Nothing to do with climate, but I thought you might find it interesting
The Hunt for October
Dr. Klaus L.E. Kaiser
Submarine warfare systems are in a class of their own. You may have seen the 1990 espionage thriller movie The Hunt for Red October. It portrays a late Cold War era encounter of various submarines. Suffice to say, a real suspense flick.
In WWI, German U-boats (submarines) were highly successful in sinking ships of foreign navies and merchant vessels. Initially the sudden loss of those vessels was unexplained but the then novel submarine warfare technology was quickly recognized and countered with other technology.
What has changed in 100 years?
Now, a century later, submarine technology is still a highly secretive “know-how-to” enterprise. Details of designs, material specs and limitations are highly guarded. In a surface vessel, a small oversight or material defect may hardly be noticed; however, in a submarine at depth it can mean the difference between survival and doom.
The most critical limitation is a sub’s depth of operation. Every 30 ft. (10 m) of depth adds a full atmosphere of pressure to the system. For submarines to be “invisible” or difficult to be detected from surface instruments, they need to be beneath the thermocline.
The thermocline is the layer at which water temperature and other water properties change over a relatively short distance of additional depth. As the Wikipedia image shows, the temperature change in the thermocline is from a balmy 24 C to a frigid 4 C.
Submarines that are below that thermocline are essentially undetectable to surface vessels. The thermocline acts like a mirror of the overlying water. However, for a sub to be able to dive under the thermocline (in the warm oceans at a depth around 500 m, i.e. 50 times atmospheric pressure), that’s no small feat either. Naturally, in the much colder polar water regions, the thermocline is much closer to the surface.
In contrast to WWI subs that needed to surface frequently to run diesel engines to recharge the batteries for silent underwater propulsion, nuclear-powered subs don’t have that requirement. Such modern subs can stay submerged for months at a time. That makes for a more sophisticated cat and mouse game these days.
Of course, not all subs are created equal. There are still many that use non-nuclear powered (typically diesel-powered) engines. What may surprise though is the number of subs that are listed by country at the website https://www.globalfirepower.com/navy-submarines.asp . The number one country (in terms of total number of subs) is – who would have guessed – North Korea. In close pursuit are the U.S., China, Russia, and coming in at the number 5 spot, yet another surprise, Iran.
Obviously, there are vast differences in size, range, armament, and diving capabilities between the various subs. However there is also another critical property that is important in that environment, namely the ability to move silently through the water. Older subs had a distinct pitch, caused by slightly uneven or unbalanced propeller flukes. In fact, during the Cold War period, many subs could be recognized just by their sound. Modern computer-designed and -machined propellers provide for a nearly quiet operation. That makes the subs’ detection and identification by sound patterns next to impossible.
Cat and Mouse Game
A very recent report by Sputnik News ( https://sputniknews.com/military/201708311056954661-norway-submarine-hunt/ ) says “After a series of agonizingly unsuccessful submarine hunts in Sweden, searching for Russian subs seems to have become one of the Nordics’ favorite past-times. Even now, an intense hunt for an alleged Russian submarine is taking place along Norway’s coast.”
Clearly then, the century-old cat-and-mouse submarine-game is still in full swing. Another “October” may be close by.
Dr. Klaus L.E. Kaiser is a professional scientist with a Ph.D. in chemistry from the Technical University, Munich, Germany. He has worked as a research scientist and project chief at Environment Canada‘s Canada Centre for Inland Waters for over 30 years and is currently Director of Research at TerraBase Inc. He is author of nearly 300 publications in scientific journals, government and agency reports, books, computer programs, trade magazines, and newspaper articles.
Dr. Kaiser has been president of the International Association for Great Lakes Research, a peer reviewer of numerous scientific papers for several journals, Editor-in-Chief of the Water Quality Research Journal of Canada for nearly a decade, and an adjunct professor. He has contributed to a variety of scientific projects and reports and has made many presentations at national and international conferences.
Dr. Kaiser is author of CONVENIENT MYTHS, the green revolution – perceptions, politics, and facts
Dr. Kaiser can be reached at: firstname.lastname@example.org