Ocean Cruising: A Sailing Subculture

1992 ◽  
Vol 40 (2) ◽  
pp. 319-343 ◽  
Author(s):  
Jim Macbeth

Just after dawn, an English couple in their 30's haul up their anchor and motor across the stillness of Suva harbour. The hurricane season is approaching and they are embarking on the 2–3 week trip to Bay of Islands New Zealand for the southern summer. Three months earlier, as their yacht lay aground on the fringing reef of uninhabited Suvarov atoll, they wondered if they'd ever reach New Zealand. But, with the help of other cruisers and lucky tides their steel 36 footer was clear and safe in under 24 hours. What was to be a one year trip around the north Atlantic was now happily way off course in the South Pacific and likely to remain so for some time. That is just a glimpse of one small aspect of ocean cruising, the subculture of interest here. However, throughout the paper the ethnography of cruising is developed further. A model is proposed to show how individuals come to share the subculture ideology and then to participate in the lifestyle. Subsequently, 1 will place ocean cruising in the context of subculture theory by expanding the ethnography and relating cruising to other subcultures.

2013 ◽  
Vol 26 (16) ◽  
pp. 6046-6066 ◽  
Author(s):  
Yalin Fan ◽  
Isaac M. Held ◽  
Shian-Jiann Lin ◽  
Xiaolan L. Wang

Abstract Surface wind (U10) and significant wave height (Hs) response to global warming are investigated using a coupled atmosphere–wave model by perturbing the sea surface temperatures (SSTs) with anomalies generated by the Working Group on Coupled Modeling (WGCM) phase 3 of the Coupled Model Intercomparison Project (CMIP3) coupled models that use the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4)/Special Report on Emissions Scenarios A1B (SRES A1B) scenario late in the twenty-first century. Several consistent changes were observed across all four realizations for the seasonal means: robust increase of U10 and Hs in the Southern Ocean for both the austral summer and winter due to the poleward shift of the jet stream; a dipole pattern of the U10 and Hs with increases in the northeast sector and decreases at the midlatitude during boreal winter in the North Atlantic due to the more frequent occurrence of the positive phases of the North Atlantic Oscillation (NAO); and strong decrease of U10 and Hs in the tropical western Pacific Ocean during austral summer, which might be caused by the joint effect of the weakening of the Walker circulation and the large hurricane frequency decrease in the South Pacific. Changes of the 99th percentile U10 and Hs are twice as strong as changes in the seasonal means, and the maximum changes are mainly dominated by the changes in hurricanes. Robust strong decreases of U10 and Hs in the South Pacific are obtained because of the large hurricane frequency decrease, while the results in the Northern Hemisphere basins differ among the models. An additional sensitivity experiment suggests that the qualitative response of U10 and Hs is not affected by using SST anomalies only and maintaining the radiative forcing unchanged (using 1980 values), as in this study.


Author(s):  
R. J. Adeney ◽  
G. M. Hughes

The oceanic sunfish Mola mola is occasionally found close to our shores, its normal habitat being the oceans throughout the world. It is replaced by Mola ramsayi only in the South Pacific (Fraser-Brunner, 1951). Specimens which are caught around the British Isles normally come from the North Atlantic as a result of being washed inshore when the warm westerly winds are blowing during the summer.


2021 ◽  
Author(s):  
Pedro Jiménez-Guerrero ◽  
Nuno Ratola

AbstractThe atmospheric concentration of persistent organic pollutants (and of polycyclic aromatic hydrocarbons, PAHs, in particular) is closely related to climate change and climatic fluctuations, which are likely to influence contaminant’s transport pathways and transfer processes. Predicting how climate variability alters PAHs concentrations in the atmosphere still poses an exceptional challenge. In this sense, the main objective of this contribution is to assess the relationship between the North Atlantic Oscillation (NAO) index and the mean concentration of benzo[a]pyrene (BaP, the most studied PAH congener) in a domain covering Europe, with an emphasis on the effect of regional-scale processes. A numerical simulation for a present climate period of 30 years was performed using a regional chemistry transport model with a 25 km spatial resolution (horizontal), higher than those commonly applied. The results show an important seasonal behaviour, with a remarkable spatial pattern of difference between the north and the south of the domain. In winter, higher BaP ground levels are found during the NAO+ phase for the Mediterranean basin, while the spatial pattern of this feature (higher BaP levels during NAO+ phases) moves northwards in summer. These results show deviations up to and sometimes over 100% in the BaP mean concentrations, but statistically significant signals (p<0.1) of lower changes (20–40% variations in the signal) are found for the north of the domain in winter and for the south in summer.


