The environmental and evolutionary history of Lake Ohrid (FYROM/Albania): interim results from the SCOPSCO deep drilling project

Abstract. This study reviews and synthesises existing information generated within the SCOPSCO (Scientific Collaboration on Past Speciation Conditions in Lake Ohrid) deep drilling project. The four main aims of the project are to infer (i) the age and origin of Lake Ohrid (Former Yugoslav Republic of Macedonia/Republic of Albania), (ii) its regional seismotectonic history, (iii) volcanic activity and climate change in the central northern Mediterranean region, and (iv) the influence of major geological events on the evolution of its endemic species. The Ohrid basin formed by transtension during the Miocene, opened during the Pliocene and Pleistocene, and the lake established de novo in the still relatively narrow valley between 1.9 and 1.3 Ma. The lake history is recorded in a 584 m long sediment sequence, which was recovered within the framework of the International Continental Scientific Drilling Program (ICDP) from the central part (DEEP site) of the lake in spring 2013. To date, 54 tephra and cryptotephra horizons have been found in the upper 460 m of this sequence. Tephrochronology and tuning biogeochemical proxy data to orbital parameters revealed that the upper 247.8 m represent the last 637 kyr. The multi-proxy data set covering these 637 kyr indicates long-term variability. Some proxies show a change from generally cooler and wetter to drier and warmer glacial and interglacial periods around 300 ka. Short-term environmental change caused, for example, by tephra deposition or the climatic impact of millennial-scale Dansgaard–Oeschger and Heinrich events are superimposed on the long-term trends. Evolutionary studies on the extant fauna indicate that Lake Ohrid was not a refugial area for regional freshwater animals. This differs from the surrounding catchment, where the mountainous setting with relatively high water availability provided a refuge for temperate and montane trees during the relatively cold and dry glacial periods. Although Lake Ohrid experienced significant environmental change over the last 637 kyr, preliminary molecular data from extant microgastropod species do not indicate significant changes in diversification rate during this period. The reasons for this constant rate remain largely unknown, but a possible lack of environmentally induced extinction events in Lake Ohrid and/or the high resilience of the ecosystems may have played a role.

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The environmental and evolutionary history of Lake Ohrid (FYROM/Albania): Interim results from the SCOPSCO deep drilling project

10.5194/bg-2016-475 ◽

2016 ◽

Author(s):

Bernd Wagner ◽

Thomas Wilke ◽

Alexander Francke ◽

Christian Albrecht ◽

Henrike Baumgarten ◽

...

Keyword(s):

Environmental Change ◽

De Novo ◽

High Water ◽

Lake Ohrid ◽

Climatic Impact ◽

Deep Drilling ◽

Scientific Drilling ◽

Refugial Area ◽

Drilling Project

Abstract. This study reviews and synthesises existing information generated within the SCOPSCO ("Scientific Collaboration on Past Speciation Conditions in Lake Ohrid") deep drilling project. The four main aims of the project are to infer (i) the age and origin of Lake Ohrid (Former Yugoslav Republic of Macedonia/Republic of Albania), (ii) its regional seismotectonic history, (iii) volcanic activity and climate change in the central northern Mediterranean region, and (iv) the drivers of biodiversity and endemism. The Ohrid basin formed by transtension during the Miocene, opened during the Pliocene and Pleistocene, and the lake established de novo in the still relatively narrow valley between 1.9 and 1.3 Myr ago. The lake history is recorded in a 584 m long sediment sequence, which was recovered within the framework of the International Continental Scientific Drilling Program (ICDP) from the central part (DEEP site) of the lake in spring 2013. To date, 50 tephra and crypto-tephra horizons have been found in the upper 460 m of this sequence. Tephrochronology and tuning biogeochemical proxy data to orbital parameters revealed that the upper 247.8 m represent the last 637 kyr. The multi-proxy dataset covering these 637 kyr indicates long-term variability, with a change from cooler and wetter to drier and warmer glacial and interglacial periods around 300 ka. Short-term environmental change caused, for example, by tephra deposition or the climatic impact of millennial-scale Dansgaard-Oeschger and Heinrich events are superimposed on the long-term trends. Evolutionary studies on the extant fauna indicate that Lake Ohrid was not a refugial area for regional freshwater animals. This differs from the surrounding catchment, where the mountainous setting with relatively high water availability provided a refugial area for temperate and montane trees during the relatively cold and dry glacial periods. Although Lake Ohrid experienced significant environmental change over the last 637 kyr, preliminary molecular data from extant microgastropod species do not indicate significant changes in diversification rate during this period. The reasons for this constant rate remain largely unknown, but a possible lack of environmentally induced extinction events in Lake Ohrid and/or the high resilience of the ecosystems may have played a role.

