by means of MaxEnt program. The models developed with MaxEnt showed good predictivity with AUC > 0.80 for the RCP 4.5 and RCP 8.5 scenarios projected, respectively, for 2055 and 2085. The results showed that the annual thermal amplitude followed by altitude appear to be the main factors of the spatiotemporal distribution of Aleppo pine in the study area. Under current conditions, only 20% of the territory seems favourable to the presence of the Aleppo pine. However, future predictions expect an extension of the areas classified as “moderately favourable” to the Aleppo pine. In response to climate changes, the Aurasian Aleppo pine may display two contrasted tendencies: a progressive evolution in the north, and a regressive evolution in the south of the Aures region as well as a displacement of suitable areas for Aleppo pine to the north.

If a community and its substrate are raised by tectonic uplift, the species present can either die out in the area, survive in situ unchanged, or survive in situ with adaptation and differentiation. The large-scale passive uplift of plant and animal populations during mountain-building is accepted in a growing number of studies, but the idea has seldom been examined critically. If passive uplift does occur, it has implications for interpreting community structure and speciation in some of the most biodiverse places on Earth, tropical mountains. It would also provide a simple explanation for many altitudinal anomalies, such as the occurrence of typical coastal elements at unusually high altitudes in certain localities. Examples include the coastal saltmarsh plant Salicornia at 4200 m altitude in the rapidly uplifted Andes, coastal frogs and ferns in African mountains, and inland mangroves in New Guinea. The first aim of this paper is to review previous work on passive uplift worldwide and the main ideas that have been discussed. A second goal is to discuss possible tests of passive uplift.

This data set reports woody plant species abundances in a network of 96 sampling sites spread across 22 000 km2 in the central Western Ghats region, Karnataka, India (74°15′–75°40′ E; 15°15′–13°30′ N). Due to its varied climate and diverse topography, the study area, which is part of the Western Ghats–Sri Lanka biodiversity hotspot, supports a wide array of non-equatorial tropical habitats including wet evergreen, moist and dry deciduous, and intact as well as degraded forests and scrublands. These formations, floristically moderately rich and diversified, are characterized by a lower rate of endemism than in the southern part of the Western Ghats. This data paper provides abundance and girth data for 76 813 trees and lianas of 446 species collected in 96 sampling sites during 1996–1997. A total of 61 965 individuals ≥10-cm girth at breast height (gbh) were recorded in 96 1-ha macroplots, while 14 848 individuals 1 m height, were sampled in three 0.1-ha microplots located within each macroplot. Additional data regarding the stand structure (average canopy height, percent canopy cover, number of strata) and the level of degradation are available for the macroplots, along with environmental data derived from other sources and analyses, such as soil types, rainfall, length of the dry season, and altitude. These data have been used to produce ecological research papers, as well as to elaborate conservation value maps and recommendations toward sustainable management of the forests of the central Western Ghats region. The complete data sets corresponding to abstracts published in the Data Papers section of the journal are published electronically in Ecological Archives at 〈http://esapubs.org/archive〉. (The accession number for each Data Paper is given directly beneath the title.)

We obtained spatially extensive canopy height measurements using airborne remote sensing to characterize the structure and dynamics of a tropical rain forest landscape. Light detection and ranging (LiDAR) is a remote-sensing technology that acquires measurements of canopy height and ground elevation. By recording the return time of laser pulses emitted by aircraft-mounted sensors, LiDAR systems quantify the structure and geometry of individual trees and canopy height and enable estimation of the vertical and horizontal distribution of biomass using millions of accurate height measurements. This data set contains 127 849 839 records from 128 square kilometers of tropical wet forest in the Atlantic lowlands of Costa Rica (mean sampling density is 1.99 observations/m2). The study area includes all 16 square kilometers of mixed-land-use forest at the La Selva Biological Station and the lower flanks of Braulio Carrillo National Park. It contains a mosaic of historical and contemporary land use that is representative of contemporary tropical forest landscapes. Field studies demonstrated that LiDAR measurements were precise and accurate throughout the topographic and structural conditions at the site. Each record includes: easting and northing mapped coordinates (UTM Zone 16 North), height above ground (m), interpolated ground elevation (m), and six remote-sensing descriptors (point classification, the return number, the number of returns for the given pulse, intensity, scan angle, and the time of emission of the laser pulse). The data can be applied to a wide range of questions in basic and applied science, and are a valuable resource from a well-studied tropical rain forest for teaching and education. They also provide a quantitative baseline against which future conditions can be assessed. The complete data sets corresponding to abstracts published in the Data Papers section of the journal are published electronically in Ecological Archives at 〈http://esapubs.org/archive〉. (The accession number for each Data Paper is given directly beneath the title.)

Oxygen ions, O+, efficiently energized by weak fast shock in the mid-altitude cusp observed by Cluster on 7 November 2004 are investigated in this paper. An interplanetary fast shock hitting Earth ...

We read with interest the paper from Millet et al. (2021), which discuss reports suggesting that high-altitude residence may be beneficial in the novel coronavirus disease (COVID-19). They conclude that no evidence-based knowledge is presently available on whether and how altitude/hypoxia may prevent, treat, or aggravate COVID-19. They suggest that the reported lower incidence and mortality of COVID-19 in high-altitude places observed by others (Stephens et al., 2021) remain to be confirmed. Stephens et al. (2021) study two groups: one living in counties located at altitudes less than 914 m and the other at altitudes higher than 2133 m...