2009 ◽  
Vol 48 (9) ◽  
pp. 1902-1912 ◽  
Author(s):  
Josefina Moraes Arraut ◽  
Prakki Satyamurty

Abstract December–March climatologies of precipitation and vertically integrated water vapor transport were analyzed and compared to find the main paths by which moisture is fed to high-rainfall regions in the Southern Hemisphere in this season. The southern tropics (20°S–0°) exhibit high rainfall and receive ample moisture from the northern trades, except in the eastern Pacific and the Atlantic Oceans. This interhemispheric flow is particularly important for Amazonian rainfall, establishing the North Atlantic as the main source of moisture for the forest during its main rainy season. In the subtropics the rainfall distribution is very heterogeneous. The meridional average of precipitation between 35° and 25°S is well modulated by the meridional water vapor transport through the 25°S latitude circle, being greater where this transport is from the north and smaller where it is from the south. In South America, to the east of the Andes, the moisture that fuels precipitation between 20° and 30°S comes from both the tropical South and North Atlantic Oceans whereas between 30° and 40°S it comes mostly from the North Atlantic after passing over the Amazonian rain forest. The meridional transport (across 25°S) curve exhibits a double peak over South America and the adjacent Atlantic, which is closely reproduced in the mean rainfall curve. This corresponds to two local maxima in the two-dimensional field of meridional transport: the moisture corridor from Amazonia into the continental subtropics and the moisture flow coming from the southern tropical Atlantic into the subtropical portion of the South Atlantic convergence zone. These two narrow pathways of intense moisture flow could be suitably called “aerial rivers.” Their longitudinal positions are well defined. The yearly deviations from climatology for moisture flow and rainfall correlate well (0.75) for the continental peak but not for the oceanic peak (0.23). The structure of two maxima is produced by the effect of transients in the time scale of days.


2020 ◽  
Author(s):  
Kristofer Döös ◽  
Sara Berglund ◽  
Trevor Mcdougall ◽  
Sjoerd Groeskamp

&lt;p&gt;The North Atlantic Subtropical Gyre is shown to have a downward spiral flow beneath the mixed layer, where the water slowly gets denser, colder and fresher as it spins around the gyre. This path is traced with Lagrangian trajectories as they enter the Gyre in the Gulf Stream from the south until they exit through the North Atlantic Drift. The preliminary results indicate that these warm, saline waters from the south gradually becomes fresher, colder and denser due to mixing with waters originating from the North Atlantic. There are indications that there is also a diapycnal mixing, in the eastern part of the gyre due to mixing with the saline Mediterranean Waters, which would then be crucial for the Atlantic Meridional Overturning. The mixing in the rest of the gyre is dominated by isopycnic mixing, which transforms gradually the water into colder and fresher water as it spins down the gyre into the abyssal ocean before heading north.&lt;/p&gt;


2020 ◽  
Author(s):  
André Bahr ◽  
Stefanie Kaboth-Bahr ◽  
Andrea Jaeschke ◽  
Christiano Chiessi ◽  
Francisco Cruz ◽  
...  

&lt;p&gt;Eastern Brazil belongs to the ecologically most vulnerable regions on Earth due to its extreme intra- and inter-annual variability in precipitation amount. In order to constrain the driving forces behind this strong natural fluctuations we investigated a high-resolution sediment core taken off the Jequitinhonha river mouth in central E Brazil to reconstruct Holocene river run-off and moisture availability in the river&amp;#8217;s catchment. Modern day climate in the hinterland of the Jequitinhonha is influenced by the South American Summer Monsoon (SASM), in particular by the manifestation of the South Atlantic Convergence Zone (SACZ) during austral summer. Variations in the position and strength of the SACZ will have immediate impact on the moisture balance over the continent and hence influence sediment and water delivery. Our multi-proxy records, comprising XRF core-scanning, grain size, mineralogical (XRD), as well as organic biomarker analyses indicate abrupt centennial scale variations between dry and wet conditions throughout the past ~5 kyrs. Our results document a gradual weakening of the SASM over the past ~2,7 kyrs driven by changes in the intertropical heat distribution. This long-term trend is superposed by centennial to millennial-scale spatial shifts in moisture distribution that result from migrations of the SACZ. The combination of both processes caused increasingly pronounced aridity spells in eastern South America over the past 2 kyrs. As the spatial fluctuations were triggered by freshwater anomalies in the North Atlantic, we surmise that enhanced meltwater input into the North Atlantic due to future global warming might severely increase the risk for mega-droughts in tropical South America.&lt;/p&gt;


