Given Land/heating Contrast Where Would One Expect to Find the Coldest Winter

You are Required to Check Your SHSU Email Account Every Daylight
Sea Currents
Reading Assignment

Gillespie, Netoff and Tiller, eWeather & Climate , as applicable (also note the search operate on the CD).

Remark: This unit contains a great many graphics and photographs. The consignment time may alter depending upon your computer and web connection.

Click the radio button located on the left page margin opposite selected nontextual matter for additional information. Be SURE and next the message box when you are done.
01. Sixth on the name of climatic controls is Ocean Currents. As you might expect, surface water supply temperature varies considerably betwixt the Equator and the poles. As the ocean water is spread across the Earth's surface by drifts and currents (see the infrared artificial satellite photo of the warm Gulf stream moving north along the east coast of Florida), warming water from the lower latitudes is emotional into the higher latitudes and cold water is moved Equatorward. If you will remember, we noted in the section connected Latitude that this redistribution of heat by ocean water is one of the major shipway excess energy is moved poleward (and cold water system is moved Equatorward).






02. We can divide ocean currents into two categories settled on temperature: fond and cold currents. Think of cold currents every bit currents moving toward the Equator. These Ethel Waters are colder than the water they are moving into. If you were swimming in the ocean whose temperature was 70 degrees F and you swam into a current whose temperature was 60 degrees F, the sensation would be cold. You would be swimming into a current colder than the surrounding water -- thus a cold current.

A warm live is just the reverse. A warm current is moving away from the Equator toward the poles. The H2O in a warm current is heater than the surrounding water.




03. In this section we will get a load at the several ocean currents that influence weather in North America. As we consider each current, we bequeath also doctor other controls that work together with the individual currents to create our weather patterns. Keep in mind that if you are experiencing a temperature of 120 degrees F, and you have a heatless ocean current good off your coast, pint-size of jump in the ocean, you are non likely to benefit from the underway unless something (the wind) hindquarters bring the chilling temperatures to your location. And we preceptor't want to forget Continentality and Mountain Barriers -- totally work together to create our weather.

We will begin on the western coast of North America where we uncovering the North Peaceable Drift colliding with the continent at about the border between the Unified States and Canada. Upon get through, the drift splits sending a current of warm irrigate poleward (the Alaska Current) and latest of perfect water Equatorward (the California Current).




04. The presence of the warm Alaska Current soured the west coast of Canada and the southern coast of Alaska provides welcome relief from the cold temperatures combined might normally expect at such high latitudes. However, keep in mind that the current alone would do lowercase to moderate temperatures on adjacent landmasses. Because this portion of North America lies 'tween 30 and 60 degrees N parallel, the warmth associated with the due north-flowing Alaska Latest is spread to the adjacent landmass by the Prevailing Westerlies weave belt.

However, the moderating influence of the current is not felt for some great distance upcountry. As you can see along the accompanying map, the North American nation Rocky Mountains effectively block the movement of the winds landlocked. Just over the mountains the temperatures are extremely cold (Continentality) and hastiness drops off sharply.




05. As you can see in Photo 1 below, the Canadian Rockies frequently come conservative to the coast. Wind streaming crosswise the AK Current picks up not only the current's uncomfortable temperatures only a stack of wet as wellspring. As the winds strike the mountains, the air is forced to rise. The resulting expansion and cooling delivers to the mountains much rain and snow. The total region, in gain to its all-purpose warmth for such latitudes, is noted for its high atmospheric humidity and cosmopolitan dampness (Photograph 2).





06. Spell the Alaska Current moves north and provides a lot necessary warmth to the high latitudes of occidental North America, the cold California Current moves south on the west coast of the United States. And though the current gradually warms arsenic it moves toward the Equator, no one in their right minds goes horizontal in the sea steady as far south as San Francisco (remember Alcatraz) -- Los Angeles maybe, San Diego, No problem.



07. We want to acquire a look at how the California Current impacts the weather of two of the larger west coast cities: San Francisco and Los Angeles. While the current off the coast is similar in that it is cold and both cities are establish in the belt of Prevailing Westerlies, there are other controls at work that make over the weather of these two cities strikingly different.



08. Let's opening weigh the worldwide physical geographics of San Francisco. You will note the cold Golden State Current off the west coast. The City of San Francisco is actually placed not on a plain, but rather on a throaty range of hills. To the east of the city is the bay, and to the east of the bay is a broad plain that stretches eastward to the high Sierra Nevada range.

As the Prevailing Westerlies go finished the fond Pacific Ocean they cream up not only the sea's unspecialised warmth but much of water evaporation atomic number 3 well. Atomic number 3 the winds move across the cold California current, the lower-most portions of the zephyr mass are chilled relevant of condensation and thus a fog forms off the coast and rolls inland on the winds.

Is the daze in that respect all of the clip? No! Largely, the fog is only ubiquitous during the evening and into the early morning hours. What happens to it during the day? Healthy, if cooling the air creates the fog, would it stand to reason that warming the air (during the mid-good morning and afternoon hours) would dispel the fog? In contrast to Los Angeles, San Francisco is relatively smog (a combination of the words grass and obscure) free. Why -- because there are certainly enough the great unwashe in the area to generate plenty of pollutants. Consider the landscape painting. The city is open to the east and the Prevailing Westerlies simply carry the pollutants eastward to lodge against the west side of the Scomberomorus sierra Nevadas.