Studies assessing air temperature variations and their dependence on altitude from the eastern side of the Antarctic Peninsula are sparse. In this paper, we analyse air temperature and near-surface lapse rates from the Ulu Peninsula (James Ross Island, Antarctic Peninsula). The temperature data were acquired from nine sites both in ice-free areas and glaciers of the Ulu Peninsula in 2013–2016. The most important factors influencing air temperature differences were sea-ice conditions, topography and ground surface properties.

Determining the susceptibility of species to changing thermal niches is a major goal for biologists. In this paper we develop an eco-physiological model of extinction risk under climate change premised on behavioral thermoregulation. Our method downscales operative environmental temperatures, which restrict hours of activity of lizards, hr , for present-day climate (1975) and future climate scenarios (2070). We apply our model using occurrence records of 20 Phrynocephalus lizards (or taxa in species complexes) drawn from literature and museum records. Our analysis is phylogenetically informed, because some clades may be more sensitive to rising temperatures. The limits for computed hr predict local extirpations among Phrynocephalus lizards at continental scales and delineate upper boundaries of thermal niches as defined by Extreme Value Distributions. Under the 8.5 Representative Concentration Pathway scenario, we predict extirpation of 64% of local populations by 2070 across 20 Phrynocephalus species, and 12 are at high risk of total extinction due to thermal limits being exceeded. In tandem with global strategies of lower CO2 emissions, we propose regional strategies for establishing new national parks to protect extinction-prone taxa by preserving high-elevation climate refugia within existing sites of species occurrence. We propose that evolved acclimatization - maternal plasticity - may ameliorate risk, but is poorly studied. Previous studies revealed that adaptive maternal plasticity by thermoregulating gravid females alter progeny thermal preferences by ±1 °C. We describe plasticity studies for extinction-prone species that could assess whether they might be buffered from climate warming - a self-rescue. We discuss an epigenetic framework for studying such maternal-effect evolution.

Background: Texture is important in the preferences of apple consumers. Of the pre-harvest factors affecting fruit quality and especially texture, altitude and subsequent climatic conditions are crucial, determining differences in the physiological mechanisms of fruit growth, ripening stage and chemical composition, as demonstrated by several studies. This work applies a detailed sensory-instrumental protocol developed in a previous paper to investigate the impact of altitude, time of harvest and their cross-effect on sensory characteristics of apple, with a focus on texture.; Results: Sensory differences were found in relation to altitude, although the profile results were mainly affected by the time of harvest. Fruit from lower altitude was described as juicier, crunchier and sweeter than samples from higher altitude, which were floury, sourer and more astringent. Texture performance, soluble solids content and titratable acidity corroborated this sensory description. Moreover, anatomical data showed that fruit from lower altitude had a larger volume, a higher number of cells and a higher percentage of intercellular spaces.; Conclusion: We demonstrated that differences between fruit from various altitudes can be perceived through human senses, and that the proposed sensory-instrumental tool can be used to describe such differences. This study brings more understanding about the impact of altitude and time of harvest on apple sensory properties. This work could support apple producers, from semi-mountainous regions (Alps, Tyrol, etc.), in advertising and valorising their products with their specific characteristics in a more efficient manner. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Glacial activity affects landscape evolution in some parts of mountainous Greece. This paper deals with the southern part of Mount Olympus where the geomorphological impacts of Pleistocene glaciations are well presented. It is a preliminary study to demonstrate the landscape that has evolved as a result of glacial activity in these uplands. For this purpose, detailed field work and large-scale geomorphological mapping were performed. A 25-m sediment core was retrieved from the study area on which preliminary lithological and micropalaeontological–palaeobotanical analyses were performed. The intense glacial activity of the southern Mount Olympus area produced a number of landscape changes. Three cirques were identified in the uplands whose evolution has led to the formation of various types of moraines (ground, lateral, medial and terminal) down to an altitude of 1677 m. Intense glacio-fluvial activity caused a major reconfiguration of the drainage network in this area and also caused the formation of a lake. The occurrence of a water body in the area is documented by the presence of aquatic vegetation in parts of a 25-m core retrieved from this former lake basin. In recent times, the lake overtopped the fluvial deposits that bounded it, incising them and leading to the emptying of the lake.

For a distance of about i00 miles (i6o km.) southward from Monterey, California, the coast of the Pacific is closely skirted by an irregular series of elevations known collectively as the Santa Lucia Mountains. The range varies from 25 to 30 miles (40 to 48 km.) in width and is bounded on the east by the valley of the Salinas River. A considerable number of peaks and ridges rise to more than 3500 ft. (io66 m.) elevation, and the highest summit, Junipero Serra Peak, reaches 5844 ft. (1781 m.). The Santa Lucias are almost devoid of arable valleys, the slopes are steep and closely set, and much of the vegetation is difficult to penetrate, at the same time that the heavily forested areas are few and difficult of access. For these reasons they have remained thinly settled and little modified by farming and lumbering operations. The few farms that are to be found south of the Carmel River either occupy terraces along the sea or else the rounded summits or ridges within a few miles of the ocean. The character and ecological distribution of the vegetation in the Santa Lucias is influenced by the proximity of the sea on the west, by the relatively arid conditions of the Salinas Valley on the east, by the topographically controlled moisture conditions, by altitude, slope exposure and the mineralogical origin of the soils. The sharp local contrasts in vegetation which are everywhere so conspicuous in California, are here found in a marked degree. Heavy forests of redwood, several types of chaparral, and a semi-arid winter grassland may often be found within the limits of a single square mile. For several years the writer has devoted portions of the summer months to an examination of the vegetation of the Santa Lucias, and to several lines of instrumentation. Attention has been devoted chiefly to the portion of the range lying north of Point Sur and the Arroyo Seco, and the most intensive work has been done in the vicinity of Palo Colorado Canyon and Rocky Creek, about 12 miles south of Carmel. The aim of this paper is to describe briefly the principal types of vegetation and their distribution. A subsequent paper in this journal will be devoted to the results of the instrumentation carried on in the northern end of the Santa Lucias, and a consideration of the physical conditions. My best thanks are due to Dr. D. T. MacDougal for his sustained interest in the work, to Dr. H. M. Hall for assistance in determination of plants, and to Mr. Magnus Gregerson and Mr. Fremont Ballou for valuable help in instrumentation.

