Was That A Tsunami?

28 02 2010

T Street Gets Swamped

Nah.  It’s just Sunday morning at T Street (the day after the tsunami generated by the Chilean 8.8 earthquake).

There was a lot of water moving around this morning, as piles of water advanced toward the stairway, fire rings, bathrooms, and lifeguard headquarters.

The combination of an extreme high tide (6.2′) and a swell kicked up by the recent storm was just too much for San Clemente’s beaches.  As El Nino grinds away at the beaches, the City is trying to find a  way to help nature cope by bringing in more sand by truck or train or barge.  

It’s a tough call.   Once we’ve messed up the regional sand flow with various manmade devices, should we help nature out from time to time?  We hate to see our beaches disappear, even if they come back partially in the next season.  But, how much of the erosion is natural?

Perhaps that would be a good post in the future?  Maybe we could even get a guest expert.

In the meantime, stay on the bluff at high tide.  Just don’t get too close to the edge.





Tsunami Physics and Trestles

28 02 2010

Waves On The Way To Trestles

With the tragic 8.8 earthquake in Chile generating a tsunami that traveled across the Pacific, the question arises again — “Just what is a tsunami (Japanese for ‘harbor wave’)?”  We add “How will it affect Trestles?”

The news cams and looky-loo’s run down to the beach looking for a Mav size set to wash away all the local fish taco stands, but are sorely disappointed when they find out the tsunami passed by without even a splash.  That’s because while tsunamis are waves from a physics standpoint, they don’t behave like the waves most people are used to seeing in news photos and movies like Big Wednesday.

Ocean waves range in velocity, wavelength and frequency from wind chop to twice-a-day tides.  Tsunamis fit in the ocean wave spectrum somewhere between surf beat and tides.   So, they behave more like a big surge.

Ordinary wind-driven waves, like the ones breaking yesterday at Snapper Rocks, range from about 5 to 15 seconds in period between waves.  Surf beat varies greatly, but it is the more correct term for what surfers call “sets.”  When I was a kid, the old pro’s on the beach would say that every 9th wave was a big one.  That was a wild guess.  Surf beat frequency and period actually depend on a lot of variables, like wave height, velocity, and frequency, not to mention the shape of the ocean bottom (bathymetry) across which they travel.   With that said, surf beat is a multiple of wave periods.  For example, every ninth 10-second wave would mean the surf beat is 90 seconds.  Tides average about 12 hours between peaks.   Tsunamis are somewhere in between.

Tsunami Wave Geometry

This diagram, borrowed from EnchantedLearning.com, shows the difference in wavelength and velocity between deep water travel and shallow water travel for tsunamis.  It is obvious that tsunamis are greatly affected by bathymetry and ocean depth.

For more on tsunami physics, here is a great link.  I especially like the video on one of the pages on this site that shows how the 1960 Chile earthquake tsunami traveled across the Pacific.  It shows graphically why tsunami effects are so difficult to predict.  That’s why it is better to be safe than sorry when responding to tsunami alerts.

http://www.geophys.washington.edu/tsunami/general/physics/physics.html

In Southern California, nobody was really able to absolutely detect the tsunami as it passed, because it was mid-tide when it was predicted to occur.   But, if it had shown up a few hours earlier, at spring (seasonal high) tide, the story may have been a little more tragic for some low lying areas like Capistrano Beach or even Newport Beach.

As for Trestles, it was a Victory at Sea day, so a little more tsunami confusion would have just blended into the background.  The train tracks are still there.





San Mateo Creek Conservancy

23 02 2010
“Old Field” Cleanup Site is On South Side of the Trail

Tim Elsner figured it out — It’s the San Mateo Creek Conservancy!

They’re the ones doing all the habitat restoration along the trail between I5 and the beach.   The eucalyptus trees near the freeway were deemed to be non-native and were cut down.  The homeless camps at the bottom of the slope have been cleaned out.  All the old castor bean plants and wild anise have been replaced with new native shrubs.

The plan was laid out by the Conservancy.  I’m guessing they probably got some funding through the California Coastal Conservancy, though I don’t know that for a fact. The work is being contracted by the environmental arm of the California Park Service.   The replacement plants are being grown by Tree of Life nursery, one of the first native plant nurseries.  They’re just up the Ortega in San Juan Capistrano.

