A hundred years of Norwegian exploration of the polar regions

Nanscn's crossing of Greenland in 1888 galvanized Norwegians to a leading role in polar exploration. Subsequent expeditions include Nanscn's ‘Fram’ drift (1893-1896), Otto Sverdrup to Arctic Canada (1898-1902) and Roald Amundsen through the North-west Passage (1903-1906). Systematic exploration of Svalbard started in 1906. Norwegian Antarctic activities include Larsen's exploration of the Weddell Sea (1894), Borchgrcvinck's Antarctic expedition (1898-1900) and Amundsen at the South Pole (1911). Norwegian polar activities up to the present have resulted in about 200 topographic and thematic maps. Norwegian polar experience has led to efficient and safe operations, and Norwegian ships are preferred by many nations.     

近50年南海西沙地区的气候变化特征研究

采用西沙台站1958~2005年基本气象观测资料,系统分析西沙地区近50a来主要气象要素(温度、降水、风速、日照和云量)变化特征。结果表明,近50a来年均地面气温增暖幅度约1.0℃,增温速率0.19℃/(10a),与全国平均的增温率接近。四季的平均气温也都呈上升趋势,其中冬季和春季的上升趋势最明显,秋季次之,夏季的变化最小。降水的波动性很大,年降水量变化趋势不明显,四季中只有春季降水呈明显增加趋势。地面风速主要呈减小的趋势,特别是在近30a年平均风速比常年值明显偏小。四季风速均减小,尤其在秋、冬季。年日照时数、总云量均呈显著下降趋势,而低云量略有增加。     

A "critical" climatic evaluation of last interglacial (MIS 5e) records from the Norwegian Sea

Sediment cores from the Norwegian Sea were studied to evaluate interglacial climate conditions of the marine isotope stage 5e (MIS 5e). Using planktic forminiferal assemblages as the core method, a detailed picture of the evolution of surface water conditions was derived. According to our age model, a step-like deglaciation of the Saalian ice sheets is noted between ca. 135 and 124.5 Kya, but the deglaciation shows little response with regard to surface ocean warming. From then on, the rapidly increasing abundance of subpolar forminifers, concomitant with decreasing iceberg indicators, provides evidence for the development of interglacial conditions sensu stricto (5e- ss ), a period that lasted for about 9 Ky. As interpreted from the foraminiferal records, and supported by the other proxies, this interval of 5e- ss was in two parts: showing an early warm phase, but with a fresher, i.e., lower salinity, water mass, and a subsequent cooling phase that lasted until ca. 118.5 Kya. After this time, the climatic optimum with the most intense advection of Atlantic surface water masses occurred until ca. 116 Kya. A rapid transition with two notable climatic perturbations is observed subsequently during the glacial inception. Overall, the peak warmth of the last interglacial period occurred relatively late after deglaciation, and at no time did it reach the high warmth level of the early Holocene. This finding must be considered when using the last interglacial situation as an analogue model for enhanced meridional transfer of ocean heat to the Arctic, with the prospect of a future warmer climate.     

Wavelet analysis of quasi-3-year temperature oscillations in China in last 50 years, and predicted changes in the next 20 years

The wavelet analysis method is used to analyze the annual and winter temperature data of 98 observation stations in China in eight climate zones during the last 50 years （1961-2009）. The periodicities of temperature changes are investigated, and the possible temperature change trends in China in the next 20 years （2012-2029） are also predicted. Our results show that in the inter-annual temperature variability there are pervasive quasi-3- to quasi-4-year cycles, and these cycle changes are relatively steady. The periodic characteristics of the annual temperature changes are clearly different between northern and southern China, and our period superimposition extrapolation shows that both annual and winter temperatures in China will continue to increase in the next 20 years, more so in northern China and in the Qinghai-Xizang Plateau （QXP） than in the southern region, except in the southwest. If temperatures follow historic increasing linear trends, the overall temper- ature is expected to increase by 1℃ between 2010 and 2029.     

