 2015-09-23 21:49:00
|
Post #26
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中心SAN JUAN ... |
 markka123456
|
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中心SAN JUAN ... 杨版的潮汐窗口期和风窗口期理论，需要在实际中实践，才能运用自如。 |
|
---------------------------------------- |
|
|
2015-09-23 22:21:34
|
Post #27
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
kurtyang04
|
markka123456 wrote: 杨版的潮汐窗口期和风窗口期理论，需要在实际中实践，才能运用自如。 潮汐窗口期可以在行程规划中预先考虑影响，而风窗口期的影响择需要结合风力预报和实际的情况综合判断，这就需要极强的现场综合判断能力。 是这样, 设计往往和实际有偏差, 在理论和规划指导下, 现场判断能力才能把有利因素实现,避开实际误差带来的危险. |
|
2016-06-10 05:25:13
|
Post #28
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
[url]https://www.youtube.com/watch?v=FezsFM5AEsM&feature=player_embedded"[/url] ————————— 海洋最恐怖之一的恶性大回水， 翻墙看奇观（有人落水），救援机动船翻船 这个正是DEEP TROUBLE书里，这个帖子前面阐述事故的发生地录像 |
|
2016-06-10 06:10:43
|
Post #29
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
一个普通爱好者（海洋不是特别强）朋友评论头页事： This chapter involves a rescue of three paddlers out of a group of five. While, luckily, this group had an experienced guide who was carrying a VHF radio, this whole incident could have been avoided had the group stayed out of wind and the tide rip that eventually caused two of the paddlers in a tandem to capsize. The guide did not capsize, but intentionally exited his kayak to swim over and assist the two paddlers in the tandem whom he feared were having trouble exiting the upturned kayak. If you are unfamiliar with tide rips, watch the YouTube video above showing swimmers in a tide rip in Deception Pass which is not too far from Rosario Strait where the story in Chapter 18 takes place. Strong winds also played a factor in causing this capsize. For a review of the importance of "paddling in the lee", you can re-read the side-bar article in Chapter 17, and my previous blog post, "More Thoughts on the Ferry Rescue in Chapter 17". Here in the Great Lakes, we are happy not to have to worry about the dangers of these strong currents caused by tidal movements of the water. However, we are quite familiar with the dangers of strong winds. If you have plans to paddle in the ocean though, especially in areas like the San Juan Islands that have strong tidal currents that develop among the islands, it is really important that you understand how these tide rips develop, where they develop, and learn to avoid them if you don't have the skills to paddle through them. |
|
2016-06-10 06:14:20
|
Post #30
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
人家没有太多大海经验的人都读此书，所以理解这个在大海里一个难以征服的现象，避开就是唯一的解决办法。 要避开如何形成，在哪里形成，什么时候形成，才能达到主动避开的结果。 |
|
2016-06-10 06:27:05
|
Post #31
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
关于离岸风： 这里有一篇非常好文章，我慢慢来翻译解释： https://nswskc.wordpress.com/1996/03/24/offshore-winds-26/ Offshore Winds [26] Posted on March 24, 1996 by smeyn Those Deceptive But ‘orrible Offshore Winds By Paul Caffyn Wind is the curse of sea kayakers. It generates the bulk of problems that arise, choppy seas, capsizes, wind chill, weather tide effects, surf and so on. There is however an exception; a following breeze, or one quartering from astern, can be a real boon in aiding progress through surfing rides. A breeze on the beam requires continuous corrections for drift and more concentration on balancing the boat. A breeze on the nose, or quartering from the bow, generates soul destroying, tiring, very wet, slogs. The most deceptive and horrible wind blows offshore. Deceptive in that conditions may appear flat calm against shore with a light breeze wafting offshore, but with increasing distance offshore wind strength increases dramatically. Cliffed coastlines or those with marked topographic relief such as dune ridges, or swathes of forest, are particularly deceptive. Lurking sea kayaker traps are wherever those continuous cliffs or dune ridges are broken by gorges, fiords, steep sided valleys and narrow entrance bays. Recently I received a swag of E mail messages from Sandy Ferguson relating to a party of New South Wales sea kayakers who were subjected to the deceptive but ‘orrible offshore winds at Jervis Bay, south of Sydney. I can sympathise with the N.S.W. paddlers’ predicament, for yours truly was caught during the Australian trip a long way offshore immediately south of Jervis Bay by a sudden, dramatic wind shift, that left me with such a struggle against an offshore wind that I felt like throwing in the towel and abandoning the trip. Limping into the lee of St. Georges Head I coined the phrase, ‘Wind was definitely the curse of the canoeing class.’ An article on offshore winds is pertinent, particularly after the article by John RamweII in the last magazine on the Lyme Bay tragedy. Wind Strength Above an altitude of 500 to 600m, wind has an unobstructed flow over the sea while below that height, there is increasing frictional or drag effect between the air and the surface over which the wind is blowing, resulting in a diminishing of wind speed as the ground or sea is approached. The amount of wind strength reduction depends on the nature of the surface; over forested hilly terrain the air flow will be less than that over open sea because of greater frictional drag. Approximate values have been determined for frictional drag: over open sea a wind 500m above the sea reduces by about 33% at sea level, while over land the reduction is 66%. Thus a 30 knot wind at 500m will produce a 20 knot wind over the sea and 10 knots over land. There is where the ‘deceptive’ description for offshore wind applies, for a factor of 50% can be applied to wind when it blows from land out to sea. A gentle breeze of 6 knots inland becomes a moderate wind of 12 knots offshore and a 15 knot wind inland becomes a near gale of 30 knots at sea. The height and nature of a coastline govern the zone width of calm, sheltered water in offshore wind conditions: a. a long beach with a low sand dune ridge providing minimum relief, dictates a minimum width with the offshore wind felt at the water’s edge. b. a continuous line of vertical cliffs will provide a maximum width of calm, sheltered water, naturally depending on the height of the cliffs which govern where the offshore wind hits the sea The obvious problem with offshore winds is being blown offshore. Where there is no off-lying shelter, such as a reef or island, and the next continent is thousands of miles away, the chances of survival without a radio or batphone are zilch. I maintain that once a wind rises over 30 knots, paddling progress into the wind grinds to a halt. Any misadventure such as a dropped paddle or capsize, both occurred with two paddlers off lervis Bay, resulting in instant seawards drift and a greater distance to reach shore after recovering from the misadventure. By way of example to those who have yet to experience such conditions, I struck diabolical offshore conditions during my first day in the Bering Sea, on the northern side of the Alaska Peninsula with a gale force wind blowing offshore over a low dune ridge and flat tundra inland. The sea was flat calm, a low surge against a gravel beach, wind ripples close inshore and an increasing density of whitecaps with distance out from the beach. Deceptively good paddling conditions, but bear in mind the 50% increase in wind strength from land to sea, and conditions more than 10m offshore were well beyond my limit to reach the beach. I spent many hours crabbing my way along the beach, the kayak at a 45 degree angle to the line of the beach to check offshore wind drift, the bow rising and falling against the beach with each surge. I was fully aware of the risk, realising the next stop offshore was the ice pack and unbearable polar bear country. At the base of a long continuous line of cliffs, excellent shelter is afforded in strong offshore winds. Steep hillsides close to the coast, continuous dune Adges and tall forest also offer shelter dose to a beach. But wherever that continuous line of shelter is broken abruptly, for instance by a narrow fiord, narrow bay or harbour entrance, gorge, river or stream valley, the offshore wind is funnelled through that break with unbridled force, causing williwaws and violent gusts or bullets of wind. And it is the violence of the turbulence that can cause the loss of a paddle or a capsize. Manye sheltered bays and harbours have narrow entrances which open back into broad areas of calm water. Jervis Bay in New South Wales is a classic sheltered bay, which has a narrow entrance with tall cliffed headlands on both sides and we have many such examples in New Zealand. Offshore winds funnel through such narrow entrances with double or triple the wind strength of that inland. Also where a continuous line of cliffs of steep coastline is broken by a headland or cape projecting seawards, increasing wind strength must be expected often accompanied by williwaws and strong gusts or bullets of wind. What to Look For An increasing density of whitecaps with progressive distance offshore are the best indicator of strong offshore winds, along with spray fanning seawards off breaking wave crests. White spray dancing over the water, indicates a wind funnel with bullet like gusts of wind lifting spray off the sea. Suggestions for Remedial Action If an offshore wind is blowing at the launch site, be prepared to abort or shorten the length of the trip. if caught in a sudden or gradual change to an offshore wind, turn tail immediately and run for the beach or nearest shelter. Sea conditions will deteriorate as the wind continues to blow offshore. When faced by a wind violently funnelling out of a harbour or fiord etc., either return to the launch site or attempt to land and wait until the wind strength abates. Patience is the order of the day. If there is any doubt, it is better to wait. When caught on an exposed coast by a change to offshore wind conditions, hug the coast intimately, even if this adds considerably