Intraspecific variation in stem growth of western hemlock

1986 ◽  
Vol 16 (1) ◽  
pp. 149-151 ◽  
Author(s):  
D. F. W. Pollard ◽  
F. T. Portlock
Keyword(s):  
Sea Level ◽  
Intraspecific Variation ◽  
Test Site ◽  
Vancouver Island ◽  
Geographic Range ◽  
Stem Growth ◽  
Western Hemlock ◽  
Mean Sea Level ◽  
Provenance Variation

Fifteen coastal provenances of western hemlock Tsugaheterophylla (Raf.) Sarg. were tested on four sites on Vancouver Island, B.C. Provenance origins and test sites lay within roughly 2° of latitude and at 0–580 m above mean sea level. Mean heights of provenances 10 years after planting varied from roughly 74 to 121% of the plantation mean at each site; plantation means varied from 388 to 493 cm. No interaction between provenance and test site was detected and rankings of provenances remained quite constant from site to site. A large proportion of provenance variation could not be accounted for by descriptors of provenance origin. Results show that for the geographic range tested, faster growing provenances could be planted without constraints imposed by elevation and latitude.

scholarly journals Deterministic approach for multiple-source tsunami hazard assessment for Sines, Portugal

2015 ◽  
Vol 15 (11) ◽  
pp. 2557-2568 ◽  
Author(s):  
M. Wronna ◽  
R. Omira ◽  
M. A. Baptista
Keyword(s):  
Sea Level ◽  
Wave Height ◽  
Hazard Assessment ◽  
Test Site ◽  
Tsunami Hazard ◽  
Deterministic Approach ◽  
Flow Depth ◽  
Mean Sea Level ◽  
Tsunami Hazard Assessment ◽  
The Impact

Abstract. In this paper, we present a deterministic approach to tsunami hazard assessment for the city and harbour of Sines, Portugal, one of the test sites of project ASTARTE (Assessment, STrategy And Risk Reduction for Tsunamis in Europe). Sines has one of the most important deep-water ports, which has oil-bearing, petrochemical, liquid-bulk, coal, and container terminals. The port and its industrial infrastructures face the ocean southwest towards the main seismogenic sources. This work considers two different seismic zones: the Southwest Iberian Margin and the Gloria Fault. Within these two regions, we selected a total of six scenarios to assess the tsunami impact at the test site. The tsunami simulations are computed using NSWING, a Non-linear Shallow Water model wIth Nested Grids. In this study, the static effect of tides is analysed for three different tidal stages: MLLW (mean lower low water), MSL (mean sea level), and MHHW (mean higher high water). For each scenario, the tsunami hazard is described by maximum values of wave height, flow depth, drawback, maximum inundation area and run-up. Synthetic waveforms are computed at virtual tide gauges at specific locations outside and inside the harbour. The final results describe the impact at the Sines test site considering the single scenarios at mean sea level, the aggregate scenario, and the influence of the tide on the aggregate scenario. The results confirm the composite source of Horseshoe and Marques de Pombal faults as the worst-case scenario, with wave heights of over 10 m, which reach the coast approximately 22 min after the rupture. It dominates the aggregate scenario by about 60 % of the impact area at the test site, considering maximum wave height and maximum flow depth. The HSMPF scenario inundates a total area of 3.5 km2.

scholarly journals Scenario based approach for multiple source Tsunami Hazard assessment for Sines, Portugal

2015 ◽  
Vol 3 (8) ◽  
pp. 4663-4693
Author(s):  
M. Wronna ◽  
R. Omira ◽  
M. A. Baptista
Keyword(s):  
Sea Level ◽  
Hazard Assessment ◽  
Test Site ◽  
Tsunami Hazard ◽  
Container Terminals ◽  
Water Model ◽  
Worst Case ◽  
Mean Sea Level ◽  
Tsunami Hazard Assessment ◽  
The Impact