2005 ◽  
Vol 20 (4) ◽  
pp. 652-671 ◽  
Author(s):  
Yung Y. Chao ◽  
Jose-Henrique G. M. Alves ◽  
Hendrik L. Tolman

Abstract A new wind–wave prediction model, referred to as the North Atlantic hurricane (NAH) wave model, has been developed at the National Centers for Environmental Prediction (NCEP) to produce forecasts of hurricane-generated waves during the Atlantic hurricane season. A detailed description of this model and a comparison of its performance against the operational western North Atlantic (WNA) wave model during Hurricanes Isidore and Lili, in 2002, are presented. The NAH and WNA models are identical in their physics and numerics. The NAH model uses a wind field obtained by blending data from NCEP’s operational Global Forecast System (GFS) with those from a higher-resolution hurricane prediction model, whereas the WNA wave model uses winds provided exclusively by the GFS. Relative biases of the order of 10% in the prediction of maximum wave heights up to 48 h in advance, indicate that the use of higher-resolution winds in the NAH model provides a successful framework for predicting extreme sea states generated by a hurricane. Consequently, the NAH model has been made operational at NCEP for use during the Atlantic hurricane season.


2016 ◽  
Vol 144 (3) ◽  
pp. 877-896 ◽  
Author(s):  
Iam-Fei Pun ◽  
James F. Price ◽  
Steven R. Jayne

Abstract This paper describes a new model (method) called Satellite-derived North Atlantic Profiles (SNAP) that seeks to provide a high-resolution, near-real-time ocean thermal field to aid tropical cyclone (TC) forecasting. Using about 139 000 observed temperature profiles, a spatially dependent regression model is developed for the North Atlantic Ocean during hurricane season. A new step introduced in this work is that the daily mixed layer depth is derived from the output of a one-dimensional Price–Weller–Pinkel ocean mixed layer model with time-dependent surface forcing. The accuracy of SNAP is assessed by comparison to 19 076 independent Argo profiles from the hurricane seasons of 2011 and 2013. The rms differences of the SNAP-estimated isotherm depths are found to be 10–25 m for upper thermocline isotherms (29°–19°C), 35–55 m for middle isotherms (18°–7°C), and 60–100 m for lower isotherms (6°–4°C). The primary error sources include uncertainty of sea surface height anomaly (SSHA), high-frequency fluctuations of isotherm depths, salinity effects, and the barotropic component of SSHA. These account for roughly 29%, 25%, 19%, and 10% of the estimation error, respectively. The rms differences of TC-related ocean parameters, upper-ocean heat content, and averaged temperature of the upper 100 m, are ~10 kJ cm−2 and ~0.8°C, respectively, over the North Atlantic basin. These errors are typical also of the open ocean underlying the majority of TC tracks. Errors are somewhat larger over regions of greatest mesoscale variability (i.e., the Gulf Stream and the Loop Current within the Gulf of Mexico).


2020 ◽  
Author(s):  
Yeray Santana-Falcón ◽  
Pierre Brasseur ◽  
Jean Michel Brankart ◽  
Florent Garnier

&lt;p&gt;Satellite-derived surface chlorophyll data are daily assimilated into a three-dimensional 24 member ensemble configuration of an online-coupled NEMO-PISCES model for the North Atlantic ocean. A one-year multivariate assimilation experiment is performed to evaluate the impacts on analyses and forecast ensembles. Our results demonstrate that the integration of data improves surface analysis and forecast chlorophyll representation in a major part of the model domain, where the assimilated simulation outperforms the probabilistic skills of a non-assimilated analogous simulation. However, improvements are dependent on the reliability of the prior free ensemble. A regional diagnosis shows that surface chlorophyll is overestimated in the northern limit of the subtropical North Atlantic, where the prior ensemble spread does not cover the observation's variability. There, the system cannot deal with corrections that alter the equilibrium between the observed and unobserved state variables producing instabilities that propagate into the forecast. To alleviate these inconsistencies, a one-month sensitivity experiment in which the assimilation process is only applied to model fluctuations is performed. Results suggest the use of this methodology may decrease the effect of corrections on the correlations between state vectors. Overall, the experiments presented here evidence the need of refining the description of model's uncertainties according to the biogeochemical characteristics of each oceanic region.&lt;/p&gt;


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