This paper investigates the ability of five different data-driven methods, artificial neural networks (ANNs), adaptive neuro-fuzzy inference system (ANFIS) with grid partition (GP), ANFIS with subtractive clustering (SC), support vector regression (SVR) and gene expression programming (GEP), in predicting long-term monthly temperatures by using data from 50 stations in Iran. The periodicity component (month of the year), station latitude, longitude and altitude values were used as inputs to the applied models to predict the long-term monthly temperatures. The overall accuracy of the SVR model was found to be better than that of the other models. The GEP model gave the worst estimates. The maximum determination coefficient (R2) values were found to be 0.996, 0.999, 0.997 and 0.959 for the ANN, ANFIS-GP, ANFIS-SC and GEP models in Karaj and Qazvin stations, respectively. The highest R2 value (0.999) of SVR model was found for the Tabas station. The minimum R2 values were respectively found as 0.988, 0.946 and 0.985 for the ANFIS-GP, ANFIS-SC and SVR models in Bandar Abbas station while the ANN and GEP models gave the minimum R2 values of 0.982 and 0.886 in the Abadan and Kerman stations, respectively. The results indicated that the long-term monthly temperatures of any site can be successfully estimated by data-driven methods applied in this study using geographical inputs. The interpolated maps of temperatures were also obtained by using the optimal SVR model and evaluated in the study. The temperature maps showed that the highest temperatures were occurred in the southeastern and central parts of the Iran.

Urban heat island (UHI) effect is an important impact factor of the regional climate and ecological environment. How to observe and analyse the spatial distribution of UHI has become an important issue of urban environmental research. In this paper, the near-surface air temperature of Beijing was derived based on the Landsat/TM satellite imagery on 26 July 2011 to study the near-surface UHI. A statistical model at 195-m window size was established to estimate the air temperature, using land surface temperature, normalized difference vegetation index, altitude, and surface albedo as independent variables. The mean absolute error (MAE) of the model was 0.87°C, and the R2 was 0.66, indicating that the method can be used to effectively estimate the air temperature. The air temperature distribution obtained from remote sensing revealed that the UHI effect in Beijing was very significant and showed a concentrated pattern. The heat island intensity was stronger in the southern part than in the northern part of the city. In addition, the relationship between the air temperature and impervious surfaces was analysed. The air temperature increased with increasing impervious surface coverage, and the rate of change depended on the impervious surface coverage. When the impervious surface coverage was below 40 per cent, the temperature increased rapidly with increasing impervious surface coverage, and when the impervious surface coverage was above 40 per cent, the temperature increased slowly. This study provides a new approach to monitor near-surface UHI and reveals its relationship with impervious surface, providing a scientific reference for urban planning and environmental assessment.

The immense and towering Tibetan Plateau (TP) acts as a heating source and shapes the climate of not only the Eurasian continent but also the entire world. The mass elevation effect of the TP was first observed in the 1950s; however, due to the scarcity of meteorological observation stations and limited climatic data, little information on the mass elevation effect of the plateau and its implications for the position of Alpine treelines in the southeastern part of the TP is quantitatively known. This paper compares monthly mean air temperature differences at elevations of 4000, 4500, 5000, 5500 and 6000m between the main plateau, the Qilian Mts. in the northeastern corner of the plateau and the Sichuan Basin to the east of the plateau to quantify the mass elevation effect of the plateau. The TP air temperature data are retrieved from Terra moderate-resolution imaging spectroradiometer (MODIS) land surface temperature (LST), and the free-air temperatures over the westernmost Sichuan Basin are estimated using the measured lapse rate from Mt. Emei, which is located in the western portion of the Sichuan Basin. The results demonstrate the following important characteristics. (1) Owing to the mass elevation effect, air temperatures gradually increase from the eastern edge to the interior main TP. The monthly mean air temperature in the interior main plateau is approximately 2-7 degrees C higher than in the surrounding mountains and adjacent lowland areas. At an elevation of 4500m (corresponding to the mean altitude of the TP), the monthly mean temperature differences between the plateau and the Sichuan Basin range from 3.58 degrees C (April) to 6.63 degrees C (June); the monthly temperature differences between the plateau and the Qilian Mts. range from 1.6 degrees C (July) to 7.7 degrees C (March). (2) The mass elevation effect of the plateau pushes the 10 degrees C isotherm upward in the warmest month and is indicative of a warmth index of 15 degrees C month up to elevations of 4600-4700 m, which enables the treeline altitude in the interior TP 500-1000m higher than along the eastern edge. Therefore, mass elevation effect contributes to the occurrence of the highest treeline in the Northern Hemisphere, which is present on the southeastern TP.