Abstract. In this paper, we present a scenario-based approach for tsunami hazard assessment for the city and harbour of Sines – Portugal, one of the test-sites of project ASTARTE. Sines holds one of the most important deep-water ports which contains oil-bearing, petrochemical, liquid bulk, coal and container terminals. The port and its industrial infrastructures are facing the ocean southwest towards the main seismogenic sources. This work considers two different seismic zones: the Southwest Iberian Margin and the Gloria Fault. Within these two regions, we selected a total of six scenarios to assess the tsunami impact at the test site. The tsunami simulations are computed using NSWING a Non-linear Shallow Water Model With Nested Grids. In this study, the static effect of tides is analysed for three different tidal stages MLLW (mean lower low water), MSL (mean sea level) and MHHW (mean higher high water). For each scenario, inundation is described by maximum values of wave height, flow depth, drawback, runup and inundation distance. Synthetic waveforms are computed at virtual tide gauges at specific locations outside and inside the harbour. The final results describe the impact at Sines test site considering the single scenarios at mean sea level, the aggregate scenario and the influence of the tide on the aggregate scenario. The results confirm the composite of Horseshoe and Marques Pombal fault as the worst case scenario. It governs the aggregate scenario with about 60 % and inundates an area of 3.5 km2.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

scholarly journals Tropical cyclone simulations over Bangladesh at convection permitting 4.4 km & 1.5 km resolution

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Hamish Steptoe ◽  
Nicholas Henry Savage ◽  
Saeed Sadri ◽  
Kate Salmon ◽  
Zubair Maalick ◽  
...  
Keyword(s):  
Wind Speed ◽  
Tropical Cyclone ◽  
Sea Level ◽  
Tropical Cyclones ◽  
Weather Forecasting ◽  
Sea Level Pressure ◽  
Mean Sea Level ◽  
Level Pressure ◽  
Medium Range ◽  
Gust Speed

AbstractHigh resolution simulations at 4.4 km and 1.5 km resolution have been performed for 12 historical tropical cyclones impacting Bangladesh. We use the European Centre for Medium-Range Weather Forecasting 5th generation Re-Analysis (ERA5) to provide a 9-member ensemble of initial and boundary conditions for the regional configuration of the Met Office Unified Model. The simulations are compared to the original ERA5 data and the International Best Track Archive for Climate Stewardship (IBTrACS) tropical cyclone database for wind speed, gust speed and mean sea-level pressure. The 4.4 km simulations show a typical increase in peak gust speed of 41 to 118 knots relative to ERA5, and a deepening of minimum mean sea-level pressure of up to −27 hPa, relative to ERA5 and IBTrACS data. The downscaled simulations compare more favourably with IBTrACS data than the ERA5 data suggesting tropical cyclone hazards in the ERA5 deterministic output may be underestimated. The dataset is freely available from 10.5281/zenodo.3600201.

scholarly journals Flooding Conditions at Aveiro Port (Portugal) within the Framework of Projected Climate Change

2021 ◽  
Vol 9 (6) ◽  
pp. 595
Author(s):  
Américo Soares Ribeiro ◽  
Carina Lurdes Lopes ◽  
Magda Catarina Sousa ◽  
Moncho Gomez-Gesteira ◽  
João Miguel Dias
Keyword(s):  
Climate Change ◽  
Sea Level ◽  
Climate Change Impacts ◽  
Storm Surges ◽  
Historical Period ◽  
Return Periods ◽  
Wave Regime ◽  
Mean Sea Level ◽  
Sea Levels ◽  
Far Future

Ports constitute a significant influence in the economic activity in coastal areas through operations and infrastructures to facilitate land and maritime transport of cargo. Ports are located in a multi-dimensional environment facing ocean and river hazards. Higher warming scenarios indicate Europe’s ports will be exposed to higher risk due to the increase in extreme sea levels (ESL), a combination of the mean sea level, tide, and storm surge. Located on the west Iberia Peninsula, the Aveiro Port is located in a coastal lagoon exposed to ocean and river flows, contributing to higher flood risk. This study aims to assess the flood extent for Aveiro Port for historical (1979–2005), near future (2026–2045), and far future (2081–2099) periods scenarios considering different return periods (10, 25, and 100-year) for the flood drivers, through numerical simulations of the ESL, wave regime, and riverine flows simultaneously. Spatial maps considering the flood extent and calculated area show that most of the port infrastructures' resilience to flooding is found under the historical period, with some marginal floods. Under climate change impacts, the port flood extent gradually increases for higher return periods, where most of the terminals are at high risk of being flooded for the far-future period, whose contribution is primarily due to mean sea-level rise and storm surges.

