Coral bleaching indices and thresholds for the Florida Reef Tract, Bahamas, and St. Croix, US Virgin Islands

It is well established that elevated sea temperatures cause widespread coral bleaching, yet confusion lingers as to what facet of extreme temperatures is most important. Utilizing long-term in situ datasets, we calculated nine thermal stress indices and tested their effectiveness at segregating bleaching years a posteriori for multiple reefs on the Florida Reef Tract. The indices examined represent three aspects of thermal stress: (1) short-term, acute temperature stress; (2) cumulative temperature stress; and (3) temperature variability. Maximum monthly sea surface temperature (SST) and the number of days >30.5 °C were the most significant; indicating that cumulative exposure to temperature extremes characterized bleaching years. Bleaching thresholds were warmer for Florida than the Bahamas and St. Croix, US Virgin Islands reflecting differences in seasonal maximum SST. Hind-casts showed that monthly mean SST above a local threshold explained all bleaching years in Florida, the Bahamas, and US Virgin Islands.     

Late Cretaceous marine reptiles (Elasmosauridae and Mosasauridae) of the Chatham Islands, New Zealand

A new marine reptile record for the Upper Cretaceous of the Chatham Islands is described from the Takatika Grit. Incomplete mosasaur and plesiosaur remains represent the first record of marine reptiles from the Chatham Islands and wider New Zealand. Present among the myriad bones are elasmosaurid plesiosaurs and mosasaurine mosasaurs. This assemblage is comparable to the New Zealand marine reptile record and represents apex predators that flourished in a zone of upwelling in a Late Cretaceous southern high-latitude ecosystem.     

金门地区海岸阶地研究

海岸阶地的形成通常是海平面变动、地壳变动或两者共同作用之结果．对于海阶的研究除了可印证推论古气候、往昔海平面变化及地壳变动状况,还可藉以了解各区域间变动的差异,全盘了解大地构造的意义;小规模的海阶变动,时常与地震活动伴生,因此,研究海阶更可作为判读地震周期的依据之一．世界各地位于地壳活动带的国家对海阶的形态与演育过程均作详细的调查及研究．距今2亿年前的三叠纪晚期的一系列构造运动,形成福建沿海地区的区域变质带和长乐一南澳断裂带,由于构造运动的影响,于断裂带东缘形成了一系列岛屿,金门列岛的形成,与中国东南沿海的造山运动有着密切关系,皆受到影响而产生变动．金门地区的海阶,共有11段阶地,海拔依序为0～10m、15～25m、30～45m、50—65m、70—80ITI、90～120in、130—154m、160～165m、190～208m、215～225m、230～250m,依据晚更新世海阶序列与隆升率关系对比基图迭合法的推估,各段阶地的年代分别为6kaBP、46kaBP、57kaBP、64kaBP、80kaBP、100kaBP、103kaBP、120kaBP、176kaBP、190kaBP、202kaBP,除了第一阶为全新世时期所形成,其余皆为更新世时期的产物,针对金门列岛海阶的高度与间距做对比,得知该区的平均隆升速率为1．3mm／a．     

1997年11月南沙群岛调查海区的跃层特征

本文对１９９７年１１月南沙海区综合考察的标准层资料运用三次样条插值函数法,计算了调查海区的温、盐两种跃层所处的深度及各自的厚度和强度,并进行了相应的分析,特别对季节性温、盐跃层的示性特征,进行了讨论。分析研究发现：所有测站均存在温跃层和盐跃层,其中多跃层超过５０％,跃层的强度和厚度呈相对应的关系,即厚度大（小）的地方强度小（大）。还用连续观测资料对温度日跃层进行了简单的描述,并分析了日温跃层特笥与     

Modelling diatom responses to climate induced fluctuations in the moisture balance in continental Antarctic lakes

