So what happens to those lost containers and what do Lego, running shoes and rubber duckies have to do with it? When you consider that an almost unimaginable total of million TEUs were shipped in , it is little surprising that statistically speaking at least some of them will go missing at some point during their journey. For a long time it was unclear just how many of these containers go overboard each year on average. An estimate of 10, containers annually is entirely plausible, which would mean the equivalent of 27 containers lost every day.
But it is definitely not quite as bad as that. Proper packing, stowage of the goods and securing of the containers and the correct reporting of weight are not just an art in and of themselves, but a real technical challenge. They are critical in ensuring the safety of the container ship, its crew and its cargo as well as of dockers and the environment. A number of critical factors remain even if the cargo has been properly stowed in the container, its weight taken into account during stacking and everything professionally secured.
Starting from a storm and rough seas, negligence, stack collapse all the way to catastrophic and rare events like a collision or running aground. The World Shipping Council commissioned a nine-year research study to come up with reliable figures for container loss. Between and , an average of containers were lost per year. This figure did not include catastrophic events, such as a ship sinking or running aground or shipwrecks examples include the Rena off of New Zealand in , the MOL Comfort in the Indian Ocean in and the El Faro off of Puerto Rico in But aside from catastrophes of this sort, sometimes all it takes is a storm at sea to send a container overboard.
The photographs of the television sets, dolls and sandals that washed up on Dutch beaches were seen around the world. If you think is a lot - the industry witnessed even higher losses recently: The Maersk Essen lost boxes in January in the Pacific, its sister ship, the Eindhoven, around boxes in February , and the ONE Apus a staggering 1, containers in December Essentially it is the shipping company that was hired to transport the goods that is responsible for them, and the companies are insured for precisely these cases.
Therefore also the client should be insured against these risks. A transport insurance policy covers not only damage or loss of merchandise up to the respective sum insured, but is also applicable in cases of "Havarie Grosse".
When the MS Zoe lost containers January , enthusiastic crowds flocked to the beaches to have a look at what had come ashore.
What is cargo deliberately thrown overboard from a sinking ship called? General Average Sacrifice? I think anything thrown from a ship is called jetsam, and anything floating from a sunken ship is called flotsam. More nautical terms. If the items thrown overboard do not float, but sink to the bottom, they are called jetsam.
If they sink, but are tied to a buoy for later recovery, they are ligan or lagan. McGruff Answer has 7 votes. McGruff Moderator 22 year member replies Answer has 7 votes.
Currently voted the best answer. However, the actual effectiveness of dispersants used at sea under the many different oil spill situations requires further understanding. Most studies on the effectiveness of dispersants used in the field indicate values of 20 to 70 percent, and under some special circumstances even higher, but most values are below 35 percent. Laboratory effectiveness testing of dispersants may also give variable values since several different standard test methods are used.
Studies are underway at the Warren Springs Laboratory in the United Kingdom to address this important issue. The effectiveness of dispersants will vary depending on many physical and chemical factors, such as oil properties, application method, droplet size, oil thickness, dosage rate or dispersant-to-oil ratio, wind and wave conditions, salinity, temperature, viscosity, pour point, and emulsification. Possible relationships between.
Daling, P. Brandvik, D. Characterization of crude oils for environmental purposes. Pourpoint and viscosity of Oseberg crude oil under selected sea states, showing potential for dispersibility.
Source: Daling, P. The use of demulsifiers in order to prevent formation of or reduce the amount of emulsion on the sea surface, followed by use of dispersants, is a relatively new response method under development in the United Kingdom. Application of demulsifiers during mechanical cleanup operations may also reduce the water content in the recovered emulsions and extend the time in operation in the field by decreasing storage requirements.
Oil spill cleanup based on mechanical equipment continues to be the most common response method for oil spills. Among mechanical recovery equipment, there exist a large number of booms and skimming principles. Booms for containment tend to be designed for operation in either calm, protected, or open ocean areas, and skimmers are often designed to operate within certain viscosity ranges. Their performance capabilities and effectiveness will therefore depend on the area of operation and the weathering properties of the oil, in particular the sea state, oil type, oil thickness, and degree of emulsification.
The key environmental constraints have been summarized, showing probable maxima for sustained performance ability for major open ocean containment and recovery systems currently in use: Waves, 2 to 4 feet significant wave height possibly up to 6 feet with certain equipment.
Assuming that equipment for spill response is available as identified in vessel response plans to deal with both small and large spills, the relationship of spill size to effectiveness of the response would probably be driven mainly by the increased complexity of large spills.