Several decades of human activities have severely impacted braided rivers worldwide. Despite their widespread disappearance, some remnant braided sectors are still held in the French Rhone basin, mainly in the south-east of France. In this paper, we analyse the evolutionary pattern of 53 braided reaches, focusing on the active channel width and island patterns, by comparing aerial photographs from the 1950s and 2000s (Institut Geographique National). Because different braided patterns exist (e.g. bar versus island-braided), we tested the relative effect of geographical and temporal factors. The hypothesis is that three main biogeomorphological braided types exist (i.e. defined through the presence, the amount and the relative size of vegetated islands), based on the combined effect of the following: (i) their position along the river network (i.e. river gradient, altitude and sediment regime) and (ii) the temporal effect represented by the time since the last large flood, that is, the recent flood history. Our results show that even if the regional context (climate and sediment regime mainly) plays a key role, the temporal factor, represented by recent flood history, seems to heavily influence the response of the width pattern and vegetation recovery. Local factors (i.e. topography and groundwater) may also have an impact, but their influence has no effect at the regional level. These results support braided river management (conservation and/or restoration actions) in the Rhone basin and provide a better understanding of the range of braided rivers' functioning. Further studies (e.g. multidate retrospective survey) are needed to better understand the role of flood events on braided pattern and vegetation recovery. Copyright © 2013 John Wiley & Sons, Ltd.

Air temperature as a major climatic component is important in land evaluation, water resources planning and management, irrigation scheduling and agro-hydrologic planning. In this paper, the capabilities of Adaptive Neuro-Fuzzy Inference System (ANFIS) and Artificial Neural Networks (ANNs) were evaluated in predicting long-term monthly air temperature values at 30 weather stations of Iran. Monthly data of 20 weather stations were used for training and 10 stations' data were used for testing. Consequently, the periodicity component, station latitude, longitude and altitude values were introduced as input variable to predict the long-term monthly temperature values. The estimates of the ANFIS and ANN models were compared with each other with respect to root mean-squared error, mean absolute error and determination coefficient statistics. The ANN models generally performed better than the ANFIS model in the test period. For the ANN model, the maximum and minimum determination coefficient values were found to be 0.995 and 0.921 in Semnan and Bandar-e-Abbas meteorological stations, respectively. The maximum and minimum determination coefficient values were found as 0.999 and 0.876 for the ANFIS model in Shiraz and Bandar-e-Abbas stations. Copyright © 2013 Royal Meteorological Society

This paper presents a classification of different natural flow regimes found in Ebro basin, one of the largest in the Mediterranean region. Determination of flow regimes was based on multivariate analyses using long-term discharge series of unaltered flow data. Mean monthly discharges of the 30 ‘best’ flow series and a total of 52 flow series containing unaltered flow data were selected to represent baseline flow conditions for tributaries throughout the basin. Metrics representing magnitude, duration and frequency components of flow were used to identify hydrologic differences across the basin. A total of six natural flow regimes were identified in the Ebro Basin, using a Ward cluster method. The flow patterns identified and their spatial distribution largely corresponded with climatic zones previously reported for the Ebro Basin, with regime types ranging from pluvio-oceanic in the western part of the basin to Mediterranean in the eastern region. Geologic characteristics of the catchment and altitude of headwaters were also found to play an important role in defining flow regime type. A 19-hydrologic variable subset was used to explain main hydrologic differences among groups (such as magnitude and frequency of extreme flow conditions or magnitude and variance of average flow conditions). However, stepwise discriminant analysis was not able to identify consistent subsets of hydrologic variables that adequately identified the six natural flow regime types in this basin. Canonical discriminant analysis was useful to understand class separation and for the interpretation of results. Copyright © 2012 John Wiley & Sons, Ltd.

This paper is to investigate the effect of altitude on Jet A's flash point using the experimental method. Firstly, the vapor pressure of four fuels is measured by saturated steam pressure tester with ND-1 pressure sensor in the low-pressure environment under nine different temperatures, and the results show that the Clausius–Clapeyron relationship between vapor pressure and temperature is applicable to the multicomponent mixture. Secondly, the BS-1 closed bomb apparatus is used to measure the oil samples, and the hypobaric chamber is applied to change the environment pressure from 55to 101.3 kPa. The flash point is found to decrease nonlinearly with the altitude increasing on the basis of the notion of a critical value of fuel–air mass ratio equals to 0.065 at the minimum flammability limit. Only when the atmospheric pressure approximates normal atmosphere does the flash point decrease linearly with the increase in altitude. This discovery agrees well with J.E. Shepherd's research. Thence, the experiment results provide scientific data for the safety of aircraft tank and benefit fire protection, such as inflammable liquid transport, storage, and so on, in oil pipeline management. Copyright © 2012 John Wiley & Sons, Ltd.

The relationship between the mass transfer in the Earth and vertical deformation can be studied using continuous relative gravimetry and continuous GPS observations. Compared to mobile relative gravimetry and absolute gravimetry, continuous relative gravimetry permits to monitor the whole process of gravity changes and mass transfer, avoiding the problems from low measurement precision and temporal resolution. In this paper, more than 13000 hours gravity data recorded at the Jiufeng seismic station using the superconducting gravimetry (SGC053) are analyzed along with the data of co-located absolute gravimetry, air pressure, vertical displacement of surrounding GPS stations, WUHN IGS site and WHJF site, GRACE monthly time-variable gravity and two global continental water storage models (GLDAS, CPC). Gravity variations affected by solid earth tide, air pressure, pole tide and continental water loading are corrected using the harmonic analysis method, atmospheric pressure admittance model, pole tide model and the correlation analysis with GRACE results and/or water storage models, then instrument drift is also corrected using co-located absolute gravity measurements. Based on the above processing, the relationship between the residual gravity time series and GPS vertical deformation is addressed. The harmonic analysis result for SGC053 gravity records, spanning about one and half years, shows that the white noise is about (1.14~1.40)×10–8 m·s–2 and the tidal factor error of dominant tidal groups reach about 0.10/00. Compared to ocean tide loading (3×10–8 m·s–2), the gravity due to air pressure (12×10–8 m·s–2) and pole tide (10×10–8 m·s–2) is much large. The drift of SGC053, about 2.18×10–8(m·s–2)/a, is estimated using 4 absolute gravity co-located records of FG5-232. The result shows that the residual gravity caused by continental water loading in summer and autumn is about (6~8) × 10–8 m·s–2, by comparing residual gravity variations with both GARCE result and global continental water loading (GLDAS, CPC). Gravity variations corrected by water loading show a perfect negative correlation with the vertical deformation of the GPS station, about 15 km away from SGC053, so as to data in spring and winter. And the vertical crustal deformation is subsidence and the gravity change rate is about 1.79×10–8 (m·s–2)/a. The ratio of the changes in gravity and altitude related to the local vertical crustal movement is about –354×10–8 (m·s–2)/m.

