Computation of Windstorm Catalogues and Windstorm Severity Indices 1969-2013 for the UK and 11 UK Regions

This document outlines the methodology employed by the Climate Extremes Group in the Department of Space and Climate Physics at University College London (UCL) to identify and severity rank UK windstorms for the 45-year period from 1969 to 2013. The UCL methodology is underpinned by a robust UK windstorm definition that is applied to cleaned and homogenised continuous gust observations from 262 low-level station sites spread evenly around the UK. Windstorm catalogues and event severity rankings are provided for the whole UK and, uniquely, for each of 11 UK regions. The product’s background, input data, creation methods and output form are summarised under eight headings. References and appendix figures provide additional information

Methodology for Computation of UK Windstorm Gust Return Levels on a High Spatial Resolution (100 m) Grid

This document outlines the methodology employed by the Climate Extremes Group in the Department of Space and Climate Physics at University College London (UCL) to compute windstorm gust return levels (from 1 year to 1000 years) at high spatial resolution (100 m grid) for the whole UK. The methodology is summarised under eight headings. A ninth section addresses the precision of the gust return levels. A product format section, references and an appendix provide additional information

Fluctuations of a Greenlandic tidewater glacier driven by changes in atmospheric forcing : observations and modelling of Kangiata Nunaata Sermia, 1859–present

Acknowledgements. The authors wish to thank Stephen Price, Mauri Pelto, and the anonymous reviewer for their reviews and comments that helped to improve the manuscript. RACMO2.1 data were provided by Jan van Angelen and Michiel van den Broeke, IMAU, Utrecht University. MAR v3.2 data used for runoff calculations were provided by Xavier Fettweis, Department of Geography, University of Liège. The photogrammetric DEM used in Figs. 1 and 3 was provided by Kurt H. Kjær, Centre for GeoGenetics, University of Copenhagen. This research was financially supported by J. M. Lea’s PhD funding, NERC grant number NE/I528742/1. Support for F. M. Nick was provided through the Conoco-Phillips/Lundin Northern Area Program CRIOS project (Calving Rates and Impact on Sea Level).Peer reviewedPublisher PD

Global tropical cyclones and European windstorms in recent decline

Tropical cyclones worldwide and European windstorms (extratropical cyclones) are the main cause of great weather disasters worldwide but low confidence exists in the quantification and attribution of trends in these storms. This uncertainty is caused by limitations in the quality and quantity of historical data, by the presence of large year-to-year variability in storm counts and by an incomplete understanding of the mechanisms that cause trends. Here we reduce this uncertainty by clarifying the nature, significance and underlying causes of storm trends for the recent 1971 to 2010 period of generally sound surface windspeed data. We find that global tropical cyclones and European winter extratropical storms are mostly decreasing in annual frequency and accumulated power; for the periods 1981 to 2010 and 1991 to 2010 all trends are decreasing and in several cases significantly so. We attribute the recent significant decrease in global tropical cyclone activity to a trend towards colder ENSO (El Niño Southern Oscillation) conditions that produces anomalous zonal flows which tend to inhibit storm spin-up in the North Pacific. We attribute the recent significant decrease in UK and European winter windstorm activity to a decrease in North Atlantic tropospheric thermal wind associated with warmer winter air temperatures at polar and subpolar latitudes. Despite global temperatures rising by about 0.5°C since 1971 our results suggest that climate change has had no discernible positive impact on either globally averaged tropical cyclone activity or on European extratropical cyclone activity; indeed global warming may be contributing to the recent decrease in European extratropical storm activity

Terminus-driven retreat of a major southwest Greenland tidewater glacier during the early 19th century : insights from glacier reconstructions and numerical modelling

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A middle Eocene mesoeucrocodylian (Crocodyliformes) from the Kaninah Formation, Republic of Yemen