Climate variability and maize production in Cameroon: Simulating the effects of extreme dry and wet years

The effects of interyear variability of extreme rainfall events on maize yields at locations in Cameroon, in central‐west sub‐Saharan Africa were investigated through a simulation assessment combining a weather generator with a crop growth model. This study analyzes the potential of using dry/wet year predictions to reduce risk in subsistence agricultural production associated with climate variability at the site level. Weather data sets from eight provincial study localities were classified into three precipitation scenarios – dry (lower threshold), normal and wet (upper threshold) years. According to the modelling results, there is a less than 12 per cent variance in mean maize yields across six out of the eight localities when planting occurs in March, May and August. The variance is equivalent to approximately 100–300 kg per ha, which represents a significant amount of food in the household security of the majority impoverished sectors of rural and urban society, and which could greatly impact the socioeconomic activities of the entire populace. The results lead to the conclusion that all extreme dry and wet years are not equal in terms of their regional manifestation. This calls for precise monthly and sub‐seasonal local level forecasts and the effective dissemination of this information to farming communities in Cameroon, thereby facilitating the adaptive management of indigenous cropping practices and reducing their vulnerability to climate related disasters.     

开都河流域上下游过去50 a气温降水变化特征分析

利用开都河流域上下游4个气象台站（上游巴音布鲁克,下游焉耆、和静、和硕）1960-2009年的气温、降水资料,采用趋势分析与距平等统计方法,分析了近50 a来开都河流域的主要气象要素变化特征。研究发现：（1）1960-2009年开都河流域上下游年平均气温均呈明显上升趋势,增长强度分别为0.27 ℃/10 a和0.22 ℃/10 a。2000年后气温升高尤其显著,上游和下游的气温分别较50 a平均水平偏高0.97 ℃和0.69 ℃。该流域年最高温没有明显增加,而上下游年最低气温分别上升0.41 ℃/10 a和0.61 ℃/10 a,并与年平均气温有较好的相关性。通过对不同年代际各月气温的分析,发现该地区气温季节性特征在过去50 a发生了明显的变化。主要表现为冬季气温总体上升,夏季气温相对稳定,冬季与夏季温差逐渐减小,季节性呈变弱趋势。上游年代际间气温季节变化较下游更明显;（2）开都河流域降水主要集中在夏季,近50 a上下游降水量均呈增加趋势且上游达显著水平。上下游在降水分布及变化特征上有较大差异,上游年平均降水总量（273 mm）明显高于下游（77 mm）,且上游降水量增加强度（9.13 mm/10 a）高于下游（5.34 mm/10 a）。降水量年代际之间有一定差异,降水波动主要是在夏季,上游降水量的波动性大于下游。     

TEMPERATURE PROXY RECORDS COVERING THE LAST TWO MILLENNIA: A TABULAR AND VISUAL OVERVIEW

Proxy data are our only source of knowledge of temperature variability in the period prior to instrumental temperature measurements. Until recently, very few quantitative palaeotemperature records extended back a millennium or more, but the number is now increasing. Here, the first systematic survey is presented, with graphic representations, of most quantitative temperature proxy data records covering the last two millennia that have been published in the peer-reviewed literature. In total, 71 series are presented together with basic essential information on each record. This overview will hopefully assist future palaeoclimatic research by facilitating an orientation among available palaeotemperature records and thus reduce the risk of missing less well-known proxy series. The records show an amplitude between maximum and minimum temperatures during the past two millennia on centennial timescales ranging from c. 0.5 to 4°C and averaging c. 1.5–2°C for both high and low latitudes, although these variations are not always occurring synchronous. Both the Medieval Warm Period, the Little Ice Age and the 20th century warming are clearly visible in most records, whereas the Roman Warm Period and the Dark Age Cold Period are less clearly discernible.     

Salinity of surface waters in the Aral Sea region

An overview of recent changes in salinity in the surface waters of the Aral sea basin is given. Total dissolved salts (salinity) in most waters are higher than admissible values for drinking water, and ionic composition has changed with time. Salinity of the ‘Big Sea’ of the Aral was 48 g L⁻¹ in 1998, but has decreased to below 21 g L⁻¹ in the ‘Small Sea’ due to the building of a new dam between the two parts of the Aral Sea.     

