Large-Scale Synoptic Systems and Fog During the C-FOG Field Experiment

The goal of this work is to summarize synoptic meteorological conditions during the Coastal Fog (C-FOG) field project that took place onshore and offshore of the Avalon Peninsula, Newfoundland, from 25 August until 8 October 2018. Visibility was measured at three locations at the Ferryland supersite that are about 1 km from each other, and at two additional sites 66 and 76 km to the north. Supporting meteorological measurements included surface winds, air temperature, humidity, pressure, radiation, cloud-base height, and atmospheric thermodynamic profiles from radiosonde soundings. Statistics are presented for surface measurements during fog events including turbulence kinetic energy, net longwave radiation, visibility, and precipitation. Eleven fog events are observed at Ferryland. Each significant fog event is related to a large-scale cyclonic system. The longest fog event is due to interaction of a northern deep low and a tropical cyclone. Fog occurrence is also examined across Atlantic Canada by including Sable Island, Yarmouth, Halifax, and Sydney. It is concluded that at Ferryland, all significant fog events occur under a cyclonic system while at Sable Island all significant fog events occur under both cyclonic and anticyclonic systems. The fog-formation mechanism involves cloud lowering and stratus broadening or only stratus broadening for the cyclonic systems while for the anticyclonic systems it is stratus broadening or radiation. Although widely cited as the main cause of fog in Atlantic Canada, advection fog is not found to be the primary or sole fog type in the events examined.

Quantifying the diagenetic impact in the late Ediacaran and Early Palaeozoic of the Avalon Peninsula using illite “crystallinity”

The Avalon Peninsula, Newfoundland, Canada, defined as the type zone of Avalonia is believed to have been impacted by several orogenetic and deformation events since the Neoproterozoic. Previous studies determined the lowest degree of metamorphism reached in the successions was of the prehnite-pumpellyite or greenschist facies. We sampled and measured thirteen clastic sedimentary sections ranging from the late Ediacaran to the Early Ordovician and analysed the illite “crystallinity” of 331 samples using the Kübler index. Our results show diagenetic zones occur related to lithology, age and burial depth, respectively, and regional setting. Samples adjacent to the fault zones bounding the Holyrood Horst experienced among the highest degree of metamorphism (anchizone) in the study area. The lowest degree of thermal alteration occurs in the high stratigraphic sections at the centre of the horst structure where shallow diagenetic conditions are preserved. Fault zones, most probably active during the Acadian Orogeny, may have served as potential paths for hot fluids in bounding areas of the horst, whereas the centre of the horst remained almost unaffected by any metamorphic overprint. The thermal impact decreases from the Bonavista Peninsula to the study area from greenschist facies to anchizonal and diagenetic. The study area experienced lower metamorphic conditions than major regions of Avalonia south of the study area on the mainland of New Brunswick and Maine and eastwards in Europe. The thermal impact is in part consistent with a few other areas of Avalonia, such as the Mira terrane and the Antigonish Highlands in Nova Scotia.

Modeling Tile Drainage Outflow in Thin Agricultural Soils with Impermeable under Layer in Newfoundland and Labrador, Canada

Subsurface tile drainage installation helps to maintain water table levels and to meet adequate crop moisture requirements. Artificial subsurface drainage continues to be a common practice in Newfoundland and Labrador (NL) and elsewhere around the world. The main objective of this study was to evaluate the performance of DRAINMOD in simulating water table depth (WTD) and water outflow from tile drained agricultural fields. This site on the Avalon Peninsula of Eastern Newfoundland has a rolling landscape with predominantly Podzolic soils. The tile drainage was installed at 1.0 m deep and spaced 12 m apart. Drainage outflows (two per plot) from twelve experimental plots (32 m x 60 m each) were monitored for two years. The simulated WTD ranged from 140 cm to 160 cm during rainfall season. The performance of the model was evaluated by the Index of agreement (IOA). It was 0.600 in 2017 and 0.559 in 2018. The result was considered to have acceptable accuracy, which can help to design or evaluate subsurface drainage systems in NL, Canada. However, further evaluation including additional sites are necessary to ensure optimum drainage design parameters for the major agricultural soils.