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Introducing the Dynamic Destination Satisfaction Method: An Analytical Tool to Track Tourism Destination Satisfaction Trends with Repeated Cross-sectional Data

Journal of Travel Research ◽

10.1177/0047287520958205 ◽

2020 ◽

pp. 004728752095820

Author(s):

Andrea Guizzardi ◽

Marcello M. Mariani

Keyword(s):

Large Data ◽

System Level ◽

Set Covering ◽

Tourism Destination ◽

Cross Sectional ◽

Data Set ◽

Individual Level ◽

Specific Attribute ◽

The Matrix

This study introduces a new method, named Dynamic Destination Satisfaction Method (DDSME), to model tourists’ satisfaction with a destination (and its attributes), breaking it down into an individual-level component (linked to the specific individual tourists’ perceptions) and a system-level (time-related) component (common to all the tourists). Moreover, this work develops a matrix “entropy/trend accuracy” that destination managers can use to understand to what extent managing a specific attribute has increased tourists’ satisfaction with the destination over multiyear time spans. We test the innovative method on a large data set, covering the period 1997-2015 and including almost 0.8 million observations. By doing so, we analyze tourists’ satisfaction with tourism-related sectors and attributes of Italy as an inbound tourism destination and we use the matrix to map out destination attributes over time. The findings indicate that courtesy, art, and food are strategic attributes to enhance satisfaction in the long term.

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Party crashers? Modeling genuinely new party development paths in Western Europe

Party Politics ◽

10.1177/1354068820911355 ◽

2020 ◽

pp. 135406882091135

Author(s):

Vincenzo Emanuele ◽

Allan Sikk

Keyword(s):

Western Europe ◽

Original Data ◽

Set Covering ◽

Latent Growth ◽

Data Set ◽

New Parties ◽

Party Development ◽

Short And Long Term ◽

Development Paths

Western Europe has recently experienced the emergence of successful new parties, but while single parties or countries have been extensively studied, insufficient attention has been devoted to this phenomenon from a comparative and long-term perspective. By relying on an original data set covering 20 countries and 344 parliamentary elections, this article presents the first analysis of West European ‘genuinely new parties’ (GNPs) across time, countries and party families. We hypothesize that the parties differ not only in terms of their short- and long-term success but have a range of distinct development paths. Through a latent growth model, we provide a classification of GNPs in terms of their breakthrough and initial performance. According to the specific trajectory followed by new parties in the first five elections they contest, the model suggests five different classes of new parties in Western Europe: ‘explosive’, ‘meteoric’, ‘contender’, ‘flat’ and ‘flop’. The article discusses the implications of these findings also regarding the ability of the model to produce estimates and predictions about the future electoral performances of GNPs.

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Calibration of the SBUV version 8.6 ozone data product

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-5-5151-2012 ◽

2012 ◽

Vol 5 (4) ◽

pp. 5151-5203 ◽

Cited By ~ 9

Author(s):

M. T. DeLand ◽

S. L. Taylor ◽

L. K. Huang ◽

B. L. Fisher

Keyword(s):

Set Covering ◽

Retrieval Algorithm ◽

Data Set ◽

Data Product ◽

Ozone Data ◽

Ozone Trends ◽

Calibration Techniques ◽

Radiance Data

Abstract. This paper describes the calibration process for the Solar Backscatter Ultraviolet (SBUV) Version 8.6 (V8.6) ozone data product. Eight SBUV instruments have flown on NASA and NOAA satellites since 1970, and a continuous data record is available since November 1978. The accuracy of ozone trends determined from these data depends on the calibration and long-term characterization of each instrument. V8.6 calibration adjustments are determined at the radiance level, and do not rely on comparison of retrieved ozone products with other instruments. The primary SBUV instrument characterization is based on prelaunch laboratory tests and dedicated on-orbit calibration measurements. We supplement these results with "soft" calibration techniques using carefully chosen subsets of radiance data and information from the retrieval algorithm output to validate each instrument's calibration. The estimated long-term uncertainty in albedo is approximately ±0.8–1.2% (1σ) for most of the instruments. The overlap between these instruments and the Shuttle SBUV (SSBUV) data allows us to intercalibrate the SBUV instruments to produce a coherent V8.6 data set covering more than 32 yr. The estimated long-term uncertainty in albedo is less than 3% over this period.

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Calibration of the SBUV version 8.6 ozone data product

Atmospheric Measurement Techniques ◽

10.5194/amt-5-2951-2012 ◽

2012 ◽

Vol 5 (11) ◽

pp. 2951-2967 ◽

Cited By ~ 50

Author(s):

M. T. DeLand ◽

S. L. Taylor ◽

L. K. Huang ◽

B. L. Fisher

Keyword(s):

Set Covering ◽

Retrieval Algorithm ◽

Data Set ◽

Data Product ◽

Ozone Data ◽

Ozone Trends ◽

Calibration Techniques ◽

Radiance Data

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Annual Dynamics of Global Land Cover and its Long-term Changes from 1982 to 2015

10.5194/essd-2019-23 ◽

2019 ◽

Author(s):

Han Liu ◽

Peng Gong ◽

Jie Wang ◽

Nicholas Clinton ◽

Yuqi Bai ◽

...