Calanus in North Norwegian fjords and in the Barents Sea

The Physical environment of a North Norwegian fjord and of the Atlantic and Arctic domains of the Barents Sea are described. The seasonal variation of primary production and biomass of the most important copepod species are described in order to contrast regional differences in the timing of the plankton cycles. Analysis of the seasonal variation in the biomass of six different copepod species in Balsfjorden clearly demonstrate the importance of Calanus finmarchkus as a spring and early summer form, whereas Pseudoculanus acuspes , the most important smaller form, reaches the highest biomass later during the productive season. In the Atlantic part of the Barents Sea, C. finmarchkus is the dominant herbivorous form. The next most important species, Pseudocalanus sp. and M. longa , play a less important role here than in Balsfjorden. In the Arctic domain, the smaller copepod forms appear to have been replaced in trophodynamic terms by the youngest year-group (C-CIII) of C. glacialis , which prevails during the Arctic summer and autumn periods. The coupling between primary producers and Calanus on a seasonal basis is addressed through the grazing and the vertical organisation of the plant-herbivore community. The productivity of these two Calanus species is considered in relation to the seasonal and inter-annual variation in climate; although different mechanisms are utilised, cold periods tend to lower Calanus productivity both in the Arctic and the Atlantic domains of the Barents Sea. Interannual variations in Calanus biomass and productivity are discussed in the perspective of endemic and advective processes.     

近45 a来中国西北年极端高、低温的变化及对区域性增暖的响应

利用中国西北五省(区)1960-2004年129个台站逐日最低、最高温度资料,从中统计出年极端高温发生频次、年极端低温发生频次、年极端高温强度、年极端低温强度以及年极端高温和低温开始和结束日期,分析了它们近45 a来的变化情况。结果表明:近45 a来中国西北年极端高温发生频次的增加趋势是明显的,而年极端低温发生频次的减少趋势更显著;中国西北近45 a来年极端高温的强度在不断增强,而极端低温的强度在不断减弱;近45 a来中国西北年极端高温开始日期逐渐提前,结束日期逐渐推迟,而年极端低温的开始日期在逐渐推迟,结束日期在逐渐提前;年极端低温发生频次的减少对于西北区域增暖的响应比年极端高温发生频次增加更显著,而年极端低温强度的减弱要比年极端高温强度的增强对西北区域性增暖的响应偏弱,年极端高温发生频次的增加同年极端高温强度的增强对西北区域性增暖的响应程度基本相当。     

Influence of climate variability and human activities on stream flow variation in the past 50 years in Taoer River,Northeast China

Taoer River Basin, which is located in the west of Northeast China, is an agropastoral ecotone. In recent years, the hydrological cycle and water resources have changed significantly with the deterioration of the environment. Many water problems such as river blanking, wetland shrinking and salinization have occurred in this region. All of these phenomena were directly caused by changes in stream flow under climate variability and human activities. In light of the situation, the impact of climate variability and human activities on stream flow should be identified immediately to identify the primary driving factors of basin hydrological processes. To achieve this, statistical tests were applied to identify trends in variation and catastrophe points in mean annual stream flow from 1961 to 2011. A runoff sensitive coefficients method and a SIMHYD model were applied to assess the impacts of stream flow variation. The following conclusions were found: 1) The years 1985 and 2000 were confirmed to be catastrophe points in the stream flow series. Thus, the study period could be divided into three periods, from 1961 to 1985 (Period I), 1986 to 2000 (Period II) and 2001 to 2011 (Period III). 2) Mean annual observed stream flow was 31.54 mm in Period I, then increased to 65.60 mm in Period II and decreased to 2.92 mm in Period III. 3) Using runoff sensitive coefficients, the contribution of climate variability was 41.93% and 43.14% of the increase in stream flow during Periods II and III, suggesting that the contribution of human activities to the increase was 58.07% and 56.86%, respectively. 4) Climate variability accounted for 42.57% and 44.30% of the decrease in stream flow, while human activities accounted for 57.43% and 55.70% of the decrease, according to the SIMHYD model. 5) In comparison of these two methods, the primary driving factors of stream flow variation could be considered to be human activities, which contributed about 15% more than climate variability. It is hoped that these conclusions will benefit future regional planning and sustainable development.     