scholarly journals Approaching Sea-Level Rise (SLR) Change: Strengthening Local Responses to Sea-Level Rise and Coping with Climate Change in Northern Mozambique

2021 ◽  
Vol 9 (2) ◽  
pp. 205
Author(s):  
Serafino Afonso Rui Mucova ◽  
Ulisses Miranda Azeiteiro ◽  
Walter Leal Filho ◽  
Carina Lurdes Lopes ◽  
João Miguel Dias ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Sea Level Rise ◽  
Sea Level ◽  
North Coast ◽  
Coastal Regions ◽  
Mean Sea Level ◽  
Representative Concentration Pathways ◽  
Local Responses ◽  
Ipcc Report ◽  
Global Estimates

Mean sea-level is expected to rise significantly by 2100 in all scenarios, including those compatible with the objectives of the Paris Climate Agreement. Global sea level rise projections indicate devastating implications for populations, ecosystem services and biodiversity. The implications of the sea-level rise (SLR) on low-lying islands and coastal regions and communities are substantial and require deep-rooted coping measures. In the absence of adequate responses for coping, Mozambique is expected to record huge losses, with an impact on the economy and development in many sectors of its coastal regions mainly in northern Mozambique. This research aimed to perform projections on SLR in Mozambique, and to understand its role and implications on the north coast of the country. SLR was estimated through the analysis of model outputs that support the global estimates of the fifth IPCC report near the Mozambican coast, for each of the four representative concentration pathways (RCPs) scenarios. Regional coastline retreat and coastal erosion were estimated through the results of global sandy coastlines projections developed by Vousdoukas. Mean sea-level rise projections indicate that regional estimates for the Mozambican coast are relative higher than global estimates (~0.05 m) for all representative concentration pathways (RCPs). Yet, we highlight significant differences in sea-level rises of 0.5 m, 0.7 m or 1.0 m by 2100 compared to the global mean. It is expected that with the increase in the mean sea level in the northern part of the Mozambican coast, erosive effects will increase, as well as the retreat of the coastline until 2100. With this, the tourism sector, settlements, ecosystem services and local populations are expected to be significantly affected by 2050, with increased threats in 2100 (RCP4.5, RCP8.5). Local responses for coping are proposed and properly discussed for the RCP4.5 and RCP8.5 scenarios through 2100.

scholarly journals “Grey swan” storm surges pose a greater coastal flood hazard than climate change

2021 ◽  
Author(s):  
Kevin Horsburgh ◽  
Ivan D. Haigh ◽  
Jane Williams ◽  
Michela De Dominicis ◽  
Judith Wolf ◽  
...  
Keyword(s):  
Sea Level ◽  
Tide Gauge ◽  
Storm Surges ◽  
Natural Variability ◽  
Major Incident ◽  
Dynamical Response ◽  
Mean Sea Level ◽  
Coastal Flood ◽  
Extreme Storm ◽  
Observational Record

AbstractIn this paper, we show that over the next few decades, the natural variability of mid-latitude storm systems is likely to be a more important driver of coastal extreme sea levels than either mean sea level rise or climatically induced changes to storminess. Due to their episodic nature, the variability of local sea level response, and our short observational record, understanding the natural variability of storm surges is at least as important as understanding projected long-term mean sea level changes due to global warming. Using the December 2013 North Atlantic Storm Xaver as a baseline, we used a meteorological forecast modification tool to create “grey swan” events, whilst maintaining key physical properties of the storm system. Here we define “grey swan” to mean an event which is expected on the grounds of natural variability but is not within the observational record. For each of these synthesised storm events, we simulated storm tides and waves in the North Sea using hydrodynamic models that are routinely used in operational forecasting systems. The grey swan storms produced storm surges that were consistently higher than those experienced during the December 2013 event at all analysed tide gauge locations along the UK east coast. The additional storm surge elevations obtained in our simulations are comparable to high-end projected mean sea level rises for the year 2100 for the European coastline. Our results indicate strongly that mid-latitude storms, capable of generating more extreme storm surges and waves than ever observed, are likely due to natural variability. We confirmed previous observations that more extreme storm surges in semi-enclosed basins can be caused by slowing down the speed of movement of the storm, and we provide a novel explanation in terms of slower storm propagation allowing the dynamical response to approach equilibrium. We did not find any significant changes to maximum wave heights at the coast, with changes largely confined to deeper water. Many other regions of the world experience storm surges driven by mid-latitude weather systems. Our approach could therefore be adopted more widely to identify physically plausible, low probability, potentially catastrophic coastal flood events and to assist with major incident planning.