Keyword(s):

Land Cover ◽

Environmental Change ◽

Global Environmental Change ◽

Global Scale ◽

Google Earth ◽

Data Set ◽

Global Land Cover ◽

Global Environmental ◽

Global Land

Abstract. Land cover (LC) is an important terrestrial variable and key information for understanding the interaction between human activities and global change. As the cause and result of global environmental change, land cover change (LCC) influences the global energy balance and biogeochemical cycles. Continuous and dynamic monitoring of global LC is urgently needed. Effective monitoring and comprehensive analysis of LCC at the global scale is rare. Using the latest version of GLASS (The Global Land Surface Satellite) CDRs (Climate Data Records) from 1982 to 2015, we built the first set of CDRs to record the annual dynamics of global land cover (GLASS-GLC) at 5 km resolution using the Google Earth Engine (GEE) platform. Compared to earlier global LC products, GLASS-GLC is characterized by high consistency, more detailed classes, and longer temporal coverage. The average overall accuracy is 85 %. We implemented a systematic uncertainty analysis at the global scale. In addition, we carried out a comprehensive spatiotemporal pattern analysis. Significant changes and patterns at various scales were found, including deforestation and agricultural land expansion in the tropics, afforestation and forest expansion in northern high latitudes, land degradation in Asian grassland and reclamation in northeast China, etc. A global quantitative analysis of human factors showed that the average human impact level in areas with significant LCC was about 25.49 %. The anthropogenic influence has a strong correlation with the noticeable Earth greening. Based on GLASS-GLC, we can conduct long-term LCC analysis, improve our understanding of global environmental change, and mitigate its negative impact. GLASS-GLC will be further applied in Earth system modeling in order to facilitate research on global carbon and water cycling, vegetation dynamics and climate change. The data set presented in this article is published in the Tagged Image File Format (TIFF) at https://doi.org/10.1594/PANGAEA.898096. The data set includes 34 TIFF files and one instruction doc file.

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Analysis of variability and long-term trends of sea surface temperature over the China Seas derived from a newly merged regional data set

Climate Research ◽

10.3354/cr01471 ◽

2017 ◽

Vol 73 (3) ◽

pp. 217-231 ◽

Cited By ~ 2

Author(s):

Y Li ◽

L Mu ◽

Y Liu ◽

G Wang ◽

D Zhang ◽

...

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Sea Surface ◽

China Seas ◽

Regional Data ◽

Data Set ◽

Long Term Trends ◽

The China Seas

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Is 3 years adequate for tracking completely occluded coiled aneurysms?

Journal of Neurosurgery ◽

10.3171/2019.5.jns183651 ◽

2020 ◽

Vol 133 (3) ◽

pp. 758-764

Author(s):

Eung Koo Yeon ◽

Young Dae Cho ◽

Dong Hyun Yoo ◽

Su Hwan Lee ◽

Hyun-Seung Kang ◽

...

Keyword(s):

De Novo ◽

Careful Monitoring ◽

Surveillance Period ◽

Radiological Data ◽

De Novo Aneurysm ◽

Low Probability ◽

Almost All ◽

Annual Risk

OBJECTIVEThe authors conducted a study to ascertain the long-term durability of coiled aneurysms completely occluded at 36 months’ follow-up given the potential for delayed recanalization.METHODSIn this retrospective review, the authors examined 299 patients with 339 aneurysms, all shown to be completely occluded at 36 months on follow-up images obtained between 2011 and 2013. Medical records and radiological data acquired during the extended monitoring period (mean 74.3 ± 22.5 months) were retrieved, and the authors analyzed the incidence of (including mean annual risk) and risk factors for delayed recanalization.RESULTSA total of 5 coiled aneurysms (1.5%) occluded completely at 36 months showed recanalization (0.46% per aneurysm-year) during the long-term surveillance period (1081.9 aneurysm-years), 2 surfacing within 60 months and 3 developing thereafter. Four showed minor recanalization, with only one instance of major recanalization. The latter involved the posterior communicating artery as an apparent de novo lesion, arising at the neck of a firmly coiled sac, and was unrelated to coil compaction or growth. Additional embolization was undertaken. In a multivariate analysis, a second embolization for a recurrent aneurysm (HR = 22.088, p = 0.003) independently correlated with delayed recanalization.CONCLUSIONSAlmost all coiled aneurysms (98.5%) showing complete occlusion at 36 months postembolization proved to be stable during extended observation. However, recurrent aneurysms were predisposed to delayed recanalization. Given the low probability yet seriousness of delayed recanalization and the possibility of de novo aneurysm formation, careful monitoring may be still considered in this setting but at less frequent intervals beyond 36 months.

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