A temporal analysis of seasonal start dates across 25 urban environments in the eastern United States

This research examines changes to seasonal start dates (1948–2015) across urban locations in the eastern United States. For 25 cities, percentile-specific thresholds of temperature (T_a) and apparent temperature (AT) were used to define seasonal start dates. Seasonal changes were evaluated across four time periods: 0300, 0900, 1500, and 2100 UTC. Incorporating spatial and temporal variability into seasonal delineation, this research critiques the ways in which seasons are defined and builds on existing research regarding seasonal climate change. Both T_a and AT results generally indicate earlier starts to the summer and spring seasons, while the starts to winter and autumn seasons have been delayed. On average, a forward shift of 11 days was found for summer. Larger changes were found for AT thresholds when compared to air temperature alone. Temporally, the largest and most significant changes were found for the 0300 and 2100 observations. The observed changes to seasons have significant impact on a range of processes, including phenology and human health, and may be appropriate to consider further in future climatology studies.     

过去50年内蒙古极端气候事件时空格局特征

为了掌握内蒙古极端气候事件的发生趋势与时空格局,本文运用内蒙古自治区境内46个国家级气象站点的日值记录数据,计算与植被生长的水热条件及寒旱灾害直接相关的极端气候事件指数,分析过去50年内蒙古温度和降水气候事件的时空演变特征。研究结果表明,研究区极端温度事件的发生频率与持续时间迅速变化发生于20世纪90年代以来,60年代至80年代末呈平稳态势。表征低温事件的霜日日数（FD0）、冷昼日数（TX10p）、冷夜日数（TN10p）、冷持续指数（CSDI）等指数均呈现下降趋势,同时表征高温事件的夏日指数（SU25）、作物生长期（GSL）、暖昼日数（TX90p）、暖夜日数（TN90p）、热持续指数（WSDI）则均呈上升趋势。与极端高温事件发生频率的加剧在90年代初开始凸显不同,表征强降水事件发生频率和强度的极端降水指标的显著变化发生在近10年。研究区极端温度指数过去50年的变化过程几乎没有明显的空间分异特征,但是在位于农牧交错区的部分站点的强降水事件呈现出与大多数站点不同的特征,最近10年的强降水事件高于前一时段,而其他多数站点最近10年的极端降水指数均低于前一时段。     

Climate change effects at your doorstep: Geographic visualization to support Nordic homeowners in adapting to climate change

The complexity of climate information, particularly as related to climate scenarios, impacts, and action alternatives, poses significant challenges for science communication. This study presents a geographic visualization approach involving lay audiences to address these challenges. VisAdapt™ is a web-based visualization tool designed to improve Nordic homeowners’ understanding of climate change vulnerability and to support their adaptive actions. VisAdapt is structured to enable individual users to explore several climate change impact parameters, including temperature and precipitation, for their locations and to find information on specific adaptation measures for their house types and locations. The process of testing the tool included a focus group study with homeowners in Norway, Denmark, and Sweden to assess key challenges in geographic visualization, such as the level of interactivity and information. The paper concludes that geographic visualization tools can support homeowners’ climate adaptation processes, but that certain features, such as downscaled climate information are a key element expected by users. Although the assessment of interactivity and data varied both across countries and user experience, a general conclusion is that a geographic visualization tool, like VisAdapt, can make climate change effects and adaptation alternatives tangible and initiate discussions and collaborative reflections.     