More oil on the sea surface also increases the probability that environmental conditions could become limiting to the response, increasing the time for weathering of the oil which is known to increase the difficulties of recovery operations, as described above. Quantification of the relationship, however, requires specific knowledge of spill response resources available, the time required for them to arrive on scene, characteristics of the spilled oil, and the environmental conditions of the spill.
There is a strong possibility in the case of large offshore spills that oil will impact shorelines even with best effort responses for control and recovery. If the discharge occurs nearshore most tanker accidents occur in the nearshore area , the oil spill is likely to reach the shoreline in only a short time. An evaluation of the significance of such contact has to take into consideration the geomorphology of the shoreline.
It is well understood 14 that high-energy shorelines are more easily washed clean by wave action, Also, there tends to be less retention of oil on rock faces and in unsorted beach material, although the viscosity of the impacting oil is an influential factor. Low-energy shorelines show a longer retention of beached oil, including sandy beaches and biologically sensitive areas such as salt marshes and mudflats.
These factors have to be considered in predicting the impact of spilled oil, but also in logistic planning for deployment of response resources. Response resources are finite and the overall effectiveness of a spill response may be enhanced by targeting efforts to those shoreline areas which might be most prone to impacts.
The toxicity of oil has a wide span among the different marine species, ranging from less than a part per million of oil to high concentrations. A consideration of toxicity to individual organisms has to take into account at least the following:.
Sensitivity of the individual organism of a species, which may vary with life stage. The sensitivity of a species or a population depends on its ecology. The zones of potential impact of oil spills are spatially limited to areas that contain oil, modified by the effect of dilution of toxic fractions of oil to a threshold where acute and chronic effects no longer occur.
Because oil weathers both physically and biologically, the spatial extent of an impact zone decreases with time, noted with all spills that have been investigated. The temporal change is of importance in determining the potential for exposure of a population—the population has to be present at a time when the oil is present in toxic quantities. For example, the effects of the Braer spill in January are likely to be less severe for seabirds because it occurred in midwinter when most of the birds were not present in traditional colony areas.
The high sea state at the time of the spill and the low persistence of the spilled oil will probably minimize residual effects on marine life when the seabirds and other species return in large numbers for the summer season to the Shetland Islands. By comparison, the Amoco Cadiz spill, which occurred in a biologically more vulnerable time, had a more severe effect on marine populations. It is beyond the scope of this paper to review these relationships in any degree of detail.
Such information forms the bulk of the oil spill literature and is presented in many summaries. Such sensitivities are. Malins, D. Volume I. Nature and Fate of Petroleum. New York: Academic Press. Volume II. Biological Effects. Neff, J. Engelhardt, F.
Petroleum Effects in the Arctic Environment. Geraci, J. Sea Mammals and Oil: Confronting the Risks. Review of Potentially Harmful Substances. Interest in this trophic level centers on two main aspects: a recognition that microbial systems constitute the bioenergetic basis of the marine ecosystem, and that microbes, in particular bacteria, can degrade contaminants such as hydrocarbons.
It has been determined that the composition of the microbial community changes with exposure to hydrocarbons, generally in favor of hydrocarbon degraders, the oleoclasts. Such changes may take days to months in marine waters and sediments, depending on water temperatures and the degree of any chronic pre-exposure to hydrocarbons. Biodegradation is most effective for lighter oils and in particular for the alkanes. High levels of oil appear to inhibit biodegradation due to a direct acute toxicity effect, which can be of relevance in considering differences of impact comparing small and large spills.
Oil pollution effects on these primary producers have been little studied, but it appears that growth and photosynthesis are inhibited by at least high oil concentrations. The significance of such an effect may, however, not be great since the effects of an oil discharge are local or regional in scale and would likely be buffered by adjacent phytoplankton populations once oil is no longer present at toxic levels.
If phytoplankton accumulate hydrocarbons, they may function as a vector for the biotransfer of these hydrocarbons to other trophic levels, especially to herbivorous zooplankton and filter-feeding benthos.
Again, the environmental effect is likely to be local or regional, and of limited duration. Although extensive lethality data are lacking, information available for zooplankton suggests LC50 values in the order of a fraction to a few parts per million. Such concentrations may be expected in the water column after a spill, with consequent debilitation of the zooplankton population in the local area. Again, exchanges among water masses and the plankton components are likely to buffer this effect with time.