If you want a more detailed description of the work, check out the restoration plan at:

http://www.trestleswetlands.org/files/TrestlesWetlandsNaturalPreserveHabitatPreservation.pdf

or

www.trestleswetlands.org

Having been involved in wetlands restoration, I know how much these grass roots (excuse the pun) efforts are really labors of  love.  They depend on the personal dedication of those individuals who work many times quietly in the background saving our limited pristine areas and restoring them.   Well done San Mateo Creek Conservancy! 

Without getting political, whether you are a conservative Boy Scout or a “flaming environmentalist,” you can appreciate the natural outdoors and the value they bring to our lives.  As surfers, we depend on nature to bring us what we appreciate most — surf.   So, we can probably all embrace the current restoration efforts just up the trail from our favorite break.  Cheers to the natives (plants that is)!





Nike Making Trestles Safe

23 02 2010

Nike 6.0 is joining the Crowd. 

Evidently, in a gesture of good faith, Nike, partnering with the San Onofre Foundation and SurfriderFoundation, is sponsoring a design contest to create a safe, and  responsible way to move surfers from their cars to the beach, without destroying the natural environment.

This is a great opportunity for those professional and wannabe landscape architects out there to blend all those trails and railroad crossings into the background.  Please pass it on to any professionals, students and professors who are looking for some practical experience.  It would be even better if the contestants knew the space intimately so they can blend the surfing culture’s needs into the ecological needs of the site.

It’s great that our beloved Trestles is getting the attention it deserves.   Let’s see if Nike can live up to its desires to be green.  And, let’s give them all the support we can to get it done.

The contest, being organized by Architecture for Humanity, is called Safe Trestles.  Here is the link:

 http://openarchitecturenetwork.org/competitions/trestles





San Mateo Creek Keeps Flowing

22 02 2010

San Mateo keeps flowing after 4 weeks

In Southern California, we get so used to dry creeks, we are surprised when those creeks actually have water.

Not only did San Mateo Creek have water in it this year, it blew out the sand spit that forms the lagoon at Upper Trestles.  And, it has been flowing for about 4 weeks now.  With more storms lining up off the coast for the coming days, it is likely the creek will continue to flow for weeks more.

Surfers aren’t the only ones that like to see the creek flow, because it corrects the sand conditions in the lineup.  The beavers and steelhead have a chance to thrive.

The San Mateo Creek watershed is one of the last pristine areas left in Southern California.  It functions like a real watershed, filling with water when it rains.  Once the soil upstream gets filled like a wet sponge, it drains for weeks through the natural water course.  The result is  what we are seeing today.   Upstream, the plants and animals will thrive throughout the year.  Water is life!

Enjoy the water while it’s here.   The view from the lineup is refreshing.  You can even see the trestles again.

Veiw from the lineup at Uppers





Was That Tom Curren at Trestles Today?

22 02 2010

In that last few yards of the bike ride this morning, slowing down to go under the trestle, I looked over to see a guy walking and sipping his cup of jo.  We traded “good mornings.”  I thought “Man, that guy looks like Tom Curren.”  Looking down the beach, I saw the event tents and realized I probably wasn’t just seeing things.

WSA Event Tents -- February 21, 2010

The way I figure it, Tom had dropped off his youngest son Patrick, then went to park the car.  This was a WSA event.  I didn’t find Patrick on the ratings chart, but that’s my best guess.

Tom–welcome back to join the Crowd!  You’re always welcome to jump in with us.

As for you WSA chargers–sorry the waves were a little disappointing, but hopefully you snagged a couple of these rare waves.

Rare peak shows for the WSA event





California Surf Vacations

19 02 2010

Where did your travels take you on Valentine’s Weekend 2010?

“Sorry hun, we’re doing a staycation this weekend.”  That was heard  in most surf households in California last weekend.   With almost every surf spot on the coast lighting up and epic weather, the freeways were packed with surfers trying out spots other than their own.

And, Mav’s put on an unbelievable paddle-in show.  Have you seen this video on Surfline?  You can smell the testosterone.

http://www.surfline.com/video/contests/mavericks-surf-contest-highlights_41179

Me, I hung out at my old home:  54th Street.  Not huge, but a ton of fun?  I had to put my new board on ice after a couple speed runs.

Where did you surf last weekend?  If it’s not a secret, let us know with a comment.