The water chemistry of lake systems on the edge of the Antarctic continent responds quickly to changes in the moisture balance. This is expressed as increasing salinity and decreasing lake water level during dry periods, and the opposite during wet periods. The diatom composition of the lakes also changes with these fluctuations in salinity and lake water depth. This is important, as their siliceous remains become incorporated into lake sediments and can provide long-term records of past salinity using transfer functions. In order to develop transfer functions, diatoms and water chemistry data were inter-calibrated from five different East Antarctic oases, namely the Larsemann Hills, the Bølingen Islands, the Vestfold Hills, the Rauer Islands and the Windmill Islands. Results indicate that salinity is the most important environmental variable explaining the variance in the diatom flora in East Antarctic lakes. In oligo- saline lakes the variance is mainly explained by lake water depth. This dataset was used to construct a weighted averaging transfer function for salinity in order to infer historical changes in the moisture balance. This model has a jack-knifed r² of 0.83 and a RMSEP of 0.31. The disadvantage of this transfer function is that salinity changes in oligo-saline lakes are reconstructed inaccurately due to the edge effect and due to the low species turnover along the salinity gradient at its lower end. In order to infer changes in the moisture balance in these lakes, a second transfer function using weighted averaging partial least squares (with two components) for depth was constructed. This model has a jack-knifed r² of 0.76 and a RMSEP of 0.22. Both transfer functions can be used to infer climate driven changes in the moisture balance in lake sediment cores from oligo-, hypo-, meso- and hyper-saline lakes in East Antarctic oases between 102–75°E. The transfer function for lake water depth is promising to track trends in the moisture balance of small freshwater lakes, where changes in shallow and deep-water sediments are readily reflected in changing diatom composition.     

Reply to ‘Comment on: Rainfall,fog and throughfall dynamics in a subtropical ridge top cloud forest,National Park of Garajonay (La Gomera,Canary Islands,Spain)’ by A. Ritter and C.M. Regalado

This Reply aims to clarify and address many of the errors introduced to the discussion of our original paper (García‐Santos and Bruijnzeel, 2011; referred to henceforth as GSB2011) in the comment by Ritter and Regalado (2012) (henceforth referred to as RRR2012) as explained more fully under replies nos. 1–6, 8–12 and 14–18 below. Two (largely inconsequential) shortcomings in our original paper as detected by RRR2012 are acknowledged (see replies nos. 7 and 13 below). It is concluded that the majority of the comments offered by RRR2012 are unfounded as well as unnecessary. In summary, the two errors in GSB2011 spotted by RRR2012 (see points 7 and 13 below) could easily have been addressed in an erratum. Copyright © 2013 John Wiley & Sons, Ltd.     

Marine resource conservation and prospects for environmental sustainability in Anuta, Solomon Islands

It has been argued that atolls have abundant, varied and dependable marine resources and that atoll-dwellers' exploitation of marine fauna has remained essentially constant since prehistoric times. According to that line of argument, modern technology, in and of itself, has had little effect on the relationship between human populations and the natural environment. A countervailing view contends that the market economy and reliance upon money have disrupted egalitarian socioeconomic systems and threatened the long-standing ecological balance. Here I consider questions of environmental sustainability and economic viability on Anuta, a Polynesian outlier in Solomon Islands. Anuta, a volcanic island, has more abundant terrestrial resources than do atolls, and all indications are that it has been a hierarchically-organized chiefdom for well over a dozen generations. Nonetheless, it is a small, seemingly vulnerable community. In reality, productivity of land and sea have remained stable at least since the 1970s, in part because of conscious, purposeful decisions intended to preserve the island's natural resources. Thus, Anutans can be described as conservationists in the technical sense used by some authors. Yet on Anuta, as elsewhere, a combination of population growth and market exchange has begun to place a strain on the environment and raises questions for their system's long-term viability.     

Improving understanding of the spatial dimensions of biophysical change in atoll island countries and implications for island communities: A Marshall Islands’ case study

Using coarse-scale approaches, existing national assessments of vulnerability and adaptation highlight physical land instability as a major threat to atoll island nationhood. However, such evaluations are bereft of detailed, ground-truthed analyses of the physical impacts of climatic change on reef islands, treating islands as homogenous in both biophysical and social characteristics. The distinct geomorphic context of two proximate reef islands (Jeh and Jabat) in the Marshall Islands was examined through conventional land survey techniques. A template documenting the nuances in island topography was used to evaluate simple inundation scenarios, reflecting current and future sea-level changes under storm surge conditions. The variations in local scale community exposure to inundation were discernible. The study highlights the importance of treating coarse-scale assessments with caution and underscores the need for continued commitment to resolving variations in community experiences to environmental change. Notions of risk and exposure are complex and embedded in both the biophysical and social contexts of each island community. Despite a number of targeted urban vulnerability studies in the Pacific there remains a need for efforts to document localised differences in experience to better inform contemporary adaptation efforts.     

An unusual ‘blood rain’ over the Canary Islands (Spain). The storm of January 1999

An intense storm, including strong winds, a dust storm, ‘blood rain’ and heavy rains affected the Canary Archipelago between 5 and 10 January 1999, producing damage valued at 156 million euros. The present paper analyses the weather conditions and sedimentological features of the dust. The resulting data provide a possible explanation of palaeoclimatic conditions essential for the stabilization of sand dunes in the eastern parts of the Canary Islands.