Indeed, observations of zooplankton populations in spills have shown that while there is an effect of oil it is short-lived, and there are few changes in the biomass or standing stocks of zooplankton in adjacent open waters. The ability of zooplankton to take up hydrocarbons has been demonstrated and suggests a potential for biotransfer. However, long-term bioaccumulation and transfer to fish, for instance, is of low probability following an oil spill since the zooplankton are able to void accumulated hydrocarbons.
Tainting by biotransfer of higher trophic levels of the food chain is likely to be a temporary and localized phenomenon. The benthic invertebrate biota are an important component of the marine ecosystem, providing an energy base for fish, seabirds, and marine mammals. They respond to disturbances and represent an ideal effects monitoring system. This can occur after acute, post-spill exposure as well as after long-term chronic contamination in the parts-per-billion range.
In addition, benthic invertebrates are able to accumulate hydrocarbons to high levels from the surrounding medium, suggesting biotransfer as a possible concern, at least until such time as the accumulated hydrocarbons are voided.
Acute effects in benthic invertebrates tend to be tempered by their localized nature. Such a geographically limited effect might be significant if a local benthic population become reduced or contaminated in obligatory feeding areas for animals such as walrus or seabirds, eider ducks for instance. Wide-ranging chronic effects in nearshore benthos may be of concern following a large spill with a wide degree of lasting shoreline contamination. One area of benthic life that has received only scant attention is that of macroalgae, or seaweeds.
The seaweed community provides a habitat for many dependent species that form part of the nearshore food web. The presence of oil limits photosynthesis by biochemical inhibition and decreases primary production.
While the loss of macroalgae can be expected to change a nearshore benthic ecosystem for the short term, it can also be anticipated that recruitment through pelagic spores or larvae would eventually normalize a local or regional ecosystem effect.
Adult fish appear to be fairly resistant to oil exposure, in contrast to their sensitive egg and larval stages which are often planktonic. Fish tend to leave areas of high contamination and relatively little mortality is recorded.
Sublethal effects include impaired physiological salt and water balance, which might be crucial to anadromous fish such as salmon when they enter the freshwater phase of their spawning cycle.
A unique vulnerability for arctic fish may be at the ice edge, which is considered to be an important and productive habitat for many species. There is little evidence that standing stocks of fish have been much changed by oil spills. A more likely consequence is impact on harvest activities, either because the adult fish have left a contaminated area or because such fish have become or are perceived to be tainted through contact with oil.
The fate of seabirds has drawn great attention for several reasons. There is little doubt that birds exposed to oil fare poorly. The primary problem is a loss of thermal insulation, along with a decrease in buoyancy, increase in metabolism, and decreased reproductive success.
Certain species form special sensitive cases. The alcids, including murres, dovekies, and razorbills, are particularly susceptible, especially in northern areas where they tend to breed in a very few but large colonies, with a low reproductive turnover.
An oil spill in the vicinity of such a breeding area has a potential for serious impact on the population, and a prediction of impact would require close evaluation of the fate of the oil spill. Investigations of actual oil spill incidents have generally not been conclusive in identifying the toxicity of petroleum in seals or whales, even though mortality has been attributed to oil exposure at sea.
Only some of the species have demonstrated a clear sensitivity to petroleum in experimental studies. Recent studies in seals, sea otters, polar bears, and whales have helped to round out the limited information base on the subject. Although the cetaceans at least are able to detect oil on the sea surface, it remains controversial if marine mammals would avoid oil spills at sea. In some circumstances both whale and seal species have been observed to surface through oil slicks.
Contact with viscous oils can lead to long-term coating of the body surface of the furred marine mammals to result in thermoregulatory stress, or may interfere with the filtering capabilities of baleen in whales. A limited experimental data base suggests that seals, whales, sea otters and polar bears differ in degree of clinical toxicity damage following exposure to petroleum.
It is clear that both seals and whales are able to absorb hydrocarbons and will store the contaminants in blubber, as well as to a lesser degree in other body tissues. Tainting of harvested marine mammals is considered a potential problem.
Population-significant impact on marine mammals appears to be a potential only in definable circumstances, that is, restricted to localities that may seasonally host a large proportion of a population.
The high densities of white whales in estuaries and bays may be a case in point, as are traditional colony areas for walrus. Evaluations of impact have to be case specific. It is possible in only a general way to state that large spills have a greater potential for environmental impact than small-sized spills.
Since there appear to be significant exceptions to this statement, the situation should be analyzed in depth on the basis of global record for marine spills. An approach using the proposed ''Marine Oil Spill Scale'' might be useful. The results of both experimental data and information gathered from oil spills point out that a prediction of spill impact related to spill volume must take into consideration a wide range of variables. These include the characteristics of the spilled oil, physical environmental conditions, the effectiveness of oil containment and recovery measures, and the biological parameters of affected areas.
