General conclusions regarding the planetary–solar–terrestrial interaction

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Late Glacial deglaciation of the Zackenberg area NE Greenland

The Greenland Ice Sheet (GrIS) is a key component of the global climate system. However, our current understanding of the spatio-temporal oscillations and landscape transformation of the GrIS margins since the last glacial cycle is still incomplete. The objective of this work is to study the deglaciation of the Zackenberg Valley (74°N, 20°E), NE Greenland, and the origin of the derived landforms. Based on extensive fieldwork and high-detail geomorphological mapping we identified the different types of landforms, from which those of glacial and paraglacial origin were used to understand the processes driving regional environmental evolution. We applied cosmic-ray exposure (CRE) dating to 32 samples taken from erosive and depositional glacial landforms distributed across the valley. Geomorphological evidence shows that >800-m-thick Late Quaternary glacier filled the valleys and fjords and covered mountain summits. In subsequent phases, as ice thickness decreased, the glacier was limited to the interior of the valley, leaving several lateral moraines. The deglaciation of the Zackenberg Valley that started by ~13.7–12.5 ka also accelerated slope paraglacial processes. Many blocks from lateral moraines were remobilized and fell, reaching the valley floor where they covered the thinning glacier tongue; transforming it into a debris-covered glacier that subsequently melted gradually. By ca. 10.5 ka, the last remnants of glacial ice disappeared from the Zackenberg Valley floor, a chronology of deglaciation that is similar to that observed in other sites across NE Greenland. The results of this work must be considered in similar studies, reinforcing the need to support CRE ages of the different geomorphological phases with paleoclimatic data from other sedimentary records

Late Glacial deglaciation of the Zackenberg area, NE Greenland

The Greenland Ice Sheet (GrIS) is a key component of the global climate system. However, our current understanding of the spatio-temporal oscillations and landscape transformation of the GrIS margins since the last glacial cycle is still incomplete. The objective of this work is to study the deglaciation of the Zackenberg Valley (74°N, 20°E), NE Greenland, and the origin of the derived landforms. Based on extensive fieldwork and high-detail geomorphological mapping we identified the different types of landforms, from which those of glacial and paraglacial origin were used to understand the processes driving regional environmental evolution. We applied cosmic-ray exposure (CRE) dating to 32 samples taken from erosive and depositional glacial landforms distributed across the valley. Geomorphological evidence shows that >800-m-thick Late Quaternary glacier filled the valleys and fjords and covered mountain summits. In subsequent phases, as ice thickness decreased, the glacier was limited to the interior of the valley, leaving several lateral moraines. The deglaciation of the Zackenberg Valley that started by ~13.7–12.5 ka also accelerated slope paraglacial processes. Many blocks from lateral moraines were remobilized and fell, reaching the valley floor where they covered the thinning glacier tongue; transforming it into a debris-covered glacier that subsequently melted gradually. By ca. 10.5 ka, the last remnants of glacial ice disappeared from the Zackenberg Valley floor, a chronology of deglaciation that is similar to that observed in other sites across NE Greenland. The results of this work must be considered in similar studies, reinforcing the need to support CRE ages of the different geomorphological phases with paleoclimatic data from other sedimentary records

Basaltic Dyke with Specific Volcanogenic Structures and its geomorphic evolution: Unique Geoheritage of the Faroe Islands (North Atlantic Ocean)

Volcanic landforms resulting from Cenozoic volcanism represent the most peculiar features of global geodiversity and provide eminent narratives for geoeducation. Among them, however, relict volcanic forms and site-specific landforms in remote areas have received less attention. In this paper, we provide the first description of unique volcanogenic features (hereinafter referred to as pseudo-hieroglyphs) developed on a summit rock wall at the Sandfelli ridge near the village of Gjógv in the N Eysturoy Island (Faroe Islands). The geomorphic evolution of the ridge and rock wall during the Quaternary is described and detailed petrographic analyses of the volcanogenic features are provided. Based on observed petrographical features, we interpret the pseudo-hieroglyphs to probably represent unique examples of chaotic horizontal columnar jointing. Following the geomorphological and petrographic examination of the study site, we analyse current Faroese legislation aiming at nature conservation and use this case to discuss broader implications of geoheritage conservation and geotourism in distant regions.Vulkanická krajina vzniklá kenozoickým vulkanismem představuje nejpodivnější rysy globální geodiversity a poskytuje vynikající příběhy pro geovzdělávání. Méně pozornosti se však dostává reliktním vulkanickým formám a lokálním tvarům reliéfu v odlehlých oblastech. V tomto článku přinášíme první popis unikátních vulkanogenních tvarů (dále jen "pseudo-hieroglyfy"), které se vyvíjely na skalní stěně vrcholu na hřbetě Sandfelli u vesnice Gjógv v severní části ostrova Eysturoy (Faerské ostrovy). Je popsán geomorfologický vývoj hřbetu a skalní stěny během kvartéru a jsou uvedeny podrobné petrografické analýzy vulkanogenních vlastností. Na základě pozorovaných petrografických rysů interpretujeme pseudo-hieroglyfy, které pravděpodobně představují jedinečné příklady chaotické horizontální sloupcovité odlučnosti. Po geomorfologickém a petrografickém studiu zájmové lokality analyzujeme současnou faerskou legislativu zaměřenou na ochranu přírody a užíváme tohoto příkladu k diskusi širších důsledků zachování a geoturistiky geografického dědictví ve vzdálených regionech

A Farewell to Critical Junctures: Sorting Out Long-Run Causality of Income and Democracy

We consider the empirical relevance of two opposing hypotheses on the causality between income and democracy: The Democratic Transition claims that rising incomes cause a transition to democracy, whereas the Critical Junctures hypothesis denies this causal relation. Our empirical strategy is justified by Unified Growth Theory, which hypothesizes that the present international income differences have roots in the prehistoric past. Thus, we use prehistoric measures of biogeography as instruments for modern income levels, and find a large long-run causal effect of income on the degree of democracy. This result rejects the Critical Junctures hypothesis, which is an important part of the Primacy of Institutions view

Multispectral analysis of Northern Hemisphere temperature records over the last five millennia

Aiming to describe spatio-temporal climate variability on decadal-to-centennial time scales and longer, we analyzed a data set of 26 proxy records extending back 1,000–5,000 years; all records chosen were calibrated to yield temperatures. The seven irregularly sampled series in the data set were interpolated to a regular grid by optimized methods and then two advanced spectral methods—namely singular-spectrum analysis (SSA) and the continuous wavelet transform—were applied to individual series to separate significant oscillations from the high noise background. This univariate analysis identified several common periods across many of the 26 proxy records: a millennial trend, as well as oscillations of about 100 and 200 years, and a broad peak in the 40–70-year band. To study common NH oscillations, we then applied Multichannel SSA. Temperature variations on time scales longer than 600 years appear in our analysis as a dominant trend component, which shows climate features consistent with the Medieval Warm Period and the Little Ice Age. Statistically significant NH-wide peaks appear at 330, 250 and 110 years, as well as in a broad 50–80-year band. Strong variability centers in several bands are located around the North Atlantic basin and are in phase opposition between Greenland and Western Europe

Geomorphological applications of multi-model photogrammetry

The application of multi-model photogrammetry to steep cliff faces is described and examples given of the manipulation of the digitised data to produce three-dimensional terrain models, and by using other software models to estimate surface radiation balance.</jats:p