to the distance paddled for example by paddling around the curve of a bay. Do not make straight line crossings of the narrow entrances to bays, fiords or harbours. Paddle upwind into the feature far enough before kicking out on the crossing. This is to combat ensuing wind and chop drift during the crossing and ensure reaching the far side safely. Weather Forecasts Marine forecasts relate to powered vessels and not paddler powered kayaks. Offshore winds commonly knock down the sea state, diminishing swell size and generating reasonable fishing conditions for powered vessels. Listen to the marine forecast and if the stated wind direction is offshore in your area, be extra wary before commencing a paddle. We know forecasts are not always accurate, hence a final decision to paddle or not must be made at the launch site. Points to Remember Offshore wind conditions are deceptive, with calm water and light breezes against the beach. Always look for whitecaps offshore. Wind strength increases by 50% when passing from land to open sea. Narrow topographic features funnel offshore winds, with dramatic turbulenc |
|
2016-06-27 23:16:57
|
Post #32
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
"kurt2: Body of missing kayaker found [url]http://www.wjhg.com/wecp/content/news/Walton-County-officials-searching-for-missing-kayaker--384377791.html[/url]" ————————— "kurt2: Body of missing kayaker found 这个事故发生在亚热带,失温可能性有，但这次22-25度水温，起的作用可能不超过20%， 被浪旋翻然后回不了陆地，估计是主要因素，陆地陆地！！ 回头是岸，对离岸距离的敏感是海洋皮划艇另一极其重要安全因素，多在公开水域离岸远多呆一分钟时间就意味多一分危险（当然和天气风向潮水有关）。 在美国，休闲皮划艇，浆板，钓鱼船带动户外这俩年，最大最可观发展，同时死亡事故，也跟着攀升。" ————————— |
|
2016-06-27 23:18:36
|
Post #33
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
Florida Fish and Wildlife Conservation Commission officials have found and recovered the body of a missing kayaker. According to the Walton County Sheriff's office, FWC officers found the body of Christopher Hinton in the middle of the bay, due south of the Lagrange Bayou. Officials on the water were able to confirm the clothing on the body matched the description of of those Hinton was wearing when he disappeared while kayaking on the bay Friday afternoon. In a statement, Walton County sheriff's officials thanked the other agencies for their help in the search, and expressed their condolences to Hinton's family. They also thanked the community for their support during the search. --- UPDATE 6/25/15 2:00 p.m. Officials believe they've located the kayak of the missing kayaker Saturday afternoon. According to Walton County Sheriff's Officials and Fish and Wildlife, just before 2 o'clock they found the lime green kayak they believe to be the one Christopher Hinton was using when he went missing. Officials found it on the northwest side of the bay. They also found a paddle. |
|
2016-06-28 02:58:15
|
Post #34
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
http://www.pressherald.com/2016/06/23/kayakers-who-perished-were-part-of-tour-group/&t_u=http://www.pressherald.com/2016/06/23/kayakers-who-perished-were-part-of-tour-group/&t_e=Sea kayaking guide and one of his clients die during Down East excursion&t_d=Sea kayaking guide and one of his clients die during Down East excursion - The Portland Press Herald / Maine Sunday telegram&t_t=Sea kayaking guide and one of his clients die during Down East excursion&s_o=default&l=#][/url] William Linnell Zed • 3 days ago Number one on the list, "sea worthy boat", should include some qualification. A kayak is not a particularly sea worthy vessel. Kayaks typically are only 25 inches wide or less. They were design to go fast on relatively flat water. Because they were developed and used by natives, people might assume they are more seaworthy than they really are. They give up a huge amount of initial stability in order to be paddled by someone holding a paddle close to the body. In contrast, a dory has wider, flared sides which make it inherently a much safer boat. Kayaks are fast and fun, but need to be used very close to shore with rare exceptions.Seems like there are at least three or four kayaker deaths per year in Maine. And it's always the same situation, with the kayak swamped and paddler in the water. The relatively low cost, easy car-topping transport popularity, the connection to native origins grossly overestimating their seaworthiness, and underestimating the likelihood of being immersed for a period of time, all combine to make these craft more potentially dangerous than people realize. |
|
2016-06-28 03:11:20
|
Post #35
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
|
kurtyang04
|
这种意见说，海洋舟过于太窄，在安全上有天生的缺陷，为了达到一种快速，很好玩，和便于浆法，牺牲了第一稳定性和安全系数。所以翻是必然的（指长期的活动），由于翻一次或几次的可能性（长期划行）很大，海洋舟必须尽量靠近岸边活动（更适合海岸线划行），以及完全理解浸在冷水长时间的后果。 缅因每年海洋都葬送几条命，规律基本都一样：皮划艇灌满水，而人一直在水里（失温的后果）。 这个意见告诉人，理所当然认为自己不翻就是不尊重海洋皮划艇特性，温度和离岸距离，是海洋舟安全因素里最重要之二， 除了风和洋流 |
|
2020-01-03 01:43:57
|
Post #36
Re: 海洋洋流（离岸流），离岸风- 世界海洋事故中 ... |
ok100
|
珍贵的分享，太感谢了。 |
邀请xuliang1215参加此活动
分享