During the Cenozoic, the Arabian Plate separated from continental Africa and assumed a closer geographical relationship with Eurasia. As such, the vertebrate fossil record of the Arabian Peninsula has great potential for documenting faunal interchanges that occurred as a result of such tectonic events, with a shift from a primarily Afro-Arabian fauna in the Palaeogene to a more cosmopolitan fauna in the Neogene. Understanding of the sequence and timing of this faunal interchange has long been hampered by a lack of palaeontological data. Recently recovered fossils from the Middle Eocene Kaninah Formation of Yemen constitute the earliest Palaeogene record of continental vertebrates from the Arabian Peninsula, thereby offering a rare glimpse at the region’s post- -Cretaceous fauna. Here we describe fossil materials from the Kaninah Formation, a collection of dental and postcranial elements representing a mesoeucrocodylian crocodyliform of unclear affinities. The specimen exhibits ziphodont tooth morphology along with a biserial paravertebral shield and polygonal gastral osteoderms, consistent with certain mesoeucrocodylians (e.g., ziphodontan notosuchians). Yet the associated fragmentary anterior caudal vertebra, although badly abraded, preserves morphology suggestive of procoely. This vertebral type in combination with the dental and osteoderm morphology is much more taxonomically restrictive and consistent with the suite of characters exhibited by atoposaurids, a finding that would significantly extend that clade through the Cretaceous/Palaeogene boundary. Alternatively, given the relative paucity of information from the region during the Palaeogene, the combination of characteristics of the Kaninah crocodyliform may reflect a novel or poorly known form exhibiting previously unrecognised character mosaicism. We take a conservative approach, and refer the Kaninah specimen to Mesoeucrocodylia, Atoposauridae (?) pending discovery of more complete material. New fossils recovered from the Kaninah Formation raise unanticipated questions about the longevity of Mesozoic clades, underscoring the role that the region may play in revealing novel occurrences, relictual forms, and evidence of faunal dispersals from this critical interval in vertebrate evolutionary history

Differences in reproductive risk factors for breast cancer in middle-aged women in Marin County, California and a sociodemographically similar area of Northern California

<p>Abstract</p> <p>Background</p> <p>The Northern California county of Marin (MC) has historically had high breast cancer incidence rates. Because of MC's high socioeconomic status (SES) and racial homogeneity (non-Hispanic White), it has been difficult to assess whether these elevated rates result from a combination of established risk factors or other behavioral or environmental factors. This survey was designed to compare potential breast cancer risks and incidence rates for a sample of middle-aged MC women with those of a demographically similar population.</p> <p>Methods</p> <p>A random sample of 1500 middle-aged female members of a large Northern California health plan, half from Marin County (MC) and half from a comparison area in East/Central Contra Costa County (ECCC), were mailed a survey covering family history, reproductive history, use of oral contraceptives (OC) and hormone replacement therapy (HRT), behavioral health risks, recency of breast screening, and demographic characteristics. Weighted data were used to compare prevalence of individual breast cancer risk factors and Gail scores. Age-adjusted cumulative breast cancer incidence rates (2000–2004) were also calculated for female health plan members aged 40–64 residing in the two geographic areas.</p> <p>Results</p> <p>Survey response was 57.1% (n = 427) and 47.9% (n = 359) for MC and ECCC samples, respectively. Women in the two areas were similar in SES, race, obesity, exercise frequency, current smoking, ever use of OCs and HRT, age at onset of menarche, high mammography rates, family history of breast cancer, and Gail scores. However, MC women were significantly more likely than ECCC women to be former smokers (43.6% vs. 31.2%), have Ashkenazi Jewish heritage (12.8% vs. 7.1%), have no live births before age 30 (52.7% vs. 40.8%), and be nulliparous (29.2% vs. 15.4%), and less likely to never or rarely consume alcohol (34.4% vs. 41.9%). MC and ECCC women had comparable 2000–2004 invasive breast cancer incidence rates.</p> <p>Conclusion</p> <p>The effects of reproductive risks factors, Ashkenazi Jewish heritage, smoking history, and alcohol consumption with regard to breast cancer risk in Marin County should be further evaluated. When possible, future comparisons of breast cancer incidence rates between regions should adjust for differences in income and education in addition to age and race/ethnicity, preferably by using a sociodemographically similar comparison group.</p

The impact of reward and punishment on skill learning depends on task demands

Reward and punishment motivate behavior, but it is unclear exactly how they impact skill performance and whether the effect varies across skills. The present study investigated the effect of reward and punishment in both a sequencing skill and a motor skill context. Participants trained on either a sequencing skill (serial reaction time task) or a motor skill (force-tracking task). Skill knowledge was tested immediately after training, and again 1 hour, 24-48 hours, and 30 days after training. We found a dissociation of the effects of reward and punishment on the tasks, primarily reflecting the impact of punishment. While punishment improved serial reaction time task performance, it impaired force-tracking task performance. In contrast to prior literature, neither reward nor punishment benefitted memory retention, arguing against the common assumption that reward ubiquitously benefits skill retention. Collectively, these results suggest that punishment impacts skilled behavior more than reward in a complex, task dependent fashion