Mean Sea Level as a Reference for Geodetic Leveling

1974 ◽  
Vol 28 (5) ◽  
pp. 524-530 ◽  
Author(s):  
G. W. Lennon
Keyword(s):  
Sea Level ◽  
World Ocean ◽  
Equipotential Surface ◽  
Scientific Discipline ◽  
Mean Sea Level ◽  
Sea Levels ◽  
Coastal Sea ◽  
Long Time ◽  
Marine System

The use of mean sea level as a surface of reference that might provide an independent control for geodetic leveling has been a long term goal arising from the classical analogy between the geoid as an equipotential surface and the surface assumed by a hypothetical undisturbed world ocean. The problems associated with this aim are now known to be vast, and are associated with the dynamics of the marine system, notably its response to meteorological forces, to variations in density and to the effects of basic circulation patterns. In consequence the mean sea level surface varies rapidly in both time and space. This identifies in fact a distinctive scientific discipline, coastal geodesy, in which contributions are required by both geodesists and oceanographers. It has come to be recognized that the coastal zone is a hazardous environment for all observational techniques concerned. On the one hand, the difficulties of measurement of coastal sea levels have only recently been understood; on the other hand, precise leveling procedures are now known to be influenced by the attraction of marine tides and by crustal deformation of tidal loading. Much of the data available for study are therefore inadequate and, moreover, it should be noted that long-time series are required. It is now possible to lay plans for both geodetic and oceanographic procedures to remedy these deficiencies in the long-term interests of the study.

Mass and nutrient content of woody debris and forest floor in western red cedar and western hemlock forests on northern Vancouver Island

1993 ◽  
Vol 23 (6) ◽  
pp. 1052-1059 ◽  
Author(s):  
Rodney J. Keenan ◽  
Cindy E. Prescott ◽  
J.P. Hamish Kimmins
Keyword(s):  
Forest Floor ◽  
Forest Type ◽  
Woody Debris ◽  
Nutrient Content ◽  
Vancouver Island ◽  
Western Hemlock ◽  
N Availability ◽  
Red Cedar ◽  
The Mean ◽  
Western Red Cedar

Biomass and C, N, P, and K contents of woody debris and the forest floor were surveyed in adjacent stands of old-growth western red cedar (Thujaplicata Donn)–western hemlock (Tsugaheterophylla (Raf.) Sarg.) (CH type), and 85-year-old, windstorm-derived, second-growth western hemlock–amabilis fir (Abiesamabilis (Dougl.) Forbes) (HA type) at three sites on northern Vancouver Island. Carbon concentrations were relatively constant across all detrital categories (mean = 556.8 mg/g); concentrations of N and P generally increased, and K generally decreased, with increasing degree of decomposition. The mean mass of woody debris was 363 Mg/ha in the CH and 226 Mg/ha in the HA type. The mean forest floor mass was 280 Mg/ha in the CH and 211 Mg/ha in the HA stands. Approximately 60% of the forest floor mass in each forest type was decaying wood. Dead woody material above and within the forest floor represented a significant store of biomass and nutrients in both forest types, containing 82% of the aboveground detrital biomass, 51–59% of the N, and 58–61% of the detrital P. Forest floors in the CH and HA types contained similar total quantities of N, suggesting that the lower N availability in CH forests is not caused by greater immobilization in detritus. The large accumulation of forest floor and woody debris in this region is attributed to slow decomposition in the cool, wet climate, high rates of detrital input following windstorms, and the large size and decay resistance of western red cedar boles.

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