Stomatal characteristics are used as proxies of paleo-environment. Only a few model species have been used to study the mechanisms of genetic and environmental effects on stomatal initiation. Variation among species has not been quantified. In this paper, results from an in situ reciprocal transplant experiment along an elevation gradient in the northeast Tibetan Plateau are reported, in which the relative effects of genetics (original altitude) and environment (transplant altitude) on stomatal density (SD) and length (SL) were quantified. In Thalictrum alpinum, only the environment significantly influenced SD, with the variance component () of the environment found to be much greater than that of genetics () (). In Kobresia humillis, only genetics significantly influenced SD and SL, with the genetics variance component found to be greater than that of the environment (, for SD). These results suggest that the extent to which genetics and the environment determine stomatal initiation and development is species-specific. This needs to be considered when studying genetic or environmental controls of stomatal initiation, as well as when SD and SL are used as proxies for ancient climate factors (e.g., CO2 concentration).

The signal of a hypersonic spacecraft entering the Earth's atmosphere may be lost at a certain altitude transitorily. This phenomenon is called "blackout," an important performance feature of aircraft design. Recently, with the development of the nearcraft, communication techniques under the plasma environment have increasingly become more important, with the realization that we can record, monitor, track, and capture the nearcraft. In this paper, an idea based on the capability of radiation from the terahertz communication system to penetrate the plasma sheath is proposed to provide the theoretical basis for real-time communication with the nearcraft. Copyright © 2012 John Wiley & Sons, Ltd.

South Asia covers more than 30° of latitude with weather observation stations situated from 6°N at Galle, Sri Lanka, to 36°N at Chitral in Pakistan. Moreover, the South Asian station network ranges in altitude from sea level to nearly 4000 m above sea level. This paper uses time series of 11 objectively defined indices of daily temperature extremes at 197 stations in Bangladesh, India, Nepal, Pakistan and Sri Lanka to examine the possible impacts of elevation and latitude on changes in temperature extremes over the period of 1971-2000. Trends in extreme indices are consistent with general warming only at low altitudes and latitudes. Stations at high altitudes and latitudes show both positive and negative trends in extreme temperature indices. As a notable example, the Diurnal Temperature Range (DTR), which has been known to decrease in most parts of the globe, has increasing trends over many high altitude stations in South Asia. Trends in extreme temperature indices at stations in South Asia higher than 2000 m above sea level are mostly in disagreement with those reported over the Tibetan Plateau. Observed trends at low altitude locations in South Asia suggest that these sites can generally expect future changes in temperature extremes that are consistent with broad-scale warming. High-elevation sites appear to be more influenced by local factors and, hence, future changes in temperature extremes may be less predictable for these locations.

In this paper I describe a simple numerical procedure to compute synthetic horizon altitude profiles for any given site. The method makes use of a simplified model of local Earth's curvature, and it is based on the availability of digital elevation models describing the topography of the area surrounding the site under study. Examples constructed using the Shuttle Radar Topographic Mission (SRTM) data (with 90 m horizontal resolution) are illustrated, and compared to direct theodolite measurements. The proposed method appears to be reliable and applicable in all cases when the distance to the local horizon is larger than ∼10 km, yielding a rms accuracy of ∼0.1 degrees (both in azimuth and elevation). Higher accuracies can be achieved with higher resolution digital elevation models, like those produced by many modern national geodetic surveys (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Recent research in the Ivane Valley has shown that it was first occupied during the late Pleistocene between 43-49,000 years cal. BP, making this area one of the earliest colonised in Papua New Guinea. At an altitude of 2000 metres above sea level, occupation also marks the first time that modern humans pushed into the high altitude montane regions within Sahul. Part of the process of familiarisation with a landscape involves the identification of lithic sources. The importance of lithic sources for the landscape learning process is that, unlike plant foods and animals, it can be assumed that the colonisers had little a priori knowledge of their location before arriving in a particular landscape. If lithic sources are available, then their successful use would require a process of learning the locations and properties of the different raw material sources, thus creating an intimate level of knowledge of a landscape. By examining how modern humans familiarised themselves with the Ivane landscape through the use of lithic sources, we may be able to understand further the processes of colonisation and adaptation to particular landscapes. Keywords: colonisation, stone tools, raw material sources, Ivane, Papua New Guinea ********** New research in the Ivane valley (Summerhayes et al. 2010, 2009), located within the Owen Stanley Ranges of Papua New Guinea, has pushed back initial colonisation of this site to between 43,000-49,000 years cal. BP, placing it within the earliest stages of occupation of Papua New Guinea and thus Sahul. The significance of this early occupation is that, at almost 2000 metres above sea level, the Ivane valley is located within a high altitude environment, which during the late Pleistocene, was located close to the treeline, at a junction between montane forest and subalpine grasslands (Hope 2009). The colonisation of this valley marks the first time in the Sahul region that modem humans move into this type of high altitude environment. The importance of this occupation is that it may have required new adaptations to not only an unfamiliar landscape, but also to an unfamiliar habitat. This paper will examine the process of familiarisation with a landscape, what Rockman (2003) terms as "landscape learning", through examining how people both colonised and adapted to specific landscapes over time, using a geoarchaeological data set of lithic sources. With a subsistence technology involving the use of stone tools, the location and quality of these sources would have been important resources to initially identify. The importance of lithic sources for the landscape learning process is that, unlike plant foods and animals, it can be assumed that the colonisers had little a priori knowledge of their location before arriving in a particular landscape. If lithic sources are available within a landscape, then their successful use would require a process of learning the locations and properties of the different raw material sources, thus creating an intimate and detailed knowledge of a landscape. This familiarisation process may then provide further insights into the strategies used by modem humans to colonise and adapt to particular landscapes. Learning the lithic landscape The exploitation of new environments and habitats in Sahul suggests that changes in subsistence strategies will occur as modem humans become familiar with new resources such as plant foods and a marsupial fauna. Part of the process of changing the focus of subsistence strategies is learning the landscape; becoming more familiar with the specific resources available and how they can be used. Part of that landscape includes the lithic sources, which are only found at fixed locations, meaning that no previous knowledge of their location or qualities can be assumed prior to moving into a particular landscape. In order to use these sources successfully, a process of familiarisation of landscape must occur, where time is taken to locate and test different types of raw materials before selecting appropriate raw materials for use. …

