Why is the water so cold? (Los Angeles, San Diego: beaches, swimming, lifeguard)

[Gentoo]

Originally Posted by KC6ZLV

The climate is why we have the cold water off the coast. The wind causes the ocean currents.

Not really. The earths rotation is the main driving force. This is the reason why the currents generally go clockwise in the northern hemisphere and counter clockwise in the southern. The earths rotation causes a general east to west movement near the equator. The positioning of colder water next to a warm body of land creates a pressure gradient. As warm air from the interior rises due to it being less dense, heavier cool air rushes in which is what gives the Ca. coast it's sea breezes.

[Fontucky]

Another benefit of our cold water: it won't support hurricanes/typhoons.

[Hawk J]

When we were younguns we swam in the water at Monterey,Carmel, Seaside, & Marina beach. The COld doesn't bother the Young...

http://bestsmileys.com/sports3/10.gif (broken link)

[KC6ZLV]

It is amazing that whatever you post on here someone will come along and tell you otherwise.

Originally Posted by Gentoo

Not really. The earths rotation is the main driving force. This is the reason why the currents generally go clockwise in the northern hemisphere and counter clockwise in the southern. The earths rotation causes a general east to west movement near the equator. The positioning of colder water next to a warm body of land creates a pressure gradient. As warm air from the interior rises due to it being less dense, heavier cool air rushes in which is what gives the Ca. coast it's sea breezes.

The Earth's rotation by itself doesn't cause water, or air to move. The differences in temperature and density are what cause both air and water to move. The Coriolis effect is what causes a deflection of movement of air or water.

Now, if you take the time to look at the dominant global high and low pressure systems you will see the direction of ocean currents follow these high and low pressure systems, as well as the direction of trade winds in the tropics. The exceptions being landmasses that are in the way and deep sea currents, which generally flow in the same direction as air , but not as in the same pattern as the sea surface currents.

[Gentoo]

Originally Posted by KC6ZLV

It is amazing that whatever you post on here someone will come along and tell you otherwise.



The Earth's rotation by itself doesn't cause water, or air to move. The differences in temperature and density are what cause both air and water to move. The Coriolis effect is what causes a deflection of movement of air or water.

Now, if you take the time to look at the dominant global high and low pressure systems you will see the direction of ocean currents follow these high and low pressure systems, as well as the direction of trade winds in the tropics. The exceptions being landmasses that are in the way and deep sea currents, which generally flow in the same direction as air , but not as in the same pattern as the sea surface currents.

Sorry for not being clear.

I didn't mean to imply that the rotation caused the water and air to move. What I meant to get across is that the rotation influences the direction which it moves. Both the water as well as the air tends to turn toward the west near the equator. With the winds, these are the trade winds and like the ocean currents in that area, the tend to bend westward. The earths rotation does effect wind direction; even the rotation of storms, both temperate and tropical hurricanes are influenced by the earths rotation. Yes wind does move due to differences in pressure however the winds tend to move in specific directions as well; polar winds and predominantly easterly (blowing from eat to west), mid latitude winds are predominantly westerly and tropical trade winds again are mostly easterly. As the earth rotates the wind direction tends to bend in response.
http://en.wikipedia.org/wiki/Coriolis_effect

[sdurbanite]

Originally Posted by gone down south

You think the water in San Diego is cold? Never visit San Francisco then!

So true. By Florida standards, the water temps in SD are considered cold, but compared to the waters off Northern California, our waters are downright warm!

[evergraystate]

Look at all that 80f+ water just south of the border. If only northern Mexico wasn't such a complete mess.

[tstieber]

Originally Posted by .highnlite

The ocean of CA is not cold, drive up to Tahoe, take a long swim, drive back to the beach and dive in, it will feel rather balmy.

Depends on the time of year. Last year, we were in Tahoe in early August, it was close to 90 degrees outside, humid, with thunderstorms building up, and the surface of the lake at least was like bathwater. I realize the deeper you go, the colder it gets, but for plain old beach swimming, Tahoe is way warmer. You can also go to some of the reservoirs around the state for warmer inland water.

I put my feet in the water in San Diego a week ago, and it was pretty chilly. Not the bone chilling cold of San Francisco water, but not inviting.

[tstieber]

Originally Posted by evergraystate

Look at all that 80f+ water just south of the border. If only northern Mexico wasn't such a complete mess.

The Gulf of California is only about a 2-3 hour drive from the California border, and it's totally not influenced by the California Current at all. But I worry about heading that way too, and I don't think there are very big towns there. I wonder if the climate would support coconut palms along the gulf, if they were watered. I assume winters wouldn't be warm enough until you got farther south though.

Where is SD's water temp measured? I was just on Wunderground, and they have La Jolla at 68 and "San Diego" at 71+, but I thought that higher temp might be inside the bay? Heck, even Alameda bay beaches near SF are at 68. I don't like bay swimming, but I would imagine SD's Mission Bay must get REALLY warm being all shallow, especially on days when there's no marine layer like today. Anyone know if there's a water temp for Mission Bay?

SD water definitely gets much warmer than LA water though -- I don't think I've ever seen LA water temps out of the 60s. SD always nudges above 70 by late summer.

[.highnlite]

Originally Posted by tstieber

Depends on the time of year. Last year, we were in Tahoe in early August, it was close to 90 degrees outside, humid, with thunderstorms building up, and the surface of the lake at least was like bathwater. I realize the deeper you go, the colder it gets, but for plain old beach swimming, Tahoe is way warmer. You can also go to some of the reservoirs around the state for warmer inland water.

I put my feet in the water in San Diego a week ago, and it was pretty chilly. Not the bone chilling cold of San Francisco water, but not inviting.

In shallow water close to shore Tahoe can be warm, but for actual swimming tis a bit chilly.

I used to water ski each evening one summer, nice boat, it had a towel warmer, we needed it.

I grew up recreating at the ocean, Pismo Beach, I never found the water too cold.

A story, at one point in my life I lived in Naples Italy. A few friends and I went over to the nearby island of Ischia, drank red wine and slept on the beach. Early in the morning I got up to take a dive into the ocean, to clear my head and warm up. I ran out, dove in, it was like diving into warm spit. A shock to anyone accustomed to the refreshing waters of the California Pacific.