A Eulerian Explosive Cyclogenesis climatology from the ERA5 reanalysis, 1979-2018

<p>Using the criterion of one Bergeron (24 hPa change over 24 h at 60°), we present the creation of a Eulerian explosive cyclogenesis climatology using hourly-temporal resolution data from the European Centre for Medium Range Weather Forecasting’s ERA5 reanalysis (1979-2018). This approach differs to the typically used Lagrangian methodologies adopted by many studies. The climatology created by this approach results in similar patterns to previous studies.</p><p>Assessments on the dataset are undertaken to analyse the influence of seasonality, teleconnections, climate change and individual events (the method picks up tropical cyclones as well as mid-latitude storms). The location experiencing the most consistent explosive cyclongenesis conditions (15% of the time during the Northern Hemisphere winter) is to the east of the Avalon Peninsula, Newfoundland. The preferred location of explosive cyclogenesis is shown to change in relation to patterns such as the El Niño Southern Oscillation and North Atlantic Oscillation. Potential applications of the dataset are suggested.</p><p>                                                </p>

Post-glacial recolonization of insular Newfoundland across the Strait of Belle Isle gave rise to an endemic subspecies of woodland caribou, Rangifer tarandus terranovae (Bangs, 1896): evidence from mtDNA haplotypes

Post-glacial origins of woodland caribou (Rangifer tarandus subsp.) on the island of Newfoundland and their relationship to mainland populations have been uncertain. Sequence analysis of 2223 bp of the mitochondrial DNA control region and cytochrome b gene from 233 Newfoundland caribou identified 32 haplotypes in four major clades. Comparison with other Nearctic caribou confirms a closer affinity of the basal Clade A with animals from the mainland, and as an outgroup to Clades B, C, and D that are endemic to the island. This indicates re-entry of caribou to post-glacial Newfoundland across the Strait of Belle Isle from Labrador, rather than from southern coastal refugia. Newfoundland caribou are a distinct subspecies, Rangifer tarandus terranovae (Bangs, 1896). Hierarchical AMOVA shows significant clinal differentiation of the major clades from northwest to southeast across the island. The isolated Avalon Peninsula population in the extreme southeast is genetically depauperate. Founder effects are evident in herds introduced to previously unoccupied areas by wildlife managers over the past 40–50 years. Reindeer introduced in the early 20th century have not contributed to mtDNA diversity in Newfoundland caribou.

Neoproterozoic Oxygen and The Rise of Animals

This chapter considers the significance of the Ediacaran Fauna. Until the late 1980s, the Ediacaran Fauna were usually thought to represent ancient, primitive animal forms. Debate was sparked when leading paleontologist Dolf Seilacher from Tubingen, Germany, reinterpreted these fossils as something completely different. He argued that, instead of animals, they were long-extinct varieties of living organisms, a result of failed lineages with no successors. The rocks on the Avalon Peninsula of southeastern Newfoundland house the oldest known representatives of the Ediacaran Fauna. These so-called rangeomorphs date back to 575 million ago and appear relatively soon after the end of the Gaskiers glaciation some 580 million years ago. Evidence suggests that Ediacaran Fauna of the Avalon Peninsula emerged into an ocean undergoing oxygenation.

Distributional Status of an Introduced Land Snail Discus rotundatus (Rotund Disc, Mollusca: Discidae) in Canada

First collected in North America in 1937 on the Avalon Peninsula of the Island of Newfoundland, the introduced, primarily European land snail, Discus rotundatus, has now been recorded from the Island of Newfoundland, Nova Scotia, New Brunswick, Quebec, Ontario, and British Columbia. We review all known records from Canada, demonstrate that D. rotundatus is more widespread than was previously recognized on the Island of Newfoundland, and report the first record from New Brunswick.