A number of disciplines are involved in the collection and interpretation of Holocene palaeoenvironmental data from coastal lowlands. For stratigraphic frameworks and the assessment of relative sea-level (RSL) change, many non-specialists rely on existing regional models. It is, however, important that they are aware of major developments in our understanding of the factors controlling coastal change and of the potential sources of error in sea-level reconstructions. These issues are explored through a critical evaluation of a new sea-level curve presented by Behre (2003, 2007) for the southern North Sea. In contrast to most sea-level curves published from this region over the last 20 years, the curve shows strong fluctuations that are interpreted as representing vertical movements of sea level. We present a detailed examination of the data used by Behre. From this analysis it is clear that many of the data points used are unsuitable for high-resolution (centimetre or decimetre) sea-level reconstruction. This paper also gives an overview of possible sources of error with respect to the age and altitude of sea-level index points and of changes in our understanding of the processes that underpin the interpretation of the organic and occupation levels used as index points. The constraints on the spatial scale over which sea-level reconstructions can be applied (changes in palaeotidal range and crustal movements) are also considered. Finally, we discuss whether the large-amplitude centennial-scale sea-level fluctuations proposed by Behre can be reconciled with the known mechanisms of sea-level change and other recent high-resolution studies from this region. We conclude that such fluctuations are highly unlikely to be real features of the sea-level history of the southern North Sea. © 2011 The Authors. Boreas © 2011 The Boreas Collegium.

This paper describes the hydrological changes caused by inter-basin water transfer and the reservoir development on the hydrological regimes of two rivers. The Sabljaki Reservoir in the Zagorska Mrežnica River and the Bukovik Reservoir in the Upper Dobra River began operation in 1959. Both are part of the hydroelectric power plant (HEPP) Gojak, which installed capacity is 50 m3/s. Their water volumes at the spillway altitudes of 320.10 m a. s. l. and 320.15 m a. s. l. are 3.3 × 106 m3 and 0.24 × 106 m3 respectively. Both the Dobra and Mrežnica Rivers are at the same time losing, sinking and underground karst rivers. A 9376 m long tunnel provides water from the Sabljaki Reservoir to the HEPP Gojak which was constructed in the Lower Dobra River. The Sabljaki Reservoir is located in the Plaški karst polje while the Bukovik Reservoir is located in the neighboring Ogulin karst polje. The consequences of the inter-basin water transfer are strong and abrupt changes in the hydrological regimes of the downstream sections of both rivers. At the same time, the construction and development of the both reservoirs caused hydrological changes to the upstream section of the Upper Dobra River.

This paper presents an observational and experimental study of the basking behaviour and heat exchange rate of the montane lizard Lacerta monticola. The results obtained by these procedures were coupled in order to understand behavioural mechanims promoting effective thermoregulation at high altitudes. Heating rate was higher when body size was smaller, and substrate temperature and sun rays incidence angle were higher. The lizards cooled faster when body size and substrate temperature were lower, and when the body temperature of the lizard going into shadow was higher. Time exposed to sun and mean duration of basking periods were longer early in the morning, while bask frequency increased through the morning. Our results suggest that time devoted to basking is mainly obtained by regulating bask duration. Lizards obtained the necessary time for heating by means of long basking periods. Mean travel distance per minute and distance to the nearest refuge increased from early morning to midday. These behavioural variables were tightly correlated with the expected heating rate of individuals. Body size affects thermoregulatory behaviour as well as locomotor activity. Juvenile lizards, with small body mass and high surface-to-volume ratios, were subjected to faster heating and cooling rates, basked more frequently than adults (but during shorter periods), and devoted more time to locomotion than adults. The thermoregulatory behaviour of L. monticola is the result of the combination of shuttling heliothermy by basking and the exploitation of thermal opportunities offered by patches in shade through thermal exchange with the substrate.

