The Earth is a Fascinating Globe – The Seas
The earth teems with diverse ecosystems and landscapes. Our oceans are no exception and are the cradle of life on the planet.
Water covers approximately 71% of the surface of the Earth, with continents and islands accounting for the remaining 29%. The seas also hold 96.5% of all the water on Earth, whereas the rest of the 3.5% are lakes and rivers of freshwater and frozen water trapped in glaciers and polar ice caps. Almost all of that fresh water is in the form of ice: 69%, to be exact.
The oceans have always provided a particular fascination for me, and I thought sharing some of the phenomena of its ‘mysteries’ might be interesting for you also – even if just revisited.
So, here goes. Consider it a welcome change to my usual Sunday blog and visit about some aspects of our amazing planet.
The sea level is different on each side of the Panama Canal. The Pacific Ocean is about 16 inches higher than the Atlantic at that point and stays that way up the US west coast. The twelve locks that ships making the 40-mile trip require them to elevate and lower 28 yards to get over the terrain of the canal – as well as raise or lower to the sea level at each end.
We tend to think that water is always level, that it’s only natural that water seeks the same level. What we sometimes forget is that the earth is round, not flat. Remember Columbus? The Pacific Ocean experiences higher tides, stronger currents, higher salinity, and higher temperatures compared to the Atlantic Ocean. The level of oceans and seas vary around the globe dependent on those and other factors.
The surfer waves are higher on the west coast and Hawaii because the continental shelf is shorter there. One can walk out a much longer distance on the east coast before one reaches a deep drop-off. Also the prevailing winds are generally behind the waves on the west as opposed to generally into the waves on the east coast.
When we think of waves, we think the water is moving. It’s not. Wind is what makes waves and what we see is the energy of the wind passing through the water.
You might ask what sea level is and how it is measured. The book says a common and relatively straightforward mean sea-level standard (MSL) is a long-term average of tide gauge readings at a particular reference location. So, it’s not so simple. Precise determination of MSL is difficult because of the many factors that affect sea level. The MSL at a particular location may be calculated over an extended time period and then used as datum. For example, hourly measurements may be averaged over a full Metonic 19-year lunar cycle to determine the mean sea level at an official tide gauge. Sound complicated? It is – and affected by a plethora of variables. (Think of that the next time a climate change convert tells you s/he knows that Miami will soon be underwater.)
Speaking of the lunar cycle, the oceans are affected by our orbiting moon’s gravity resulting in high and low tides, with water moving up and down our shorelines. So, sea level changes daily at any shore’s location.
As one looks out over the ocean, how far is the horizon? As it turns out, pretty far. From the shore the average human eye with 20/20 vision, can see about 3 miles out – which is where the curvature of the earth bends away from the surface and is no longer in view.
We’ve all heard of tsunamis. They are created by below the sea earthquakes and/or volcanic eruptions. As the water is forced upward, gravity acts down on it, forcing the energy out horizontally. That energy travels through the depths and away from the initial disturbance. The force of the seismic disturbance can travel at incredible speed. And that speed is influenced by the depth of the water – faster in deep water and slower in shallow water. A tsunami can travel at hundreds of mph under the surface while being barely noticeable on the surface. Once a tsunami gets close to shore, it takes its more recognizable and deadly form.
Finally in today’s ocean exploration, we look at hurricanes (cyclones or typhoons on the other side of the world).
Hurricanes are low atmospheric pressure cells that spiral out of tropical regions and over the ocean near the equator. Such a cell could already be a thunderstorm, but in any case, once over the ocean it sucks up warm tropical air from the water surface and dispenses cooler air aloft. Heat rises. When such a system grows to support winds of 74mph, we call it a hurricane. And it will continue to grow until it hits something – like land – or a high-pressure system. Hurricane winds, reaching up to a record 185 mph, can generate ocean waves over 50 feet high.
The ocean’s deepest point is the Mariana Trench at 36,201 feet, which is deeper than the tallest mountain on land. It’s estimated only about 5% of the ocean’s floors have been explored.
So. Atlantis could still be down there.
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Have a great and prosperous week.
Hug somebody.
References:
https://www.studycountry.com/wiki/is-sea-level-the-same-at-both-ends-of-the-panama-canal
https://science.howstuffworks.com/environmental/earth/question623.htm
https://sigmaearth.com/how-much-earth-is-covered-with-water/#google_vignette
https://www.worldatlas.com/articles/10-ocean-mysteries-that-still-boggle-the-mind.html
SPIDER Byres
This week’s trivia question is: What is the only planet in our solar system to rotate clockwise on its axis? The answer to last week’s question re the company that owns the Bugatti, Lamborghini. Audi, Porsche, and Ducati: Volkswagen. Volkswagen Group currently owns 12 car companies or brands, including Volkswagen, Seat, Audi, Skoda, Bugatti, Bentley, Lamborghini, Ducati, Porsche, Scania, MAN, and Volkswagen commercial vehicles. It has 6% of the world’s car market, second only to Japan-based Toyota.
We had what’s called a Blood Moon in the early hours of Friday morning. The total lunar eclipse of the Full Moon turned the sphere into a rusty reddish color. Did you see it? BTW, no Blue Moon this year.
Dah. High demand for any product raises the price when supply can’t meet it. Egg prices are coming down because the price thereof has decreased demand as consumers won’t/can’t pay the higher price. So, as egg sales decrease the price goes down as well.
Inflation in February rose 2.8% over a year ago, and .2% over January. Still off the year-to-year target of 2% although gas prices are now falling.
An election in Greenland last week showed the electorate wanted independence from Denmark. The US does have a Space Force Base in the NW section of the island. (formerly Thule Aie Base)
Last week the federal government paused funding to the entire public education program in Maine due to the state’s refusal to comply with President Trump’s order banning men from competing in women’s sports. Funding of Columbia U. was previously halted for refusing to protect Jewish students from violent anti-Semitic protests and encampments on campus.
Michelle Obama joined the club by launching her own podcast last week. She joins CA Gov. Newsom trying to use the forum for their own purposes.
A DOGE audit resulted in deactivating 200,000 government credit cards spread among 16 agencies. There are still 4.4 million cards active in the government. Some of the numbers coming out about this bloated government are mind-blowing. Meanwhile the President and Linda McMahon, Secretary of Education, is cutting the number of its employees in half on a track to eliminate the Dept altogether.
The FBI issued a nationwide ‘smishing’ warning to iPhone and Android users as some 10,000 domains have been registered by cybercriminals. The fraudulent aim is to send text messages designed to steal personal and financial information. Toll road scams are prevalent. ‘Phishing’ remains a similar threat using emails.
Several Departments and the EPA froze funds in February and then last week filed additional documents requesting Citibank freeze some $27B appropriated by the Inflation Reduction Act to fund non-profits for green technology projects. Citibank had been selected to hold and administer the money.
Remember when a national weather forecast predicted how a major storm front moving across the country would affect specific regions, states and cities? Now, it refers to the millions of people impacted. It’s much more sensational, don’t you think?
The 2035 ban on the sale of all gas-powered vehicles will begin the process in 2026 when 35% of sales in these states must be electric: New York, California, Oregon, Washington State, Massachusetts and Vermont. Politicians in those states were so caring and smart in 2022 when the bans were enacted. I presume residents could buy a combustion engine vehicle in another state, so border dealers must be licking their chops.
SpaceX launched its capsule to ISS Friday evening to take up four astronauts and pick up the two stranded there. It docked last night.