The salinity tolerance of benthic invertebrates of the Aral Sea

Experiments to determine the upper limits of potential salinity tolerance of four species of Aral Sea benthic macroinvertebrates were carried out. Invertebrates of marine origin tolerate salinity increases up to 70–90 g L^–1, and the gastropodCaspiohydrobia, up to 100–110 g L^–1. It was concluded that the express-method based on the estimation of salinity resistance of isolated tissues cannot be used to estimate the limits of tolerance. The prediction is made that bivalve molluscs and polychaetes will remain in the Aral Sea until the salinity increases to 60–70 g L^–1, but perhaps gastropods will tolerate salinity increases to 100–110 g L^–1.     

The role of personal experiences in Norwegian perceptions of climate change

ABSTRACT

It is commonly assumed that personal experiences of a changing climate will influence people’s attitudes to the extent that they will be more likely to acknowledge anthropogenic climate change as a real threat and therefore be more willing to accept both mitigation and adaptation efforts. In the article, the authors examine how survey participants’ personal experiences of extreme events and climate-related changes in the natural environment influenced their perceptions of climate change. Using data from a nationally representative survey conducted in Norway in 2015 and the results of logistic regressions, the authors find that individual observations of changes in nature were linked to higher levels of concern with regard to climate change, as well as to attitudes that were more positive towards personal mitigation and adaption efforts. Somewhat counter-intuitively, they also find that participants who had personally experienced a natural hazard event were less concerned about climate change compared with participants without such experiences. The authors conclude that personal experience of the consequences of climate change may in some cases have a limited effect on enhancing people’s concerns about climate change.     

白令海夏季水文结构年际变化特征研究

基于2008、2010、2012和2014年我国北极科学考察期间在白令海获取的水文观测数据,结合历史共享资料,通过对白令海水团、上层海洋热含量、净热通量变化、风场及海平面气压分布情况等的分析,探讨了白令海水文结构的年际变化特征及其原因。研究发现,白令海夏季的水团包括白令海上层水团(BUW)、中层水团(BIW)、深层水团(BDW)和白令海陆架水团(BSW)。白令海温盐分布差异最大、年际变化最剧烈的情况主要集中在上层水团。对比4年水团分布情况,最明显的变化是2012年7月调查区上层海水温度偏低,2014年7月上层海水温度偏高。这种异常变化在热含量方面表现为:2012年7月调查区各个测站上的热含量异常低,而2014年7月测站上的热含量都高于平均水平。着重研究了2014年7月海温偏高的原因,认为是由于陆架和海盆区分别有两种不同的形成机制造成:陆架区累积净热通量偏高,海水吸收热量升温;海盆区在异常强大而持久的海面气压(SLP)高压系统下,海面负的风应力旋度得到加强,从而引起持续的暖平流输送及强烈的Ekman抽吸作用,最终导致了上层海水偏暖。     

Bacterial activities in the Dead Sea, 1980-1991: survival at the upper limit of salinity

Since the mass development of halophilic bacteria in 1980 and the subsequent decline of the community in 1982, no new mass development of bacteria has occurred in the Dead Sea, and bacterial numbers have remained extremely low. The lake’s salinity, and more specifically the divalent cation concentration, have increased greatly during the last ten years. To quantitate the activity of the community of heterotrophic bacteria in the Dead Sea water column, rates of incorporation of amino acids, glycerol, and acetate were measured, both during the 1980–1981 bloom and in recent years. With the development of the bloom, rates of incorporation amino acids, glycerol and acetate increased. Concomitant with the decline in bacterial numbers, the incorporation rates of amino acids and acetate decreased at the end of 1980-beginning of 1981, while glycerol incorporation rates remained high for one more year. Measurements in 1989 and in 1991 showed very low but significant incorporation rates (three to four orders of magnitude lower than during the 1980–1981 bloom). By the use of specific inhibitors, it was shown that the remaining activity was due to halophilic archaeobacteria. The mechanism of the long-term survival of a small active bacterial community in the Dead Sea in the absence of primary producers and other obvious sources of organic carbon, and at divalent cation concentrations greatly exceeding those enabling growth, is still unknown.