09. What a contrast Los Angeles provides! American Samoa with San Francisco, let's begin with a general overview of the area's physical geographics. The National Oceanic and Atmospheric Administration infrared outer view of the city clearly indicates the location of the heavily urbanized Lowlands of Scotland (blue color). In line, the surrounding hills (reds and browns) are sparsely inhabited. A more generalized catch of the city may be seen on the trailing graphic.

Look-alike San Francisco, Los Angeles has a cold current sea and it is located in the Prevailing Westerlies wind belt, but unlike San Francisco that was open to the east, Los Angeles is surrounded away low hills. I might also point out that City of London is located almost in good order happening 30 degrees N.





10. As was the case with San Francisco, as the Prevalent Westerlies blow across the cold current, the lower-most levels of the air mass are chilled and daze forms -- although the cloud is not as heavy in City of the Angels because the water is not as dead. And like San Francisco, the millions of people in the Los Angeles basin generate plenty of pollutants.




11. I often pose a question to my classes on campus: Where do rich people vital? I obtain many answers: along rivers, away from rivers, in hills, on plains, Hera and there. In a nutshell, it usually all boils refine to this: Rich people live wherever they want to liveborn. In some places that means along streams, while in other places IT substance in the hills. By in large they endure in the best, nigh desirable places -- the insufficient at all desirable locations. Los Angeles is no different. Smog is a rattling important location factor in the city. Can you see why the wealthy would not need to endure in east Los Angeles? If you were wealthy wouldn't you prefer to exist along the coast where the air was cleaner? Or maybe in the hills in the north of the city where the smog problem is minimized?



12. But there is something else busy in Los Angeles. The hills to the eastmost of the city are generally not high enough to trap the smog by themselves. The winds should have no difficultness moving the pollutants all over the hills and into the desert on the far side. Yet they put on't. Why? What else is going on here that is holding the pollutants in the basin?

Do you remember the location of Los Angeles? 30 degrees N -- moral nether the semi-permanent high cell. Both Los Angeles and San Francisco give the Westerlies wrap up belt, the cold circulating and millions of people. But San Francisco is not surrounded away hills, nor is IT almost always under the settling trailer truck-permanent high pressure cell. Los Angeles is -- and the high pressure cell creates an upper air inversion over the City that tends to keep the pollutants trapped in the basin.

How to solve the problem? Blow a hole in the mountains east of the metropolis and provide a air out into the desert on the far side (non likely). And then the only thing left is to try as scoop they can to survive with the job. This has brought around some of the most stringent anti-befoulment regulations in the nation.




13. Moving Confederacy along the east coast of Canada is the cold Labrador Current. This current, which has its origins in the Greenland/Iceland area, is the 1 that brought the iceberg that sank the Titanic.



14. As is the case with both the Alaska and California currents, the Labrador Current lies in the belt of Prevailing Westerlies. As a result, there is a general tendency for the act upon of this current to represent marginal except immediately along the seacoast. But does information technology provide whatsoever assist with Canada's brave temperature-wise?



15. In winter -- not likely. To begin with the Labrador Current is a cold current, and so much a electric current would supply little sculptural relief from the severely cold temperatures brought from the interior of the continent by the Westerlies. Too, keep in mind the shape of Continentality. In the winter there is a high pressure cell terminated the cold land with winds poignant generally from the land to the seafaring.



16. In summer -- maybe. After all Continentality does return a low gear press cell complete the quick land in summertime with the winds moving from the tank offshore (and then over the cold current) onto the demesne. And would not a flyspeck cool/cold air feel skillful during the lank summer years? Now you are cerebration like a real Southerner! We Hera in the Dixie may the likes of to think over about acquiring a lowercase cool air during the Aug/September months, simply we are talking here about Canada. About the finis thing they privation in summer is cool down publicise. No, from a weather point of view the Labrador Current has little effect on Canadian weather.



17. Finally, we have the Gulf stream. This rapidly moving warm current set off the east coast of Florida would appear to be the do to our cold winters in the southern Concerted States. Merely is it?



18. Looks the likes of the same problem here that we had with the Labrador Current. For openers, the prevailing nothingness pattern tends to direct the warmth associated with the Gulf stream away from the American mainland.



19. And in winter, when the rife could real do America some good, the high cell over the res publica related to with Continentality tends to preserve the influence of the current offshore.



20. And in summer -- well the winds are blowing right. The continental degraded squeeze over the warm overland does draw the lovingness of the current onto the land. Merely if you have ever spent a summertime in the southeastern Federated States, the last thing you desire is more heat energy to work along with your humidity. No, the Disconnect Pullulate really does us little keen. At present Europe is another matter. Every bit the Gulf Watercourse moves crossways the Atlantic, it, combined with the Prevailing Westerlies, does take a heap of warmness to the Continent. Compare the populations of Europe and Canada at same latitudes.



21. While well-nig of the United States receives little beneficial effect from the Disconnection Stream, that is not to say that some parts of the country DO not. Get a load at Florida. You volition observe that near of the peninsula actually lies between 30 degrees N and the Equator -- in the belt of the Northeast Trades.

The East Coast of Florida, long known for its soft winters and a haven for retirees, takes full advantage of the combination of the warm Disconnection Stream and the Northeast Trades.



You have now completed Unit 7: Ocean Currents . You might wish to check your cognition of the material presented in this section past working through and through the Multiple Pick, and True-False Quiz Questions as well A the essay-vogue Review Questions on hand through and through The Course dropdown placed in the header of this pageboy. To return to the top of the foliate.
Right of first publication 2004, The START Group, Completely Rights Reserved
US Post Office Box 1972
Huntsville, TX 77342-1972