Rainer Engelhardt is vice president for research and development for the Marine Spill Response Corporation. He has an extensive background in oil spills and their effect on the environment.
He was formerly in executive management positions with the Canadian government, including the Canada Oil and Gas Lands Administration. There is a perception in the general population that oil spill models represent reality: turn one on and it tells what is going to happen with a spill and what is going to happen in the ocean.
That is not true. Each model has special strengths and weaknesses and it is not reasonable to consider any model outside the context in which it is intended to be used. My charge is to cover six aspects of trajectory modeling:. A model is a tool. You have something in mind when you apply it to a particular situation.
When considering a model to support a jettison decision, the particular type of incident must also be considered. For example, a grounding implies that a certain subset of ocean dynamics are involved.
Most importantly, it is nearshore, and models that might work very well in the open ocean won't work very well nearshore. Groundings have a tendency to degenerate and malinger. If the ship goes aground, there are a lot of feathers flying right away but it is very likely still to be a problem two weeks later. Thus for most groundings we should be looking at a model that has some capability to understand what is going on in a time scale of a week or a month, occasionally longer.
Yet when a grounding occurs, something needs to be done to stabilize or fix the situation quickly. The initial output, the initial recommendations, the initial look forward from a model, should be available very quickly. If a ship parks on a rock, bad things are going to start happening fast. The typical time scale is a tidal cycle. If a tanker sits on a rock and the tide drops it 10 feet on its end, it has a serious problem.
We need models that have high resolution, that can look forward in time, and that can get an answer out very quickly. That is the context in which we are going to try to evaluate and think about models. Virtually all oil spill models that are available have to say something about the current, because anything dropped in the ocean is carried away or drifts off with the flow.
This involves looking at oceanographic flow problems and hydrodynamics. In a nearshore regime, there is considerable complexity in this kind of a problem. One of the first things we need is models that realistically cover geophysical geometry.
Currents are averaged, for example, over 50 miles square or miles square. Those kinds of models won't help. We need to resolve complex shorelines and realistic bathymetry, and it is complicated.
In every model I know, shoreline and bathymetry factors have actually been taken out of the model and set in a separate submodel. Oceanographers run models that try to do that.
For example, a typical model that would resolve geometry would be based on a finite element scheme that can get realistic shapes down to some resolution. An alternative proposal would be to use a finite difference grid, or just a bunch of little cells.
In that case, the cells have to be quite small in order to resolve what you need to look at, and this would require much larger computer resources. Another characteristic of oil spills that every model has to deal with is that they start off small and if they are going to be a problem they eventually become big.
Models have to resolve multiple scales. You can't get fine resolution in one spot then carry it throughout because you will run out of computer space. This means that they consider the oil as a bunch of little pieces of oil and the flow as a larger scale field. You keep track of the oil by keeping track of all these particles and making some inference out of the information.
Models need to consider other physical processes besides moving along with the water. Most of them have a weathering component. Again, depending on the kind of oil involved, some fraction of the oil is going to disappear on its own. This means it will go somewhere else in the environment; it can evaporate, or it can disperse in such a way that you can't find it any more.
These factors are typically represented algorithmically and most models have such a component. They may vary in terms of quality, however. Some are quite coarse, but generally a sensitivity analysis would show that most of the models are adequate compared to human observational skill.
Most models also have algorithms or representations for beaching effects. When oil gets near a shoreline, it becomes a problem on the shore and you need to represent that computationally. The naive view is that when oil approaches a beach, it just drives up and parks on the beach.
That is not the case. Oil is probably more easily modeled like a tennis ball, you can get about three bounces out of it as it goes ashore. When oil approaches a shoreline, it has to stick to the shoreline. Typically, it will go ashore on a falling tide and an onshore wind. If it gets next to the beach, the currents alone won't take it ashore: it has got to be held against the beach by a wind and then the tide has to drop out from underneath it. Many times we have observed oil ashore when the winds are not onshore and the tide is dropping, but the oil doesn't stick.
When oil approaches a shoreline and the tide is rising, it won't stick. It just continues to fill up the beach face. For example, in the Huntington Beach spill, oil was on the shoreline and in the surf zone for a number of days, but the falling tide occurred in conjunction with a sea breeze reversal. Rubbish spread over alien sun Stone, almost identical, that is found on the beach Takes plane Tea in Boston Harbor, onc Things thrown overboard and washed up ashore Throwaways Travels fast with American that's thrown off ship What men threw overboard set out to clog nets.
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