Research on influence of non-tectonic or non-seismic factors on thermal radiation of land surface has an important practical significance to using satellite thermal infrared remote sensing to detect seismic precursors or fault activity. In land surface temperature (LST), which can be obtained from satellite images, there exist two kinds of typical non-tectonic or non-seismic components: annual variation produced by the solar radiation, and the longtime stable contents related with topography, latitude and energy balance on the land surface. The sum of these two typical components is defined as the normal annual variation field (NAVF) of land surface temperature. In this paper, the annual variation field of LST in China is extracted by using the wavelet method based on the LST data from 2000 to 2008. Then, quantitative expresion of NAVF is gotten by heat theory and the mathematic physical method. Furthermore, the quantitative relationships between temperature and altitude or latitude are obtained: temperature decreases by 0.51±0.01K with altitude rising 100 m, and temperature decreases 0.77±0.08K with latitude rising 1 degree. In sum, NAVF can be used as a background to analyze anomalies of thermal radiation, and the relationship between temperature and altitude or latitude can used to correct effects of terrain and latitude variations on LST.

A complex aeromagnetic anomaly in Southern Apennines (Italy) is analysed and interpreted by a multiscale method based on the scaling function. We use multiscale methods allowing analysis of a potential field along ridges, which are lines defined by the position of the extrema of the field at the considered scales. The method developed and applied in this paper is based on the study of the scaling function of the total magnetic field. It allows recovering of source parameters such as depth and structural index. The studied area includes a Pleistocene volcanic structure (Mt. Vulture) whose intense dipolar anomaly is superimposed on a longer wavelength regional anomaly. The interpretation of ridges of the modulus of the analytic signal at different altitude ranges allows recognition of at least three distinct sources between about 5 km and 20 km depth. Their interpretation is discussed in light of borehole data and other geophysical constraints. A reasonable geological model for these sources indicates the presence of intrusions, probably linked to the past activity of Mt. Vulture.

Stable isotope measurements in precipitation help us to form the basic inference about the origin and the state of water in different environments. The precipitation samples collected during the South West Monsoon (SWM) during August 2007 from 37 different locations in the state help in deriving the first preliminary local meteoric water line (LMWL) for the Tamil Nadu State. The study reveals that there are three main sources of water vapours, namely South East Arabian Sea (SEAS), Indian Ocean (IO) and evaporation from local water bodies. There are wide variations in the altitude and amount of rainfall received in the state. It is also noted that there is a significant variation in the latitude and the distance from the coast. Hence, an attempt is made in this paper to study the factors controlling the composition of stable isotopes in precipitation with reference to amount of rainfall, latitude, altitude and the continental effect. The altitude and continental effect shows good correlation to the variations in stable isotope composition. Copyright © 2009 John Wiley & Sons, Ltd.

This paper reports on a study analysing the spatial distribution functions, the correlation structures, and the power spectral densities of high-resolution LIDAR snow depths (∼1 m) in two adjacent 500 m × 500 m areas in the Colorado Rocky Mountains, one a sub-alpine forest the other an alpine tundra. It is shown how and why differences in the controlling physical processes induced by variations in vegetation cover and wind patterns lead to the observed differences in spatial organization between the snow depth fields of these environments. In the sub-alpine forest area, the mean of snow depth increases with elevation, while its standard deviation remains uniform. In the tundra subarea, the mean of snow depth decreases with elevation, while its standard deviation varies over a wide range. The two-dimensional correlations of snow depth in the forested area indicate little spatial memory and isotropic conditions, while in the tundra they indicate a marked directional bias that is consistent with the predominant wind directions and the location of topographic ridges and depressions. The power spectral densities exhibit a power law behaviour in two frequency intervals separated by a break located at a scale of around 12 m in the forested subarea, and 65 m in the tundra subarea. The spectral exponents obtained indicate that the snow depth fields are highly variable over scales larger than the scale break, while highly correlated below. Based on the observations and on synthetic snow depth fields generated with one- and two-dimensional spectral techniques, it is shown that the scale at which the break occurs increases with the separation distance between snow depth maxima. In addition, the breaks in the forested area coincide with those of the corresponding vegetation height field, while in the tundra subarea they are displaced towards larger scales than those observed in the corresponding vegetation height field.

This paper presents results from seven isolation basins to investigate the relative sea-level history from the Lateglacial and the mid to late Holocene from the Bjarkarlundur area near Reykholar on the Reykjanes peninsula in North West Iceland. Results presented help to constrain the timing and rate of relative sea-level (RSL) change since deglaciation and also the timing of deglaciation itself in the Bjarkarlundur area. The marine limit is estimated to be approximately 80 m above sea level based on an isolation basin with sill altitude at 79.1 m. The maximum age of this marine limit and, hence, local deglaciation is estimated at 12.2 14C ka BP. Relative sea level then fell rapidly during the late Bolling–early Allerod at a rate of approximately −35 mm 14C a−1 to below 50 m by 11.4 14C ka BP. After this the rate of RSL fall decreased significantly during the late Allerod and Younger Dryas Chronozones (averaging −6 mm 14C a−1 between 11.4 and 9.7 14C ka BP). Based on isolation basins with sill altitudes of 51.1 and 41.1 m, our data constrain any possible fluctuation in RSL produced by regrowth of ice during the Younger Dryas to below 10 m. After 9.7 14C ka BP the rate of RSL fall increased significantly to approximately −23 mm 14C a−1 to at least 9.0 14C ka BP. If eustatic sea-level rise is taken into account and the calibrated timescale is used, actual crustal uplift rates are estimated at +56 and +46 mm cal. a−1 during Lateglacial and early Holocene times, respectively. During the mid to late Holocene RSL then rose to at least 1 m above present-day levels, gradually falling to the present-day level from 3.1 14C ka BP. These results demonstrate the potential of isolation basin data for investigating the timing and rate of RSL change in Iceland. This can add important well-constrained information on RSL when combined with data from raised beaches. Copyright © 2009 John Wiley & Sons, Ltd.

In order to provide further insights into the relationships between the tropopause and different mandatory levels, this paper discusses the coupling between standardized tropopause height anomalies (STHAs) and standardized 500-hPa and 100-hPa height anomalies (S5HA5 and S1HAs, respectively) within the 'climatic year' for three sets of upper-air stations located approximately along 20 degrees S, 30 degrees S and 45 degrees S. Data used in this research consists in a radiosonde database spanning the period 1973-2007. The mandatory levels are supposed to be included in each radiosonde profile. The tropopause, on the other hand, is calculated from the significant levels available for each sounding using the lapse rate definition. After applying a selection procedure, a basic statistical analysis combined with Fourier analysis is carried out in order to build up the standardized variables. Empirical orthogonal functions (EOFs) in S-mode are used to get the normal modes of oscillation as well as their time evolution, for STHA/S5HA as well as for STHA/S1HA coupling, separately, within the aforementioned latitudes. Overall, there are definite cycles in the time evolution associated with each EOF structure at all three latitudes, the semi-annual wave playing the most important role in most of the cases. Nevertheless, 20 degrees S seems to be the only latitude driven by diabatic heating cycles in the middle atmosphere. Certainly, EOF1 at this latitude has a semi-annual behaviour and seems to be strongly influenced by the tropical convection seasonality. Apparently, the convectively driven release of latent heat in the middle troposphere affects the time evolution of the EOF1 structure. By contrast, the vertical propagation of planetary waves is raised as a possible explanation for the EOF1 and EOF2 behaviour at latitudes beyond 20 degrees S, in view of the close connection existent between the semi-annual oscillation (SAO) and the reversion in the direction of the zonal wind. Copyright (C) 2009 Royal Meteorological Society

This paper provides some insights on the quasi-biennial oscillation (QBO) modulated 11-year solar cycle (11-yr SC) signals in Northern Hemisphere (NH) winter temperature and zonal wind. Daily ERA-40 Reanalysis and ECMWF Operational data for the period of 1958-2006 were used to examine the seasonal evolution of the QBO-solar cycle relationship at various pressure levels up to the stratopause. The results show that the solar signals in the NH winter extratropics are indeed QBO-phase dependent, moving poleward and downward as winter progresses with a faster descent rate under westerly QBO than under easterly QBO. In the stratosphere, the signals are highly significant in late January to early March and have a life span of similar to 30-50 days. Under westerly QBO, the stratospheric solar signals clearly lead and connect to those in the troposphere in late March and early April where they have a life span of similar to 10 days. As the structure changes considerably from the upper stratosphere to the lower troposphere, the exact month when the maximum solar signals occur depends largely on the altitude chosen. For the low-latitude stratosphere, our analysis supports a vertical double-peaked structure of positive signature of the 11-yr SC in temperature, and demonstrates that this structure is further modulated by the QBO. These solar signals have a longer life span (similar to 3-4 months) in comparison to those in the extratropics. The solar signals in the lower stratosphere are stronger in early winter but weaker in late winter, while the reverse holds in the upper stratosphere. Copyright (C) 2009 Royal Meteorological Society

Utilizing the earth and near-grade environment as a source of energy has historically been a common practice. Beyond solar and wind, designers do not usually look towards the sky as the source of additional benefits. The objective of this paper was to make tall-building designers more aware of the additional sources of sustainability ‘in the sky’; how these sources change with altitude; and how this knowledge can benefit the design, construction and operation of tall buildings. Exterior environmental factors including temperature, presssure/air density, solar, wind and moisture, and their relationships with altitude are discussed. Selected approaches are suggested on how to benefit from them. Since current energy codes and ‘green’ building standards do not address the issue of enrironmental variations with altitude, the sky has potential to offer unique energy-saving opportunities and possibly add to the quantified sustainability of a tall building. Where possible, a speculative 1-km (3281 ft) tall tower in Dubai is used as an example for illustration. Copyright © 2008 John Wiley & Sons, Ltd.

Summary This paper sets out the results of fairly regular observation of Oreotrochilus chimborazo on Mt Cotopaxi between 1964 and 1967. The species is found between 13,000 and 15,000 ft in a small area just south of the Equator where it nests on cliffs. Climate, terrain, food and nesting are described. Breeding continues throughout the year. Particular attention is given to the importance of nesting sites in this harsh climate and the consequent tendency towards colonial* nesting in favoured spots. The high degree of segregation between the sexes is also considered. A brief account is given of the O. chimborazo population in the Guamani pass on the rim of the Amazon basin, where climate and terrain have produced some differences in breeding habits.

This paper identifies an anomaly between the currently acccpted isobasc pattern for raised shorelines in Scotland. which is a simple ellipsoid centred over the Western Highlands, and current models for the morphology of the Late Devensian ice-sheet. which show a primary dome in the Western Highlands but a prominent secondary dome over the Southern Uplands. One explanation of this anomaly is that it is an artefact of inadequate shoreline data for south-west Scotland. To test this hypothesis, altitude data on the Main Rock Platform in the Firth of Clyde area have been collected and analysed. and demonstrate patterns that probably result from the influence of Southern Upland ice. The ice-sheet models in this area are therefore supported.